Chromatography-electrospray Ionization-tandem Mass Research Articles

Efficient Simultaneous Isolation of Pinostrobin and Panduratin A from Boesenbergia rotunda Using Centrifugal Partition Chromatography.

The bioactive flavonoids pinostrobin (PN) and panduratin A (PA) from Boesenbergia rotunda are essential for research and therapeutic applications. This study introduces an innovative method utilizing ultrasound-assisted extraction with n-hexane pre-treatment, followed by one-step centrifugal partition chromatography (CPC) purification. Extraction efficiency was evaluated using ultra high-performance liquid chromatography (UHPLC), and the isolated compounds were characterized through 1H-NMR and liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS), adhering to AOAC validation guidelines. Optimal extraction conditions comprised a particle size of 125 μm, a solid-to-liquid ratio of 1:30 g/mL, and a 10 min extraction time, yielding a crude extract of 6.96 ± 0.07%. Using an n-hexane/MeOH/water (5/3.4/1.6, v/v) solvent system in ascending mode, PN (2.16 mg, 98.78% purity) and PA (0.4 mg, 99.69% purity) were isolated from 67 mg of crude extract within 30 min. This streamlined approach enhances purification efficiency, allowing for faster extraction and higher purity, making it a suitable method for commercial applications.

Direct aqueous injection LC−ESI-MS/MS analysis for the determination of 23 EU watch list substances in whole water samples

The Watch List (WL) monitoring program in the European Union (EU) aims to identify and prioritize emerging pollutants in the aquatic environment that may pose risks to human health and the environment. Thus, reliable methods are needed to determine these substances. This study presents the development of a simple, fast, and green method for analysing 23 WL substances (4 antibiotics, 9 azole compounds, 6 other pesticides, and 4 sunscreens), covering a range of medium to very low polarity (log Kow 2.2–6.9), in whole environmental water samples using direct aqueous injection (DAI) in combination with liquid chromatography–electrospray ionization tandem mass spectrometry (LC–ESI-MS/MS). To process the samples, 0.5 mL of acetonitrile is added to 1 mL of raw water, followed by brief shaking. The mixture is then centrifuged to remove sedimented suspended solids before being injected into the LC instrument. A rigorous analytical greenness metric for sample preparation (AGREEprep) assigned this procedure a green score of 0.61. The method showed satisfactory performance characteristics for all analytes under investigation, including limits of quantification meeting the WL requirements, recoveries in the range of 79–120%, and intra-day precision with relative standard deviations in the range of 1.9–20%. The method is suitable for screening and monitoring purposes, as confirmed by the analysis of real samples.

Insight into the Coextrusion Mechanism between Whey Protein Isolate and Cysteine.

The disulfide cross-linking sites of whey protein isolate (WPI) coextruded with dissolved cysteine (Cys) at concentrations of 0, 20, 40, 60, 80, and 100 mM were analyzed by liquid chromatography electrospray ionization tandem mass spectrometry (LC/MS/MS) combined with pLink software, and the structure and gel water distribution of WPI during coextrusion (≤50 °C) were also investigated. LC/MS/MS demonstrated that α-La (6) and α-La (120) were the most active sites for intermolecular disulfide cross-linking of α-La. Meanwhile, the molecular weight of protein polymers in coextruded WPI-Cys was the largest at 100 mM Cys, and α-lactalbumin was the main reactant for polymerization from the result of SDS-PAGE and size exclusion chromatography. Additionally, the high concentration of Cys caused the secondary structure of WPI to gradually change from a highly ordered to a disordered structure during coextrusion. In addition, with an increasing concentration of Cys, the free sulfhydryl group of proteins and the binding force to immobilized water gradually increased. Therefore, this work revealed the disulfide cross-linking mechanism between WPI and Cys under low-temperature coextrusion at the molecular level, and the obtained coextruded cross-linked WPI could serve as a novel food ingredient with excellent water-holding capacity for the food industry.

