ARTICLE | doi:10.20944/preprints202205.0069.v1
Subject: Medicine & Pharmacology, General Medical Research Keywords: Volatile organic compound; VOC; headspace; breath; breath biomarker; volatile metabolite; breath diagnosis
Online: 6 May 2022 (09:27:04 CEST)
Volatile compounds, abundant in breath, can be used to accurately diagnose and monitor a range of medical conditions. This offers a non-invasive, low-cost approach with screening applications; however, uptake of this diagnostic approach has been limited by conflicting published outcomes. Most published reports rely on large scale screening of the public, at single time points and without reference to ambient air. Here, we present a novel approach to volatile sampling from cellular headspace and mouse breath that incorporates multi-time point analysis and ambient air subtraction revealing compound flux as an effective proxy of active metabolism. This approach to investigating breath volatiles offers a new avenue for disease biomarker discovery and diagnosis. Using gas chromatography mass spectrometry (GC/MS), we focus on low molecular weight, metabolic substrate/by-product compounds and demonstrate that this non-invasive technique is sensitive (reproducible at ~1 µg cellular protein, or ~500,000 cells) and capable of precisely determining cell type, status and treatment. Isolated cellular models represent components of larger mammalian systems and we show that stress- and pathology-indicative compounds are detectable in mice, supporting further investigation using this methodology as a tool to identify volatile targets in human patients.
ARTICLE | doi:10.20944/preprints201807.0562.v1
Subject: Chemistry, Analytical Chemistry Keywords: GC-MS; SPME; Tom Yum soup; volatile compounds; extra volatile compounds; aroma compounds; sniffing analysis
Online: 30 July 2018 (06:25:04 CEST)
Gas chromatography-olfactometry/mass spectrometry coupled with headspace-solid phase microextraction (HS-SPME/GC-O/MS) was applied for the characterization of volatile compounds in Tom Yum soup and its individual ingredients. Using HS-SPME with a 50/30 µm DVB/CAR/PDMS fiber and an extraction temperature of 40 °C for 50 min along with an HP-5MS capillary column, 101 peaks in the HS-SPME/GC-MS chromatogram of Tom Yum soup were detected, and 96 compounds were identified including alcohols, aldehydes, esters, ethers, and terpenes. These findings are based on the comparison of MS spectra with the NIST library as well as experimental and literature retention index data. In comparison with the compound profiles of each individual ingredient of Tom Yum soup (both before and after cooking), five extra volatile compounds in Tom Yum soup were found after the cooking process. Furthermore, odor descriptions of the eighteen aroma compounds in Tom Yum soup, along with the odor ingredient sources, were also obtained.
ARTICLE | doi:10.20944/preprints202203.0120.v1
Subject: Biology, Animal Sciences & Zoology Keywords: magnesium; absorption; rumen; butyrate; volatile fatty acids
Online: 8 March 2022 (08:59:14 CET)
The aim of the present study was to measure the apparent absorption of magnesium (Mg) originating from Mg-butyrate. Six mid-lactation Holstein Friesian dairy cows were used with dietary treatments arranged in a cross-over design. Two different diets were fed during the experiment, consisting of a low Mg diet without Mg-butyrate (L-Mg, 3.1g Mg/kg dry matter) or a high Mg diet with Mg-butyrate (H-Mg, 3.9 g Mg/kg dry matter). Cows offered the L-Mg diet ingested 54.7 g Mg/day while the cows fed the H-Mg diets ingested 66.3 g Mg/day (P < 0.001). The fecal excretion of Mg, however, was similar between the two experimental diets (P = 0.174). Consequently, apparent Mg absorption was found to be 7.9 percentage units greater (P = 0.038) when the cows were fed the diet supplemented with Mg-butyrate. The greater Mg absorption after feeding the H-Mg diet was, however, not reflected by a greater urinary Mg concentration (P = 0.228). These results indicate that the availability of Mg from the Mg-butyrate supplemented diet is high (34.1% of intake). The fractional Mg absorption from Mg-butyrate was calculated to be 71.6%. In conclusion, Mg-butyrate is an attractive alternative to supplement dairy rations with Mg.
ARTICLE | doi:10.20944/preprints202101.0170.v1
Subject: Earth Sciences, Atmospheric Science Keywords: Air pollution; environmental hazards; Volatile Organic Compounds
Online: 8 January 2021 (16:59:01 CET)
Air pollution is a serious global issue, responsible for approximately one in every nine deaths each year, ranking it among the greatest environmental hazards to human health. It is of particular concern in urban areas, where elevated pollutant concentrations and potential sufferers converge. Over one half of the world’s population presently lives in urban areas, and the urban population ratio is expected to reach 68% by 2050. Common air pollutants include particulate matter (PM), sulphur dioxide (SO2), ground-level ozone (O3), nitrogen oxide (NOx) and carbon monoxide (CO). While elevated rates of air pollution pose serious health risks for humans, outdoor plants can help reduce the harmful effects of air pollution by filtering and purifying the air around us.In this project Common Ivy, Aster and Miniature Andromeda plants were evaluated for air pollutant mitigation. In this study we developed a vegetation barrier model with the plant located in the middle of the greenhouse box, and air pollutant was sprayed on one side of the plant. Dispersion patterns of sprayed pollutants were tested with and without vegetation barrier. Measurements of carbon dioxide (CO2), Formaldehyde (HCHO), Total Volatile Organic Compounds (TVOC), and Particulate Matter (PM2.5/PM10) were taken before spraying, then at 0 and 30 minutes after spraying, using both monitors.The results show mitigation rates (in 177 ft3 of air after 30 min): for TVOC the minimum reduction is 5 mg/m3; for HCHO, 1 mg/m3; for CO2, 2000 ppm; for PM2.5, 2000 ug/m3; and for PM10 it was 1000 ug/m3.
ARTICLE | doi:10.20944/preprints202007.0687.v1
Subject: Chemistry, Applied Chemistry Keywords: Gamma-ray, Mutant, Rose, Volatile compounds, GC-MS
Online: 29 July 2020 (09:46:55 CEST)
Roses are one of the most important floricultural crops, and their essential oils have long been used for cosmetics and aromatherapy. We investigated the volatile compound compositions of 12 flower-color mutant variants and their original cultivars. Twelve rose mutant genotypes were developed by treatment with 70 Gy of 60Co gamma irradiation of six commercial rose cultivars. Essential oils from the flowers of the 18 genotypes were analyzed by gas chromatography–mass spectrometry. Seventy-seven volatile compounds were detected, which were categorized into five classes: hydrocarbons, terpenoids, alcohols, esters, and others. Hydrocarbons, alcohols, and esters were major components in all rose flowers. The mutant genotypes CR-S8 and CR-S9 showed higher contents of hydrocarbons than the original cultivar. In addition, CR-S1, CR-S3, and CR-S4 mutant genotypes showed higher ester contents than their original cultivar. Nonacosane, 2-methylhexacosane, and 2-methyltricosane were major volatile compounds among all genotypes. Hierarchical cluster analysis of the rose genotypes gave four groups according to grouping among the 77 volatile compounds. These findings will be useful for the selection of rose genotypes with improved volatile compounds.
ARTICLE | doi:10.20944/preprints202002.0274.v1
Subject: Chemistry, Food Chemistry Keywords: Chemical profiles; taxonomical description; volatile compositions; Zanthoxylum spp.
Online: 19 February 2020 (10:54:48 CET)
In order to obtain makhwean (MK) fruit essential oil of constant aromatic profile during raw material sourcing, evaluation of relationship between genotype, phenotype and chemical profiles are necessary. Three specimens of the MK (MK1-3) distributed in Northern Thailand were genetically and morphologically compared with other Zanthoxylum spices known locally as mamaad (MM) and makwoung (MKO), respectively. MM was taxonomical confirmed as Z. armatum based on plant structure and leaf characteristic (Odd-pinnately compound leaf). MKO and MK were identified as Z. rhetsa and Z. myriacanthum using number of petals and anthers. Genetic sequencing by Internal Transcribed Spacer (ITS) sequence and Random Amplified Polymorphic DNA moreover, divided these Zanthoxylum spps. into three groups accordingly to their species viz., MM, MKO and MK. Essential oil of the dried fruits from these samples was extracted and analysed for physical and chemical profiles. Cluster analysis (PCA-biplot) of volatile compositions was able to separate 1) MK1 and MK3 with limonene as leading component, 2) MK2 and MKO related with sabinene and β-philandrene, 3) MM with linalool. By using odour attribute representatives, the essential oil of MKO and MK1-3 were closely related possessing fruity, woody and citrus aromas, while the MM was sweet/ floral. In summary for MK raw material sourcing, plant genotyping played the most important role to odour characteristics than growing locations, thus plant species confirmation should be first considered.
REVIEW | doi:10.20944/preprints201904.0140.v1
Subject: Chemistry, General & Theoretical Chemistry Keywords: waste cooking oils; plasticizers; syngas; volatile organic compounds
Online: 11 April 2019 (10:32:33 CEST)
The consideration toward Waste Cooking Oils (WCOs) is changing from hazardous waste to valuable raw material for industrial application. During the last five years some innovative processes based on the employment of recycled WCO have appeared in the literature. In the present review article, the most recent applications of recycled Waste Cooking Oil are reported and discussed. These include the production of bio-plasticizers, the application of chemicals derived from WCOs as energy vectors, and the use of WCOs as solvent for pollutant agents.
