LC-MS and GC-MS Analyses on Green Algae Penicillus capitatus: Cytotoxic, Antimicrobial and Anticholinesterase Activity Screening Enhanced by Molecular Docking & Dynamics and ADME Studies.

In this comprehensive screening study, the chemical composition, and cytotoxic, antimicrobial, and anticholinergic activities of the green algae Penicillus capitatus, collected from Antalya-Türkiye, were determined as in vitro and in silico. GC-MS analysis of the hexane extract revealed a high content of fatty acids, with hexadecanoic acid constituting half of the total fatty acid content. LC-HRMS analysis of the DCM:MeOH extract identified ascorbic acid as the most abundant compound, followed by (-)-epigallocatechin and salicylic acid. The DCM:MeOH extract exhibited potent cytotoxicity against MDA-MB-231 and MCF7 breast cancer cell lines, outperforming doxorubicin with lower IC50 values and a higher selectivity index. Additionally, the extract demonstrated significant antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans, along with selective inhibition of acetylcholinesterase (hAChE) over butyrylcholinesterase (hBChE). Molecular docking and dynamics studies revealed that apigenin-7-O-glucoside and epigallocatechin form stable interactions with estrogen receptor alpha (ERα) and hAChE, suggesting their potential as inhibitors. In silico ADME studies indicated favorable pharmacokinetic profiles for the detected compounds, supporting their potential as drug candidates. The promising cytotoxic activity of the P. capitatus extracts, coupled with significant antimicrobial properties and selective hAChE inhibition, highlights their therapeutic potential for breast cancer treatment, infection management, and neurodegenerative disease intervention.

Innovative disposable pipette extraction for concurrent analysis of fourteen psychoactive substances in drug users' sweat.

Widespread consumption of drugs of abuse worldwide has caused concern: it adversely affects public health, individual safety, and social structures. Experts are particularly alarmed because new psychoactive substances have been increasingly detected in biological samples. In recent years, several studies have focused on developing methods to identify psychoactive substances in alternative biological matrices, such as sweat. This approach holds promise for monitoring substance use, especially in individuals undergoing rehabilitation. Among the commonly employed analytical procedures, extraction using disposable DPX tips stands out as a novel, miniaturized, and promising technique. This study aimed to validate and to apply a method to analyze various substances, including amphetamine, methamphetamine, MDMA, MDA, MDEA, cocaine, cocaethylene, anhydroecgonine methyl ester, dibutylone, N-ethylpentylone, 25E-NBOMe, 25CNBOMe, 2CC, 2C-E, fentanyl, and carfentanil, in sweat samples simultaneously. In this method, sweat is collected by using laboratory-developed patches, and extraction is conducted with DPX-SCX tips. Gas chromatography coupled to mass spectrometry is employed to separate, to identify, and to quantify the analytes. Validation results indicated that the quantification limit ranged from 2 to 30 ng of analyte/patch, and that the method was linear for analyte concentrations ranging from 2 to 1100 ng/patch. The validated method was applied to analyze 30 sweat samples collected from volunteers drug users and processed by using both the selected ion mode (SIM) and full scan. The method was able to detect and to quantify substances such as cocaine, cocaethylene, anhydroecgonine methyl ester, MDMA, MDA, nicotine, cotinine, caffeine, procaine, lidocaine, and ethylamphetamine simultaneously. The recovery rates ranged from 72.4 % to 97.1 %. The analytes were stable in the biological matrix. In conclusion, the validated method proved effective and allowed the target analytes to be quantified in sweat samples, highlighting that sweat is a viable matrix for analyzing drugs of abuse.

Enzymatic synthesis of pyridine heterocyclic compounds and their thermal stability.

