Liquid Chromatography-mass Spectrometer Research Articles

Study on the fourof Pfaffia glomerata based on the metabolomics technology and comparison of Dangshen () in the equivalent substitution prescription.

To explore the four Qiof Pfaffia glomerata (PG) and endow this foreign folk herb with the properties of Chinese medicine, make it Chinese medicinal and localized, and could be used as a Chinese medicine. The normal group, six cold herb groups, six hot herb groups, six cool herb groups, PG prescription group (PGPG), and Dangshen (Radix Codonopsis) prescription group (CPPG) were prepared with corresponding concentrations of water extracts, these herb extracts were administered by gavage to Sprague-Dawley rats, and the 12 h urine at night on the 29th day of the SD rats in each group were collected, Liquid Chromatograph Mass Spectrometer system was used to analyze them, the best discriminant models for the medicinal properties of cold-hot and cold-cool were set up, so as to the medicinal properties of PGPG, CPPG and PG were predicted. Based on the Progenesis QI, Human Metabolome Database, Kyoto Encyclopedia of Genes and Genomes, MetaboAnalyst 5.0 database, we enriched metabolic pathway and classification mechanism of medicinal properties of cold-cool Chinese herbs and the molecular mechanism of PG prescription. We established a best model of cold-hot herbal discrimination in the positive ion mode, then the probability that PGPG was predicted cold property was 88.9%. Furthermore, a model of cold-cool herbal discrimination was established, then the probability of PGPG containing the cool property was 77.8%. In addition, typical cold and cool herbs mainly affected nine biomarkers such as tyrosine-proline, (R)-3',7-Dihydroxy-2',4'-dimethoxyisoflavane in rats. The regulation trend of PGPG on markers was basically as same as the cool herbs and mainly involved in regulating the two pathways of cytochrome P450 and purine metabolism. The results showed PGPG had a cool medicinal property as same as CPPG, and the regulation trend of PGPG on markers was consistent with cool herbs. Therefore, the medicine properties PG and CP should be consistent, and the Traditional Chinese Medicine property of PG was predicted to be neutral.

Chemically bonded CdBiO2Br/BiOI heterojunction with strong interfacial electric field for enhanced photocatalysis

Semiconductor-based photocatalysis shows a large potential for contaminant purification, however, a single semiconductor photocatalyst suffers from low utilization efficiency of photogenerated carriers, leading to inferior photocatalytic activity. Herein, CdBiO2Br@BiOI (CBOB@BiOI) heterojunction with a close interface interaction is prepared by a facile precipitation method at the ambient atmosphere. X-ray photoelectron spectroscopy and Density Functional Theory calculations on work function consistently disclose that the formation of CdBiI bonds at the interface induces the electron migration from BiOI to CdBiO2Br, which allows CBOB@BiOI heterojunction to have a strong interfacial electric field (IEF) for efficiently separating photocharges. In-situ Kelvin-probe Force Microscopy measurement demonstrates that CBOB@BiOI heterojunction shows a larger surface potential than CdBiO2Br and BiOI in dark and a potential decrease under illumination, which can be ascribed to the photoinduced electron migration within heterojunction driven by the IEF. Thus, the CBOB@BiOI heterojunction shows a much more efficient photocatalytic activity for the breakdown of tetracycline hydrochloride (TC), which is 2.44 and 3.99 times higher than CdBiO2Br and BiOI, respectively. Electron Paramagnetic Resonance test also confirms that the CBOB@BiOI heterojunction produces much more superoxide radicals and holes as reactive species than CdBiO2Br and BiOI. Furthermore, the latent degradation pathways of TC are investigated by Liquid Chromatograph Mass Spectrometer. This work may provide new ideas for constructing intimately bonded heterojunction photocatalysts with a strong IEF for efficient photocatalytic activity.

Platelet-derived growth factor receptor-α induces contraction knots and inflammatory pain-like behavior in a rat model of myofascial trigger points.