Dynamic Changes in Flavonoids’ Accumulation Pattern in Tilia miqueliana Flowers at Different Developmental Stages Based on Widely Targeted Metabolomic Analysis

Tilia miqueliana is an endemic species belonging to the genus Tilia L. (Tiliaceae) in China, which is known for its fragrant flowers and nectar, but the dynamic changes in metabolites during its growth and development are still unclear. In this study, the metabolic profiles from T. miqueliana flowers at three developmental stages were detected by performing an ultra-performance liquid chromatography–electrospray ionization–tandem mass spectrometry (UPLC-ESI-MS/MS)-based widely targeted metabolomic analysis. A total of 1138 metabolites were detected, with 288 Differentially Accumulated Metabolites (DAMs) determined, flavonoids accounting for the largest proportion. The trend analysis showed that DAMs present seven distinctive patterns, and subclass 5 obtained the largest amount with continuously increased relative content during flower development. The Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation and enrichment analysis of DAMs showed different overlap and variability in metabolic pathways, indicating different directions of flavonoids’ metabolic flux in the three developmental stages. A correlation network analysis further revealed five core metabolites that played essential roles in flavonoid biosynthesis. This research provides comprehensive insights into the exploitation and utilization of T. miqueliana as well as a scientific basis for phylogenetic studies of the genus Tilia.

(S)-2,5-dioxopyrrolidin-1-yl-1-(4,6-dimethoxy-1,3,5-triazin-2-yl)pyrrolidine-2-carboxylate derivatization combined with UPLC/ESI-MS/MS as a powerful method for dipeptide determination in foods: An application example in fermented cocoa beans

Dipeptides play a crucial role in food flavor, as well as in physiological and nutritional functions. However, as comprehensive methods for determining dipeptides are still under development, the dipeptide composition of foods remains largely unexplored. This study proposed a novel analytical method for dipeptides by applying an amino acid determination technique we previously developed: (S)-2,5-dioxopyrrolidin-1-yl-1-(4,6-dimethoxy-1,3,5-triazin-2-yl)pyrrolidine-2-carboxylate (DMT-(S)-Pro-OSu) derivatization coupled with ultra-performance liquid chromatography–electrospray ionization tandem mass spectrometry (UPLC/ESI-MS/MS). The DMT-(S)-Pro-OSu derivatization of dipeptides improved both separation in LC and detection sensitivity in MS, allowing for the optimized acquisition of m/z and elution times for 313 available dipeptides, and enabling the absolute quantification of 126 dipeptides in a simultaneous analysis. Subsequent analysis of fermented cocoa beans detected and quantified 42 dipeptides, revealing distinct dipeptide profiles depending on the origin of the beans. Additionally, by conducting in silico analysis of the elution times for 313 dipeptides, a machine learning model was constructed that accurately predicts dipeptide elution times. The DMT-(S)-Pro-OSu-UPLC/MS/MS method and the elution time prediction model developed in this study are expected to contribute to the understanding of dipeptide composition in foods.

SIL-IS LC-ESI-MS/MS method for simultaneous quick detection of amoxicillin and clavulanic acid in human plasma: Development, validation and its application to a pharmacokinetics study.

A liquid chromatography electrospray ionization tandem mass spectrometry method with amoxicillin-d4 as the stable isotope-labeled internal standard for simultaneous quick detection of amoxicillin and clavulanic acid in human plasma was developed and validated. Chromatographic separations were performed on a Hedera ODS-2 column (2.1 × 150 mm, 5μm). The mobile phases for gradient elution were aqueous solution containing 0.2% acetic acid (AA) (mobile phase A) together with organic phase solution (acetonitrile and methanol mixed solution, mobile phase B). Mass spectrometry was performed using negative electrospray ionization in multiple reaction monitoring mode. The target fragment ion pairs of amoxicillin, clavulanic acid and amoxicillin-d4 were m/z 364.1 → 223.1, 198.1 → 135.9 and 368.1 → 227.1, respectively. The linear ranges of this method were 40-5,000 ng/ml for amoxicillin and 30-2,500 ng/ml for clavulanic acid, with coefficient of determination > 0.9900. This method validation included selectivity, standard curve, lower limit of quantitation, accuracy, precision, recovery, matrix effect (hemolytic matrix and hyperlipidemic matrix), carryover, stability, dilution reliability and incurred sample reanalysis study. A successful application of this method was realized in a pharmacokinetic study after administration of amoxicillin-clavulanic acid potassium granules.

A Flavonoid Concentrate from Moringa Oleifera Lam. Leaves Extends Exhaustive Swimming Time by Improving Energy Metabolism and Antioxidant Capacity in Mice.