An efficient method was discovered for catalyzing the esterification under air using Novozym 435 to obtain pyridine esters. The following conditions were found to be optimal: 60 mg of Novozyme 435, 5.0 mL of n-hexane, a molar ratio of 2:1 for nicotinic acids (0.4 mmol) to alcohols (0.2 mmol), 0.25 g of molecular sieve 3A, a revolution speed of 150 rpm, a reaction temperature of 50 °C, and reaction time of 48 h. Under nine cycles of Novozym 435, the 80 % yield was consistently obtained. Optimum conditions were used to synthesize 23 pyridine esters, including five novel compounds. Among them, gas chromatography-mass spectrometry-olfactometry (GC-MS-O) showed phenethyl nicotinate (3g), (E)-hex-4-en-1-yl nicotinate (3m), and octyl nicotinate (3n) possessed strong aromas. Thermogravimetric analysis (TG) revealed that the compounds 3g, 3m and 3n exhibited stability at the specified temperature. This finding provides theoretical support for adding pyridine esters fragrance to high-temperature processed food.

Characterization of volatile profile from different coriander (Coriandrum sativum L.) varieties via HS-SPME/GC-MS combined with E-nose analyzed by chemometrics.

Headspace-solid phase microextraction/gas chromatography-mass spectrometry (HS-SPME/GC-MS) and electronic nose (E-nose) technologies were implemented to characterize the volatile profile of aerial part from 40 coriander varieties. A total of 207 volatile compounds were identified and quantified, including aldehydes, alcohols, terpenes, hydrocarbons, esters, ketones, acids, furans, phenols and others. E-nose results showed that W5S and W2W were representative sensors responding to coriander odor. Among all varieties, the number (21-30 species) and content (449.94-1050.55 µg/g) of aldehydes were the highest, and the most abundant analytes were (Z)-9-hexadecenal or (E)-2-tetratecenal, which accounted for approximately one-third of the total content. In addition, 37 components were determined the characteristic constituents with odor activity values (OAVs) ≥ 1, mainly presenting citrusy, fatty, soapy and floral smells. Hierarchical cluster analysis (HCA) and principal component analysis (PCA) could effectively distinguish different varieties. This study provided a crucial theoretical basis for flavor evaluation and quality improvement of coriander germplasm resources.

Chemical composition and antibacterial activity of essential oils from Daucus sahariensis Murb. roots and stems.

Daucus genus (Apiaceae) comprises economically relevant plants distributed in temperate regions. These plants are used mainly as food but are also known for their biological properties. Here, the essential oils (EOs) obtained by hydro-distillation of roots and stems of D.sahariensis Murb. growing in Algerian Sahara were studied by GC-MS analysis. Fifty-two and fifty-five compounds were identified from the roots and stems, representing 95.1% and 93.8% of the whole EOs respectively. The main constituents of the EO from roots were myristicin (29.2%), (E)-anethole (14.2%), cis-chrysanthenyl acetate (8%) and estragol (7.5%). In the EO from stems, the main constituents were α-pinene (18.6%), myrcene (16.7%), limonene (13.7%) and myristicin (8%). The antibacterial activity of EOs was evaluated by disc diffusion method and tested against Gram-positive and Gram-negative bacteria. Results showed a mild activity against Bacillus subtilis and Klebsiella pneumoniae for both EOs, which can be potentially used as antibacterial in phytotherapy.

Stability of selected exhaled breath volatiles stored in Tenax® TA adsorbent tubes at -80°C.

Preservation of the breath sample integrity during storage and transport is one of biggest challenges in off-line exhaled breath gas analysis. In this context, adsorbent tubes are frequently used as storage containers for use with analytical methods employing gas chromatography with mass spectrometric detection. The key objective of this short communication is to provide data on the recovery of selected breath volatiles from Tenax® TA adsorbent tubes that were stored at -80 C for up to 90 days. For this purpose, an Owlstone Medical's ReCIVA® Breath Sampler was used for exhaled breath collection. The following fifteen compounds, selected to cover a range of chemical properties, were monitored for their stability: isoprene, n-heptane, n-nonane, toluene, p-cymene, allyl methyl sulfide, 1-(methylthio)-propane, 1-(methylthio)-1-propene, -pinene, DL-limonene, ß-pinene, -terpinene, 2-pentanone, acetoin and 2,3 butanedione. All compounds but one (acetoin) were found to be stable during the first 4 weeks of storage (recovery within  2×RSD). Furthermore, n-nonane was stable during the whole of the investigated period.

