Beta-carotene is a fat-soluble antioxidant commonly found in foods such as fruits, vegetables, and palm oil. Despite various liquid chromatography methods are proposed to detect and measure the sera carotenoid level, a long retention time to elute this marker is needed. This study attempted to develop a rapid reverse phase method in eluding beta-carotene in human sera. The researchers managed to elute the antioxidant in 2.2 minutes by applying a combination of a C8 column, mobile phase comprising of acetonitrile mixed with methanol in 70:30 proportion, and an ultra-high performance liquid chromatography system. The outputs had a good calibration curve (R²=0.959) and low coefficient of variation (0.2%), suggesting this protocol is reliable. A column with a lower carbon chain such as C8 allows the beta-carotene molecule to flow through the column faster. Besides, selecting solvents with high elution strength coupled with an ultra-high performance liquid chromatography system which equipped with high pressure can force the beta-carotene through the column in a shorter duration compared to previous reported methods. Therefore, it is recommended to adopt this protocol in epidemiological studies where beta-carotene is screened as a dietary biomarker associated with disease of interest by using human sera in the population level.

Our concern was to obtain a biocomposite material with improved properties of the constituent materials (poly(lactic- co-glycolic acid) (PLGA) and zinc–boron (Zn–B) complex) in accordance with the novelties in the field of delivery systems for therapeutic agents which lately redefine the importance of biopolymer nanocomposites with PLGA (biodegradable composites). The advantages of such a biomaterial target the health system, being easy to obtain, through a cost-effective method. The water/oil/water double emulsion method also allows the adjustment of the synthesis parameters, to maximize the degree of Zn–B complex encapsulation. The morphological aspects of the samples (size, shape, porosity) were established by scanning electron microscopy (SEM). Particle size distribution (by volume and by number) was determined by direct light scattering (DLS). For all the synthesized materials, the observed morphology was typical for PLGA, spherical one. The particle size distribution showed that depending on the synthesis conditions, the particles can be obtained with diameters between 10–450 nm range and the value of the zeta potential (ZP) shows that the particles have electronegative surface charge, which offers a favorable perspective on the phenomena of aggregation, flocculation, dispersion. It was observed, applying the design of experiments (DoE), that the size of the particles increased with increasing amounts of PLGA and polyvinyl alcohol (PVA) in the formulation, while ZP increased with higher PLGA and smaller PVA. The encapsulation efficiency was determined by ultra-high performance liquid chromatography/mass spectrometry (UHPLC/MS).

This study aimed to extract bioactive compounds from apple (Malus domestica) peel waste using supercritical CO2 extraction. The bioactive fractions from apple peels from the three Italian cultivars were extracted applying a temperature of 60 °C and a pressure of 250 bar for 15 min. 20% ethanol was used as a co-solvent. The extraction process was carried out at a flow rate of 2 mL/min and their total polyphenol (TP), anthocyanin (TA), ascorbic acid (AA), and antioxidant activity contents (TAC) were measured. The extracts from the Stark cultivar had the highest levels of polyphenols, anthocyanins, and ascorbic acid, while the Royal Gala cultivar had the highest total antioxidant activity. Chromatographic analyses were also performed to characterize polyphenols. The extracts were then tested for their effect on the mitochondrial NADH-ubiquinone oxidoreductase (Complex I) activity on mitochondria isolated from human embryonic kidney cells (HEK239) cells, with the Stark extracts showing the most positive response in terms of NADH oxidation. These findings highlight the potential of apple peel waste as a source of functional phytocompounds and suggest the Stark cultivar extracts may have pharmacological applications. This study supports the circular bioeconomy by promoting the use of waste products as a valuable resource.