Moringa oleifera Lam. leaves contain various nutrients and bioactive compounds. The present study aimed to assess the anti-fatigue capacity of a flavonoids concentrate purified from M. oleifera Lam. leaves. The total flavonoids in the purified extract were analyzed by ultra-performance liquid chromatography electrospray ionization tandem mass spectrometry (UPLC-MS/MS). The mice were supplemented with purified M. oleifera Lam. leaf flavonoid-rich extract (MLFE) for 14 days. The weight-loaded forced swimming test was used for evaluating exercise endurance. The 90-min non-weight-bearing swimming test was carried out to assess biochemical biomarkers correlated to fatigue and energy metabolism. UPLC-MS/MS analysis identified 83 flavonoids from MLFE. MLFE significantly increased the swimming time by 60%. Serum lactate (9.9 ± 0.9 vs. 8.9 ± 0.7), blood urea nitrogen (BUN) (8.8 ± 0.8 vs. 7.2 ± 0.5), and nonesterified fatty acid (NEFA) (2.4 ± 0.2 vs. 1.7 ± 0.3) were significantly elevated; phosphoenolpyruvate carboxykinase (PEPCK), glucokinase (GCK), and nuclear factor erythroid 2-related factor 2 (Nrf2) mRNA expression were significantly downregulated; and heme oxygenase 1 mRNA expression was significantly upregulated in muscle after swimming. MLFE supplement significantly decreased serum lactate (8.0 ± 1.0 vs. 9.9 ± 0.9), BUN (8.6 ± 0.4 vs. 8.9 ± 0.8), and NEFA (2.3 ± 0.4 vs. 2.4 ± 0.2) and increased the protein and mRNA expression of GCK, PEPCK, and Nrf2. The enhancement of glucose metabolism and antioxidant function by MLFE contributes partly to its anti-fatigue action.

Quantitative analysis of phenolics in Trifolium pratense L. flowers and evaluation of antioxidant activity by sensory

Trifolium pratense L. flowers (TPF) were collected and dried in shade in this study. After extraction in methanol, a diluted solution was applied to the liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) device to determine the bioactive compounds quantitatively. Isoquercitrin (38.64 mg/g extract), coumarin (13.66 mg/g extract), and catechin (12.52 mg/g extract) were verified as major products. Antioxidant activity of TPF was performed using a potentiometric PVC membrane sensor to evaluate 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and total phenolic content of TPF. TPF inhibited the DPPH radical as 31.4 ± 0.02% at the 500-ppm concentration. However, the DPPH activity of gallic acid was determined as 81.43 ± 0.07% and 92.44 ± 0.1% at the TPF concentrations of 12.5 ppm and 25 ppm, respectively. In addition, the total phenolic content was calculated to be 82.4 ± 0.15 mg gallic acid eq/g extract. It was observed that TPF has the potential to be an antioxidant and a valuable source of isoquercitrin, coumarin, and catechin.

Application of marine sponges for biomonitoring active pharmaceutical ingredients (APIs) in coral reefs. Optimization of an SPME and ESI-LC-MS/MS method

Chemical pollution is a threat to coral reefs. To preserve them, it is crucial to monitor novel contaminants and assess the related risks. The occurrence of active pharmaceutical ingredients (APIs) in coral reefs has been poorly investigated until now. Under this light, we tested the use of the marine sponge Cf. Hyrtios as bio-monitors and conducted a pilot study in the Faafu Atoll (Maldives). Analyses were carried out by in vivo solid-phase microextraction (SPME) and liquid chromatography (LC) electrospray ionization (ESI) tandem mass spectrometry (MS/MS). Twelve APIs were selected for method optimization. Limits of quantitation (LOQs) were in the 0.6 and 2.5 ng/g range, accuracy between 86.5 % and 104.7 %, and precision between 3.0 % and 14.9 %. All the sponges located in the inner reefs resulted contaminated with at least one API. Gabapentin and Carbamazepine displayed the highest detection rates, while Ketoprofen had the highest concentration (up to 15.7 ng/g).