Volatile Compounds for Discrimination between Beef, Pork, and Their Admixture Using Solid-Phase-Microextraction-Gas Chromatography-Mass Spectrometry (SPME-GC-MS) and Chemometrics Analysis.

This study addresses the prevalent issue of meat species authentication and adulteration through a chemometrics-based approach, crucial for upholding public health and ensuring a fair marketplace. Volatile compounds were extracted and analyzed using headspace-solid-phase-microextraction-gas chromatography-mass spectrometry. Adulterated meat samples were effectively identified through principal component analysis (PCA) and partial least square-discriminant analysis (PLS-DA). Through variable importance in projection scores and a Random Forest test, 11 key compounds, including nonanal, octanal, hexadecanal, benzaldehyde, 1-octanol, hexanoic acid, heptanoic acid, octanoic acid, and 2-acetylpyrrole for beef, and hexanal and 1-octen-3-ol for pork, were robustly identified as biomarkers. These compounds exhibited a discernible trend in adulterated samples based on adulteration ratios, evident in a heatmap. Notably, lipid degradation compounds strongly influenced meat discrimination. PCA and PLS-DA yielded significant sample separation, with the first two components capturing 80% and 72.1% of total variance, respectively. This technique could be a reliable method for detecting meat adulteration in cooked meat.

Coriandrum sativum L., essential oil as a promising source of bioactive compounds with GC/MS, antioxidant, antimicrobial activities: in vitro and in silico predictions.

Introduction: Coriandrum sativum L. essential oil (CS-EO) is being evaluated in vitro for its antioxidant and antimicrobial properties, and its volatile compounds are to be identified as part of this exploratory study. Methods: The processes underlying the in vitro biological properties were explained using in silico simulations, including drug-likeness prediction, molecular docking, and pharmacokinetics (absorption, distribution, metabolism, excretion, and toxicity-ADMET). Chemical screening of CS-EO was conducted using gas chromatography-mass spectrometry (GC-MS). Five in vitro complementary techniques were used to assess the antioxidant activity of CS-EO: reducing power (RP), 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonate) (ABTS) radical scavenging activity, ß-Carotene bleaching test (BCBT), and phosphomolybdenum assay (TAC). Results: According to GC-MS analysis, linalool (59.04%), γ-Terpinene (13.02%), and α-Pinene (6.83%) are the main constituents of CS-EO. Based on the in vitro antioxidant assay results, CS-EO has been found to have a superior antioxidant profile. Its estimated scavenging rates for ABTS+ are 0.51 ± 0.04 mg/mL, BCBT is 9.02 ± 0.01 mg/mL, and CS-EO is 1.52 ± 0.14 mg/mL. C. sativum demonstrated 6.13 ± 0.00 µg/mL for reducing power and 213.44 ± 0.45 mg AAE/mL for total antioxidant activity. The in vitro antimicrobial activity of CS-EO was assessed against five strains, including two gram-positive bacteria, two gram-negative bacteria, and one fungal strain (Candida albicans). Significant antibacterial and antifungal activities against all strains were found using the disc-diffusion assay, with zones of inhibition larger than 15 mm. The microdilution test highlighted the lowest MIC and MBC values with gram-positive bacteria, ranging from 0.0612 to 0.125% v/v for MIC and 0.125% v/v for MBC. The fungal strain's MFC was 1.0% v/v and its MIC was measured at 0.5%. Based on the MBC/MIC and MFC/MIC ratios, CS-EO exhibits bactericidal and fungicidal activity. The ADMET study indicates that the primary CS-EO compounds are good candidates for the development of pharmaceutical drugs due to their favorable pharmacokinetic properties. Conclusion: These results point to a potential application of this plant as a natural remedy and offer empirical backing for its traditional uses. It is a promising environmentally friendly preservative that can be used extensively in the food and agricultural industries to prevent aflatoxin contamination and fungal growth in stored goods.