Myofascial trigger points (MTrPs) are the primary etiological characteristics of chronic myofascial pain syndrome (MPS). Receptor tyrosine kinases (RTKs) are associated with signal transduction in the central mechanisms of chronic pain but the role of RTKs in the peripheral mechanisms of MTrPs remains unclear. The present study aimed to identify RTKs expression in MTrPs and elucidate the molecular mechanisms through which platelet-derived growth factor receptor-α (PDGFR-α) induces contraction knots and inflammatory pain-like behavior in a rat model of myofascial trigger points. MTrPs tissue samples were obtained from the trapezius muscles of patients with MPS through needle biopsy, and PDGFR-α activation was analyzed by microarray, enzyme-linked immunosorbent assay (ELISA), and histological staining. Sprague-Dawley (SD) rats (male/female) were used to investigate PDGFR-α signaling, assessing pain-like behaviors with Randall-Selitto and nest-building tests. Muscle fiber and sarcomere morphologies were observed using histology and electron microscopy. The PDGFR-α binding protein was identified by co-immunoprecipitation (Co-IP), liquid chromatograph mass spectrometer (LC-MS), and molecular docking. PDGFR-α-related protein or gene levels, muscle contraction, and inflammatory markers were determined by Western blot and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). PDGFR-α phosphorylation levels were elevated in the MTrPs tissues of individuals with trapezius muscle pain and were positively correlated with pain intensity. In rats, PDGFR-α activation caused pain-like behaviors and muscle contraction via the janus kinase 2/signal transducer and activator of transcription-3 (JAK2/STAT3) pathway. JAK2/STAT3 inhibitors reversed the pain-like behaviors and muscle contraction induced by PDGFR-α activation. Collagen type I alpha 1 (COL1A1) binds to PDGFR-α and promotes its phosphorylation, which contributed to pain-like behaviors and muscle contraction. COL1A1-induced phosphorylation of PDGFR-α and the subsequent activation of the JAK2/STAT3 pathway may induce dysfunctional muscle contraction and increased nociception at MTrPs.

Boosted antibiotic elimination over 2D/2D mesoporous CeO2/BiOCl S-scheme photocatalyst

Exploring efficient photocatalysts holds significant importance for the prevention and treatment of antibiotic pollution. This research reports a 2D/2D CeO2/BiOCl S-scheme photocatalyst constructed by mesoporous CeO2 and BiOCl nanosheets (NSs). Efficient charge separation and transfer was achieved by the synergistic effect of large-area contact and S-scheme charge transfer mechanism, which significantly enhanced the photocatalytic performance of CeO2/BiOCl. Experimental results demonstrated that the CeO2/BiOCl photocatalyst displayed superior photocatalytic activity to the individual components, which could efficiently eliminate four types of antibiotics, namely tetracycline (TC), chlortetracycline (CTC), doxycycline (DOC), and oxytetracycline (OTC) under UV light irradiation. Particularly, the sample of 0.4CeO2/BiOCl exhibited the highest catalytic efficiency, with a TC degradation rate constant of 0.01524 min−1, which was 1.85 and 22.74 times higher than that of single CeO2 and BiOCl, respectively. Moreover, liquid chromatograph-mass spectrometer (LC-MS) analysis is employed to reveal the degradation pathways of TC. This work offers an insightful idea for the fabrication of novel S-scheme photocatalysts applied in environmental purification.

DETERMINATION OF POLYPHENOLIC COMPOUNDS IN PHYTOEXTRACTS WITH ANTIBACTERIAL PROPERTIES AND STUDY POTENTIAL EFFECTS

Objectives. The research work is a comparative study of the polyphenolic compounds and flavonoid content of the phytoextracts obtained from the ultrasonic extraction process (Stegler DG-360) with 95% ethanol and ethanol-propyleneglycol mixture (in 95 : 5 ratio) from the Clove buds (Caryophyllos aromaticus L. Myrtaceae), hibiscus flowers (Hibiscus sabdariffa L. (Hs, roselle; Malvaceae)) and common yarrow (Achillea millefolium L. Asteraceae) plants, which are rich in biologically active substances with high therapeutic effect, as well as their devoted to the investigation of antioxydant activity and antimicrobial potential. Material and methods. The research work was carried out in the Central Research and Application Laboratory of Ağrı İbrahim Çeçen University (MERLAB), Republic of Turkey, using a Japanese Shimadzu brand Mistral-AB SCIEX 4000 QTRAP liquid chromatograph-mass spectrometer device. Results.It was found that in both extraction processes, the active substances penetrated sufficiently from the medicinal-plant raw materials into the extractant. 20 names of compounds containing polyphenol, flavonoid and anthocyanin derivatives have been determined. However, the amount of active substances in the phytoextract obtained with the presence of the penetrate (propylene glycol) was higher. In particular, rutin ( 75.74 ± 4.91mg/g), quercetin (110.12 ± 1.30 mg/g), gallic acid (4503.19 ± 46.83mg/g), quinic acid (4041.99 ± 187.3 mg/g), chlorogenic acid (582.30 ± 1.30mg/g), vanilin (155.6g/g1 ± 3.95mg/g) prevailed. Conclusion. The research work proves once again that the studied phytoextracts are rich in polyphenolic compounds and flavonoids. The amount of biologically active substances in the phytoextract obtained with the ethanol-propylene glycol mixture which is the penetrate substance (in the ratio of 95:5) is higher than that of the other sample (with 95% ethanol). The resulting amount of biologically active substances is a clear proof that the phytoextract has sufficient antioxidant and antimicrobial properties.

