ARTICLE | doi:10.20944/preprints201909.0113.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: native yeast; biocontrol; fungal pathogens; VOCs
Online: 11 September 2019 (02:55:31 CEST)
Changes in consumer expectations have led to increasing demand for novel plant protection strategies, in order to reduce the application of chemical products, reduce the occurrence of new pests and the impact that all these actions generate in the environment. In recent years there have been numerous investigations related to biological control and the use of microorganisms as new control strategies. As part of integrated disease management, antagonistic microorganisms have been investigated lately and presented great interest. Such microorganisms can be applied in conventional and in organic farming as biological control agents (BCA). Many of these microorganisms are present in the microbial ecology generating interactive associations between surrounding microorganisms. For these reasons, it has become necessary to search new natural antimicrobial agents as alternatives to synthetic and chemical products. It has been discovered that there are microorganisms, particularly yeasts, that have antagonistic activity and different mechanisms of action, indicating that they could be interesting candidates for the development of BCA. Here, we evaluate the antagonist effect of four endophytic yeast, Cryptococcus antarcticus, Aureobasidium pullulans, Cryptococcus terrestris and Cryptococcus oeirensis over the growth of Botrytis cinerea, Monilinia laxa, Penicillium expansum and Geotrichum candidum in in vitro assays (inhibition zone diameter assay and confrontation assay).The results revealed that the four yeast strains evaluated showed antagonistic activity against the phytopathogens tested, suggesting that these yeasts produce compounds capable of inhibiting the growth of fungi and, depending on the assay, the evaluated antagonist-yeasts have differential biocontrolling-effect against the postharvest pathogens tested.
ARTICLE | doi:10.20944/preprints202011.0517.v1
Subject: Chemistry, Analytical Chemistry Keywords: titanium dioxide; oxidation; photocatalysis; VOCs mineralization; Langmuir-Hinshelwood
Online: 19 November 2020 (15:20:44 CET)
A jointed experimental and theoretical investigation pointing out new insights about the microscopic mechanism of the VOCs (volatile organic compounds) photocatalytic elimination by TiO2 has been done. Methane, hexane, isooctane, acetone and methanol have been photomineralized in a batch reactor. Values of K (adsorption constant on TiO2) and k (mineralization rate constant) of the five VOCs (treating the kinetic data through a Langmuir- Hinshelwood approach) have been determined. Recorded K and k values and performed theoretical calculations allowed us to suggest the involvement of an electron transfer step between the VOC and the hole, TiO2(h+), as the rate determining one.
ARTICLE | doi:10.20944/preprints202101.0010.v1
Subject: Chemistry, Analytical Chemistry Keywords: felinine; smell; odor; SPME; GC-MS-O; VOCs; feline
Online: 4 January 2021 (10:47:54 CET)
The association between human and cat (F. catus) is well known. This domestic animal is also known for its malodorous urine and feces. The complexity of the odorous urine and feces impacts human life by triggering the human sensory organ in a negative way. The objective of this research was to identify the volatile organic chemicals (VOCs) and associated odors in cat urine and feces using gas chromatography-mass spectrometry and simultaneous sensory analysis of fresh and aged samples. The solid-phase microextraction (SPME) technique was used to pre-concentrate the VOCs emitted from urine or feces samples. Twenty-one compounds were identified as emitted from fresh urine, whereas 64 compounds were emitted from fresh feces. A contrasting temporal impact was observed on the emission of VOCs for urine and feces. On aging, the emission increased to 36 detected chemicals for stale urine, whereas only 17 chemicals were detected in stale feces. Not all compounds were malodorous; some compounds had a pleasant hedonic smell to the human nose. Although trimethylamine, low molecular weight organic acids, and ketones were contributors to the odor to some extent, phenolic compounds and aromatic heterocyclic organic N compounds generated the most intense odors and substantially contributed to the overall malodor, as observed by this study. This work might be useful to formulate cat urine and feces odor remediation approaches to reduce odor impacts.