GC/MS evaluation of the composition of the Aloe vera gel and extract.

This study aimed to investigate the potential use of Aloe vera (AV) as a food additive given its critical importance in food safety and health. Specifically, the natural antimicrobial and antioxidant properties of AV were examined to prevent food spoilage and extend its shelf life. This study was conducted using commercially available aloe vera gel (AVG) and aloe vera extract (AVE). These samples were tested using gas chromatography-mass spectrometry (GC-MS). The analysis involves identifying and quantifying the components using natural helium gas. The antimicrobial and antifungal effects of these components were evaluated and compared with those reported in the literature. GC-MS analysis revealed that the Aloe vera gel and extract contained various volatile components, including phenolic compounds, anthraquinone glycosides, and different esters. According to GC-MS results of the two different forms of AV, the main volatile compounds of the gel form were levoglucosan, tridecanoic acid, decanoic acid methyl ester, octadecanoic acid methyl ester, octadecanoic acid, nonadeca-1.18-diyn-4.16-diol and squalene, whereas the extract form contained volatile compounds with antifungal activity such as tridecanoic acid, octadecanoic acid methyl ester, octadecanoic acid, nonanoic acid and eicosyl acetate. Both samples exhibited antimicrobial and antifungal activities, especially against pathogens such as Staphylococcus aureus, Candida albicans, Aspergillus niger, and Escherichia coli. This study demonstrated the potential of Aloe vera gel and extract as a natural preservative for use in food because of its constituent components. This study highlights the potential use of Aloe vera as a natural additive in the food industry. Due to its antimicrobial and antifungal properties, Aloe vera offers an organic alternative to chemical additives. Aloe vera is effective at preventing food spoilage and extending shelf life, making it a suitable option for meeting consumer demand for organic and natural products.

Resistance of Nile tilapia fed with Padina boergesenii extract to Pseudomonas putida infection.

The aim of this research was to estimate the immunopotentiation effect of brown algae Padina boergesenii water extract on Nile tilapia, Oreochromis niloticus through resistance to Pseudomonas putida infection. Gas Chromatography Mass Spectrometry was utilized to characterize the seaweed phytoconstituents. One hundred and twenty-six fish were divided in triplicates into two equal groups corresponding to two diet variants that used to feed Nile tilapia for 20 successive days: a basal (control), and P. boergesenii water extract supplemented group. Fish samples were collected at 10-days intervals throughout the experiment. Serum biochemical constituents, total antioxidant capacity (TAC), and some immune related genes expression of the spleen and intestinal tissues of experimental fish were studied, as well as histological examination of fish immune tissues. Moreover, following 20 days of feeding, the susceptibility of Nile tilapia to P. putida infection was evaluated to assess the protective effect of the used extract. The findings indicated that the studied parameters were significantly increased, and the best immune response profiles were observed in fish fed P. boergesenii water extract for 20 successive days. A bacterial challenge experiment using P. putida resulted in higher survival within the supplemented fish group than the control. Thus, the lowered post-challenge mortality of the fish may be related to the protection provided by the stimulation of the innate immune system, reduced oxidative stress by higher activity of TAC, and elevated levels of expression of iterleukin-1beta (IL-1ß), beta-defensin (ß-defensin), and natural killer-lysin (NKl). Moreover, the constituents of the extract used showed potential protective activity for histological features of the supplemented fish group when compared to the control. Collectively, this study presents a great insight on the protective role of P. boergesenii water extract as an additive in Nile tilapia feed which suggests its potential for improving the immune response against P. putida infection.