Production and biological activity of β-1,3-xylo-oligosaccharides using xylanase from Caulerpa lentillifera

In this study, β-1,3-xylanase (Xyl3088) was designed and prepared by constructing the expression vector plasmid and expressing and purifying the fusion protein. β-1,3-xylo-oligosaccharides were obtained through the specific enzymatic degradation of β-1, 3-xylan from Caulerpa lentillifera. The enzymolysis conditions were established and optimized as follows: Tris-HCl solution 0.05 mol/L, temperature of 37 °C, enzyme amount of 250 μL, and enzymolysis time of 24 h. The oligosaccharides' compositions and structural characterization were identified by thin-layer chromatography (TLC), ion chromatography (IC) and liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS). The IC50 values for scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2-azino-bis-3-ethyl-benzothiazoline-p-sulfonic acid (ABTS+), and superoxide anion radical (•O2−) were 13.108, 1.258, and 65.926 mg/mL for β-1,3-xylo-oligosaccharides, respectively, and 27.588, 373.048, and 269.12 mg/mL for β-1,4-xylo-oligosaccharides, respectively. Compared with β-1,4-xylo-oligosaccharides, β-1,3-xylo-oligosaccharides had substantial antioxidant activity and their antioxidant effects were concentration dependent. β-1,3-xylo-oligosaccharides also possessed a stronger anti-inflammatory effect on RAW 264.7 cells stimulated by lipopolysaccharide (LPS) than β-1,4-xylo-oligosaccharides. At a working concentration of 100 μg/mL, β-1,3-xylo-oligosaccharides inhibited the release of NO and affected the expression of IL-1β, TNF-α, and other proteins secreted by cells, effectively promoting the release of pro-inflammatory mediators by immune cells in response to external stimuli and achieving anti-inflammatory effects. Therefore, β-1,3-xylo-oligosaccharides are valuable products in food and pharmaceutical industries.

Simultaneous Detection Method of 11 Respiratory Drug Substances Including Theobromine, Oxymetazoline, etc. in Adulterated Dietary Supplements Using Liquid Chromatography–Electrospray Ionization–Tandem Mass Spectrometry and Liquid Chromatography–Quadrupole Time-of-Flight Mass Spectrometry Analysis

Abstract Recently, the demand for respiratory disease-related products has surged due to the influence of coronavirus disease 2019, prompting warnings about illegal dietary supplements containing unauthorized substances. Additionally, adulterated dietary supplements are continuously detected in open markets, posing significant public health safety problem. In this study, we developed and validated an analytical method for 11 respiratory drug substances using liquid chromatography–electrospray ionization–tandem mass spectrometry (LC–ESI–MS/MS) and proposed optimal conditions for LC–quadrupole time-of-flight MS (LC–QTOF-MS) to determine the fragmentation patterns of each substance. This method underwent thorough validation considering specificity, linearity, limits of detection and quantification, accuracy, precision, matrix effect, stability, etc. All results met international guidelines. These validated methods were applied to 52 dietary supplements advertised for treating respiratory diseases and enhancing respiratory function, among which one sample was found to contain 313.7 mg/g of theobromine. This determination was made by comparing the product ion ratios with the standards and subsequent quantification. To re-confirm the detected substances, their fragmentation patterns were compared with those of the standards using LC–QTOF-MS. In conclusion, the mass-based information, coupled with the LC–ESI–MS/MS method development, can be successfully applied to rapidly identify 11 respiratory drug substances in illegal dietary supplements used for respiratory disease treatment. The developed simultaneous detection method contributes to public health and safety improvements.

Chemical and Biological Characterization of the Ethyl Acetate Fraction from the Red Sea Marine Sponge Hymedesmia sp.

Hymedesmiidae is one of the largest families of marine sponges and stands out as an exceptional source of variable metabolites with diverse biological activities. In this study, the ethyl acetate fraction (HE) of a Hymedesmia sp. marine sponge from the Red Sea, Egypt, was analyzed for the first time using Ultra-performance liquid chromatography electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS) analysis. The analysis tentatively identified 29 compounds in this fraction, including the isolation and identification of six compounds (two pyrimidine nucleosides, one purine, and two pyrimidine bases in addition to one cerebroside) for the first time. The structures of the isolated compounds were established by 1D and 2D NMR (nuclear magnetic resonance), MS (mass spectrometry), and IR (infrared) spectroscopy. Furthermore, the cytotoxic, antioxidant, and antimicrobial activities of the ethyl acetate fraction were evaluated in vitro. The fraction exhibited strong DPPH scavenging activity with an IC50 of 78.7 µg/mL, compared to ascorbic acid as a positive control with an IC50 of 10.6 µg/mL. It also demonstrated significant cytotoxic activity with IC50 values of 13.5 µg/mL and 25.3 µg/mL against HCT-116 and HEP-2 cell lines, respectively, compared to vinblastine as a positive control with IC50 values of 2.34 µg/mL and 6.61 µg/mL against HCT-116 and HEP-2, respectively. Additionally, the ethyl acetate fraction displayed promising antibacterial activity against S. aureus with a MIC value of 62.5 µg/mL, compared to ciprofloxacin as a positive control with MIC values of 1.56 µg/mL for Gram-positive bacteria and 3.125 µg/mL for Gram-negative bacteria. It also exhibited activity against E. coli and P. aeruginosa with MIC values of 250 µg/mL and 500 µg/mL, respectively. Briefly, this is the first report on the biological activities and secondary metabolite content of the ethyl acetate fraction of Hymedesmia sp. marine sponge, emphasizing the potential for further research against resistant bacterial and fungal strains, as well as different cancer cell lines. The ethyl acetate fraction of Hymedesmia sp. is a promising source of safe and unique natural drugs with potential therapeutic and pharmaceutical benefits.