Proteomic insights into extracellular vesicles in ALS for therapeutic potential of Ropinirole and biomarker discovery

BackgroundExtracellular vesicles (EVs) hold the potential for elucidating the pathogenesis of amyotrophic lateral sclerosis (ALS) and serve as biomarkers. Notably, the comparative and longitudinal alterations in the protein profiles of EVs in serum (sEVs) and cerebrospinal fluid (CSF; cEVs) of sporadic ALS (SALS) patients remain uncharted. Ropinirole hydrochloride (ROPI; dopamine D2 receptor [D2R] agonist), a new anti-ALS drug candidate identified through induced pluripotent stem cell (iPSC)-based drug discovery, has been suggested to inhibit ALS disease progression in the Ropinirole Hydrochloride Remedy for Amyotrophic Lateral Sclerosis (ROPALS) trial, but its mechanism of action is not well understood. Therefore, we tried to reveal longitudinal changes with disease progression and the effects of ROPI on protein profiles of EVs.MethodsWe collected serum and CSF at fixed intervals from ten controls and from 20 SALS patients participating in the ROPALS trial. Comprehensive proteomic analysis of EVs, extracted from these samples, was conducted using liquid chromatography/mass spectrometer (LC/MS). Furthermore, we generated iPSC-derived astrocytes (iPasts) and performed RNA sequencing on astrocytes with or without ROPI treatment.ResultsThe findings revealed notable disparities yet high congruity in sEVs and cEVs protein profiles concerning disease status, time and ROPI administration. In SALS, both sEVs and cEVs presented elevated levels of inflammation-related proteins but reduced levels associated with unfolded protein response (UPR). These results mirrored the longitudinal changes after disease onset and correlated with the revised ALS Functional Rating Scale (ALSFRS-R) at sampling time, suggesting a link to the onset and progression of SALS. ROPI appeared to counteract these changes, attenuating inflammation-related protein levels and boosting those tied to UPR in SALS, proposing an anti-ALS impact on EV protein profiles. Reverse translational research using iPasts indicated that these changes may partly reflect the DRD2-dependent neuroinflammatory inhibitory effects of ROPI. We have also identified biomarkers that predict diagnosis and disease progression by machine learning-driven biomarker search.ConclusionsDespite the limited sample size, this study pioneers in reporting time-series proteomic alterations in serum and CSF EVs from SALS patients, offering comprehensive insights into SALS pathogenesis, ROPI-induced changes, and potential prognostic and diagnostic biomarkers.

In vitro bioactivities and shelf life protective properties of sumac extracts against foodborne pathogens and computational analysis of sumac compounds

The aim of this study was to investigate the antibacterial, antibiofilm, antioxidant and shelf life protective potentials of infusion, decoction, and room temperature samples of sumac fruits prepared as used by the local people against three foodborne pathogens including Bacillus cereus, Escherichia coli O157:H7, and Staphylococcus aureus isolated from food samples. The room temperature samples of sumac showed a remarkable antibacterial activity (81.25%) against S. aureus. Infusion and decoction samples of sumac fruit showed an effective antibacterial activity (∼70%) against E. coli O157:H7. Moderate efficacy against B. cereus was observed in all treatment groups. Antibiofilm effects of sumac were observed against B. cereus and S. aureus, but not against E. coli O157:H7. The total antioxidant activity was found to be close to the reference compounds. The twenty-two phenolic and flavonoid chemical compounds (gallic acid, gentisic acid, protocatechuic acid, protocatechualdehyde, 4-OH-benzoic acid, salicylic acid, chlorogenic acid, cafeic acid, p-coumaric acid, ferulic acid, rosmarinic acid, sinapic acid, trans-cinnamic acid, rutin, resveratrol, myricetin, naringenin, quercetin, luteolin, kaempferol, apigenin, and chrysin) were identified by Liquid Chromatography Mass Spectrometer (LC-MS/MS) and these molecules were analyzed by computational analyses using SwissADME, admetSAR 3.0 and the AntiBac-Pred web tool. In addition, the antibacterial efficacy of sumac fruit extracts was tested on mixed Mediterranean salad samples to evaluate the shelf-life enhancing effect. The efficacy of sumac fruit against common foodborne pathogens suggests that the ethnobotanical use of sumac may provide protection against bacterial diseases and can be utilized as an additive and/or ingredient in the food industry.

