GC-MS Method For Analysis Research Articles

The major surface protein of malaria sporozoites is GPI-anchored to the plasma membrane

Glycosylphosphatidylinositol (GPI) anchor protein modification in Plasmodium species is well known and represents the principal form of glycosylation in these organisms. The structure and biosynthesis of GPI anchors of Plasmodium spp. has been primarily studied in the asexual blood stage of P. falciparum and is known to contain the typical conserved GPI structure of EtN-P-Man3GlcN-PI. Here, we have investigated the circumsporozoite protein (CSP) for the presence of a GPI-anchor. CSP is the major surface protein of Plasmodium sporozoites, the infective stage of the malaria parasite. While it is widely assumed that CSP is a GPI-anchored cell surface protein, compelling biochemical evidence for this supposition is absent. Here, we employed metabolic labeling and mass-spectrometry based approaches to confirm the presence of a GPI anchor in CSP. Biosynthetic radiolabeling of CSP with [3H]-palmitic acid and [3H]-ethanolamine, with the former being base-labile and therefore ester-linked, provided strong evidence for the presence of a GPI anchor on CSP, but these data alone were not definitive. To provide further evidence, immunoprecipitated CSP was analyzed for presence of myo-inositol (a characteristic component of GPI anchor) using strong acid hydrolysis and GC-MS for a highly sensitive and quantitative detection. The single ion monitoring (SIM) method for GC-MS analysis confirmed the presence of the myo-inositol component in CSP. Taken together, these data provide confidence that the long-assumed presence of a GPI anchor on this important parasite protein is correct.

Nematicidal glycosylated resorcylic acid lactones from the fungus Pochonia chlamydosporia PC-170 and their key biosynthetic genes.

Chemical study of the nematicidal biocontrol fungus Pochonia chlamydosporia PC-170 led to discovery of six resorcylic acid lactones (RALs), including three nematicidal glycosylated RALs, monocillin VI glycoside (1), colletogloeolactone A (2) and monocillin II glycoside (3), and three antibacterial non-glycosylated RALs, monocillin VI (4), monocillin IV (5) and monocillin II (6). The planar structure of the new compound monocillin VI glycoside (1) was elucidated using HRESIMS and NMR data, and its monosaccharide configuration was further determined through sugar hydrolysis experiment and GC-MS analysis method. Furthermore, their two biosynthetic-related PKS genes, pchE and pchI, were identified through the gene knockout experiment. The glycosylated RALs 1-3 exhibited nematicidal activity against Meloidogyne incognita, with LC50 values of 94, 152 and 64 μg/mL, respectively, and thus had great potential in the development of new nematicidal natural products to control M. incognita in the future.

Phytochemical Analysis and Antioxidant Potential of Ethanol Extracts of Anogeissus leiocarpus ( DC.) Guill &Perr and Acacia nilotica (L.) Delile

Acacia nilotica (Gum Arabic) and Anogeissus leiocarpus (African birch) are multipurpose plants that have being in used in African traditional system of medicine. Various studies have proved their antibacterial, anti-diabetic, anti-diarrheal and wound healing effects. The aim of this research was to investigate the phytochemical constituents and antioxidant potential of the ethanol extracts of Anogeissus leiocarpus stem bark and Acacia nilotica pod. Phytochemical screening was carried out using the standard protocol and compounds were identified by GC-MS and FT-IR analysis methods on spectrophotometer system. Antioxidant assay was carried out using the free radical scavenging of the 1-1-diphynyl-2-picrylhydrazyl radical (DPPH).The phytochemical screening revealed the presence of saponins, tannins, phenols, alkaloids, flavanoids and terpenoids in both the investigated plants extract. Result from GC-MS analysis identified 69 and 76 compounds in A.nilotica and A. leiocarpus respectively.