Development and application of a novel extraction protocol for the monitoring of microplastic contamination in widely consumed ruminant feeds.

Plastics and, in particular, microplastics (MPs) (< 5 mm) are emerging environmental pollutants responsible for interconnected risks to environmental, human, and animal health. The livestock sector is highly affected by these contaminants, with 50-60 % of the foreign bodies found in slaughtered domestic cattle being recognized as plastic-based materials. Additionally, microplastics were recently detected inside ruminant bodies and in their feces. MPs presence in ruminants could be explained by the intensive usage of plastic materials on farms, in particular to store feeds (i.e. to cover horizontal silos and to wrap hay bales). Although feed could be one of the main sources of plastics, especially of microplastics, a specific protocol to detect them in ruminant feeds is not actually present. Hence, the aim of this study was to optimize a specific protocol for the extraction, quantification, and identification of five microplastic polymers (high-density polyethylene, low-density polyethylene, polyamide fibers/particles, polyethylene terephthalate and polystyrene) from feeds typically used in ruminant diets (corn silage, hay, high protein feedstuff and total mixed ration). Several combinations of Fenton reactions and KOH digestion were tested. The final extraction protocol involved a KOH digestion (60 °C for 24 h), followed by two/three cycles of Fenton reactions. The extraction recoveries were of 100 % for high-density, low-density polyethylene, polyamide particles, and polystyrene and higher than 85 % for polyethylene terephthalate and polyamide fibers. Finally, the optimized protocol was successfully applied in the extraction of microplastics from real feed samples. All the feeds contained microplastics, particularly polyethylene, thus confirming the exposure of ruminants to MPs.

Evaluation and optimisation of phenolic compounds extracted by supercritical carbon dioxide from the seeds of Plantago ovata and their comparison with conventional extraction.

This study's main objectives are to evaluate and confirm the effects of the extraction process, operating conditions, solvent type and solvent polarity on the yield and quality of the extracts. Supercritical carbon dioxide (scCO2) and Soxhlet were specially used in this study to extract bioactive chemicals from the seeds of a natural plant known as Plantago ovata. No studies have been published so far regarding the extraction from the seeds of this plant using scCO2.The effects of three operating parameters (pressure, temperature and particle size) on the extraction yield, total phenolic content, total flavonoid content (TFC), total tannin content (TTC) and antioxidant activity were assessed in this study using the Box-Behnken statistical experimental design (BBD). The chemical components in the extracts were separated and identified using gas chromatography mass spectrometry. According to the antioxidant activity results, scCO2 failed to produce bioactive compounds with interesting properties when operated within operating range conditions.

Discovering the volatilome fingerprint of selected traditional Cuban wines elaborated with native grapes, tropical fruits, and rice using DHS-TD-GC-MS.

Cuban wine is a traditional alcoholic beverage elaborated with a wide variety of raw materials, such as native grapes, tropical fruits, and rice, and different winemaking processes. Research on Cuban wines is almost nonexistent, and therefore, a study of these wines is necessary to improve their quality. Dynamic headspace (DHS)-TD-gas chromatography-mass spectrometry (GC-MS) analysis was carried out to establish the different aroma fingerprints of different Cuban wines. A total of 42 volatile aroma metabolites (VAMs) were identified, including esters, alcohols, aldehydes, acids, volatile phenols, terpenes, and lactones. The odorant activity values (OAV) of each VAM were obtained, and the esters were the most relevant group due to their highest OAV. Ethyl octanoate, hexanoate, and butanoate stand out and are considered key odorants in the aromatic fingerprint. The VAMs were grouped into seven aromatic series. Fruity series showed the highest OAVs due to the contribution of ethyl esters and acetates. Principal component analysis was used to identify the specific parameters most accurately reflecting the differences between the wines. Showing that fruity, spicy, and chemical aromatic series allow distinguishing the wines into three aroma types. These results may provide useful information for the selection of raw materials and optimization of the traditional winemaking processes of Cuban wines. PRACTICAL APPLICATION: This research contributes to knowledge of the aroma and the oenological parameters of traditional and selected Cuban wines (rice wine, tropical fruit wine, and native grape varieties). The establishing of the aroma fingerprint of these wines provides useful information for the industrial development of a quality product that may then be promoted in other areas of the world.