Forensic analysis of hydrogen sulfide poisoning cases: Innovative LC-MS/MS methodology for accurate detection in human blood

Identification of hydrogen sulfide poisoning cases has long been a challenging issue in the field of forensic science. Due to the relatively limited histopathological features associated with hydrogen sulfide poisoning, traditional anatomy faces difficulties in accurately determining such cases. Additionally, existing detection methods have inherent limitations, including complex analytical processes and low sensitivity. This research uses the principle of the reaction between triazine and hydrogen sulfide to generate thiadiazine to measure hydrogen sulfide levels in the blood, applying this method to practical case examinations. A 0.2 mL blood sample is taken and diluted with 0.8 mL saturated borax solution. In a test tube, 1 mL acetonitrile solution containing 0.1 % formic acid is taken, followed by the sequential addition of 0.1 mL diluted solution and 0.1 mL 1 % triazine aqueous solution. After thorough mixing, the mixture is allowed to stand for 30 min, during which hydrogen sulfide undergoes a derivative reaction with triazine, producing thiazine. Subsequently, the sample undergoes centrifugation and membrane filtration, and the resulting solution is analyzed using Liquid Chromatograph Mass Spectrometer. The results reveal a strong linear relationship of hydrogen sulfide within the concentration range of 10 to 2000 ng/mL, with an R2 of 0.9989. The detection limit is 3 ng/mL, and the quantification limit is 10 ng/mL. In six cases of hydrogen sulfide poisoning, the presence of hydrogen sulfide in the blood of all deceased individuals is detected, with concentrations ranging from 0.25 to 0.79 μg/mL. For the first time, this study establishes an LC-MS/MS method for determining hydrogen sulfide in blood, meeting the detection requirements for hydrogen sulfide poisoning cases.

Mechanism of enhanced degradation of antibiotic wastewater by three-dimensional electrocatalytic oxidation system: Coconut shell biochar as particle electrode

A porous particle electrode, coconut shell biochar (CBC), was prepared using coconut shell as raw material and applied to the treatment of tetracycline (TC) wastewater. Exploring the three-dimensional electrocatalytic oxidation system using a series of key factors such as pH (2−10), current density (20–60 mA/cm2), CBC particle size (0.88–2.36 mm), CBC dosage (3–13 g/L), electrolyte concentration (5000–10,000 mg/L), and electrode spacing (3–5 cm). The optimal conditions for these parameters were 10, 50 mA/cm2, 1.4–1.7 mm, 7 g/L, 8000 mg/L, and 4 cm. Under these conditions, the degradation of TC conformed to pseudo-first-order kinetics. The chemical oxygen demand (COD) and TC removal rates reached 84.01 % and 99.18 % within 45 min, while the two-dimensional system only achieved 29.27 % and 39.83 %, respectively. The degradation mechanism of TC was determined based on the production of H2O2 and •OH. The adsorbed saturated CBC might be regenerated through electrochemical reactions, inducing further adsorption, and forming numerous micro electrolysis cells to promote the production of free radicals, thereby boosting TC mineralization. Finally, the high-performance liquid chromatography-mass spectrometer was applied to identify the transformation products and degradation pathways of TC. Additionally, the CBC still showed excellent catalytic degradation effect after being reused for 4 times. Therefore, this study makes it possible to prepare an efficient and low-cost electrocatalyst for the treatment of antibiotic wastewater, as well as for further understanding the electrocatalytic mechanism, conversion products, and degradation pathways of TC in wastewater.

Physiological Adaptation of Fenneropenaeus chinensis in Response to Saline-Alkaline Stress Revealed by a Combined Proteomics and Metabolomics Method.