Green synthesis, spectroscopic investigation, quantum chemical and molecular docking studies of 3-methylisoxazolo [4,5-b]pyridine

The present work, synthesized molecular compound of MIP from carbinol extract of Hybanthus Enneaspermus by green synthesis method. The GC–MS analysis method has validated the molecular structure of MIP and revealed structural characteristics. FT-IR and UV-Visible spectra have been used to characterize the newly synthesized molecular molecule. DFT calculations employing the B3LYP/6-311++G(d,p) basis set are used to analyses the optimized molecular geometry and vibrational frequencies of the MIP compound. The Homo-Lumo energy gap of the MIP molecules is 5.4793 eV. The interaction (intra-inter, hydrogen bonding, and charge delocalization) of MIP molecules computed by NBO 3.1 program. TD-DFT was used to describe the electronic transition of ground state to excited state and compare with the recorded UV- Visible absorption spectra of MIP compounds. Molecular docking studies was interpreted and recorded the newly synthesis compound against 2YJR and IUSN receptor (lungs and kidney cancer).

Heliotropium bacciferum essential oil extraction: Compositions determination by GC-MS and anti-inflammatory and antibacterial activities evaluation

Heliotropium bacciferum plant is very important and has been used for medicinal values since ancient times. The present study deals with the extraction of essential oil (0.14 w/w) of this plant and its GC-MS analysis, anti-inflammatory, and anti-bacterial activities evaluation. GC analysis of essential oil confirmed 76 compounds with 49 terpenes and oxygenated hydrocarbons. The main components of this essential oil are agarospirol (15.15 %), rosifoliol (9.41 %), elemol (8.96 %), tau.-cadinol (8.05 %), linalool (5.37 %), shyobunol (5.36 %) cyclohexylmethyl tridecyl ester of oxalic acid (4.74 %), respectively. The essential oil showed quite good anti-inflammatory activity while this oil indicated excellent anti-bacterial activity against 3 g-positive pathogenic bacteria (Bacillus subtilusATCC 6633, Entrococcus faecalis ATCC 29212, and Bacillus cereusATCC 11778). The essential oil of Heliotropium bacciferum showed great potential as an anti-inflammatory and anti-bacterial agent. Therefore, the reported extraction and GC-MS analysis methods are useful to extract the essential oil and determine the composition of other plants. The extracted essential oil may be used to treat several diseases.

Simultaneous determination of twelve natural estrogens in dairy milk using liquid-liquid extraction and solid-phase extraction coupled with gas chromatography-mass spectrometry.

There have been many analytical methods for natural estrogens in commercial dairy milk samples, but in most of which, only four major estrogens (estrone (E1), 17β-estradiol (E2), estriol (E3), and 17α-estradiol (αE2)) were included. This work developed an effective GC-MS analytical method for simultaneous analysis of twelve natural estrogens in commercial dairy milk sample, in which eight far-less well-known natural estrogens (2-hydroxyestone (2OHE1), 4-hydroxyestrone (4OHE1), 2-hydroxyestradiol (2OHE2), 4-hydroxyestradiol (4OHE2), 16-epiestriol (16epiE3), 16α-hydroxyestrone (16αOHE1), 16-ketoestradiol (16ketoE2) and 17epiestriol (17epiE3)) were included besides the four major natural estrogens. With liquid-liquid extraction and solid phase extraction, twelve natural estrogens in commercial dairy milk could be effectively extracted. The established method showed good linearity (R2 > 0.9991), low limits of detections (LODs, 0.02-0.11 ng/g), as well as excellent recoveries (64-117%) with satisfactory low relative standard deviations (RSDs, 0.8-14.7%). This established method was applied to seven commercial dairy milk samples, and all the twelve natural estrogens were frequently detected except for 4OHE2 without detection in any sample. Our results showed that the concentration contribution ratios of the eight far-less well-known natural estrogens in commercial dairy milk samples contributed to 32-83%, while the corresponding contribution ratios based on estrogen equivalence (EEQ) were 21-62%. This work highlighted the high abundance of the eight far-less well-known natural estrogens in commercial dairy milk based on both concentration and EEQ, which has been neglected for a long time.