BRIEF REPORT | doi:10.20944/preprints201801.0286.v1
Subject: Biology, Entomology Keywords: volatile fatty acids; Alphitobius diaperinus; locomotor activity; repellency
Online: 30 January 2018 (14:46:51 CET)
Volatile fatty acids (VFAs) are a group of common metabolites with a potential of universal infochemicals dedicated to transferring of information between higher organisms and bacteria either from microbiome or external environment. VFAs are common substances among various insect orders, there are numerous studies exploring their influence on the behavior of different insect species. In relation to papers published by J. E. McFarlane, we assess the effects of formic, acetic, propionic, butyric, valeric acids on spatial preference of common stored food grain products, and poultry industry pest – lesser mealworm (Alphitobius diaperinus). We present novel method of continuous, simultaneous assessment of site preference as well as travelled distance in constant-flow olfactometer. All tested VFAs except valeric had a significant repellent effect with formic acid being effective in the lowest concentration. Additionally, VFAs significantly altered distance travelled by insects. Obtained results indicate a potential role of VFAs in the olfactory guided behavior of A. diaperinus, we speculate that reaction to the presence if VFAs may deviate form specificity of species’ original habitat.
ARTICLE | doi:10.20944/preprints201607.0093.v1
Subject: Mathematics & Computer Science, Information Technology & Data Management Keywords: Non-volatile Memories; NAND Flash Memories; Storage Memories
Online: 29 July 2016 (13:40:38 CEST)
This paper presents an upcoming nonvolatile memories (NVM) overview. Non-volatile memory devices are electrically programmable and erasable to store charge in a location within the device and to retain that charge when voltage supply from the device is disconnected. The non-volatile memory is typically a semiconductor memory comprising thousands of individual transistors configured on a substrate to form a matrix of rows and columns of memory cells. Non-volatile memories are used in digital computing devices for the storage of data. In this paper we have given introduction including a brief survey on upcoming NVM's such as FeRAM, MRAM, CBRAM, PRAM, SONOS, RRAM, Racetrack memory and NRAM. In future Non-volatile memory may eliminate the need for comparatively slow forms of secondary storage systems, which include hard disks.
ARTICLE | doi:10.20944/preprints202111.0238.v1
Subject: Chemistry, Chemical Engineering Keywords: volatile suspended solids; anaerobic digestion; hydrogen; sour cabbage; microaeration
Online: 12 November 2021 (17:04:00 CET)
In the article, were checked influences of microaeration, pH, and VSS (Volatile Suspended Solid) for sour cab-bage anaerobic digestion. Results fermentation of sour cabbage under the condition of small oxygen addition are presented in this research can be classified as dark fermentation or hydrogenotrophic anaerobic digestion. The investigations were carried out for two concentrations 5 g VSS /L and 10 g VSS /L of sour cabbage at pH 6.0. The oxygen flow rates (OFR) for 5 g VSS /L were in the range of 0.53 to 3.3 mL/h for obtaining 2% to 8% of oxygen. In cases of low pH and microaeration, ethylene production was observed at a level below 0.05% in biogas. The highest volume of hydrogen for 5 g VSS/L was obtained for flow rate 0.58 O2 mL/h, giving hydrogen concentration in biogas in the range of 0 to 20%. For VSS 5 g/L and oxygen flow rate 0.58 mL/h; 0.021 L of hydrogen is produced per gram of VSS. In this case, VSS 10 g/L and oxygen flow rate 1.4 mL/h at pH 6.0, 0.03 L of hydrogen is generated per gram. Microaeration from 0.58 mL/h to 0.87 mL/h was propitious for hydrogen production at 5 g VSS/L of sour cabbage and 1.4 mL/h for 10 g/L. Another relevant factor is the volatile suspended solid factor of sour cabbage that caused optimal hydrogen production at VSS 89.32%.
ARTICLE | doi:10.20944/preprints202109.0081.v1
Subject: Chemistry, Food Chemistry Keywords: rootstocks; untargeted metabolomics; features; grafted; multivariate analysis; volatile compounds
Online: 6 September 2021 (09:52:40 CEST)
To allow for a broad survey of subtle metabolic shifts in wine caused by rootstock and irrigation, an integrated metabolomics-based workflow followed by quantitation was developed. This workflow was particularly useful when applied to a poorly studied variety cv. Chambourcin. Allowing volatile metabolites that otherwise may have been missed with a targeted analysis to be included, this approach allowed deeper modeling of treatment differences which then could be used to identify important compounds. Wines produced on a per vine basis, over two years, were analyzed using SPME-GC-MS/MS. From the 382 and 221 features that differed significantly among rootstocks in 2017 and 2018 respectively, we tentatively identified 94 compounds by library search and retention index, with 22 confirmed and quantified using authentic standards. Own-rooted Chambourcin differed from other root-systems for multiple volatile compounds with fewer dif-ferences among grafted vines. For example, the average concentration of β-Damascenone present in own-rooted vines (9.49 µg/L) was significantly lower in other rootstocks (8.59 µg/L), whereas mean Linalool was significantly higher in 1103P rootstock compared to own-rooted. β-Damascenone was higher in regulated deficit irrigation (RDI) than other treatments. The workflow outlined not only was shown to be useful for scientific investigation, but also in creating a protocol for analysis that would ensure differences of interest to industry are not missed.
ARTICLE | doi:10.20944/preprints202208.0395.v1
Subject: Engineering, Control & Systems Engineering Keywords: asymptotically observer; homogeneous reaction systems; anaerobic digestion; volatile fatty acids
Online: 23 August 2022 (05:18:34 CEST)
This work presents a methodology that seeks to be a new standard in modeling identification in anaerobic digestion reactors. Because it is not possible to measure all variables with reliable and cost-efficient real-time methods, a specific structure composed of an asymptotic observer for the concentration of state variables; acidogenic and methanogenic bacterias, unlock the use of new types of raw sludges for industrial control and monitoring purposes. New yield parameters were included in the reduced anaerobic digestion model (ADM2) used as the core, precisely two terms in total alkalinity, to bring about the modeling of additional organic materials at inlet containing proteins or amino acids. The fermentation of these substances introduces ammonium, providing variations in the amount of alkalinity available inside the reaction. The new model is used to solve an optimization problem that calculates the parameters that best fit the dynamics of state variables with the same information taken on the experimental data. The adjustment process started with the genetic algorithm; however, to improve the performance, a novel method is proposed called step-ahead. Together, including the design of an asymptotic observer, numerical simulations demonstrate the strengths of the structure, which constitutes a significant step in paving the way further to implement feasible, cost-effective control and monitoring systems in the industry.
ARTICLE | doi:10.20944/preprints202201.0125.v1
Subject: Earth Sciences, Geochemistry & Petrology Keywords: benchtop fumarole; flow-through reactor; sublimates; volatile metal species; simulation
Online: 10 January 2022 (15:19:35 CET)
Volcanic fumaroles are openings in the earth's surface, where volcanic gases discharge to the atmosphere. Metallic and non-metallic elements contained in gases form specific mineral precipitates upon cooling. Although the presence of metals in fumarolic gases has long been known, their concentrations are generally low and difficult to measure directly. A laboratory model of a fumarole may resolve the situation if the complex gas composition could be accurately reproduced. Here we describe a new experimental approach that allows accurately simulating fumarolic gases in terms of their main components (H2O, CO2, S, HCl), as well as adding volatile metal compounds. Gas is generated inside a special flow-through reactor, at the outlet of which the elements contained in the gas form temperature-dependent mineral sequence inside the attached silica-glass tube. Using this installation, we obtained laboratory sublimates from reducing (H2S-rich) gases similar to natural ones in terms of mineral composition and mineral habits. Twenty-one phases have been identified in sublimates, among which are simple and complex chlorides, simple sulfides and six sulfosalts. Comparison of the sublimate deposition from H2O-rich gas at 1 bar with similar works performed in evacuated ampoules at low pressure showed that fumarolic gases behave like an ideal gas, in which molecules do not interact with each other, and reactive compounds in the gas serve in fact as an inert carrier of volatile metals species. Changing the composition of the gas at the outlet of the installation, its flow rate and temperature, we can observe the corresponding changes in mineral precipitates and in such a way study the factors affecting mineral formation on natural fumarolic fields.
ARTICLE | doi:10.20944/preprints202011.0674.v1
Subject: Life Sciences, Biochemistry Keywords: chitosan; microbial synthesis; milk composition; volatile fatty acids; purine derivatives
Online: 26 November 2020 (14:15:52 CET)
The study compared the influence of chitosan sources on rumen fermentation, methane emission and milk production in lactating dairy cows fed a glycerin-based diet. Six, lactating Holstein-Frisian crossbreeds (410 ± 5.0 kg BW, 120 ± 21 day-in-milk), were arranged in a 3 x 3 replicated Latin square design. In addition to control, a 2% chitosan extract supplement and a 2% commercial chitosan supplement of dry matter intake were the treatments. The results denoted that no significant differences on daily dry matter, nutrients or estimated energy intake were noted when cows received different sources of chitosan. Nutrient digestibility was not influenced differently by extraction based or commercial chitosan supplements. The pH, temperature, ammonia nitrogen, blood urea and microbial count were similar among treatments. The different sources of chitosan supplements did not change the totals of volatile fatty acids, acetate and butyrate; in contrast, different chitosan sources influenced (P<0.05) propionate content. The ruminal acetate to propionate ratio was markedly (P<0.05) reduced with chitosan supplement, but no change appeared between sources of chitosan. At 4 hours after feeding, the methane estimation signiﬁcantly decreased with the addition of chitosan supplementation (P<0.05) compared to the control group. The purine derivatives and microbial protein synthesis were not altered by the treatments. No significant differences existed on milk yield, milk composition or milk urea nitrogen when cows received different sources of chitosan (P>0.05). In sum, supplementing extracted chitosan showed more potential than did commercial chitosan for enhancing economic efficiency and recycling shrimp residues, therefore, reducing environmental waste.