Tandem mass spectrometry imaging to assess illudin S distributions in Omphalotus illudens mushrooms

Poisoning metabolites within mushrooms typically exert varying physiological and biological effects; however, their distributions within mushrooms are seldom investigated. This study focused on imaging illudin S, a representative poisoning metabolite within Omphalotus illudens mushroom, using desorption electrospray ionization–tandem mass spectrometry (DESI–MS/MS) coupled with liquid chromatography–electrospray ionization–tandem mass spectrometry (LC–ESI–MS/MS). Initially, LC–ESI–MS/MS conditions were established for the selective detection of illudin S (m/z 247→159, positive mode) from extracted mushroom. Based on this MS/MS condition, each mushroom was divided into nine sections, and each section was subjected to specific DESI–MS/MS mode imaging (pixel size: 200 × 200 μm). The results revealed high concentrations of illudin S in the stalks of the mushrooms growing on trees. Further, re-evaluations using the LC–MS/MS assay revealed a seven-fold difference in the illudin S between the stalk and other regions. This study marks the first attempt at assessing toxic metabolite distributions within poisonous mushrooms, thus offering valuable insights including the efficient utilization of illudin analogs in biological applications.

Diesel Particulate Matter Permeation into Normal Human Skin and Intervention Using a Topical Ceramide Formulation

Introduction: Diesel particulate matter (DPM) emitted from diesel engines is a major source of air pollutants. DPM is composed of elemental carbon, which adsorbs organic compounds including toxic polycyclic aromatic hydrocarbons (PAHs). The skin, as well as airways, is directly exposed to DPM, and association of atopic dermatitis, psoriasis flares, and premature skin aging with air pollutant levels has been documented. In skin, the permeation of DPM and DPM-adsorbed compounds is primarily blocked by the epidermal permeability barrier deployed in the stratum corneum. Depending upon the integrity of this barrier, certain amounts of DPM and DPM-adsorbed compounds can permeate into the skin. However, this permeation into human skin has not been completely elucidated. Methods: We assessed the permeation of PAHs (adsorbed to DPM) into skin using ex vivo normal (barrier-competent) organ-cultured human skin after application of DPM. Two major PAHs, 2-methylnaphthalene and triphenylene, and a carcinogenic PAH, benzo(a)pyrene, all found in DPM, were measured in the epidermis and dermis using liquid chromatography electrospray ionization tandem mass spectrometry. In addition, we investigated whether a topical formulation can attenuate the permeation of DPM into skin. Results: 2-Methylnaphthalene, triphenylene, and benzo(a)pyrene were recovered from the epidermis. Although these PAHs were also detected in the dermis after DPM application, these PAH levels were significantly lower than those found in the epidermis. We also demonstrated that a topical formulation that has the ability to form more uniform membrane structures can significantly suppress the permeation of PAHs adsorbed to DPM into the skin. Conclusion: Toxic compounds adsorbed by DPM can permeate even barrier-competent skin. Hence, barrier-compromised skin, such as in atopic dermatitis, psoriasis, and xerosis, is even more vulnerable to air pollutants. A properly formulated topical mixture that forms certain membrane structures on the skin surface can effectively prevent permeation of exogenous substances, including DPM, into skin.