Phytochemical analysis and antifungal activity of Azadirachta indica and Balanites aegyptiaca seed extracts against Fusarium oxysporum isolate on tomatoes

Fusarium oxysporum is the causative agent of tomato wilt and is an important disease of tomato crops worldwide. Management through chemical fungicides causes serious environmental damage and human health. This study assesses the antifungal potential of biochemical compounds of Azadirachta indica and Balanites aegyptiaca seeds extracts identified by GC-MS analytical method against F. oxysporum. Acetone, methanol and aqueous extracts of A. indica and B. aegyptiaca at 15, 30 and 60 μL/mL concentrations and synthetic fungicide (3.33 g/L) were tested in vitro in triplicate. Mycelial growth and Minimum inhibitory concentrations (MIC50, MIC90) were evaluated 8 days after inoculation (DAI). As results, 55 and 34 phytochemical compounds were identified in seed extracts of A. indica and B. aegyptiaca respectively. Methanol extract of A. indica and B. aegyptiaca at 60 μL/mL concentration showed a total inhibition (100%) of F. oxysporum mycelial growth. Low MIC50 values were obtained with aqueous extract of A. indica (8.77 μL/mL) and methanol extract of B. aegyptiaca (17.91 μL/mL). The tentative action mode showed that the methanol extract of both plants induced wall lysis of F. oxysporum. These results suggest that A. indica and B. aegyptiaca seed extracts have potent antifungal activity and could be used as an alternative to control F. oxysporum. Keywords: Neem, desert date, bioactive compounds, mycelial growth, antifungal activity, Fusarium oxysporum

Pomelo (Citrus maxima. Merr) essential oil extraction by cold pressing and hydrodistillation methods and comparison of chemical composition

Essential oils extraction from the shell bring many applications in life, as well as contribute to the development of the food flavoring and cosmetic industry. Pomelo (Citrus maxima Merr) essential oil (EO) was extracted by cold pressing and hydrodistillation methods. The EO content obtained was 0.067% and 0.33%, respectively. The chemical composition was determined by the GC-MS analysis method, with 4 main components being D-Limonene, β-Myrcene, α-Pinene, and α-Phellandrene which exhibited high antibacterial and antioxidant capacity). The EO obtained from pomelo peels by cold pressing conditions was limited and less effective with more natural aroma, as compared to the hydrodistillation methods. Therefore, further research on EO pressing equipment and methods that can be used for effective oil extraction and recovery are necessary.

Asphaltite Pyrolysis in Fluidized Bed Reactor

In this study, the pyrolysis properties of asphaltite samples taken from Şırnak and Hakkari regions in a fluidized bed reactor under catalyst and non-catalyst conditions were determined by rapid and batch pyrolysis. Basic analysis, FTIR and XRF analyses were performed for the raw material. GC-MS analysis methods were used for liquid pyrolysis products and FTIR were used for solids. In order to acquire the condition of the highest liquid product yield in pyrolysis, several effective variables such as particle diameter, vacuum, nitrogen flow rate, temperature, raw material feed rate, catalyst type, raw material type and duration were experimented and the results were evaluated. In general, the vacuum effect has led to an increase in liquid product yield and a decrease in gas product yield. Liquid product yield increased at 700°C pyrolysis temperature in continuous feed system and 550 - 650°C in batch system. In the pyrolysis studies carried out, a maximum liquid product yield of 16.5% was achieved in the continuous fed reactor at 700°C temperature, 400 mmHg vacuum, 2 g/min feed rate and 500 µm particle size.

Emission and Mechanical Properties of Glass and Cellulose Fiber Reinforced Bio-Polyamide Composites.