ARTICLE | doi:10.20944/preprints202008.0631.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Acidity attributes; fruit minerals; grapevine physiology; phenolic compounds; volatile compounds
Online: 28 August 2020 (10:20:31 CEST)
Kaolin protective effect was assessed in a white grapevine cultivar ‘Cerceal’ in ‘Alentejo’ Region (southeast Portugal) where plants face extreme conditions during summer season. We addressed the hypothesis that kaolin effects lead to several changes in leaves, fruits and wine characteristics on the primary and secondary metabolism. Results showed that kaolin reduces leaf temperature which provoke an improvement in physiological parameters such as net photosynthesis and water use efficiency. This protection interferes with berries colour, leaving them more yellowish, and an increase in phenolic compounds were observed in all fruit tissues (skin, seed and pulp). Also, both berry and wine characteristics were strongly affected, with an increase of tartaric and malic acid and consequently high total acidity, while the sugar concentration decreased 8.9% in berries provoking a low wine alcohol level. Results also showed that kaolin induces high potassium, magnesium and iron, and low copper and aluminum concentrations. Moreover, the control wine showed higher content of esters related with hostile notes whereas wine from kaolin treated vines presented higher content of esters associated with fruity notes. Overall, the results strengthen the promising nature of kaolin application as summer stress mitigation strategy protecting grapevine plants and improving fruits quality and more balanced wines.
REVIEW | doi:10.20944/preprints201804.0215.v1
Subject: Materials Science, General Materials Science Keywords: fly ash; nanocomposite; environmental pollution; volatile organic compounds; heavy metal
Online: 16 April 2018 (16:15:22 CEST)
Air pollutants such as volatile organic compounds (VOCs), nitrogen oxides (NOx), sulfur dioxide (SO2), as well as water pollutants including heavy metal, are harmful to human and environment. Effective control and reduction of their pollution is therefore an important topic for today’s scientists. Fly ash (FA) is a type of industrial waste that can cause multiple environmental problems if discharged into the air. On the other hand, because of its high porosity, large specific surface area, and other unique characteristics, the FA can also be used as a low-cost and high efficient adsorbent with some simple modifications. This paper reviews the effects of FA on treatment of the above air and water pollution based on our research experience over many years, including to the current status of global FA utilization, physicochemical properties, principle of adsorption, and the application direction of FA in the future. It focuses on the use of nanocomposite technology to fabricate functional FA fibrous membranes to adsorb VOCs from air, and treat heavy metal wastewater. This present review first describes the fabrication technology of FA nanocomposites and their mechanism of adsorption VOCs from air. Utilization of nanofiber technology to fabricate multi-functional FA emerging composite materials to mitigate air and water pollution has great potential in the future, especially use of pollutant material to control other pollutants.
ARTICLE | doi:10.20944/preprints201612.0007.v1
Subject: Chemistry, Food Chemistry Keywords: acetic fermentation; alcoholic fermentation; submerged process; volatile compounds; acetic bacteria
Online: 1 December 2016 (10:47:37 CET)
The alcoholic fermentation process with agitation/static, followed by the acetic fermentation submerged in banana was evaluated. Kinetics parameters of alcoholic fermentation for the maximum ethanol/glycerol metabolites in agitated process was 29 and 27 h, and in static 47 and 45 h, respectively. For acetic fermentation, the kinetics parameters were medium time of 39.9 h, acetic acid yield of 53.1% and acetic acid productivity of 0.216 g/Lh. Wines from agitated/static process presented 5.73 and 6.81% (v/v) of alcohol content, respectively. Wine obtained by the static process presented higher concentrations of volatile compounds. The vinegar showed 49.2 g/L of acetic acid and the esters concentrations were higher than in wine. The wine and vinegar minerals were consistent with amount observed in the pulp, with an increase in sulphur concentration after alcoholic fermentation and decrease after acetic fermentation. Products showed chemical and composition of sensory and nutritional interest.
ARTICLE | doi:10.20944/preprints202110.0339.v1
Subject: Medicine & Pharmacology, Anesthesiology Keywords: Drosophila melanogaster; TBI; obesity; volatile anesthetics; isoflurane; sevoflurane; preconditioning; mortality; toxicity
Online: 25 October 2021 (10:28:33 CEST)
We tested the hypothesis that obesity influences the pharmacodynamics of volatile general anesthetics (VGAs) by comparing effects of anesthetic exposure on mortality from traumatic brain injury (TBI) in lean and obese Drosophila melanogaster. We induced TBI with a High-Impact Trauma device. Starvation-selection over multiple generations resulted in an obese phenotype (SS flies). Fed flies served as lean controls (FC flies). Adult (1-7 day old) SS and FC flies were exposed to equianesthetic doses of isoflurane or sevoflurane either before or after TBI. The principal outcome was percent mortality 24 hours after injury, expressed as the Mortality Index at 24 hours (MI24). TBI resulted in lower MI24 in FC than in SS flies (21 (2.35) and 57.8 (2.14), respectively n= 12, p=0.0001). Preexposure to isoflurane or sevoflurane preconditioned FC flies to TBI reducing the risk of death to 0.53 [0.25 to 1.13] and 0.82 [0.43 to 1.58], respectively, but had no preconditioning effect in SS flies. Postexposure to isoflurane or sevoflurane increased the risk of death in SS flies. Only postexposure to isoflurane increased the risk in FC flies (1.39 [0.81 to 2.38]). Thus, obesity affects the pharmacodynamics of VGAs, thwarting the preconditioning effect of isoflurane and sevoflurane in TBI.
ARTICLE | doi:10.20944/preprints202109.0309.v1
Subject: Biology, Plant Sciences Keywords: Trichoderma atroviride; volatile organic compounds; tomato; biostimulation; biocontrol; Fusarium wilt disease
Online: 17 September 2021 (12:03:42 CEST)
The promotion of plant growth and suppression of plant disease using beneficial microorganisms is considered an alternative to the application of chemical fertilizers or pesticides in the field. In this study, a coconut-scented antagonistic Trichoderma strain LZ42, previously isolated from Genoderma lucidum-cultivated soil, was investigated for biostimulatory and biocontrol functions in tomato seedlings. Morphological and phylogenetic analyses suggested that strain LZ42 is closely related to T. atroviride. Tomato plants showed increased aerial and root dry weights in greenhouse trials after treatment with T. atroviride LZ42 formulated in talc, indicating the biostimulatory function of this fungus. T. atroviride LZ42 effectively suppressed Fusarium wilt disease in tomato seedlings, with an 82.69% control efficiency, which is similar to that of fungicide treatment. The volatile organic compounds (VOCs) emitted by T. atroviride LZ42 were found to affect the primary root growth direction and promote the root growth of tomato seedlings in root Y-tube olfactometer assays. The fungal VOCs from T. atroviride LZ42 were observed to significantly inhibit F. oxysporum in a sandwiched Petri dish assay. SPME-GC-MS analysis revealed several VOCs emitted by T. atroviride LZ42; the dominant compound was tentatively identified as 6-pentyl-2H-pyran-2-one (6-PP). 6-PP exhibited a stronger ability to influence the direction of the primary roots of tomato seedlings but not the length of the primary roots. The inhibitory effect of 6-PP on F. oxysporum was the highest among the tested pure VOCs, showing a 50% effective concentration (EC50) of 5.76 μL mL-1 headspace. In conclusion, T. atroviride LZ42, which emits VOCs with multiple functions, is a promising agent for the biostimulation of vegetable plants and integrated management of Fusarium wilt disease.
ARTICLE | doi:10.20944/preprints202107.0668.v1
Subject: Chemistry, Analytical Chemistry Keywords: olive oil; quality; storage conditions; phenols; volatile compounds; E-2-Nonenal
Online: 29 July 2021 (15:27:35 CEST)
Abstract: Commercialization of extra virgin olive oil (EVOO) requires a best before date recom-mended at up to 24 months after bottling, stored under specific conditions. Thus, it is expected that the product retains its chemical properties and preserves its ‘extra virgin’ category. However, in-adequate storage conditions could alter the properties of EVOO. In this study, Arbequina EVOO was exposed to five storage conditions for up to one year to study the effects on the quality of the oil and the compounds responsible for flavor. Every 15 or 30 days, samples from each storage condition were analyzed determining physicochemical parameters, the profiles of phenols, volatile compounds, α-tocopherol and antioxidant capacity. Principal component analysis was utilized to better elucidate the relationships between composition of EVOOs and the storage conditions. EVOOs stored at -23 and 23 °C in darkness and 23 °C with light, differed from the oils stored at 30 and 40 °C in darkness. The former were associated with higher quantity of non-oxidized phenolic compounds and the latter with higher elenolic acid, oxidized oleuropein and ligstroside derivatives, which also increased with storage time. E-2-Nonenal (detected at trace levels in fresh oil) was selected as a marker of the degradation of Arbequina EVOO quality over time, with significant linear regressions identified for the storage conditions at 30 and 40 °C. Therefore, early oxidation in EVOO could be monitored by measuring E2-Nonenal levels.
REVIEW | doi:10.20944/preprints201811.0056.v1
Subject: Chemistry, Food Chemistry Keywords: white wine; volatile compounds; sensorial characteristics; oak; alternative woods; barrels; chips
Online: 2 November 2018 (12:40:47 CET)
Ageing wine is a commonly practice used in winemaking since the quality and sensory profile increase due to the extractable compounds coming from wood by means of barrels or chips. The quantitative and qualitative compounds from wood depend on the species, its origins and the treatments applied in cooperages. Traditionally, oak wood species are most often used in cooperage, specifically Quercus alba, Known as American oak and Q. robur and Q. petraea both known as French oak. However, although this stage is very common for red wines, its use is still restricted in the case of white wines. However, this topic is particularly interesting, since due to the sensorial benefits of wood contact, the option for ageing white wines in barrels or chips is increasingly and widely chosen by winemakers. This review compiles the novel strategies applied to white wines by means of wood contact in the last years with the aim to increase wine quality and sensorial features.
REVIEW | doi:10.20944/preprints201810.0691.v1
Subject: Earth Sciences, Environmental Sciences Keywords: Chemical sensors; E-nose; Environmental monitoring; Seawater; Sensors; Volatile Organic Compounds
Online: 29 October 2018 (14:36:11 CET)
Electronic Nose (eNose) systems are particularly appreciated for their portability, usability, relative low cost and real-time or near real-time response. Their application finds space in several domains, including environmental monitoring. Within this field, marine monitoring is of particular scientific relevance due to the fragility of this specific environment, daily threatened by human activities that can potentially bring to catastrophic and irreversible consequences on marine wildlife. Under such considerations, a systematic review, complying with the PRISMA guidelines, was conducted covering the period up to October 15, 2018, in PubMed, ScienceDirect and Google Scholar. Despite the relatively low number of articles published on this specific topic and the heterogeneity of the technological approaches employed, the results obtained by the various groups highlight the positive contribution eNose has given and can provide in near future for the monitoring and safeguarding of this delicate environment.