Consumption of milk contaminated with antibiotic residues above the maximum residue limit (MRL) causes direct toxicity to humans and the development of superbugs that leads to the failure of antibiotic therapy and threatens human life. Besides, long-duration exposure might alter the nature of gut microflora results in the enhancement of many diseases. Therefore, we examined 300 raw and processed packet milk samples using thin layer chromatography (TLC) and ultra high performance liquid chromatography (UHPLC) method against five veterinary antibiotics and assessed the risk for consumers in Chattogram, Bangladesh. Risk analysis was calculated by using hazard quotient on the basis of 165 ml per capita milk consumption. We found a total of 7% prevalence of antibiotic residues in raw milk samples which were higher (8%) in individual samples than the pooled samples (4%). However, we did not find any processed packet milk samples as positive. The mean concentration of oxytetracycline residue was detected 61.29 µg/l and amoxicillin was 124 µg/l in individual milk samples. Risk analysis showed the hazard quotient values of 0.0056 for oxytetracycline and 0.0017 for amoxicillin residue which was confirmed that, no significant health risk associated with the consumption of milk produced and marketed in the study area. Our study might fill the gap of knowledge to measure the safety status of milk regarding public health issues.

In this paper, the experimental protocol which we disclose is designed to identify the values for both the constant in the Kozeny/Carman model, which relates to the linear component of permeability, and the variable kinetic coefficient in the newly minted Q- modified Ergun model, which relates to the non-linear components of permeability, without involving any new theoretical development. Moreover, kinetic contributions to measured pressure gradient, which are not accounted for in some currently accepted empirical fluid flow equations, such as Poiseuille’s for flow in empty conduits and Kozeny/Carman for flow in packed conduits, but which nevertheless contribute to measured pressure drop and thus hamper the identification of the value of the constant relative to the laminar component, are captured and lumped together into a single variable kinetic parameter-the kinetic coefficient.

Soybean, maize and bean are crops of great economic importance, but in the last years suffered with infestations of the caterpillar Helicoverpa armigera, being the main problem the resistance of this pest to most pesticides. Avermectin emamectin benzoate was recently released to control this pest. Other avermectins, like abamectin, doramectin, eprinomectin and ivermectin are used in large scale because they potent acaricidal, anthelmintic, and insecticidal activities. Thus, a simple and fast method for the determination of avermectins in these crops based on a quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction procedure and ultra-high performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS) analysis was developed and validated. For extraction, water followed by acetonitrile:isopropanol and a partition step with salts was stablished. With the clean-up step using activated EMR-Lipid, limits of detection of 1.2 μg kg-1 for abamectin, doramectin, emamectin benzoate and ivermectin, and of 2.4 μg kg-1 for eprinomectin were achieved. Accuracy and precision evaluated at low levels presented satisfactory results. The method was successfully applied in commercial samples and is a good alternative for routine analysis.

The present study was designed to investigate the bioactive compound in Rumextunetanus extracts (polygonaceae), a plant growing in GarâaSejnane region (NW-Tunisia). Hydro-methanol extracts of flowers and stems of Rumextunetanus were analyzed by RP-UHPLC-ESI-QTOF-MS in the negative mode to identify the maximum of bioactive compounds. Applied the aforementioned method, a total of 60 bioactive compounds were characterized for the first time in Rumextunetanus between them, 18 photochemical were firstly identified in the Polygonaceae family in negative ionization mode. Quantification of the identified compounds revealed that quercetin-3-O-glucuronide and (-)-epicatechingallate were the most abundant phenolic compounds in flowers and stems, respectively. Moreover, positive correlations were found between the antioxidant activity measured by DPPH and FRAP assays with the total phenolic compounds (r = 0.98; r = 0.99, respectively) and the abundance of some phenolic subfamilies such as hydroxycinnamic acids, hydroxybenzoic acids, flavonols and flavones with r > 0.86. The compounds displaying significant (P < 0.01) and good correlations with the antioxidant activity (r > 0.93) were hydroxybenzoic acid, rutin, quercetin-3-O-glucuronide, quercetin-3-O-glucoside, quercetin and luteolin-7-O-rutinoside. In addition, the flowers and stems of Rumex tunetanus showed different bioactive compound profiles and significant antioxidant properties of extracts. These results highlight the potential of the RP-UHPLC-ESI-QTOF-MS and MS/MS system to identify untargeted metabolic profiling of Rumex tunetanus. Overall, these results contribute to the clear explanation of the past and current usage of genus Rumex in folk medicine. Future investigations are necessary to develop purified antioxidant extracts, with the application of more selective extraction techniques.