Climate change, access, and monopolies to raw material sources as well as politically motivated trade barriers are among the factors responsible for a shortage of raw materials. In the plastics industry, resource conservation can be achieved by substituting commercially available petrochemical-based plastics with components made from renewable raw materials. Innovation potentials are often not used due to a lack of information on the use of bio-based materials, efficient processing methods, and product technologies or because the costs for new developments are too high. In this context, the use of renewable resources such as fiber-reinforced polymeric composites based on plants has become an important criterion for the development and production of components and products in all industrial sectors. Bio-based engineering thermoplastics with cellulose fibers can be used as substitutes because of their higher strength and heat resistance, but the processing of this composite is still challenging. In this study, composites were prepared and investigated using bio-based polyamide (PA) as a polymer matrix in combination with a cellulosic fiber and, for comparison purposes, a glass fiber. A co-rotating twin-screw extruder was used to produce the composites with different fiber contents. For the mechanical properties, tensile tests and charpy impact tests were performed. Compared to glass fiber, reinforced PA 6.10 and PA 10.10, a significantly higher elongation at break with regenerated cellulose fibers, can be achieved. PA 6.10 and PA 10.10 achieve significantly higher impact strengths with the regenerated cellulose fibers than the composites with glass fibers. In the future, bio-based products will also be used in indoor applications. For characterization, the VOC emission GC-MS analysis and odor evaluation methods were used. The VOC emissions (quantitative) were at a low level but the results of the odor tests of selected samples showed values mostly above the required limit values.

Fully Automated QuEChERS Extraction and Clean-up of Organophosphate Pesticides in Orange Juice

A fully automated QuEChERS extraction and extract clean-up method for GC-MS and LC-MS analysis is presented by using an industry standard robotic x,y,z-sampling system. The application describes the analysis of organophosphate pesticides from homogeneous liquid samples, as an example orange juice was used. The automated workflow includes the extraction with acetonitrile, salting out and using a µSPE cartridge for matrix clean-up prior to injection into a GC-MS/MS system. The method validation techniques such as pre-spike and post-spike were fully integrated into the automated workflow as well. Calibration linearities of the applied organophosphate pesticides in orange juice matrix range from 1 to 100 ng/mL with a precision achieved better than 0.995 for all compounds. By spiking 10 ng/mL of pesticides into the orange juice samples, recoveries were obtained in the of range 70% – 115%, while the precision from pre-spike (n=7) and post-spikes (n=6) under the same concentration was less than 10% RSD. The calculated method detection limits (MDLs) of the monitored pesticides were in the range of 1.8 ng/mL to 4.1 ng/mL which are well below the regulated maximum residue limits (MRLs) of 10 ng/g for these pesticides.

Analysis of Seeds and Rhizomes of Spices for Metals, Amino Acids, Polyphenols, Flavonoids, and Antioxidant Capacity for Evaluation of the Nutritional Quality

Eleven plant extracts from the seeds and rhizomes of spices cultivated in Transylvania were investigated. To evaluate seeds and rhizomes nutritional profiles, several parameters were analyzed including metals, amino acids, polyphenols, flavonoids, and antioxidant capacity. The antioxidant activity, polyphenols, and flavonoids were determined using UV-Vis analytical methods. From investigated seeds and rhizomes, the most pronounced antioxidant character and the highest concentration of polyphenols were achieved in nutmeg seeds, allspice seeds, and ginger rhizomes. The highest flavonoid content was identified in turmeric rhizome and dill seeds. For the free amino acids quantification, a GC-MS analytical method using the 15N-glycine as internal standard was used. 16 amino acids were determined in the analyzed samples, and ginger rhizome and oregano seeds proved to have the highest content of essential amino acids. The trace metals were detected using inductively coupled plasma – optical emission spectrometry (ICP-OES). Essential trace elements (Cr, Mn, Co, Ni, Cu, and Zn) and toxic trace elements (As, Cd, and Pb) were determined in the samples. From essential trace elements, Mn and Zn were quantified in higher concentrations; for toxic elements As and Cd were found in the studied herbs. The findings indicate that the studied herbs parts may be valuable sources of compounds with bioactive properties.