ARTICLE | doi:10.20944/preprints201809.0304.v1
Subject: Materials Science, Nanotechnology Keywords: Zeolites; ZK-4 zeolite; Microspheres; Molecular decontamination; Volatile Organic Compounds (VOCs)
Online: 17 September 2018 (11:29:58 CEST)
Binderless zeolite macrostructures in the form of ZK-4 microspheres were prepared using anion exchange resin beads as shape directing macrotemplates. The particles were synthesized under hydrothermal conditions at different temperatures and treatment times. The influence of the different synthesis parameters was investigated by X-ray diffraction, scanning electron microscopy, fluorescence X, nitrogen adsorption measurements and 29Si solid NMR. Fully crystalline spheres similar in size and shape to the original resin beads were obtained by a hydrothermal treatment at the highest temperatures (150 - 180 °C) for a short treatment time of 24 h. The synthesized microspheres showed to be promising in the molecular decontamination of Volatile Organic Compounds (VOCs).
ARTICLE | doi:10.20944/preprints201804.0013.v2
Subject: Engineering, Electrical & Electronic Engineering Keywords: temperature modulation; gas sensors; volatile organic compounds; electronic nose; conditioning circuit
Online: 23 April 2018 (11:47:33 CEST)
This paper consists of the design and implementation of a simple conditioning circuit to optimize the electronic nose performance, where a temperature modulation method was applied to the heating resistor to study the sensor’s response and confirm whether they are able to make the discrimination when exposed to different volatile organic compounds (VOC’s). This study was based on determining the efficiency of the gas sensors with the aim to perform an electronic nose, improving the sensitivity, selectivity and repeatability of the measuring system, selecting the type of modulation (e.g., pulse width modulation) for the analytes detection (i.e., Moscatel wine samples (2% of alcohol) and ethyl alcohol (70%)). The results demonstrated that by using temperature modulation technique to the heating resistors, it is possible to realize the discrimination of VOC’s in fast and easy way through a chemical sensors array. Therefore, a discrimination model based on principal component analysis (PCA) was implemented to each sensor, with data responses obtaining a variance of 94.5% and accuracy of 100%.
ARTICLE | doi:10.20944/preprints201711.0145.v1
Subject: Engineering, Other Keywords: ultraviolet radiation; bioaerosol; formaldehyde; total volatile organic compounds; indoor air quality
Online: 22 November 2017 (10:26:40 CET)
This study examined the use of high dosages of ultraviolet germicidal irradiation (UVGI) (253.7 nm) to deal with various concentrations of air pollutants, such as formaldehyde (HCHO), total volatile organic compounds (TVOC), under various conditions of humidity. We also estimated the emission of ozone as a secondary pollutant of UVGI as treatment. A number of irradiation methods were applied for various durations in field studies to examine the efficiency of removing HCHO, TVOC, bacteria, and fungi. The removal efficiency of air pollutants (HCHO and bacteria) through long-term exposure to UVGI appears to increase with time. The effects on TVOC and fungi concentration were insignificant in the first week; however, improvements were observed in the second week. No differences were observed among the various irradiation methods in this study regarding the removal of HCHO and TVOC; however significant differences were observed in the removal of bacteria and fungi.
ARTICLE | doi:10.20944/preprints201707.0042.v1
Subject: Medicine & Pharmacology, Nursing & Health Studies Keywords: surgical smoke; volatile organic compounds (VOCs); health risk assessment (HRA); carcinogenic
Online: 17 July 2017 (07:40:18 CEST)
Surgical smoke is produced by energy-based surgical instruments. The airborne volatile organic compounds (VOCs) from surgical smoke may have potential health risk. This study aimed to evaluate the evidence for the harmful effects on the operating theater staff. An internationally recognized evaluation model of health risk assessment (HRA) was adapted to preliminarily assess the health risks caused by VOCs in surgical smoke. Results of HRA indicated that non-carcinogenic risk indexes of VOCs did not exceed one, indicating that these pollutants didn't cause significant non-carcinogenic harm to the health of the operating theater staff. But the cancer risk indexes exposed to formaldehyde and benzene all exceed 10-5, which was higher than the suggested value of USEPA (10-6) and might cause potential harm to the health of the operating theater staff. Long-term exposure of such surgical smoke will be harmful to the health of the operating theater staff and have a great risk of cancer.
ARTICLE | doi:10.20944/preprints202212.0586.v1
Subject: Medicine & Pharmacology, Psychiatry & Mental Health Studies Keywords: Anxiety; Biogenic volatile organic compounds; Forest therapy; Monoterpenes; α-Pinene; Propensity matching.
Online: 31 December 2022 (08:04:39 CET)
Immersive experiences in green areas and particularly in forests have long been known to produce beneficial effects for human health. However, the exact determinants and mechanisms leading to healthy outcomes remain to be elucidated. The purpose of this study was to investigate whether inhaling plant-emitted biogenic volatile compounds, namely monoterpenes (MTs), can produce specific effects on anxiety. Data from 505 subjects participating in 39 structured forest therapy sessions in different Italian sites, were collected. Monoterpenes air concentration was measured at each site. STAI State questionnaires were administered before and after the sessions as a measure of anxiety. A propensity score matching analysis was then performed, considering an above-average exposure to inhalable air MTs as the treatment: the estimated effect was -1.28 STAI-S points (95% C.I. -2.51 to -0.06, p = 0.04), indicating that the average effect of exposure to high MT air concentrations during forest therapy sessions is to decrease anxiety.
ARTICLE | doi:10.20944/preprints202207.0063.v1
Subject: Biology, Animal Sciences & Zoology Keywords: Native shrubs; In vitro fermentation; volatile fatty acids; greenhouse gases; hill country
Online: 5 July 2022 (07:40:50 CEST)
Information on the nutritive value and in vitro fermentation characteristics of native shrubs in New Zealand is scant. This is despite their potential as alternatives to exotic trees and shrubs for sup-plementary fodder, and mitigation of greenhouse gas and soil erosion on hill country sheep and beef farms. The objectives of this study were to measure the in vitro fermentation gas production, predict parameters of in vitro fermentation kinetics and to estimate in vitro fermentation of volatile fatty acids (VFA), microbial biomass (MBM) and greenhouse gases of four native shrubs (Coprosma robusta, Griselinia littoralis, Hoheria populnea and Pittosporum crassifolium) and an exotic fodder tree species, Salix schwerinii. Total in vitro gas production was higher (p<0.05) for natives than S. schwerinii. Prediction using the single pool model resulted in biologically incorrect negative in vitro total gas production from the immediately soluble fraction of the native shrubs. However, the dual pool model better predicted in vitro total gas production and was in alignment with measured in vitro fermentation end products. In vitro VFA and greenhouse gas production from fermentation of leaf and stem material were higher (p<0.05), and MBM lower (p<0.05), for native shrubs com-pared to S. schwerinii. The lower in vitro total gas production, VFA and greenhouse gases produc-tion, and higher MBM of S. schwerinii may be explained by the presence of condensed tannins (CT), although this was not measured and requires further study. In conclusion, results from this study suggests that when consumed by ruminant livestock, the browsable native shrubs can provide adequate energy and microbial protein, and that greenhouse gas production from these species is within ranges reported for typical New Zealand pastures.
ARTICLE | doi:10.20944/preprints201904.0316.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: leaf area index; cocoa beans; volatile compounds; artificial neural networks; VitiCanopy app
Online: 28 April 2019 (11:36:14 CEST)
Cocoa is an important commodity crop not only to produce one of the most complex products such as chocolate from the sensory perspective, but one that commonly grows in developing countries close to the tropics. This paper presents novel techniques applied using cover photography and a novel computer application (VitiCanopy) to assess the canopy architecture of cocoa trees in a commercial plantation in Queensland, Australia. From the cocoa trees monitored, pod samples were collected, fermented, dried and grinded to obtain the aroma profile per tree using gas chromatography. The canopy architecture data were used as inputs in an artificial neural network (ANN) algorithm and the aroma profile considering six main aromas as targets. The ANN model rendered high accuracy (R = 0.82; MSE = 0.09) with no overfitting. The model was then applied to a satellite image from the whole cocoa field studied to produce canopy vigor and aroma profile maps up to the tree-by-tree scale. The tool developed could aid significantly the canopy management practices in cocoa trees that have a direct effect on cocoa quality.
ARTICLE | doi:10.20944/preprints201901.0321.v2
Subject: Chemistry, Analytical Chemistry Keywords: SPME; Carboxen; volatile organic compounds; benzene; transport in porous media; COMSOL Multiphysics
Online: 23 April 2019 (06:24:45 CEST)
Experimental optimization of analytical methods based on solid-phase microextraction (SPME) is a complex and labor-intensive process associated with uncertainties. Using the theoretical basics of SPME and finite element analysis software for the optimization proved to be an efficient alternative. In this study, an improved finite element analysis-based model for SPME of volatile organic compounds (VOCs) by porous coatings was developed mainly focussing on the mass transport in coatings. Benzene and the Carboxen/polydimethylsiloxane (Car/PDMS) coating were used as the model VOC and a porous SPME coating, respectively. It has been established that in the coating, volumetric fractions of Carboxen, PDMS, and air are 33, 42 and 24%, respectively. Knudsen diffusion in micropores can slow down a mass transport of analytes in the coating. When PDMS was considered as the solid part of the coating, lower root-mean-square deviation of the modeling results from experimental data was observed. It has been shown that the developed model can be used to model the extraction of VOCs from air and water samples encountered in a typical SPME development method procedure. It was possible to determine system equilibration times and use them to optimize sample volume and Henry’s law constant. The developed model is relatively simple, fast, and can be recommended for optimization of extraction parameters for other analytes and SPME coatings. The diffusivity of analytes in a coating is an important property needed for improved characterization of existing and new SPME polymers and analytical method optimization.