The rapid development of the mariculture industry has been hindered by limited coastal aquaculture space. To utilize the abundant inland saline-alkaline water, we studied the physiological effects of high carbonate alkalinity stress and high pH stress on Fenneropenaeus chinensis. The study employed quantitative proteomics by tandem mass tag (TMT) and non-targeted metabolomics analysis using a liquid chromatograph mass spectrometer (LC-MS) to understand the physiological and biochemical adaptive mechanisms of the hepatopancreas of F. chinensis in response to saline-alkaline stress at the molecular level. We designed two stress groups as follows: a high carbonate alkalinity (CA) group and a combined high carbonate alkalinity and high pH (CP) group. The study found that the protein and metabolic profiles of the two stress groups were changed, and the CP group, which was exposed to dual stresses, incurred more severe damage to the hepatopancreas compared to that of the CA group. After exposure to CA and CP, the hepatopancreas of F. chinensis showed significant alterations in 455 proteins and 50 metabolites, and 1988 proteins and 272 metabolites, respectively. In addition, F. chinensis upregulated the level of energy metabolism in the hepatopancreas to defend against osmotic imbalance caused by CA or CP stress, which was demonstrated by the significant upregulation of important proteins and metabolites in glycolysis, pyruvate metabolism, TCA cycle, and fatty acid oxidation. Additionally, pattern recognition receptors, the phenol oxidase system, and various immune-related metabolic enzymes and metabolites were also affected. The immune homeostasis of F. chinensis was affected by the alteration of the antioxidant system following exposure to CA or CP. These findings provide valuable information for F. chinensis saline-alkaline water cultivation practices.

Metabolomics reveals altered metabolites in cirrhotic patients with severe portal hypertension in Tibetan population.

Portal hypertension (PHT) presents a challenging issue of liver cirrhosis. This study aims to identify novel biomarkers for severe PHT (SPHT) and explore the pathophysiological mechanisms underlying PHT progression. Twenty-three Tibetan cirrhotic patients who underwent hepatic venous pressure gradient (HVPG) measurement were included. Eleven patients had an HVPG between 5 mmHg and 15 mmHg (MPHT), while 12 had an HVPG ≥16 mmHg (SPHT). Peripheral sera were analyzed using liquid chromatograph-mass spectrometer for metabolomic assessment. An additional 14 patients were recruited for validation of metabolites. Seven hundred forty-five metabolites were detected and significant differences in metabolomics between MPHT and SPHT patients were observed. Employing a threshold of p < 0.05 and a variable importance in projection score >1, 153 differential metabolites were identified. A significant number of these metabolites were lipids and lipid-like molecules. Pisumionoside and N-decanoylglycine (N-DG) exhibited the highest area under the curve (AUC) values (0.947 and 0.9091, respectively). Additional differential metabolites with AUC >0.8 included 6-(4-ethyl-2-methoxyphenoxy)-3,4,5-trihydroxyoxane-2-carboxylic acid, sphinganine 1-phosphate, 4-hydroxytriazolam, 4,5-dihydroorotic acid, 6-hydroxy-1H-indole-3-acetamide, 7alpha-(thiomethyl)spironolactone, 6-deoxohomodolichosterone, glutaminylisoleucine, taurocholic acid 3-sulfate, and Phe Ser. Enzyme-linked immunosorbent assay further confirmed elevated levels of sphinganine 1-phosphate, N-DG, and serotonin in SPHT patients. Significant disruptions in linoleic acid, amino acid, sphingolipid metabolisms, and the citrate cycle were observed in SPHT patients. Pisumionoside and N-DG are identified as promising biomarkers for SPHT. The progression of PHT may be associated with disturbances in lipid, linoleic acid, and amino acid metabolisms, as well as alterations in the citrate cycle.

Development of UPLC–MS/MS method for the simultaneous quantification of valproic acid and phenytoin in human plasma and application to study pharmacokinetic interaction in epilepsy patients

Valproic acid and phenytoin are two prevalent antiepileptic medications known for their narrow indices and propensity for cardiovascular and respiratory system toxicity. Therefore, therapeutic drug monitoring (TDM) of valproic acid (VAL) and phenytoin (PHE) concentrations in patient plasma is extremely beneficial for improving clinical choices, avoiding adverse reactions, and optimizing treatment for individual patients. In this study, a rapid and sensitive ultra-performance liquid chromatographic tandem mass spectrometer (UPLC-MS/MS) method was developed and validated for the simultaneous quantitative determination of valproic acid (VAL) and phenytoin (PHE) in human plasma. Negative electron spray ionization (ESI-) mode with selective ion recording (SIR) was employed to determine the transitions of m/z 142.98 and m/z 250.93 for VAL and PHE, respectively. The internal standard (IS) betamethasone (BETA) was ionized using positive electron spray ionization (ESI+) and detected by multi-reaction monitoring (MRM) mode to obtain precursor ions and specific fragment ions for quantification, and the MRM transition was chosen to be m/z 393.17 → 355.16. The separation was performed using a Phenomenex Synergi Hydro-RP (4 μm, 250 × 4.6 mm, I.D.) with an isocratic mobile phase consisting of acetonitrile – water (75:25, v/v) at a flow rate of 0.8 mL/min. The column temperature was maintained at 25 °C. The lower limit of quantification of VAL and PHE was 3.6 μg/mL and 0.72 μg/mL, respectively, which resulted in a recovery of more than 85 % for most analytes. According to US-FDA bioanalytical technique validation, the specificity, intra- and inter-day precision and accuracy, matrix effect, carryover, dilution, and stability of all analytes were within acceptable ranges. This analytical method was successful in evaluating the levels of valproic acid and phenytoin in human plasma from epileptic patients.