Biosynthesis of silver nanoparticles using Antidesma acidum leaf extract: Its application in textile organic dye degradation

A cost-efficient, non-toxic and sustainable route for synthesis of silver nanoparticles (AgNPs) from Antidesma acidum, a tropical plant of North-East India; was adapted with its application to textile organic dye degradation. The formation of AgNPs were confirmed by UV–visible spectroscopy, fourier transform infra-red spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM) and energy-dispersive spectroscopy (EDS). It was observed that, the bioreduced AgNPs were spherical in shape with particle size 10 nm. Now-a-days, the environmental friendly bio-synthesized nanoparticles and its application in the field of water pollution control is one of the most amazing field of research. Textile dyes like congo red, methylene blue, methyl orange etc., are highly carcinogenic and causes water pollution when released to waste water. Herein, high and fast catalytic degradation of textile dyes; methylene blue (MB) and congo red (CR) were observed with biosynthesized AgNPs. The degradation rate of MB (81%) < the degradation rate of CR (90%) at 18 min and 20 min respectively. Intermediates of textile dye degradation were also detected in the present work with GC–MS analytical method.

Hydrothermal liquefaction of biomass with molybdenum, aluminum, cobalt metal powder catalysts and evaluation of wastewater by fungus cultivation

In this study, the Ammi visnaga plant was liquefied in the presence of Mo, Al and Co metal powder catalysts and without catalyst. Liquefaction trials were carried out at 225, 250, 275 and 300 °C reaction temperatures and reaction times of 0, 15, 30 and 45 min. The highest liquid product yield was determined as 42.31% in the experiment without catalyst and 39.42% with Mo catalyst at 300 °C. GC-MS, XRD, TOC, SEM-EDX and Elemental analysis methods were used to characterization of solid and liquid product. The highest energy values were determined as 25.34 MJ/kg for light oil and 29.69 MJ/kg for heavy oil with Co catalyst. In order to investigate the agricultural application potential, the effects of the wastewater obtained at the end of the trials on Trichoderma harzianum, Clonostachys rose and Rhizoctonia solani fungi were investigated. It was determined the bioagent fungi developed and pathogen growth was inhibited.

Recommended and verified stability indicating GC–MS procedures for green separation of quaternary mixture of naphazoline, ephedrine, methylparaben, and naphazoline impurity

A GC–MS analytical method, for the estimation of a vasoconstrictive drug combination of naphazoline nitrate and ephedrine hydrochloride, for allergic rhinitis treatment, in the presence of a photo-absorptive anti-bacterial additive (methylparaben) and naphazoline impurity (1-naphthaleneacetic acid), is offered concerning the cutting-edge trend in drug analysis. Environment, cost, and time factors are considered mainly in the establishment of the proposed method. The mixture is analyzed on the highly polar GC stationary phase of (5 % Phenyl Methyl) Silox. The two ions of m/z 209 and 58 were nominated to estimate naphazoline nitrate and ephedrine hydrochloride, correspondingly. Reduction in sample size is achieved by preparing mixture solutions in different drug ratios for calibration curves construction, using ethanol as a typical green solvent referring to its non-toxicity and renewability. The novel and validated chromatographic method is established for the analysis of the two drugs, concurrently in pure form ensuing optimum linearity in the range of 5–30 ppm (r = 0. 99988) for naphazoline nitrate and 15–45 ppm (r = 0. 98865) for ephedrine hydrochloride. The retention times (Rt) of naphazoline nitrate and ephedrine hydrochloride, methylparaben, and 1-naphthaleneacetic acid are 8.7, 3.2, 3.9 & 6.9 min, respectively. Statistical analyses are performed for the validated method, proving the reliability and robustness of the results. The method is successfully applied to analyze the drugs in Deltarhino nasal solution. The method is highly recommended in the quality assurance assessment of the drugs’ raw materials and dosage form. The new GC–MS method is preferred over the old described HPLC one concerning greenness characteristics and reduction of sample size when scanning the greenness characteristics using AGREE and GAPI tools.

