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Objective To develop a powerful integrated strategy based on liquid chromatography coupled with mass spectrometry (LC-MS) systems for the comprehensive characterization and quantification of multiple components of herbal medicines. Methods Firstly, different mobile phase additives, analysis time, and MS acquisition modes were orthogonally tested with liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (LC-QTOF/MS) in order to detect as many components of Gelsemium elegans as possible with high peak intensity. Secondly, several data mining strategies, including database searching, diagnostic ion filtering and neutral loss filtering, were utilized to perform chemical profiling. Subsequently, this study focused on the quantification and validation of the performance of a liquid chromatography-triple mass spectrometry (LC-QqQ/MS) assay based on derivative multiple reaction monitoring (DeMRM). Results A total of 147 components from G. elegans were characterized, among them 116 nontarget components were reported for the first time. A sensitive and reproducible LC-QqQ/MS method was successfully developed and validated for the simultaneous relative quantification of 41 components of G. elegans. This LC-QqQ/MS method was then applied to compare the contents of components in the roots, stems and leaves. Conclusion The present integrated strategy would significantly contribute to chemical studies on herbal medicine, and its utility could be extended to other research fields, such as metabolomics, quality control, and pharmacokinetics.

Gelsemium elegans Benth (G. elegans) is highly toxic to humans and rats, but has insecticides and growth promoting effects on pigs and goats. G. elegans is widely used in livestock, but its in vivo dynamics are entirely unknown. Hence, we investigated the toxicokinetic profiles of G. elegans alkaloids after a single oral dose of G. elegans to pigs (1.0 g/kg) and rats (0.1 g/kg). The results indicated that rats were more susceptible to the toxicity of G. elegans than pigs. The toxicokinetic parameters of 22 and 6 components were obtained in pigs and rats, respectively. The components included 9 and 5 gelsedine-type alkaloids in pigs and rats, respectively. The Tmax results of the 5 gelsedine-type alkaloids indicated that these alkaloids were rapidly absorbed in pigs and rats. The T1/2 values of the 5 gelsedine-type alkaloids indicated that the elimination rates of these alkaloids in pigs were slower than those in rats. In addition, the Cmax and AUC results indicated that the degrees of absorption and exposure of most alkaloids in pigs were higher than those in rats except GS-2. However, the Cmax value of GS-2 (11-methoxy-14-hydroxygelsenicine) in rats was greater than that of pigs, and the Cmax value of 14-hydroxygelsenicine in pigs was merely greater than 3 times that of rats. The present results suggested that the cause of the toxicological differences species of G. elegans might be related to the degrees of absorption and exposure of gelsedine-type alkaloids, especially for the 14-hydroxygelsenicine and GS-2 in different animals.

Background: Gelsemium elegans (G. elegans) (2n = 2x = 16) is genus of flowering plants belonging to the Gelsemicaeae family. Method: Here, a high-quality genome assembly using the Oxford Nanopore Technologies (ONT) platform and high-throughput chromosome conformation capture techniques (Hi-C) were used. Results: A total of 56.11 Gb of raw GridION X5 platform ONT reads (6.23 Gb per cell) were generated. After filtering, 53.45 Gb of clean reads were obtained, giving 160 × coverage depth. The de novo genome assemblies 335.13 Mb, close to the 338 Mb estimated by k-mer analysis, was generated with contig N50 of 10.23 Mb. The vast majority (99.2%) of the G. elegans assembled sequence was anchored onto 8 pseudo-chromosomes. The genome completeness was then evaluated and 1338 of the 1440 conserved genes (92.9%) could be found in the assembly. Genome annotation revealed that 43.16% of the G. elegans genome is composed of repetitive elements and 23.9% is composed of long terminal repeat elements. We predicted 26,768 protein-coding genes, of which 84.56% were functionally annotated. Conclusion: The genomic sequences of G. elegans could be a valuable source for comparative genomic analysis in the Gelsemicaeae family and will be useful for understanding the phylogenetic relationships of the indole alkaloid metabolism. KEY WORDS: Gelsemium elegans, Nanopore sequencing, Genome assembly, Hi-C, Genome annotation, Monoterpene indole alkaloid