THC Content on a Dry Weight Basis: Implications for Hemp Legality.

The 2018 Farm Bill defines hemp as Cannabis sativa L. with a tetrahydrocannabinol (THC) concentration not more than 0.3% on a dry weight basis where THC is implied to be total THC (THCTotal) including both acid (Δ9-THCA) and neutral (Δ9-THC) forms. Effect of temperature and mass were studied to determine the quickest time to prepare fresh hemp suitable for grinding without affecting THCTotal. Proficiency testing program data were also analyzed to compare THCTotal contents on a dry versus wet weight basis. Fresh hemp of 150 and 400 g were freeze-dried or heat-treated at 50 °C, 60 °C, and 70 °C for various lengths of time up to 72 hours. Ground hemp was analyzed for moisture content via AOAC 934.01 and THCTotal via liquid chromatography/mass spectrometer (LC/MS) or gas chromatography with flame ionization detection (GC/FID). A data set analyzed from a proficiency testing program included moisture and THCTotal from 20 to 67 laboratories on 12 analytical samples circulated from 2020 through 2022. The quickest drying time of 24 h occurred at 70 °C with 150 g. These conditions did not affect THCTotal content on a dry weight basis. Twelve proficiency testing program analytical samples ranged from 5.8 to 11.4% moisture and 0.144 to 0.399% THCTotal on a wet weight basis. An increase in reported THCTotal on a dry weight basis compared to a wet weight basis ranged from 0.002 to 0.027% with a significant difference occurring in only one analytical sample. Suitable condition for drying hemp without altering THCTotal content was 24 h at 70 °C. Determining residual moisture in oven-dried ground hemp to calculate THCTotal content on a dry weight basis provides no benefit given minimal difference between contents on dry versus wet weight bases, interlaboratory variability, and terpene volatilization.

Characterization of cotinine degradation in a newly isolated Gram-negative strain Pseudomonas sp. JH-2.

Cotinine, the primary metabolite of nicotine in the human body, is an emerging pollutant in aquatic environments. It causes environmental problems and is harmful to the health of humans and other mammals; however, the mechanisms of its biodegradation have been elucidated incompletely. In this study, a novel Gram-negative strain that could degrade and utilize cotinine as a sole carbon source was isolated from municipal wastewater samples, and its cotinine degradation characteristics and kinetics were determined. Pseudomonas sp. JH-2 was able to degrade 100mg/L (0.56 mM) of cotinine with high efficiency within 5 days at 30 ℃, pH 7.0, and 1% NaCl. Two intermediates, 6-hydroxycotinine and 6-hydroxy-3-succinoylpyridine (HSP), were identified by high-performance liquid chromatography and liquid chromatograph mass spectrometer. The draft whole genome sequence of strain JH-2 was obtained and analyzed to determine genomic structure and function. No homologs of proteins predicted in Nocardioides sp. JQ2195 and reported in nicotine degradation Pyrrolidine pathway were found in strain JH-2, suggesting new enzymes that responsible for cotinine catabolism. These findings provide meaningful insights into the biodegradation of cotinine by Gram-negative bacteria.

PANI/GO and Sm co-modified Ti/PbO2 dimensionally stable anode for highly efficient amoxicillin degradation: Performance assessment, impact parameters and degradation mechanism

The abuse and uncontrolled discharge of antibiotics present a severe threat to environment and human health, necessitating the development of efficient and sustainable treatment technology. In this work, we employ a facile one-step electrodeposition method to prepare polyaniline/graphite oxide (PANI/GO) and samarium (Sm) co-modified Ti/PbO2 (Ti/PbO2-PANI/GO-Sm) electrode for the degradation of amoxicillin (AMX). Compared with traditional Ti/PbO2 electrode, Ti/PbO2-PANI/GO-Sm electrode exhibits more excellent oxygen evolution potential (2.63 V) and longer service life (56 h). In degradation experiment, under optimized conditions (50 mg L−1 AMX, 20 mA cm−2, pH 3, 0.050 M Na2SO4, 25 °C), Ti/PbO2-PANI/GO-Sm electrode achieves remarkable removal efficiencies of 88.76% for AMX and 79.92% for chemical oxygen demand at 90 min. In addition, trapping experiment confirms that ·OH plays a major role in the degradation process. Based on theoretical calculation and liquid chromatography-mass spectrometer results, the heterocyclic portion of AMX molecule is more susceptible to ·OH attacks. Thus, this novel electrode offers a sustainable and efficient solution to address environmental challenges posed by antibiotic-contaminated wastewater.