Characterization of the Extracellular Volatile Metabolome of Pseudomonas Aeruginosa Applying an in vitro Biofilm Model under Cystic Fibrosis-Like Conditions.

Cystic fibrosis (CF) is an autosomal recessive hereditary disease that leads to the production of thickened mucus in the lungs, favouring polymicrobial infections, such as chronic lung infections with the bacterial opportunistic pathogen Pseudomonas aeruginosa. A biofilm model in combination with an adapted sampling and GC-MS analysis method were applied to in vitro studies on different variables influencing the composition of the extracellular volatile metabolome of P. aeruginosa. A significant influence on the metabolome could be demonstrated for the culture medium as well as the atmosphere during cultivation (aerobic or anaerobic). Furthermore, a significant influence of the mucoid (alginate-overproducing) phenotype of the bacterium on quantity and composition of volatile organic compounds could be observed. Based on the results a solid culture medium was developed to simulate the nutrient conditions in the lungs of a CF patient. The extracellular volatile metabolome of bacterial strains P. aeruginosa ATCC 10145, PAO1 and FRD1 was characterized under CF-like conditions. Bacterial strain-dependent metabolites were identified. When P. aeruginosa PAO1 and FRD1 clinical isolates were compared, 36 metabolites showed significant variations in intensities. When the clinical isolates were compared with the reference strain (P. aeruginosa ATCC 10145), 28 metabolites (P. aeruginosa PAO1) and 70 metabolites (P. aeruginosa FRD1) were determined whose peaks showed significant deviation (p > 95%) in intensity. Furthermore, the bacterial strains could be differentiated from each other by means of two principal components.

Contamination of Water, Sediment and Fish with Residues of Pesticides Used in Cotton Production in Northern Benin.

In Northern Benin, insecticides are used for cotton production. These insecticides can be easily transferred to water ponds close to cotton fields. To monitor insecticides levels in water, sediments and fish samples from water ponds, a GC-MS analytical method was developed to detect residues of endosulfan, DDT and its parent compounds, isomers of HCH, pyrethroids and chlorpyrifos. In addition, the influence of storage conditions of water sample on pesticides determination performance has been studied. The limits of quantification were between 0.16 and 0.32µg/L in water, 0.5 and 1μg/kg in sediment and 1 and 2μg/kg in fish. Twenty samples of water, twenty of sediments and forty of fish were taken in four different water reservoirs at five different times. Alpha-endosulfan, lambda-cyhalothrin and permethrin were identified in sediment while p,p'-DDE, α- and β-HCH, chlorpyrifos, lambda-cyhalothrin and permethrin were detected in fish. Only organochlorines were determined in water because of the lack of recovery of pyrethroids from water stored in glass. Concentrations of insecticide residues in sediment for all water ponds ranged from non-detected to 101µg/kg and from non-detected to 36µg/kg in fish. Preliminary risk assessment for consumers of the North of Benin showed that the Estimated Daily Intakes were lower than the Acceptable Daily Intakes and Acute Reference Doses for all consumers. However, as one fish can be contaminated by five pesticide residues at the same time, it is not possible to exclude a risk for the consumer due to his exposure to mixtures of pesticides.