ARTICLE | doi:10.20944/preprints202110.0226.v1
Subject: Life Sciences, Biotechnology Keywords: kefir grains; red table grapes; kefir-like beverage; fed-batch fermentation; volatile compounds
Online: 15 October 2021 (14:04:51 CEST)
The aim of this work was to study the production of kefir-like beverage by fed-batch fermentation of red table grape juice at initial pHs of 3.99 (fermentation A) and 5.99 (fermentation B) with kefir grains during four repeated 24-h fed-batch subcultures. However, all kefir-like beverages (KLB) were characterized by low alcoholic grade (≤ 3.6%, v/v) and lactic and acetic acid concentrations. The beverages obtained from fermentation B had lower concentrations of sugars and higher microbial counts than the KLB obtained in fermentation A. In addition, the KLB from fermentation B were the most aromatic and had the highest contents in alcohols, esters, aldehydes and organic acids compared to the non-fermented juice and KLB from fermentation A. These results indicate the possibility of obtaining red table grapes KLB with their own distinctive aromatic characteristics and a high content in probiotic viable cells, contributing to the valorization of this fruit.
ARTICLE | doi:10.20944/preprints202105.0485.v1
Subject: Behavioral Sciences, Applied Psychology Keywords: anger; anxiety; confusion; depression; fatigue; forest therapy; mental health; vigor; volatile organic compounds
Online: 20 May 2021 (11:22:20 CEST)
Immersion in forest environments was shown to produce beneficial effects to human health, in particular psychophysical relaxation, so much that this practice is increasingly recognized as a form of integrative medicine. Limited evidence exists about both statistical significance and size of the effects conditioned on personal characteristics, as well as on the main external variables. The primary purpose of this study was to substantiate the very concept of forest therapy by means of the quantification and significance of the psychological effects, stratified by gender, age groups and place of residence. A preliminary qualitative analysis of the main determinants, in particular the method of conducting, the meteorological comfort and the concentration of volatile organic compounds in the forest atmosphere, was afforded. Seven forest therapy sessions were performed in late summer though early fall, resulting in 150 psychological self-assessment questionnaires administered before and after each session. The results were comparable or even better than others reported in the international literature. Moreover, preliminary evidence arose about different functionality towards specific psychological indexes conditioned at least on gender and age groups, as well as meteorological comfort, structured programs and, possibly, volatile organic compounds showed an impact on the outcomes.
ARTICLE | doi:10.20944/preprints202012.0608.v1
Subject: Engineering, Civil Engineering Keywords: air pollution control; air quality; environmental technology; advanced oxidation; odor; volatile organic compounds
Online: 24 December 2020 (08:58:47 CET)
Livestock production systems generate nuisance odor and gaseous emissions affecting local communities and regional air quality. Also, there are concerns about the occupational health and safety of farm workers. Proven mitigation technologies that are consistent with the socio-economic challenges of animal farming are needed. We have been scaling up the photocatalytic treatment of emissions from lab-scale, aiming at farm-scale readiness. In this paper, we present the design, testing, and commissioning of a mobile laboratory for on-farm research and demonstration of performance in real farm conditions. The mobile lab is capable of treating up to 1.2 m3·s-1 of air with TiO2-based photocatalysis and adjustable UV-A dose based on LED lamps. We summarize the main technical requirements, constraints, approach, and performance metrics for the mobile laboratory, such as the effectiveness (measured as the percent reduction) and cost of photocatalytic treatment of air. The commissioning of all systems with standard gases resulted in ~9% and 34% reduction of NH3 and butan-1-ol, respectively. We demonstrated that as the percent reduction of standard gases increased with increased light intensity and treatment time. These results show that the mobile laboratory was ready for on-farm deployment and evaluating the effectiveness of UV treatment.
REVIEW | doi:10.20944/preprints202002.0198.v1
Subject: Medicine & Pharmacology, Other Keywords: mild virus-infected flu; home-based treatment; inhalation of volatile chemicals; onion; garlic
Online: 15 February 2020 (14:38:20 CET)
Virus-infected Flu is a common disease. To date, no specific drugs are available to manage the symptoms of cough, headache and sputum production. An alternative Chinese herb medicine is introduced for virus-infected Flu or similar infection. Before hospitalization, some of patients may scare for cross-infection with mild symptoms or hardly go to hospital if encountered a temporary lockdown or quarantine. Some Chinese practice self-treatment of cough, headache and sputum production by inhalation of volatile chemicals from onion and garlic. Author used to take the same alternative approach of inhalation of onion, garlic or scallions for self-treatment when suffered virus caused flu with cough, headache and sputum production at onset disease. In this article, the biomedical effects of onion and garlic are reviewed. To help patients with mild symptoms of virus infected Flu, a simple home-based treatment was suggested to self-treatment because of temporary isolation and hardly going to hospitalization. The alternative approach may also suggest for some mild virus infected respiratory diseases caused by virus at onset disease.
ARTICLE | doi:10.20944/preprints201812.0353.v1
Subject: Engineering, Energy & Fuel Technology Keywords: agroindustrial waste; alperujo and orujo; rotary dryer emissions; volatile organic compounds; biomass drying
Online: 29 December 2018 (02:39:58 CET)
In the industrial production of olive oil, both solid wastes and those produced from their incineration are a serious environmental problem since only 20% w/w of the fruit becomes oil and the rest is waste, mainly orujo and alperujo. A key aspect to transform these wastes into an important source of energy such as pellets is to recognize the most appropriate time of the year for waste drying, with the objective of minimizing the environmental impact of the volatile compounds contained in the waste. In this work, the emissions produced during thermal-mechanical drying were studied along a period of six months of waste storage in which alperujo and orujo were stored in open containers under uncontrolled environmental conditions. The studied emissions were produced when both wastes were dried in a pilot rotary drying trommel at 450ºC to reduce their initial humidity of around 70-80% w/w to 10-15% w/w. Results indicated that when the storage time of the wastes in uncontrolled environments increases, the emission of odorant compounds during drying also increases as a consequence of the biological and chemical processes occurring in the containers during waste storage. The main odorant VOCs were quantified monthly for six months at the outlet of the drying trommel. It was determined that the drying of this type of waste can be carried out properly until the third month of storage. Afterwards, the concentration of most VOCs produced widely exceeded the odor thresholds of selected compounds.
ARTICLE | doi:10.20944/preprints201807.0313.v1
Subject: Chemistry, Analytical Chemistry Keywords: elephant dung coffee; volatile compound; discriminant marker; SHS GC–MS; chemometrics; coffee authentication
Online: 17 July 2018 (15:02:03 CEST)
Elephant dung coffee (Black Ivory Coffee) is a special Thai coffee produced from Arabica coffee cherries consumed by Asian elephants and collected from their feces. In this work, elephant dung coffee and controls were analyzed using static headspace gas chromatography hyphenated with mass spectrometry (SHS GC–MS), and chemometric approaches were applied for multivariate analysis and the selection of marker compounds that are characteristic of the coffee. Seventy-eight volatile compounds belonging to 13 chemical classes were tentatively identified, including 6 alcohols, 5 aldehydes, one carboxylic acid, 3 esters, 17 furans, one furanone, 13 ketones, 2 oxazoles, 4 phenolic compounds, 14 pyrazines, one pyridine, 8 pyrroles and 3 sulfur-containing compounds. Moreover, four potential discriminant markers of elephant dung coffee, including 3-methyl-1-butanol, 2-methyl-1-butanol, 2-furfurylfuran and 3-penten-2-one were established. The proposed method may be useful for elephant dung coffee authentication and quality control.
ARTICLE | doi:10.20944/preprints201803.0094.v2
Subject: Earth Sciences, Atmospheric Science Keywords: odor; volatile organic compounds; environmental analysis; air sampling; simultaneous chemical and sensory analysis; prairie verbena; prehensile-tailed porcupine; Virginia pepperweed
Online: 28 July 2021 (10:28:11 CEST)
Solving environmental odor issues can be confounded by many analytical, technological, and socioeconomic factors. Considerable know-how and technologies can fail to properly identify odorants responsible for the downwind nuisance odor and mitigate it for the affected citizenry. We propose enabling solutions to environmental odor issues by utilizing troubleshooting techniques developed for the food, beverage, and consumer products industries. We showed that the downwind odorant impact-priority ranking process can be definable and relatively simple. The initial challenge is the prioritization of environmental odor character from the perspective of the impacted citizenry downwind. In this research, we aim at summarizing three natural models of the rolling unmasking effect (RUE) and discuss them more systematically in the context of the proposed downwind environmental odor prioritization approach. Regardless of the size and reach of an odor source, a simplification of odor character and composition typically develops with downwind dilution. The extreme odor simplification-upon-dilution was demonstrated for two plant varieties, prairie verbena and Virginia pepperweed. Their downwind odor frontal boundaries were dominated by single, character-defining odorants; p-cresol-dominated ‘barnyard’ odor, and benzyl mercaptan-dominated ‘burnt match’ odor, respectively. The P.T. porcupine downwind odor frontal boundary was dominated by two potent, character-defining odorants: (1) ‘onion’/‘body odor’ odorant #1 and (2) ‘onion’/‘grilled’ odorant #2. In contrast with their downwind boundary simplicities, each odor source presented considerable compositional complexity and composite character difference near the source. The proposed RUE approach’s ultimate significance is the illustration of naturally occurring phenomena that explain why some environmental odors and their sources can be challenging to identify and mitigate using the analytical only approach (focused on compound identities and concentrations). These approaches rarely move beyond comprehensive lists of compounds being emitted by the source.