Microbial reduction decolorization is a promising strategy for cationic azo dye pollution remediation, but the reduction mechanism is unclear yet. In this work, the anaerobic reduction decolorization mechanism of cationic red X-GRL (X-GRL) by Shewanella oneidensis MR-1 (MR-1) was investigated from both intracellular and extracellular aspects. The exogenous additional riboflavin treatment test was used to analyze the extracellular reduction mechanism of X-GRL, and the actual role of riboflavin during the reduction of X-GRL was identified by three-dimensional fluorescence analysis for the first time. The proteinase K and the electron competitor treatment tests were used to analyze the intracellular reduction mechanism of X-GRL. Moreover, the effect of external environment on the reduction mechanism of X-GRL was elucidated by the decolorization performance of MR-1 wild type and its mutants, ΔomcA/mtrC, ΔmtrA, ΔmtrB and ΔcymA, under different external pH conditions. The results indicated that X-GRL could be decolorized by MR-1 in both extracellular and intracellular spaces. The extracellular decolorization of X-GRL could be caused by Mtr respiratory pathway or the indirect reduction of riboflavin, while the intracellular decolorization might occur due to the intracellular reduction depending on CymA pathway and a NADH-dependent reduction catalyzed by intracellular azoreductases. Furthermore, the proportion of extracellular decolorization decreased, whereas that of intracellular decolorization increased as the environmental pH rose.

Objective To study whether sevoflurane pretreatment inhibits the myocardial apoptosis caused by hypoxia reoxygenation through AMPK pathway. Methods H9c2 myocardial cell lines were cultured and divided into control group (C group), hypoxia reoxygenation group (H/R group), sevoflurane pretreatment + hypoxia reoxygenation group (SP group) and sevoflurane combined with Compound C pretreatment + hypoxia reoxygenation group (ComC group), and the cell proliferation activity and apoptosis rate, myocardial enzyme levels in culture medium as well as the expression of apoptosis genes and p-AMPK in cells were determined. Results p-AMPK expression in cells of H/R group was significantly lower than that of C group, SP group was significantly higher than that of H/R group; cell proliferation activity value and Bcl-2 expression in cells of H/R group were significantly lower than those of C group, SP group were significantly higher than those of H/R group, ComC group were significantly lower than those of SP group; apoptosis rate, LDH, CK and AST levels as well as the Bax and Caspase-3 expression in cells of H/R group were significantly higher than those of C group, SP group were significantly lower than those of H/R group, ComC group were significantly higher than those of SP group. Conclusions Sevoflurane pretreatment can activate AMPK signaling pathway to inhibit the myocardial apoptosis caused by hypoxia reoxygenation.

In the present study, Shewanella oneidensis MR-1 was successfully exploited to produce CuS nanocrystals not only as a biotemplate but also as a supplier of sulfur source. The biogenic H 2 S produced via the thiosulfate reduction in periplasm grabbed Cu(II) ions bound with extracellular polymeric substance of Shewanella and precipitated as monodisperse CuS nanoparticles extracellularly. These nanoparticles aggregated in the extracellular matrix gradually and then formed CuS nanorods. Ultimately, a complex hollow CuS microshell self-assembled on the cell surface was observed for the first time. The biogenic CuS microshell could significantly enhance the adsorption ability of S. oneidensis MR-1 toward Cr(VI). This work may facilitate a better understanding about the biosynthesis mechanism of nanomaterials and contribute to the application in environmental remediation.

Ethnopharmacological relevance The genus Albizia (Leguminosae) comprises about 150 species and some species have been used for the treatment of rheumatism, stomachache, cough, diarrhea, and wounds in traditional and local medicine. The aim of the review: This review article documents and critically assesses the current status of the traditional uses, phytochemistry, pharmacology, and toxicology of the Albizia species. Materials and methods All provided literatures on the Albizia species were searched using the electronic databases (e.g. Web of Science, Elsevier, Springer, PubMed, ACS, CNKI, Google Scholar, and Baidu Scholar), books, and theses with keywords of ‘Albizia’ and ‘Albizzia’. Results Albizia species have been used for melancholia, insomnia, wounds, fever, abscesses, diabetes, headache, stomachache, diarrhea, cough, rheumatism, snake bite, malaria, and parasitic infection in traditional and local medicine. These plants mainly contain triterpenoid saponins, flavonoids, lignanoids, alkaloids, phenolic glycosides, etc. Albizia species have been demonstrated to possess various pharmacological activities. Among them, the antidiabetic, anti-inflammatory, antifertility, antianxiety, antidepressant, and anti-fever properties are consistent with the traditional and local applications of the Albizia species. Conclusions The traditional and local uses of Albizia species have been partially demonstrated by the pharmacological investigation. However, some traditional applications have not been assessed scientifically due to incomplete methodologies and ambiguous findings. Moreover, no clinical evidences support the health benefits of these plants. The systematic and comprehensive preclinical studies and clinical trials are still required to verify the pharmacological activities, clinical efficacy, and safety of Albizia species.