ARTICLE | doi:10.20944/preprints201811.0009.v1
Subject: Life Sciences, Other Keywords: campylobacter jejuni; VOCs; GC-MS SPME; nanowire sensors; PCA
Online: 2 November 2018 (03:28:13 CET)
Campylobacter infection affects more than 200,000 people every year in Europe and in the last four years trend shows an increase of campylobacteriosis. Main vehicle for transmission of the bacterium is contaminated food like meat, milk, fruit and vegetables. In this study, the aim was to find characteristic VOCs of C. jejuni in order to detect its presence with an array of MOX gas sensors. Using a starting concentration of 103 CFU/mL, VOCs were analyzed using GC-MS with SPME technique at the initial time (T0) and after 20 hours (T20). It has been found that Campylobacter sample at T20 is characterized by a higher number of alcohol compounds that the one at T0 and this is due to sugar fermentation. Sensors results showed the ability of the system to follow bacteria curve growth from T0 to T20 using PCA. In particular, this results in a decrease of ΔR/R0 value over time. For this reason, MOX sensors are a promising technology for the development of a rapid and sensitive system for C. jejuni.
ARTICLE | doi:10.20944/preprints202107.0416.v1
Subject: Biology, Anatomy & Morphology Keywords: Epilepsy; VOCs; Attention seeking behaviours; Remote Odour Delivery Mechanism (RODM)
Online: 19 July 2021 (14:30:08 CEST)
Abstract Epilepsy is a disorder of the brain and a seriously debilitating condition, which has been associated with injury, social stigmatisation and in some cases, sudden unexpected and premature death. A sense of profound isolation is felt by many individuals with epilepsy, and this community has expressed an urgent desire for an early warning system to allow them time to prepare for seizure onset. Surveys of dog owners with epilepsy have previously reported that some dogs can predict the onset of a seizure. The current study used an experimental design to investigate the alleged propensity of untrained pet dogs to react to human epileptic seizures. We hypothesised that seizures are associated with specific volatile organic compounds resulting in detectable odours which are the biomarker that triggers these reported behavioural changes in the dogs. Here we provide details of the first empirical test to demonstrate that pet dogs display several significant behavioural changes when they are exposed to seizure-related odours that apparently emanate from their owners. Using a repeated measures design experiment, recordings were made of the reactions of 19 untrained pet dogs to odours from sweat samples provided by three people with epilepsy and by two people without epilepsy (controls). The seizure-associated sweat samples were captured pre-seizure, during seizure and post-seizure. All samples were randomly delivered to individual dogs in a test area, using two bespoke pieces of apparatus called Remote Odour Delivery Mechanisms (RODM). One RODM delivered only experimental odours, the other delivered only control odours. Behavioural changes by the dogs on encountering the odour samples were recorded by video for later analysis. Consistent with our hypothesis, seizure-associated odours evoked significant behavioural changes in the dogs which were affiliative in nature and directed at their owners.
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/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/preprints201809.0568.v1
Subject: Chemistry, Organic Chemistry Keywords: essential oils; VOCs; GC-MS SPME; electronic nose; nanowire gas sensors; ANOVA.
Online: 28 September 2018 (13:22:44 CEST)
Essential oils are mixtures of compounds obtained from plants, including flowers, roots, bark, leaves, seeds,peel, fruits, wood, that have risen up in the last decades thanks to their beneficial properties as antibacterial, antifungal and anti-inflammatory agents. The aim of this study was to characterize and analyze 13 different commercial essential oils with two different techniques. The first is GC-MS, coupled with SPME, thanks to which 204 different VOCs have been identified. The results show that a total of 95 compounds was found only in one oil, while the others were found with different frequencies in many of them. The most represented class is that of terpenes, as widely reported in literature. The second technique is based on an array of chemical gas sensors. This system was used to investigate whether sensors are able to identify these products. It turned out that basil, cinnamon and carnation are the most identifiable oils with different number and typology of sensors, especially tin oxide and copper oxide nanowires, while cayeput and thyme are more mistakable samples. Thanks to this detailed study, it has been possible to reach and obtain novel insights for the future development of this type of research.
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.