REVIEW | doi:10.20944/preprints202106.0040.v1
Subject: Medicine & Pharmacology, Allergology Keywords: Anesthetic drugs and techniques, opioids, propofol, volatile agent, breast cancer, cancer recurrence, Biomarkers, miRNA.
Online: 1 June 2021 (15:06:42 CEST)
This document summarizes the evidence currently available about the effects of the anesthetic agents and techniques used in primary cancer surgery and long-term oncologic outcomes, and the biomolecular mechanisms involved in their interaction..
ARTICLE | doi:10.20944/preprints202103.0045.v1
Subject: Engineering, Civil Engineering Keywords: air pollution control; air quality; volatile organic compounds; odor; environmental technology; advanced oxidation; UV
Online: 2 March 2021 (09:08:29 CET)
It is essential to mitigate gaseous emissions that result from poultry and livestock production to increase industry sustainability. Odorous volatile organic compounds (VOCs), ammonia (NH3), hydrogen sulfide (H2S), and greenhouse gases (GHGs) have detrimental effects on the quality of life in rural communities, the environment, and climate. This study's objective was to evaluate the photocatalytic UV treatment of gaseous emissions of odor, odorous VOCs, NH3, and other gases (GHGs, O3 – sometimes considered as by-products of UV treatment) from stored swine manure on a pilot-scale. The manure emissions were treated in fast-moving air using a mobile lab equipped with UV-A and UV-C lights and TiO2-based photocatalyst. Treated gas airflow (0.25 to 0.76 m3/s) simulates output from a small ventilation fan in a barn. Through controlling the light intensity and airflow, UV dose was tested for techno-economic analyses. The treatment effectiveness depended on the UV dose and wavelength. Under UV-A (367 nm) photocatalysis, the percent reduction of targeted gases was up to i) 63% of odor, ii) 51%, 51%, 53%, 67%, and 32% of acetic acid, propanoic acid, butanoic acid, p-cresol, and indole, respectively, iii) 14% of nitrous oxide (N2O), iv) 100% of O3, and 26% generation of CO2. Under UV-C (185+254 nm) photocatalysis, the percent reductions of target gases were up to i) 54% and 47% for p-cresol and indole, respectively, ii) 25% of N2O, iii) 71% of CH4, and 46% & 139% generation of CO2 & O3, respectively. The results proved that the UV technology was sufficiently effective in treating odorous gases, and the mobile lab was ready for farm-scale trials. The UV technology can be considered for the scaled-up treatment of emissions and air quality improvement inside livestock barns.
ARTICLE | doi:10.20944/preprints201809.0362.v1
Subject: Chemistry, Analytical Chemistry Keywords: solid-phase microextraction; air sampling; air analysis; volatile organic compounds; COMSOL; time-weighted average
Online: 19 September 2018 (04:08:14 CEST)
Determination of time-weighted average (TWA) concentrations of volatile organic compounds (VOCs) in air using solid-phase microextraction (SPME) is advantageous over other sampling techniques, but is often characterized by insufficient accuracies, particularly at longer sampling times. Experimental investigation of this issue and disclosing the origin of the problem is problematic and often not practically feasible due to high uncertainties. This research is aimed at developing the model of TWA extraction process and optimization of TWA air sampling by SPME using finite element analysis software (COMSOL Multiphysics). It was established that sampling by porous SPME coatings with high affinity to analytes is affected by slow diffusion of analytes inside the coating, an increase of analytes concentrations in the air near the fiber tip due to equilibration, and eventual lower sampling rate. The increase of a fiber retraction depth (Z) resulted in better recoveries. Sampling of studied VOCs using 23-ga Car/PDMS assembly at maximum possible Z (40 mm) was proven to provide more accurate results. Alternative sampling configuration based on 78.5 x 0.75 mm i.d. SPME liner was proven to provide similar accuracy at improved detection limits. Its modification with the decreased internal diameter from the sampling side should provide even better recoveries. The developed model offers new insight into optimization of air and gas sampling using SPME.
Subject: Engineering, Other Keywords: volatile organic compounds; air quality monitoring; metal oxide sensor; predictive mathematical model; gas composition estimation
Online: 29 March 2021 (16:20:16 CEST)
Monitoring volatile organic compounds (VOCs) places a crucial role in environmental pollutants control and indoor air quality. In this study, a metal-oxide (MOx) sensor detector (used in a commercially available monitor) was employed to delineate the composition of air containing three common VOCs (ethanol, acetone and hexane) under various concentrations. Experiments with a single component and double components were conducted to investigate how the solvents interact with the metal oxide sensor. The experimental results revealed that the affinity between VOC and sensor was in the following order: acetone > ethanol > n-hexane. A mathematical model was developed, based on the experimental findings and data analysis, to convert the output resistance value of the sensor into concentration values, which in turn can be used to calculate a VOC-based air quality index. Empirical equations were established based on inferences of vapor composition versus resistance trends, and on an approach of using original and diluted air samples to generate two sets of resistance data per sample. The calibration of numerous model parameters allowed matching simulated curves to measured data. As such, the predictive mathematical model enabled quantifying not only the total concentration of sensed VOCs, but also estimating the VOC composition. This first attempt to obtain semi-quantitative data from a single MOx sensor, despite remaining selectivity challenges, is aimed at expanding the capability of mobile air pollutants monitoring devices.
ARTICLE | doi:10.20944/preprints201807.0267.v1
Subject: Chemistry, Food Chemistry Keywords: Filuferru; spirit; distillation; grape marc; volatile compounds; copper; trace elements; GC-MS; ICP-MS; PCA
Online: 16 July 2018 (09:23:20 CEST)
Traditional Filuferru is an ancient spirit from Sardinia, Italy, usually obtained from the distillation of wine or grape marc. In this contribution, the results of the first chemical characterization of a wide number of craft Filuferru samples has been accomplished in terms of evaluation of the alcoholic strength, qualitative and quantitative GC-MS analysis of the volatile composition of the distillate, and its trace element composition by means a ICP-MS method. Both instrumental methods have been validated and applied on 21 craft samples of Filuferru, whereas one sample of commercial distillate has been analyzed for comparison purposes. Alcoholic strength ranged between 41.0 and 62.4% (v/v). Sixty volatile compounds were identified and ten of them have been quantified. Analogies and differences with Grappa (i.e. the Italian distilled spirit most close to Filuferru) have been highlighted in the qualitative and quantitative profile of this matrix. Often meaningful amounts of acetaldehyde, ethyl acetate, dietyl acetal and acetic acid were measured. Elemental analysis, performed on toxic, non-toxic elements and oligoelements, 18 in total, revealed a wide variability of concentrations in both analytes and samples. High concentrations of Cu are sometimes evidenced, likely caused by losses from the distillation apparatus. The principal components analysis (PCA) allowed the differentiation of the ten volatile compounds quantified in two groups: the former, described mainly by PC1, constituted by acetic acid, ethyl acetate, dietyl acetal and acetaldehyde, and the second, described by PC2, constituted by 1-propanol, 2-methyl-1-propanol, the two coeluiting isomers 2-methyl-1-butanol and 3-methyl-1-butanol,1-hexanol, 2-phenylethanol and 2,3-butanediol. Data obtained may be useful in order to establish a regulation for the production of high-quality traditional Filuferru from Sardinia.
REVIEW | doi:10.20944/preprints202211.0282.v1
Subject: Physical Sciences, Optics Keywords: Environmental monitoring; optical waveguide; optical fiber; photonic sensors; gas sensing; water quality monitoring; volatile organic compounds
Online: 15 November 2022 (08:56:24 CET)
Environmental monitoring is an important topic and serves a vibrant scientific role by revealing long-term trends that can lead to new knowledge and understanding. Globally, there is active development of photonic sensors incorporating multidisciplinary research. The ultimate objective is to develop small, low-cost, sensitive, selective, quick, durable, remote-controllable sensors that are resistant to electromagnetic interference. Different photonic sensor designs and advances in photonic frameworks have shown the possibility to realize these capabilities. In this review paper, the latest developments in the field of optical waveguide and fiber-based sensors which can serve for environmental monitoring are discussed. Several important topics such as toxic gas, water quality, indoor environment, and natural disaster monitoring are reviewed.
ARTICLE | doi:10.20944/preprints202108.0198.v1
Subject: Biology, Animal Sciences & Zoology Keywords: depolymerizing enzyme; debranching enzyme; xylanase; arabinofuranosidase; feruloyl esterase; arabinoxylan; digestion; growth performance; volatile fatty acid; piglet
Online: 9 August 2021 (14:56:56 CEST)
This study was aimed to investigate the effect of xylan depolymerizing enzyme namely endo-xylanase (Xyn) combined with debranching enzymes namely arabinofuranosidase (Afd) and feruloyl esterase (FE) on digestion, growth performance and intestinal volatile fatty acid profile of piglets. The in vitro experiments were firstly conducted to examine the enzymological properties of Xyn, Afd and FE, the synergy among these enzymes, together with the effect of combination of these enzymes on digestion of piglet diet. The in vivo experiment was then implemented by allocating 270 35-d-old postweaning piglets into 3 treatment groups: control group, Xyn group and (Xyn+Afd+FE) group. Each group had 6 replicates (15 piglets/replicate). The results revealed a satisfying thermostability and pH stability of Xyn, Afd and FE. Combination of Xyn, Afd and FE had a superiority (P < 0.05) over Xyn alone and its combination with Afd or FE in promoting degradation of different bran fibers rich in arabinoxylan (Abx). Treatment with combination of Xyn, Afd and FE had advantages over Xyn alone to induce increasing trends (P < 0.10) of in vitro digestibility of dietary nutrients (dry matter, crude protein, crude ash and gross energy) and piglet growth performance (average daily gain, final body weight and feed efficiency), concurrent with a reduction (P < 0.05) of diarrhea rate and increases (P < 0.05) in cecal acetic acid, butyric acid and total volatile fatty acids concentrations as well as pH value of piglets. Collectively, combination of Xyn, Afd and FE was efficient in benefiting degradation of Abx in brans, as well as improving digestion, growth performance and intestinal volatile fatty acid profile of piglets.