Electrochemically active bacteria (EAB) have attracted great attention in the pollutant biodegradation due to its unique extracellular reduction capacity. But the reduction ability of biogenic electron is insufficient to achieve degradation of many pollutants. Thus, in the present study, Shewanella oneidensis MR-1 was firstly employed to biofabricate visible light-responsive CdS nanocrystals. A bio-photoelectric reductive degradation system (BPRDS) which established by combining S. oneidensis MR-1 and self-synthesized CdS achieved efficient degradation of trypan blue under photoexcitation. Chemical analyses revealed that the cleavage of azo bonds resulted in the decolorization. Blocking of transmembrane electron transfer significantly decreased the decolorization efficiency of BPRDS. After incubating for 5 h, the removal of trypan blue in BPRDS inoculated with ΔmtrA, ΔmtrB, ΔmtrC/omcA, or ΔcymA mutants reduced by 16.46 %, 27.88 %, 25.03 %, and 57.9 %, respectively, compared with wild-type strain inoculated, which indicated that biogenic electron produced by anaerobic respiratory of S. oneidensis MR-1 acted as a hole scavenger and maintained the anaerobic photoexcitation of CdS in BPRDS. Photoexcitation was essential for the BPRDS. This work may provide a new strategy for anaerobic remediation of organic contaminants and be beneficial for the better understanding about anaerobic photodegradation mechanism.

Functional porous carbon (PC) derived from bio-friendly shaddock peel has been firstly explored as catalyst for vanadium redox flow battery (VRB). The prepared PC is micro-mesoporous with high BET surface area of 882.7 m2 g−1, has some surface oxygen-containing functional groups, and is doped with N and P heteroatoms. These three factors greatly favor the electrochemical reactions of VO2+/ VO 2 + on the PC modified glass carbon (PC-GC). Compared with the naked GC and graphite modified GC, the PC-GC presents a lower peak separation (66 mV), higher anodic current density (17.1 mA cm−2) and cathodic current density (15.0 mA cm−2). The VRB using PC modified graphite felt (GF) as positive electrode demonstrates an enhanced voltage efficiency of 82.7% at the current density of 60 mA cm−2, and a better rate performance than that from the virginal GF.

Previous studies show that several pathways are involved in sanguinarine-induced apoptotic cell death, including AKT downregulation, inhibition of NF-kB activation, mediation of ROS production, downregulation of anti-apoptosis proteins XIAP and cIAP-1, upregulation of BAX, and downregulation of BCL2. In this study, we found out that the quenching of ROS generation by N-acetyl-l-cysteine (NAC), a scavenger of ROS, reversed sanguinarine-induced apoptosis effects, also we found out that sanguinarine-induced rat hepatic stellate T6 cells (HSC-T6 cells) apoptosis was correlated with the generation of increased ROS, which was followed by the activation of caspase-8 (-3, -6, and -9), and the decreasing in the miltochondrial membrane potential (MMP) and the down-regulation of anti-apoptotic protein Bcl-2. It is not clear whether BCL2's downregulation relates to its promoter methylation and miR-15a/16-1 expression which can bind to BCL2 3'-UTR (un-translation reagon). We showed that sanguinarine-induced down regulation of BCL2 was associated with the increased methylation rate of BCL2 promotor district and the increased expression of miR-15a/16-1. HSC-T6 cells treatment with 5-Aza-2'-deoxycytidine (5'-Aza-CdR) impeded sanguinarine-induced BCL2 promotor district methylation and recovered BCL2's expression. Over expression of BCL2 using pEGFP-N1 vector decreased sanguinarine-induced HSC-T6 cells apoptotic death significantly but not completely. These observations clearly showed that BCL2 down regulation was associated with its promoter methylation and miR-15a/16-1 upregulation in sanguinarine-induced Rat HSC-T6 cells.

