Bergenin Alleviates Ulcerative Colitis By Decreasing Gut Commensal Bacteroides vulgatus-Mediated Elevated Branched-Chain Amino Acids.

Ulcerative colitis is closely associated with the dysregulation of gut microbiota. There is growing evidence that natural products may improve ulcerative colitis by regulating the gut microbiota. In this research, we demonstrated that bergenin, a naturally occurring isocoumarin, significantly ameliorates colitis symptoms in dextran sulfate sodium (DSS)-induced mice. Transcriptomic analysis and Caco-2 cell assays revealed that bergenin could ameliorate ulcerative colitis by inhibiting TLR4 and regulating NF-κB and mTOR phosphorylation. 16S rRNA sequencing and metabolomics analyses revealed that bergenin could improve gut microbiota dysbiosis by decreasing branched-chain amino acid (BCAA) levels. BCAA intervention mediated the mTOR/p70S6K signaling pathway to exacerbate the symptoms of ulcerative colitis in mice. Notably, bergenin greatly decreased the symbiotic bacteria Bacteroides vulgatus (B. vulgatus), and the gavage of B. vulgatus increased BCAA concentrations and aggravated the symptoms of ulcerative colitis in mice. Our findings suggest that gut microbiota-mediated BCAA metabolism plays a vital role in the protective effect of bergenin on ulcerative colitis, providing novel insights for ulcerative colitis prevention through manipulation of the gut microbiota.

Sinomenine ameliorates rheumatoid arthritis by modulating tryptophan metabolism and activating aryl hydrocarbon receptor via gut microbiota regulation.

Gut microbiota dysbiosis is associated with the development of rheumatoid arthritis (RA). Sinomenine (SIN) is an effective immunosuppressive and anti-inflammatory drug used for treating RA, but how SIN regulates gut microbiota to alleviate RA remains underexplored. To identify the critical gut microbial species and microbial metabolites associated with the RA-protective effects of SIN, the microbiota-dependent anti-RA effects of SIN were assessed by 16S rRNA gene sequencing, antibiotic treatment, and fecal microbiota transplantation. Metabolomics analysis, transcriptional analysis, and targeted bacteria/metabolites gavage were conducted to explore how SIN regulates gut microbiota to reduce the severity of RA. SIN could restore intestinal microbial balance by mainly modulating the abundance of Lactobacillus, and significantly relieve collagen-induced arthritis (CIA) symptoms in a gut microbiota-dependent manner. SIN significantly elevated microbial tryptophan metabolites indole-3-acrylic acid (IA), indole-3-propionic acid (IPA), and indole-3-acetic acid (IAA). Tryptophan metabolites supplementation could activate aryl hydrocarbon receptor (AhR) and regulate Th17/Treg balance in CIA rats. Intriguingly, SIN relieved the arthritis symptoms involving the enrichment of two beneficial anti-CIA Lactobacillus species, L. paracasei and L. casei by mono-colonization. The promising therapeutic function of SIN was mostly attributed to the activation of AhR by explicitly targeting the Lactobacillus and microbial tryptophan metabolites. The intestinal bacterium L. paracasei and L. casei may be used to reduce the severity of CIA.

Nobiletin Ameliorates Nonalcoholic Fatty Liver Disease by Regulating Gut Microbiota and Myristoleic Acid Metabolism.

Disturbance of the gut microbiota plays a critical role in the development of nonalcoholic fatty liver disease (NAFLD). Increasing evidence supports that natural products may serve as prebiotics to regulate the gut microbiota in the treatment of NAFLD. In the present study, the effect of nobiletin, a naturally occurring polymethoxyflavone, on NAFLD was evaluated, and metabolomics, 16S rRNA gene sequencing, and transcriptomics analysis were performed to determine the underlying mechanism of nobiletin, and the key bacteria and metabolites screened were confirmed by in vivo experiment. Nobiletin treatment could significantly reduce lipid accumulation in high-fat/high-sucrose diet-fed mice. 16S rRNA analysis demonstrated that nobiletin could reverse the dysbiosis of gut microbiota in NAFLD mice and nobiletin could regulate myristoleic acid metabolism, as revealed by untargeted metabolomics analysis. Treatment with the bacteria Allobaculum stercoricanis, Lactobacillus casei, or the metabolite myristoleic acid displayed a protective effect on liver lipid accumulation under metabolic stress. These results indicated that nobiletin might target gut microbiota and myristoleic acid metabolism to ameliorate NAFLD.

Authentication of Platycladus Orientalis Leaves and Its Five Adulterants by Combination of Morphology and Microscopic Characteristics, TLC, and HPLC Analysis.