Eco-Friendly Direct GC–MS Method for Estimation of Niacin and Related Impurities Involving Pyridine in Food Supplements

Niacin is a water-soluble vitamin whose deficiency causes many disorders and diseases, including pellagra and high blood cholesterol. Herein, niacin and four common impurities, isonicotinic acid (ISO), 5-ethyl-2-methylpyridine (MP), pyridine-2, 5-dicarboxylic acid (PDC) and pyridine PYR, are simultaneously analyzed, where PYR is known as potentially nephrotoxic and hepatotoxic. The separation of a mixture using gas chromatography–mass spectroscopy (GC–MS) without any derivatization steps was the main target. Many studies have been published to study Niacin and its impurities using colorimetry and HPLC. GC–MS was selected to study the analyzed mixture owing to its known sensitivity and selectivity. In this study, a single quadrupole mass spectrometer operated in selected ion monitoring (SIM) mode at an electron ionization energy of 70 eV was applied for the quantitative analysis of Niacin. Helium was used as the carrier gas and adjusted to run through an HP-5ms (5%-phenyl)-methylpolysiloxane column. Statistical analysis proved that this method is equally effective as the previously reported method. Importantly, this study was eco-friendly as compared to the reported high performance thin layer chromatographic method (HPTLC). Finally, this study provides a new and valid eco-friendly method analysis to determine the concentration of niacin and its common impurities at very low concentration. Conclusion: A simple, rapid accurate and green GC–MS analytical method was developed and validated to determine niacin and its related official impurities.

GC-MS analysis of phytoconstituents from Ruellia prostrata and Senna tora and identification of potential anti-viral activity against SARS-CoV-2

SARS-CoV-2 is an etiologic agent responsible for the coronavirus disease 2019 (COVID-19) pandemic. The virus has rapidly extended globally and taken millions of lives due to the unavailability of therapeutics candidates against the virus. Till now, no specific drug candidates have been developed that can prevent or treat infections caused by the pathogen. The main protease (Mpro) of the SARS-CoV-2 plays a pivotal role in mediating viral replication and mechanistically inhibition of the protein can hinder the replication and infection process of the virus. Therefore, the study aimed to identify the natural bioactive compounds against the virus that can block the activity of the Mpro and subsequently block viral infections. Initially, a total of 96 phytochemicals from Ruellia prostrata Poir. and Senna tora (L.) Roxb. plants were identified through the gas chromatography-mass spectrometry (GC-MS) analytical method. Subsequently, the compounds were screened through molecular docking, absorption, distribution, metabolism, excretion (ADME), toxicity (T), and molecular dynamics (MD) simulation approach. The molecular docking method initially identified four molecules having a PubChem CID: 70825, CID: 25247358, CID: 54685836 and, CID: 1983 with a binding affinity ranging between −6.067 to −6.53 kcal mol−1 to the active site of the target protein. All the selected compounds exhibit good pharmacokinetics and toxicity properties. Finally, the four compounds were further evaluated based on the MD simulation methods that confirmed the binding stability of the compounds to the targeted protein. The computational approaches identified the best four compounds CID: 70825, CID: 25247358, CID: 54685836 and, CID: 1983 that can be developed as a treatment option of SARS-CoV-2 disease-related complications. Although, experimental validation is suggested for further evaluation of the work.

Rapid adulteration detection of cold pressed oils with their refined versions by UV\u2013Vis spectroscopy

The aim of this study is the rapid detection of food pressed oils adulteration with their refined versions, using UV–Vis spectroscopy. The study investigates some common oil physico-chemical parameters such are: density, viscosity, refractive index, acid index, peroxide value, saponification index, to detect differences between cold pressed oils versus refined ones, for some food-grade oils found on Romanian market, as well as FT-IR spectroscopy and GC–MS analytical method, obtaining similar results to those presented in the literature data. The difference between some of the obtained results is not relevant for telling the cold-pressed oils from their refined version for adulteration investigation purpose. Colour analysis instead is a very good method to differentiate a cold pressed oil from a refined one. Taking this into account, the cold pressed oils and their refined versions were mixed in different proportions, and their colour properties were analyzed, obtaining linear dependences for a* and b* CIE L*a*b* parameters with cold pressed oil content in the mixture. Dependence equations were proposed.