Although sanguinarine (SANG) can be transformed to dihydrosanguinarine (DHSA) in human and animals, the enzyme involved in the imine bond reduction of SANG is still unknown. In this study, we found that rat NAD(P)H:quinone oxidoreductase 1 expressed by prokaryotic system can transform SANG to DHSA in an NADPH dependent manner. We also found out that there was more DHSA in rAAV-NQO1 infected than rAAV-CYP1A1 and rAAV-control infected BRL cells. SANG decreased rat BRL cell proliferation and augmented cell apoptosis in a time and dose dependent manner. However, the influence of DHSA to BRL cells is not significant difference than SANG. SANG-induced apoptosis was correlated with the up-regulation of Bax/Bcl2 ratio and the down-regulation of Bcl2. SANG can also dose dependently down regulate NQO1 expression, but CYP1A1 expression was a little up regulated. Since CYP1A1 involving in SANG oxidative reactions and NQO1 involving in the transform of SANG to DHSA, we hypothesized that up regulation of NQO1 could reduce SANG cytotoxicity and up regulation of CYP1A1 could increase SANG cytotoxitity. Our further study showed that recombinant adeno-associated virus (rAAV) mediated overexpression of NQO1 significantly increased cell proliferation and decreased Bax/Bcl2 ratio, apoptosis, and cytotoxicity, whereas rAAV mediated CYP1A1 overexpression had opposite effects. These data illustrated that NQO1 involved in the imine bond reduction of sanguinarine and this was a less toxic metabolizing pathway than CYP1A1-metabolizing pathway.

The multicomponent pharmacokinetic study of herbal medicine is a great challenge due to the low plasma concentrations, large range of concentration scales, lack of authentic standards and uncertain interactions of the components. The aim of this work was to explore the in vivo pharmacokinetics of herbal medicine independently of authentic standards using an integrated analytical strategy. First, ion pairs of multiple components were tuned and selected, and then major parameters were optimized for derivative multiple reaction monitoring (DeMRM) by LC-MS/MS, which was combined with characterization of the chemical profiles of the herbal medicine by LC-QqTOF/MS. Second, different concentrations of herbal extracts were employed instead of authentic standards to construct calibration curves for the semiquantitative determination of multiple components in plasma. Taking Gelsemium elegans as an example, in addition to the fully validated and sufficient methodological results, a total of 27 alkaloid components, major bioactive constituents of Gelsemium elegans, were simultaneously monitored in pig plasma. The concentration-time profiles and pharmacokinetic properties of these 27 components were characterized. The absolute quantification of three components was compared with the results obtained using authentic standards, and the method showed very similar analytical characteristics, such as linearity, precision, accuracy, and the values of the pharmacokinetic parameters Tmax, Vd, Cl and MRT. This analytical strategy was found to be capable of assessing herbal pharmacokinetics independently of specific authentic compounds for each component. This study was the first attempt to systematically reveal the in vivo pharmacokinetics of Gelsemium elegans. This strategy and methodology will find widespread use in the quantitative pharmacokinetic analysis of multiple components independently of standards for herbal medicine, among other applications.

Five trichothecenes, T-2 toxin, HT-2 toxin, deoxynivalenol (DON), 3-acetyl-DON (3-AcDON) and nivalenol (NIV), major class of mycotoxins produced by Fusarium , were investigated by electrospray hybrid ion trap/time-of-flight mass spectrometry (IT–TOF-MS). Fragmentation mechanisms are proposed based on the MS 2 and MS 3 experiments and accurate mass measurements. The sodium adduct ions [M+Na] + of type-A trichothecenes, such as T-2 toxin and HT-2 toxin, were observed in the MS spectra. However, the [M−H] − ions of type-B trichothecenes, such as NIV, and 3-AcDON, were observed in the MS spectra. Eliminations of isovaleryloxy group and acetic acid were the common fragmentation pathways of T-2 toxin and HT-2 toxin. However, the cleavage of epoxy was the common fragmentation pathways of DON, 3-AcDON and NIV. The other fragmentation pathways were found to be dependent on the substitutent group. The data reported here may help to identify analogues of the trichothecenes that are commonly co-produced by Fusarium in cultures or naturally contaminated samples.

In this study, the stress degradation of olaquindox under conditions of hydrolysis (neutral, acidic and basic), oxidation and photolytic stress was investigated. In order to characterize each degradation product, we developed a rapid, sensitive and reliable high-performance liquid chromatography combined with hybrid ion trap/time-of-flight mass spectrometry (LC/MS-IT-TOF) method. The degradation products formed under different forced conditions were separated using an ODS-C18 column with gradient elution. Multiple scans of degradation products in MS and MS/MS modes and accurate mass measurements were performed through data-dependent acquisition. The structural elucidations of degradation products were performed by comparing the changes in the accurate molecular masses and fragment ions generated from precursor ions with those of parent drug. The present results showed that maximum degradation was observed in hydrolysis, especially in the acidic condition. The drug was also degraded significantly under photolytic conditions. A total of 12 degradation products of olaquindox were detected and characterized using the developed method. The main degradation product was formed by the complete cleavage of side chain to form 3-methyl-2-hydroxylquinoxaline-4-oxide. A degradation pathway of olaquindox was also tentatively proposed for the first time based on these characterized structures.