The natural compounds of boron have many applications, including as dietary supplement. Communication is based on the discovery that diester chlorogenoborate complex can be detected and quantified from green coffee bean. The study reports that such diester molecule can also be synthesized in stable form by direct reaction of boric acid and chlorogenic acid, in a mixture of acetonitrile–water (1:1, v/v), left to evaporate over a period of 48 hours, at room temperature, resulting a spirocyclic form (diester complex). The diester complex, with its molecular structure and digestibility attributes has potential application as prebiotic in gut health, oral health and as micronutrient essential for microbiota to human and animals.

Abstract: Peptide pools composed of short amino acid sequences have proven to be versatile tools in various research areas and clinical applications. They are powerful tools for epitope mapping, immunotherapy, and vaccine development. Their importance lies in their ability to map complex protein structures, enabling a comprehensive understanding of immune responses and facilitating the identification of potential therapeutic agents. The application of peptide pools also extends to the field of personalized medicine, offering tailored solutions for diseases such as cancer and infectious diseases. Peptide pools are complex mixtures of immunostimulatory antigens primarily intended for T-cell stimulation. They are commercially available in many different compositions and variants. However, unlike other reagents that consist of only one or a few compounds, peptide pools are highly complex products with limited stability. This makes their quality control a major challenge. Quantitative peptide analysis usually requires sophisticated methods, in most cases isotope-labeled standards and reference materials. None of these are routinely available for these products. Synthesis and purification of all labeled peptides might be required. Usually, this approach would be prohibitively laborious and expensive. Therefore, an approach is needed to provide a practical and feasible method for quality control of peptide pools. With insufficient quality control, the use of such products could lead to incorrect experimental results, which would worsen the well-known reproducibility crisis in the biomedical sciences. Here we propose the use of ultra-high performance liquid chromatography (UHPLC) with two detectors, a standard UV detector (at 214 nm) for quantitative analysis and a high-resolution mass spectrometer (HRMS) for identity confirmation. To be cost-efficient and fast, quantification and identification are performed in one chromatographic run. An optimized protocol is shown, and different peak integration methods are compared and discussed. This work was performed using a peptide pool known as CEF, which consists of 32 peptides derived from cytomegalovirus (CMV), Epstein-Barr virus (EBV) and influenza virus, ranging from 8 to 12 amino acids in length.

The profile of secondary metabolites occurring in apple cuticular layer is not only characteristic for particular apple cultivar, but also dynamically reflects various external factors in growing environment. In this study, the possibility to authenticate apple samples based on analysis of their cuticular layer extracts was investigated. Ultra-high-performance liquid chromatography coupled to high resolution tandem mass spectrometry (UHPLC-HRMS/MS) was employed for obtaining metabolomic fingerprints. In total, 274 authentic apple samples, four cultivars harvested within the seasons 2020 to 2022 in the Czech Republic and Poland were analysed. The generated complex data processed by univariate and multivariate statistical methods enabled to build classification models for discrimination of apple cultivars as well as their geographical origin. The models showed very good performance in differentiation of Czech and Polish samples for three of four cultivars: ‘Gala’, ‘Golden Delicious’ and ‘Idared’, moreover, the validity of the models was verified over harvest seasons. The diagnostic markers, besides metabolites of triterpene biosynthetic pathway, mainly represented wax esters. ‘Jonagold’, which is known to be susceptible to mutations, was the only cultivar for which the unambiguous classification of geographical origin was not possible.