Study on Pharmacological Activities and Mechanisms of the Essential Oil of the Flowers of Hemerocallis citrina Baroni (EOFHCB) in the Treatment of Anxiety Disorders by GC-MS, Network Pharmacology, and Molecular Docking.

BACKGROUND: Hemerocallis citrina Baroni (Huanghuacai), a plant of the genus Hemerocallis in the family Asphodelaceae, is widely planted in China. Based on our survey results, the chemical compounds in the essential oil of the flowers of Hemerocallis citrina Baroni (EOFHCB) and relevant pharmacological activities have never been studied systematically. OBJECTIVE: To preliminarily decipher the pharmacological activities and mechanisms of EOFHCB in the treatment of anxiety disorders by GC-MS, Network Pharmacology, and Molecular docking. METHODS: EOFHCB compositions were identified using GC-MS, and their targets were predicted using Swiss Target Prediction databases. The targets of anxiety disorders were obtained by GeneCards, DisGeNET, and OMIM databases. The STRING database was used to construct the protein-protein interaction networks, and the DAVID database was used to carry out GO enrichment and KEGG pathway enrichment analysis. The EOFHCB-components-targetspathways- anxiety disorders network was constructed by Cytoscape software (Version 3.10.0). Finally, the result was verified by molecular docking. RESULTS: 28 chemical components were identified by GC-MS, including 3-furanmethanol (28.43%), 2-methyl-1-butanol (27.13%), nerolidol (10.62%), and so on, which correspond to 241 potential targets. Several 2440 biological processes, 187 cellular compositions, and 311 molecular functions were enriched by GO enrichment analysis and 174 pathways by KEGG enrichment analysis. The key targets are PTGS 2, SRC, DRD 2, ESR 1, MAOB, and SLC6A4. The most important pathway is the neuroactive ligand-receptor interaction. CONCLUSION: EOFHCB exerts its therapeutic effects on anxiety disorders through multicomponents, multi-targets, and multi-pathways, which provided new ideas and methods for the in-depth research of aromatic Chinese medicine in the treatment of anxiety disorders.

GC-MS/MS Analysis and Wound Repair Potential of Urtica dioica Essential Oil: In silico Modeling and In vivo Study in Rats.

BACKGROUND: The study aimed to assess the antioxidant and wound healing properties of Urtica dioica essential oil (UDEO) through a comprehensive evaluation involving in silico, in vitro, and in vivo analyses. The phytochemistry of UDEO was also investigated to identify trace compounds crucial. METHODS: Various injection methods of the multimode inlet (MMI) in chromatography were investigated to attain lower instrumental detection limits. Subsequently, in silico studies were employed to delve deeper into the potential biological activities of the identified compounds. Standard antioxidative tests, encompassing ABTS•+ and TAC, were performed. In vivo tests centered on wound healing were implemented using rat models. The rats were randomly allocated to four groups: saline solution, vaseline vehicle, cytol centella, and 5% UDEO ointment. Wound healing progress was evaluated through a chromatic study. RESULTS: Gas chromatography combined with triple quadrupole mass spectrometry (GC-MS/MS) analysis revealed the presence of 97 thermolabile compounds in UDEO. Subsequent in silico studies unveiled the potential of identified compounds to inhibit COX-2, TNF-α, and IL-6, suggesting a possible enhancement of anti-inflammatory responses and healing processes. In vitro tests elucidated the notable antioxidant capacity of UDEO, a finding reinforced by wound healing data, revealing a substantial closure rate of 89% following the topical application of UDEO. Notably, fibrinogen and C-reactive protein (CRP) levels were significantly reduced, indicating minimized oxidative stress damage compared to control. Additionally, UDEO exhibited an increase in antioxidant enzyme activities compared to control. CONCLUSION: The study concludes that UDEO possesses significant antioxidant and wound-healing properties, supported by its rich phytochemical composition. The findings suggest its potential application in therapeutic interventions for oxidative stress and inflammatory conditions.