ARTICLE | doi:10.20944/preprints202106.0353.v1
Subject: Engineering, Automotive Engineering Keywords: Hazardous air pollutants; Medium-duty diesel trucks; Driving cycles; Non-methane volatile compound; Aldehydes; Polycyclic aromatic hydrocarbons
Online: 14 June 2021 (11:38:40 CEST)
Studies on the characteristics of hazardous air pollutants (HAPs) in the emissions of medium-duty diesel trucks are significantly insufficient compared to that on heavy-duty trucks. This study investigates the characteristics of regulated pollutants and HAPs such as volatile organic compounds (VOCs), aldehydes, and polycyclic aromatic hydrocarbons (PAHs), and estimates non-methane hydrocarbon (NMHC) speciation in the emissions of medium-duty diesel trucks. Ten medium-duty diesel trucks conforming to Euros 5 and 6 were tested for worldwide harmonized light duty driving test cycle (WLTC), new European driving cycle (NEDC), constant volume sampler (CVS)-75, and National Institute of Environmental Research (NIER)-9 using a chassis dynamometer. CO and NMHC emissions were the highest in the NEDC because of its longer low-speed driving time. NOx emissions were the highest in WLTC owing to the influence of thermal NOx in the high-speed phase. Alkanes dominated non-methane volatile compound (NMVOC) emissions owing to the low reaction of the diesel oxidation catalyst. After-treatment system, driving, and engine conditions influenced the individual components of NMVOC emissions. Formaldehyde emissions were the highest among aldehydes irrespective of driving cycles. By sampling the particle-phase of PAHs, we detected benzo(k)fluoranthene and benzo(a)pyrene and estimated the concentrations of the gas-phase PAHs with models to obtain the total PAH concentrations. The toxic equivalency quantities of benzo(k)fluoranthene and benzo(a)pyrene from NIER-9 (cold) for both Euro 5 and Euro 6 vehicles were more than five times higher than that of NIER (hot) and NEDC. In the case of NMHC speciation, formaldehyde emissions were the highest in all the driving cycles. Formaldehyde and benzene must be controlled in the emissions of medium-duty diesel trucks to reduce their health threats. The results of this study will aid in establishing a national emission inventory system for HAPs of mobile sources in Korea.
ARTICLE | doi:10.20944/preprints201911.0246.v1
Subject: Life Sciences, Biochemistry Keywords: bioactive compounds; forest air; forest bathing; forest therapy; hiking trails; human health; monoterpenes; stress; volatile organic compounds
Online: 21 November 2019 (04:19:17 CET)
Forest healing effects are increasingly valued for their contribution to human psychological and physiological health, motivating further advances aimed at improving the knowledge of the relevant forest resources. Biogenic volatile organic compounds, emitted by the plants and accumulating in the forest atmosphere, are essential contributors to the forest healing effects, and represent the focus of this study. Using a photoionization detector, we investigated the high frequency variability, in time and space, of the concentration of total volatile organic compounds, on a hilly site, as well as along forest paths and long hiking trails on Italian northern Apennines. The scale of concentration variability was found to be comparable to absolute concentration levels, within time scales of less than one hour, and spatial scales of several hundred meters. During daylight hours, the concentration peaked from noon to early afternoon, followed by early morning, with lowest levels in late afternoon. Based on a conceptual model, these results were related to meteorological variables, including the atmospheric vertical stability profile. Moreover, preliminary evidence pointed to higher concentration of volatile organic compounds in forests dominated by conifer trees, in comparison with pure beech forests.
REVIEW | doi:10.20944/preprints201804.0060.v1
Subject: Materials Science, Surfaces, Coatings & Films Keywords: volatile renewable resources; microbial infection; secondary plant metabolites; antimicrobial essential oils; biologically-active polymers; plasma-assisted technique
Online: 5 April 2018 (03:32:08 CEST)
The persistent issue of bacterial and fungal colonization of artificial implantable materials and decreasing efficacy of conventional systemic antibiotics used to treat implant-associated infections has led to the development of a wide range of antifouling and antibacterial strategies. This article reviews one such strategy where inherently biologically active renewable resources, i.e. secondary plant metabolites (SPMs) and their naturally occurring combinations (i.e. essential oils) are used for surface functionalization and synthesis of polymer thin films. With a distinct mode of antibacterial activity, broad spectrum of action and diversity of available chemistries, secondary plant metabolites present an attractive alternative to conventional antibiotics. However, their conversion from liquid to solid phase without significant loss of activity is not trivial. Using select examples, this article shows how plasma techniques provide a sufficiently flexible and chemically reactive environment to enable the synthesis of biologically-active polymer-coatings from volatile renewable resources.
ARTICLE | doi:10.20944/preprints201907.0023.v1
Subject: Biology, Ecology Keywords: plant defense; herbivory; mechanical wounding; oral secretions; induced volatiles; SpitWorm; MecWorm; Phaseolus lunatus; Spodoptera littoralis; volatile organic compounds
Online: 1 July 2019 (16:08:11 CEST)
Induction of jasmonate-mediated plant defense against insect herbivory is initiated by a combination of both, mechanical wounding and chemical factors. In order to study both effects independently on plant defense induction, SpitWorm, a computer-controlled device which mimics the damage pattern of feeding insect larvae on leaves and, in addition, can apply oral secretions (OS) or other solutions to the ‘biting site’ during ‘feeding’, was developed and evaluated. The amount of OS left by a Spodoptera littoralis larva during feeding on Phaseolus lunatus (lima bean) leaves was estimated by combining larval foregut volume, biting rate, and quantification of a fluorescent dye injected into the larvae’s foregut prior to feeding. For providing OS amounts by SpitWorm equivalent to larval feeding, dilution and delivery rate were optimized. The effectiveness of SpitWorm was tested by comparing volatile organic compounds (VOC) emissions of P. lunatus leaves treated with either SpitWorm, MecWorm or S. littoralis larvae. Identification and quantification of emitted VOCs revealed that SpitWorm induced a volatile bouquet that is qualitatively and quantitatively similar to herbivory. Additionally, RT-qPCR of four jasmonic acid responsive genes showed that SpitWorm, in contrast to MecWorm, induces the same regulation pattern as insect feeding. Thus, SpitWorm mimics insect herbivory almost identical to real larvae feeding.
Subject: Chemistry, Analytical Chemistry Keywords: Amomum villosum Lour.; Amomum villosum Lour. var. xanthioides T. L.Wu et Senjenis; GC-MS; Chemometric Techniques; volatile oil
Online: 1 April 2019 (08:30:57 CEST)
Fructus Amomi (FA) is usually regarded as the dried ripe fruits of Amomum villosum Lour. (FAL) or Amomum villosum Lour. var. xanthioides T. L.Wu et Senjenis (FALX) However, FAL, which always has a much higher price because of its better quality, is confused with FALX in the market. As volatile oil is the main constituent of FA, a strategy of chromatography-mass spectrometry (GC-MS) and chemometric approches was applied to compare the chemical composition of FAL and FALX. The results showed that the oil yield of FAL was significantly higher than that of FALX. Total ion chromatograph (TIC) showed that cis-nerolidol existed only in FALX. Bornyl acetate and camphor, could be considered as the most important ones in FAL and FALX respectively. Moreover, hierarchical cluster analysis (HCA) and principal component analysis (PCA) successfully distinguished the chemical constitutes of the volatile oils in FAL and FALX. Additionally, bornyl acetate, α-cadinol, linalool, β-myrcene, camphor, d-limonene, terpinolene and endo-borneol were selected as the potential markers for discriminating FAL and FALX by partial least squares discrimination analysis (PLS-DA). In conclusion, this present study first developed a scientific approach to separate FAL and FALX based on volatile oils by GC-MS combined with chemometric techniques.
COMMUNICATION | doi:10.20944/preprints202008.0297.v1
Subject: Chemistry, Analytical Chemistry Keywords: cat urine; odor mitigation; odor; volatile organic compounds; emission; indoor air quality, solid-phase microextraction; SPME; diffusion; Micrococcus luteus
Online: 13 August 2020 (08:51:58 CEST)
Urination on carpet and subflooring can develop into persistent and challenging to mitigate odor. Very little or no information is published on how these VOCs change over time when urine is deposited on the carpet covering a plywood-type subflooring. This research has investigated the VOCs emitted from carpet+subflooring (control), carpet+subflooring sprayed with water (control with moisture), and cat urine-contaminated carpet+subflooring (treatment) over time (day 0 and 15). In addition, the effect of popular cleaning products on VOCs emitted and evaluated their efficacy in eliminating those indoor odors over time (day 0 and 15). Carpet-subflooring with all treatments were also contaminated with Micrococcus luteus, nonmotile obligate aerobe commonly found in household dust, to observe the impact of the aerobe on carpet-subflooring VOCs emission. VOCs emitted from carpet+subflooring receiving different treatments were collected from headspace using solid-phase microextraction (SPME). The VOCs were analyzed using a multidimensional gas chromatography-mass spectrometer attached to an olfactometry (GC-MS-O). Many common VOCs were released from the carpet on day one and day fifteen, specifically from urine contamination. Cleaning products were effective in masking several potent odors of cat urine contaminated carpet VOCs on day one but unable to remove the odor appeared on day 15 in most cases.