Effects of taurine on metabolomics of bovine mammary epithelial cells under high temperature conditions.

High temperature induces heat stress, adversely affecting the growth and lactation performance of cows. Research has shown the protective effect of taurine against hepatotoxicity both in vivo and in vitro. This study aimed to investigate the effect of taurine on the metabolomics of mammary epithelial cells of dairy cows under high-temperature conditions. Mammary epithelial cells were exposed to 0 mmol/L (HS, control), 8 mmol/L (HT-8), and 32 mmol/L (HT-32) of taurine, then incubated at 42°C for 6 h. Metabolomics analysis was conducted using Liquid Chromatograph Mass Spectrometer (LC-MS). Compared with the HS group, 2,873 and 3,243 metabolites were detected in the HT-8 group in positive and negative ion modes. Among these, 108 and 97 metabolites were significantly upregulated in positive and negative ion modes, while 60 and 166 metabolites were downregulated. Notably, 15 different metabolites such as palmitic acid, adenine and hypoxanthine were screened out in the HT-8 group. Compared with the HS group, 2,873 and 3,243 metabolites were, respectively, detected in the HT-32 group in the positive and negative ion modes. Among those metabolites, 206 metabolites were significantly up-regulated, while 206 metabolites were significantly downregulated in the positive mode. On the other hand, 497 metabolites were significantly upregulated in the negative mode, while 517 metabolites were reported to be downregulated. Noteworthy, 30 distinct metabolites, such as palmitic acid, phytosphingosine, hypoxanthine, nonanoic acid, and octanoic acid, were screened out in the HT-32 group. KEGG enrichment analysis showed that these metabolites were mainly involved in lipid metabolism, purine metabolism and other biological processes. Overall, our study indicates that taurine supplementation alters the metabolites primarily associated with purine metabolism, lipid metabolism and other pathways to alleviate heat stress in bovine mammary epithelial cells.

Highly efficient activation of sulfite by oxygen vacancies-enriched ZnCe0.4Fe1.6O4 for methylparaben degradation

The exploitation of a novel catalyst was of great significance for sulfate radical-based advanced oxidation processes (AOPs) using sulfite as the precursor of sulfate radical. Herein, oxygen vacancies-enriched ZnCe0.4Fe1.6O4 was prepared and applied to activate sulfite for the degradation of methylparaben (MeP). ZnCe0.4Fe1.6O4 showed superior catalytic activity than that of ZnFe2O4, allowing an 85.2 % removal efficiency of MeP within 60 min. The initial pH showed a significant effect on the catalytic performance, and about 92.1 % of MeP could be removed at pH of 9.56 in ZnCe0.4Fe1.6O4/sulfite system. The quenching experiments and EPR tests verified SO4− and OH were the main reactive oxygen species (ROS) in ZnCe0.4Fe1.6O4/sulfite system. The catalytic mechanism was elucidated further by X-ray photoelectron spectroscopy (XPS) analysis of ZnCe0.4Fe1.6O4 before and after the reaction. The recycles of Zn2+/Zn3+, Fe2+/Fe3+ and Ce3+/Ce4+ were the key factor for the activation of sulfite, and oxygen vacancies on catalyst surface promoted the activation of sulfite. The degradation intermediates of MeP were determined by a liquid chromatography-mass spectrometer (LC-MS) and the degradation pathway was proposed. The reusability of ZnCe0.4Fe1.6O4 was evidenced by the recycling experiments. In addition, ZnCe0.4Fe1.6O4/sulfite system exhibited excellent applicability in treating other organic contaminants.

Cellular pharmacokinetic of methotrexate and its modulation by folylpolyglutamate synthetase and γ-glutamyl hydrolase in tumor cells.