Host selection by thrips is affected by the floral volatile profile of sunflower.

Thrips, Frankliniella intonsa, is a highly polyphagous pest with a worldwide distribution. F. intonsa-infested sunflower seeds show marked visual damage. The study findings revealed that significantly more F. intonsa infested confection sunflower compared to oilseed sunflower, via olfactometer bioassay studies, we found that compared with the flower and pollen of oilseed sunflowers, those of confection sunflowers attract F. intonsa. Considering this discrepancy in the preference of F. intonsa on oilseed and confection sunflowers, the volatiles of the flower and pollens of two sunflowers were analysed by gas chromatography-mass spectroscopy. The behavioural responses of F. intonsa were assessed for these compounds using Y-tube bioassays. Geranyl bromide, a unique volatile component of oilseed sunflowers, induced an assertive approach-avoidance behaviour in F. intonsa, whereas the unique component ethyl isovalerate in confection sunflowers attracted F. intonsa. F. intonsa adults demonstrated significant attraction to the blends of confection sunflowers. Furthermore, field verification revealed that intercropping confection and oilseed sunflowers could effectively control F. intonsa. The study provided insights into the chemical cues used by F. intonsa in locating hosts. Therefore, oilseed sunflowers can be used as repellent plants to prevent F. intonsa invasion.

Metabolomic Approach to Identify the Potential Metabolites from Alpinia malaccensis for Treating SARS-CoV-2 Infection.

The advent of the new coronavirus, leading to the SARS-CoV-2 pandemic, has presented a substantial worldwide health hazard since its inception in the latter part of 2019. The severity of the current pandemic is exacerbated by the occurrence of re-infection or co-infection with SARS-CoV-2. Hence, comprehending the molecular process underlying the pathophysiology of sepsis and discerning possible molecular targets for therapeutic intervention holds significant importance. For the first time, 31 metabolites were tentatively identified by GC-MS analysis from Alpinia malaccensis. On the other hand, five phenolic compounds were identified and quantified from the plant in HPLC-DAD analysis, including (-) epicatechin, rutin hydrate, rosmarinic acid, quercetin, and kaempferol. Nine GC-MS and five HPLC-identified metabolites had shown interactions with 45 and 30 COVID-19-associated human proteins, respectively. Among the proteins, PARP1, FN1, PRKCA, EGFR, ALDH2, AKR1C3, AHR, and IKBKB have been found as potential therapeutic targets to mitigate SARS-CoV-2 infection. KEGG pathway analysis also showed a strong association of FN1, EGFR, and IKBKB genes with SARS-CoV-2 viral replication and cytokine overexpression due to viral infection. Protein-protein interaction (PPI) analysis also showed that TP53, MMP9, FN1, EGFR, and NOS2 proteins are highly related to the genes involved in COVID-19 comorbidity. These proteins showed interaction with the plant phytoconstituents as well. As the study offers a robust network-based procedure for identifying biomolecules relevant to COVID-19 disease, A. malaccensis could be a good source of effective therapeutic agents against COVID-19 and related viral diseases.

Thermal desorption - gas chromatography - mass spectrometry (TD-GC-MS) analysis of PFAS used in food contact materials.