Subject: Biology, Other Keywords: trichoderma atroviride; mycoparasitism; secondary metabolites; volatile organic compounds (VOCs); photoconidiation; fungi; 2-octanone; injury response; light response; fusarium oxysporum
Online: 11 December 2019 (04:55:05 CET)
Trichoderma atroviride is a strong necrotrophic mycoparasite antagonizing and feeding on a broad range of fungal phytopathogens. It further beneficially acts on plants by enhancing growth in root and shoot and inducing systemic resistance. Volatile organic compounds (VOCs) are playing a major role in all those processes. To date, T. atroviride IMI 206040 and T. atroviride P1 are among the most frequently studied T. atroviride strains and hence are used as model organisms to study mycoparasitism and photoconidiation. However, there are no studies available, which systematically and comparatively analyzed putative differences between these strains regarding their light-dependent behavior. We therefore explored the influence of light on conidiation and the mycoparasitic interaction as well as the light-dependent production of VOCs in both strains. Our data show that in contrast to T. atroviride IMI 206040 conidiation in strain P1 is independent of light. Furthermore, significant strain-and light-dependent differences in the production of several VOCs between the two strains became evident, indicating that T. atroviride P1 could be a better candidate for plant protection than IMI 206040.
ARTICLE | doi:10.20944/preprints202106.0393.v1
Subject: Life Sciences, Biochemistry Keywords: clear cell renal cell carcinoma (ccRCC); LOX-1 protein; volatile compounds (VOCs); prognostic biomarker; urine; gas chromatography mass spectrometer (GC/MS)
Online: 15 June 2021 (10:29:39 CEST)
Renal cell carcinoma (RCC) represents around 3% of all cancers, within which clear cell RCC (ccRCC) are the most common type (70–75%). The RCC disease regularly progresses asymptomatically and upon presentation is recurrently metastatic, so an early method of detection is necessary. The identification of one or more spe-cific biomarkers measurable in biofluids (i.e urine) by combined approaches could surely be appropriate for this kind of cancer, especially due to easy obtainability by non invasive method. OLR1 is a metabolic gene that encodes for the Lectin-like oxidized low-density lipoprotein re-ceptor-1 (LOX-1), implicated in inflammation, atherosclerosis, ROS and metabolic disor-der-associated carcinogenesis. Specifically, LOX-1 is clearly involved in tumor insurgence and progression of different human cancers. This work reports for the first time the presence of LOX-1 protein in ccRCC urine and its peculiar distribution in tumoral tissues. In parallel, urine samples headspace has been analyzed for the presence of the volatile compounds (VOCs) by SPME-GC/MS and gas sensor array. In particular, it was found by GC/MS analysis that 2-Cyclohexen-1-one,3-methyl-6-(1-methylethyl)- correlates with LOX-1 concentration in urine. Thus, the combined approach of VOCs analysis and protein quantification could led to promis-ing results in terms of diagnostic and prognostic potential for ccRCC tumor.
ARTICLE | doi:10.20944/preprints202103.0629.v1
Subject: Engineering, Civil Engineering Keywords: air pollution control; air quality; volatile organic compounds; nuisance smell; livestock agriculture; waste management; environmental technology; advanced oxidation; excimer; titanium dioxide
Online: 25 March 2021 (14:46:38 CET)
UV-A (ca. 365 nm wavelength, a.k.a. 'black light') photocatalysis has been investigated to comprehensively mitigate odor and selected air pollutants in the livestock environment. This study was conducted to confirm the performance of UV-A photocatalysis on the swine farm. The objectives of this research were to (1) scale-up of the UV-A photocatalysis treatment, (2) evaluate the mitigation of odorous gases from swine slurry pit, and (3) test different UV sources, (4) evaluate the effect of suspended particulate matter (PM), and (5) conduct preliminary economic analyses. We tested UV-A photocatalysis at a mobile laboratory-scale capable of treating ~0.2 - 0.8 m3·s-1 of barn exhaust air. The targeted gaseous emissions of barn exhaust air were significantly mitigated (p < 0.05) up to 40% reduction of measured odor; 63%, 44%, 32%, 40%, 66%, and 49% reduction of dimethyl disulfide, isobutyric acid, butanoic acid, p-cresol, indole, and skatole, respectively; 40% reduction of H2S; 100% reduction of O3; and 13% reduction of N2O. The PM mitigation effect was not significant. Formaldehyde levels did not change, and a 21% generation of CO2 was observed. The percent reduction of targeted gases decreased as the airborne PM increased. Simultaneous chemical and sensory analysis confirmed that UV-A treatment changed the overall nuisance odor character of swine barn emissions into weaker manure odor with 'toothpaste and 'mint' notes. The smell of benzoic acid generated in UV-A treatment was likely one of the compounds responsible for the less-offensive overall odor character of the UV-treated emissions. Results are needed to inform the design of a farm-scale trial, where the interior barn walls can be treated with the photocatalyst, and foul air will be passively treated as it moves through the barn.
ARTICLE | doi:10.20944/preprints202009.0614.v2
Subject: Engineering, Civil Engineering Keywords: air quality; air pollution; sustainable animal production; livestock and poultry; waste management; odor, ammonia; hydrogen sulfide; greenhouse gases; volatile organic compounds
Online: 26 October 2020 (09:33:12 CET)
Environmental impact associated with odor and gaseous emissions from animal manure is one of the challenges for communities, farmers, and regulatory agencies. Microbe-based manure additives treatments are marketed and used by farmers for mitigation of emissions. However, their performance is difficult to assess objectively. Thus, comprehensive, practical, and low-cost treatments are still in demand. We have been advancing such treatments based on physicochemical principles. The objective of this research was to test the effect of the surficial application of a thin layer (¼"; 6.3 mm) of biochar on the mitigation of gaseous emissions (as the percent reduction, % R) from swine manure. Two types of biochar were tested: highly alkaline and porous (HAP) biochar made from corn stover and red oak (RO), both with different pH and morphology. Three 30-day trials were conducted with a layer of HAP and RO (2.0 & 1.65 kg∙m-2, respectively) applied on manure surface, and emissions of ammonia (NH3), hydrogen sulfide (H2S), greenhouse gases (GHG), and odorous volatile organic compounds (VOCs) were measured. The manure and biochar type and properties had an impact on the mitigation effect and its duration. RO significantly reduced NH3 (19-39%) and p-cresol (66-78%). H2S was mitigated (16~23%), but not significantly for all trials. Significant (66~78%) reductions for p-cresol were observed for all trials. The phenolic VOCs had relatively high % R in most trials but not significantly for all trials. HAP reduced NH3 (4~21%) and H2S (2~22%), but not significantly for all trials. Significant % R for p-cresol (91~97%) and skatole (74~95%) were observed for all trials. The % R for phenol and indole ranged from (60~99%) & (29~94%) but was not significant for all trials. The impact on GHGs, isobutyric acid, and the odor was mixed with some mitigation and generation effects. However, larger-scale experiments are needed to understand how biochar properties and the dose and frequency of application can be optimized to mitigate odor and gaseous emissions from swine manure. The lessons learned can also be applicable to surficial biochar treatment of gaseous emissions from other waste and area sources.
ARTICLE | doi:10.20944/preprints202212.0521.v1
Subject: Materials Science, Nanotechnology Keywords: multi-modal sensing devices; PDAC; reduced graphene oxide; layer-by-layer deposition; temperature monitoring; relative humidity measurements; volatile organic compounds; electrochemical sensing
Online: 28 December 2022 (01:18:48 CET)
Precise monitoring of different environmental parameters and contaminations during food processing and storage is a key factor for maintaining its safety and nutritional value. Thus, developing reliable, efficient, cost-effective sensor devices for these purposes is of utmost importance. In this paper, we show that Poly-(diallyl-dimethylammonium chloride)/reduced Graphene oxide (PDAC/rGO) films produced by a simple Layer-by-Layer deposition can be effectively used to monitor temperature, relative humidity and the presence of volatile organic compounds as indicators for spoilage odors. At the same time, they show potential for electrochemical detection of organophosphate pesticide dimethoate. By monitoring the resistance/impedance changes during temperature and relative humidity variations or upon the exposure of PDAC/rGO films to methanol, good linear responses were obtained in the temperature range of 10-100 °C, 15-95 % relative humidity, and 35 ppm - 55 ppm of methanol. Moreover, linearity in the electrochemical detection of dimethoate is shown for the concentrations in the order of 102 µmol dm−3. The analytical response to different external stimuli and analytes depends on the number of layers deposited, affecting sensors’ sensitivity, response and recovery time, and long-term stability. The presented results could serve as a starting point for developing advanced multimodal sensor devices and sensor arrays with high potential for analytical applications in food safety and quality monitoring.
ARTICLE | doi:10.20944/preprints202203.0143.v1
Subject: Life Sciences, Cell & Developmental Biology Keywords: human pluripotent stem cells; human embryonic stem cells; human induced pluripotent stem cells; cellular metabolism; oxygen; self-renewal; pluripotency; differentiation; volatile organic compounds; Selected ion flow tube-mass spectrometry
Online: 10 March 2022 (10:23:46 CET)
Human pluripotent stem cells (hPSCs) have widespread potential biomedical applications. There is a need for large-scale in vitro production of hPSCs, and optimal culture methods are vital in achieving this. Physiological oxygen (2% O2) improves key hPSCs attributes, including genomic integrity, viability, and clonogenicity, however, its impact on hPSC metabolism remains un-clear. Here, Selected Ion Flow Tube-Mass Spectrometry (SIFT-MS) was used to detect and quantify metabolic Volatile Organic Compounds (VOCs) in the headspace of hPSCs and their differentiated progeny. hPSCs were cultured in either 2% O2 or 21% O2. Media was collected from cell cultures and transferred into glass bottles for SIFT-MS measurement. The VOCs acetaldehyde and dimethyl sulfide (DMS)/ethanethiol were significantly increased in undifferentiated hPSCs compared to their differentiating counterparts, and these observations were more apparent in 2% O2. Pluripotent marker expression was consistent across both O2 concentrations tested. Transcript levels of ADH4, ADH5, and CYP2E1, encoding enzymes involved in converting ethanol to acetaldehyde, were upregulated in 2% O2, and chemical inhibition of ADH and CYP2E1 decreased acetaldehyde levels in hPSCs. Acetaldehyde and DMS/ethanethiol may be indicators of altered metabolism pathways in physiological oxygen culture conditions. The identification of non-destructive biomarkers for hPSC characterization has the potential to facilitate large-scale in vitro manufacture for future biomedical application.