A high-dose of ursodeoxycholic acid treatment alleviates liver inflammation by remodeling gut microbiota and bile acid profile in a mouse model of non-alcoholic steatohepatitis

Ursodeoxycholic acid (UDCA) is a hydrophilic bile acid commonly used for treating cholestatic liver disease. However, its efficacy on non-alcoholic steatohepatitis (NASH) was controversial. This study aimed to investigate the impact of a high dosage of UDCA on a mouse model of NASH. Forty 6-week-old mice were fed a high-fat high-cholesterol (HFHC) diet for 12 weeks to establish a mouse model of NASH, and then divided into four groups: two groups transitioned to a normal diet, and the other two groups maintained the HFHC diet. Each group was administered a daily dosage of 300 mg/kg of UDCA or saline for a period of 8 weeks. The 16 s ribosomal RNA genes extracted from mice fecal pellets were sequenced using next-generation sequencing techniques. Serum bile acid profiles were quantified using liquid chromatography electrospray ionization tandem mass spectrometry method. The results showed that UDCA treatment ameliorated liver inflammation, without affecting liver fibrosis. UDCA treatment reduced the relative abundance of the genera Bacteroides, Parabacteroides, and Intestinimonas, whereas increased the relative abundance of the genera norank_f_Muribaculaceae and Parasutterella in the HFHC-maintaining groups. The serum levels of total bile acids and total primary bile acids increased, whereas those of endogenous primary bile acids decreased after UDCA treatment. Correlation analysis showed that primary bile acids were negatively correlated with the genera norank_f_Christensenellaceae and unclassified_f_Ruminococcaceae. In conclusion, a high dosage of UDCA can alleviate liver inflammation, probably by modifying the composition of gut microbiota and serum bile acid profiles in NASH mice.

Untargeted Metabolomic Profiling of Fructus Chebulae and Fructus Terminaliae Billericae

This study aims to identify the differences in metabolites between Fructus Chebulae (FC) and Fructus Terminaliae Billericae (FTB). Untargeted metabolomics was used to analyze differentially expressed metabolites (DEMs) with ultra-performance liquid chromatography–electrospray ionization–tandem mass spectrometry (UPLC-ESI-MS/MS). A grand total of 558 metabolites were detected, with 155 in positive ion mode and 403 in negative ion mode. Further differential analysis yielded 110 and 87 significantly different metabolites, which were mainly polyphenols, flavonoids, terpenoids, and alkaloids. Analysis of KEGG data showed that differentially expressed metabolites (DEMs) in both positive and negative ion modes were found to be enriched in 5 and 18 metabolic pathways, respectively, with metabolic pathways being the most enriched among them. In sum, this study reveals the differential metabolic profiles of FC and FTB and provides support for their further applications in traditional Chinese medicine.

Molecular identification and management of mycotoxigenic fungi in stored corn Grains

Mycotoxin-producing molds which considered as common maize grains contaminants are the genera Fusarium, Aspergillus and Penicillium. There are natural and safe ways to protect grains from mold contamination as the use of essential oils and chemical treatments. A total number of 25 samples were used to study the natural frequency in five governorates in Egypt, Molecular identification indicated that the most frequent fungi were Fusarium verticillioides, Aspergillus niger, Talaromyces verruculosus, Aspergillus flavus and Aspergillus terreus. The in vitro studies have been done to determine mycelial growth and spore germination inhibition of the two A. flavus; isolated and reference isolates. Thyme and acetic acid were tested in direct contact assay to study their effects on mycelial growth. Treatments showed significant impact on mycelial growth and spore germination inhibition of both A. flavus isolates. In the postharvest application treatments: as vapour and carrier contact assay, Thyme and Acetic acid were tested to determine their influence on growth and aflatoxin production in A. flavus isolates by liquid chromatography–electrospray ionization–tandem mass spectrometry (LC–ESI–MS/MS). Results indicated that both treatments were effective in inhibition of aflatoxin production in both vapour and carrier assays as they succeeded in reducing AFB1 while they inhibited completely the production of AFB2. The extent of the inhibition of aflatoxin production was dependent on the concentration and storage duration of treatments applied.