Clinical studies showed that prolonged infusion of methotrexate (MTX) leads to more severe adverse reactions than short infusion of MTX at the same dose. We hypothesized that it is the saturation of folate polyglutamate synthetase (FPGS) at high MTX concentration that limits the intracellular synthesis rate of methotrexate polyglutamate (MTX-PG). Due to a similar accumulation rate, a longer infusion duration may increase the concentration of MTX-PG and, result in more serious adverse reactions. In this study, we validated this hypothesis. A549, BEL-7402 and MHCC97H cell lines were treated with MTX at gradient concentrations. Liquid chromatograph-mass spectrometer (UPLC-MS/MS) was used to quantify the intracellular concentration of MTX-PG and the abundance of FPGS and γ-glutamyl hydrolase (GGH). High quality data were used to fit the cell pharmacokinetic model. Both cell growth inhibition rate and intracellular MTX-PG concentration showed a nonlinear relationship with MTX concentration. The parameter Vmax in the model, which represents the synthesis rate of MTX-PG, showed a strong correlation with the abundance of intracellular FPGS. According to the model fitting results, it was confirmed that the abundance of FPGS is a decisive factor limiting the synthesis rate of MTX-PG. The proposed hypothesis was verified in this study. In addition, based on the intracellular metabolism, a reasonable explanation was provided for the correlation between the severity of adverse reactions of MTX and infusion time. This study provides a new strategy for the individualized treatment and prediction of efficacy/side effects of MTX.

Comparative study of antioxidant activities of Allium sativum (a novel variety, HG17) and Allium ampeloprasum (SMG): Revealing the higher potential of HG17 and analyzing its phytochemicals.

Garlic, belonging to the genus Allium, is renowned for its rich antioxidant potential. Snow Mountain garlic (SMG) (Allium ampeloprasum) has been traditionally used for medicinal purposes because of its higher antioxidant potential. Considering its potential in medical therapies, we compared the antioxidant activity of SMG with a novel variety of Allium sativum, Hisar garlic 17 (HG17). Comparative antioxidant activity data (2,2-diphenyl-1-picrylhydrazyl and 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) revealed the higher antioxidant activity of HG17 than SMG, which prompted us to conduct a comprehensive phytochemical investigation to elucidate the factors contributing to antioxidant potential of HG17. To get a detailed antioxidant and phytoconstituents profiling, we differentially extracted HG17 by processing it in different forms (fresh, dry, heated, and aged) with two solvents (50% methanol and n-butanol). Our data (antioxidant activities, total phenolics, and flavonoids) showed that dry garlic methanolic extract (DgM) had maximum potential than other HG17 forms/solvents, which concludes that different extraction techniques had direct impact on the phenolics/flavonoids and antioxidant potential of the extracts. Further, phytochemical analysis of HG17 extracts by high resolution liquid chromatograph mass spectrometer quadrupole time of flight validated the maximum potential of DgM. LCMS revealed the presence of garcimangosone C, osmanthuside A, and protoaphin aglucone polyphenols exclusively in DgM compared to other HG17 extracts, which possibly contributing in its high antioxidant potential. The overall differential extraction and LCMS data of HG17 strongly depict that it may be used as an alternative of SMG under diverse medical applications. HG17 higher antioxidant potential and rich array of unique phytochemicals make it valuable for food and pharmaceutical industries to integrate into functional foods/therapeutics. PRACTICAL APPLICATION: Garlic unique phytochemical composition and its remarkable ability to scavenge different radicals make it valuable therapeutic asset to mitigate diseases associated with oxidative stress. SMG is well known for its anti-arthritic and anti-inflammatory properties. HG17 showed higher antioxidant potential than SMG and can be used as an alternative of SMG for anti-arthritic properties.

Comprehensive insights into the mechanism of flavor formation driven via inoculation with mixed starter cultures in dry-fermented tilapia sausages: Integration of macrogenomics, volatilomics, and lipidomics

To investigate the mechanisms of flavor formation in dry-fermented tilapia sausages, the volatiles, bacterial community, and lipid composition during fermentation were analyzed using gas chromatography-ion mobility spectrometry, 16S high throughput sequencing, and ultra-performance liquid chromatography-mass spectrometer. Pediococcus pentosaceus, Staphylococcus xylosus, and Staphylococcus carnosus became dominant bacteria during the fermentation. A total of 66 volatiles and 293 lipids (48 differential lipids) were identified. PC and PE content decreased. Aldehyde and 1-octen-3-ol content decreased. Most esters and ketones content increased during fermentation. Six metabolic pathways associated with differential lipids were identified by enrichment analysis. Glycerophospholipid metabolism was the main metabolic pathway. Correlation analysis revealed that PC and PE were precursors for volatiles, including PC 16:0/18:2 and PE 18:0/22:6. The dominant bacteria facilitate the hydrolysis of PC and PE, leading to the formation of esters and ketones. This study provides a theoretical basis for the targeted regulation of fermented sausage flavors.