Per- and polyfluoroalkyl substances (PFAS) are used in food contact materials (FCMs), e.g. as production aids in the fabrication of PTFE based coatings for kitchenware or as additives in paper and board. Growing concerns about the environment and health related to PFAS have led to an increasing interest in monitoring PFAS levels in FCMs as well as their migration into food. In this study, method development for the analysis of PFAS by thermal desorption - gas chromatography - mass spectrometry (TD-GC-MS) was done. In addition to fluorotelomer alcohols (FTOHs), which are the only PFAS commonly analysed by GC-MS, it was proven that perfluorocarboxylic acids (PFCAs) and per- and polyfluoroether carboxylic acids (PFECAs) as well as their thermolysis products, perfluoroethers (PFEs) and perfluoroalkenes, can be analysed by GC-MS without prior derivatization. Screening for PFCAs and FTOHs was possible by electron impact ionization (EI) using group specific SIM fragments. Confirmation of identity has been done by EI scans as well as chemical ionization (CI) SIM measurements. LODs (limits of detection) of PFCAs, FTOHs and PFECAs in the TD-GC-MS instrument were in the low pg range. Thermal degradation of PFCAs and PFECAs during TD-GC-MS measurement was investigated.

Evaluation of GC-MS for identification and characterization of pneumococcal serotype 24A, 24B, and 24F capsular polysaccharide.

Analysis of pneumococcal polysaccharides (PnPs) has been an arduous task, especially in similar serotypes. Pneumococci invades the host immune response by modulating capsule structure with small genetic changes making them indistinguishable from similar serotypes by conventional modes of analysis. The new serotype 24F causing invasive pneumococcal-resistant infection is an analytical challenge for its analysis as related serotypes 24A and 24B Ps share a common backbone. The difference in the branched chain which contains arabinitol and ribitol in 24F and 24B respectively are stereoisomers making their identification even more challenging. The composition analysis by GC-MS revealed distinct peaks for arabinitol in 24F and 24A Ps and ribitol in Pn 24B serotype polysaccharide. The mass spectral analysis confirmed their identification along with a heterologous cross-reactivity which confirmed anti-Pn-24F mAb reactive to Pn 24B than Pn 24A. The quantitative analysis of pneumococcal 24A, 24B and 24F using GC-MS showed sensitive analysis over the concentration range 3.125-200 µg/mL with regression coefficient >0.99 making ideal modality for the characterization, identification, and quantitation of pneumococcal 24A, 24B and 24F similar serotypes.

Metabolic profiling and enzyme inhibitory activity of the essential oil of citrus aurantium fruit peel.

BACKGROUND: Bitter orange (Citrus aurantium) is a fruiting shrub native to tropical and subtropical countries around the world and cultivated in many regions due to its nutraceutical value. The current study investigated the metabolic profiling and enzyme inhibitory activities of volatile constituents derived from the C. aurantium peel cultivated in Egypt by three different extraction methods. METHODS: The volatile chemical constituents of the peel of C. aurantium were isolated using three methods; steam distillation (SD), hydrodistillation (HD), and microwave-assisted hydrodistillation (MAHD), and then were investigated by GC-MS. The antioxidant potential was evaluated by different assays such as DPPH, ABTS, FRAP, CUPRAC, and phosphomolybdenum and metal chelating potential. Moreover, the effect of enzyme inhibition of the three essential oils was tested using BChE, AChE, tyrosinase, glucosidase, as well as amylase assays. RESULTS: A total of six compounds were detected by GC/MS analysis. The major constituent obtained by all three extraction methods was limonene (98.86% by SD, 98.68% by HD, and 99.23% by MAHD). Differences in the composition of the compounds of the three oils were observed. The hydrodistillation technique has yielded the highest number of compounds, notably two oxygenated monoterpenes: linalool (0.12%) and α-terpineol acetate (0.1%). CONCLUSION: In our study differences in the extraction methods of C. aurantium peel oils resulted in differences in the oils' chemical composition. Citrus essential oils and their components showed potential antioxidant, anticholinesterase, antimelanogenesis, and antidiabetic activities. The presence of linalool and α-terpineol acetate may explain the superior activity observed for the oil isolated by HD in both radical scavenging and AChE inhibition assays, as well as in the enzyme inhibition assays.