Onosma demirizii: Chemical composition, antioxidant and enzyme inhibitory activity

AbstractThe primary objectives of the present work were to determine the chemical composition, antioxidant potential and enzyme inhibitory activity of three extracts derived from Onosma demirizii (Boraginaceae), including methanol, water and ethyl acetate, and to chemically characterize the phytochemicals underlying this activity. A rapid, reproducible, simple, and sensitive method, which had been previously validated, was employed to identify 31 phenolics based on liquid chromatography electrospray ionization tandem mass spectrometry (LC‐ESI‐MS/MS). The conducted analysis of LC‐ESI‐MS/MS indicated that the methanol extract of O. demirizii was the richest in terms of both flavonoids and phenolics (42.75 mg GAEs/g extract and 59.90 mg QEs/g extract, respectively). The compounds with greatest abundance in methanol extract were hesperidin (177957 mg/g extract), chlorogenic acid (31815 mg/g extract), hyperoside (10199 mg/g extract), rosmarinic acid (8857 mg/g extract) and pinoresinol (2502 mg/g extract). Moreover, methanol extract exhibited the greatest activity in all antioxidant assays except for ferrous ion‐chelating assay. The EC50/IC50 values of the extract in CUPRAC and FRAP reducing power, phosphomolybdenum, DPPH and ABTS radical scavenging assays were determined to be 0.85, 1.47, 0.47, 1.78, and 1.67 mg/mL, respectively. However, the ferrous ion‐chelating assay was superior for water extract (1.07 mg/mL). Contrary to the results obtained from the assays of antioxidant activity, ethyl acetate extract was observed to be effective in enzymatic inhibition tests. The extract exhibited the highest activity against AChE and BChE (IC50 values 1.04 and 1.47 mg/mL, respectively). These extracts and compounds can be useful for the management of human diseases that are linked to oxidative stress.

Optimized Conditions for the Extraction of Phenolic Compounds from Aeginetia indica L. and Its Potential Biological Applications.

Aeginetia indica L., a parasitic root in the Orobanchaceae family, is used as a food colorant in traditional Thai desserts. However, scant information is available on its food applications as well as medicinal properties, while overharvesting by the local people has severely depleted wild plant populations. This research, thus, aimed to extract optimized total phenolic content (TPC) in varying extraction conditions using response surface methodology (RSM) and the Box-Behnken design (BBD). Results indicated that an extraction temperature of 90 °C, 80% (v/v) aqueous ethanol, and 0.5% (w/v) solid-to-liquid ratio yielded the highest TPC at 129.39 mg gallic acid equivalent (GAE)/g dry weight (DW). Liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) identified the predominant phenolics as apigenin (109.06 mg/100 g extract) and luteolin (35.32 mg/100 g extract) with trace amounts of naringenin and rutin. Under the optimal extraction condition, the plant extract exhibited antioxidant activities of 5620.58 and 641.52 µmol Trolox equivalent (TE)/g DW determined by oxygen radical absorbance capacity (ORAC) and ferric ion reducing antioxidant power (FRAP) assay, while the scavenging capacity of total radicals at 50% (SC50) was determined to be 135.50 µg/mL using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The plant extract also exhibited inhibitory activities against the key enzymes relevant to type II diabetes, obesity, and Alzheimer's disease, suggesting the potential for medicinal applications.

Phenolic Compound Profiles, Cytotoxic, Antioxidant, Antimicrobial Potentials and Molecular Docking Studies of Astragalus gymnolobus Methanolic Extracts.

Since Astragalus is a genus with many important medicinal plant species, the present work aimed to investigate the phytochemical composition and some biological activities of Astragalus gymnolobus. The methanolic fractions of four organs (stems, flowers, leaves, root and whole plant) were quantified and identified by Liquid Chromatography Electrospray Ionization Tandem Mass Spectrometry (LC-ESI-MS/MS) analysis. Hesperidin, hyperoside, p-hydroxybenzoic acid, protocatechuic acid and p-coumaric acid were identified as main compounds among the extracts. Among all cells, leaf methanol (Lm) extract had the highest cytotoxic effect on HeLa cells (IC50 = 0.069 μg/mL). Hesperidin, the most abundant compound in A. gymnolobus extract, was found to show a strong negative correlation with the cytotoxic effect observed in HeLa cells according to Pearson correlation test results and to have the best binding affinity to targeted proteins by docking studies. The antimicrobial activity results indicated that the most susceptible bacterium against all extracts was identified as Streptococcus pyogenes with 9-11 mm inhibition zone and 8192 mg/mL MIC value. As a result of the research, it was suggested that A. gymnolobus could be considered as a promising source that contributes to the fight against cancer.