BACKGROUND: Platycladus orientalis leaves (POL), as the source of the traditional Chinese medicine (TCM) Platycladi Cacumen, has frequently been found to be misused with five adulterants including Chamaecyparis obtusa leaves (COL), Cupressus funebris leaves (CFL), Juniperus virginiana leaves (JVL), Sabina chinensis leaves (SCL), and Juniperus formosana leaves (JFL). OBJECTIVE: The purpose of this study was to distinguish POL (fresh leaves) from its five adulterants (fresh leaves). METHODS: The micromorphological features in terms of transection and microscopic characteristics of POL and adulterants were captured and compared using the an microscope. Both HPLC and TLC methods for the simultaneous determination of six bioactive flavonoids (myricitrin, isoquercitrin, quercitrin, amentoflavone, afzelin, and hinokiflavone) have been developed. RESULTS: There were significant differences in microscopic features of transverse section and powders. The TLC results suggested that the spots of myricitrin in POL were more obvious than those in the five adulterants. The contents of myricitrin and quercitrin, or the total content of flavonoids in POL, determined by HPLC, were significantly higher than those in the adulterants. CONCLUSION: POL was successfully distinguished from its five adulterants by the comparison of morphology, microscopic characteristics, and chemical profiles. HIGHLIGHTS: This research provides a comprehensive morphology, microscopic identification, TLC, and HPLC analysis for authenticating POL and its five adulterants.

Construction of coaxial liquid centrifugal platform for the extraction of active ingredients from natural products.

In the classical natural product extraction and separation process, it is tedious and requires large amounts of reagents and time. In this study, an efficient coaxial liquid centrifugal oil-water-oil triple-liquid-phase system with a simple structure and convenient operation was successfully constructed and used to extract flavonoids from Platycladi Cacumen. The results showed that the coaxial liquid centrifugal platform constructed in this study had good stability and 6 ml was the minimum volume of the middle phase for 1000 rpm to stabilize the system. Besides, it was easy to repeat the operation: the relative standard deviations of the extraction yields of flavonoids and sugar in six parallel operations were all less than 10%. Moreover, it was only one-tenth of the time required for this method as traditional liquid-liquid extraction while reducing the use of volatile organic reagents. Finally, the new method was more selective than the traditional method for the extraction of flavonoids. Therefore, this study provides a possibility for the coaxial liquid centrifugal platform to be used in multi-liquid phase systems to achieve the simultaneous extraction of different parts of natural products by different liquid phases. It is expected to provide a reliable reference for further expansion of small-scale experimental operations to industrial production.

Design, synthesis and biological evaluation of novel 9-N-substituted-13-alkylberberine derivatives from Chinese medicine as anti-hepatocellular carcinoma agents.

A series of novel 9-N-substituted-13-alkylberberine derivatives from Chinese medicine were designed and synthesized with improved anti-hepatocellular carcinoma (HCC) activities. The optimal compound 4d showed strong activities against HepG2, Sk-Hep-1, Huh-7 and Hep3B cells with IC50 values of 0.58-1.15 µM, which were superior to positive reference cisplatin. Interestingly, 4d exhibited over 40-fold more potent activity against cisplatin-resistant HepG2/DPP cells while showing lower cytotoxicity in normal LX-2 cells. The mechanism studies revealed 4d greatly stabilized G-quadruplex DNA leading to intracellular c-MYC expression downregulation, blocked G2/M-phase cell cycle by affecting related p-cdc25c, cdc2 and cyclin B1 expressions, and induced apoptosis by a ROS-promoted PI3K/Akt-mitochondrial pathway. Furthermore, 4d possessed good pharmacokinetic properties and significantly inhibited the tumor growth in the H22 liver cancer xenograft mouse model without obvious toxicity. Altogether, the remarkably biological profiles of 4d both in vitro and in vivo would make it a promising candidate for HCC therapy.

Evolving interplay between natural products and gut microbiota.

Growing evidence suggests gut microbiota status affects human health, and microbiota imbalance will induce multiple disorders. Natural products are gaining increasing attention for their therapeutical effects and less side effects. The emerging studies support that the activities of many natural products are dependent on gut microbiota, meanwhile gut microbiota is modulated by natural products. In this review, we summarized the interplay between the gut microbiota and host disease, and the emerging molecular mechanisms of the interaction between natural products and gut microbiota. Focusing on gut microbiota metabolite of various natural products, and the effects of natural products on gut microbiota, we summarized the biotransformation pathways of natural products, and discussed the effect of natural products on the composition modulation of gut microbiota, protection of gut mucosal barrier and modulation of the gut microbiota metabolites. Dissecting the interplay between gut microbiota and natural products will help elucidate the therapeutic mechanisms of natural products.

Discovery of potential hypoglycemic metabolites in Cassiae Semen by coupling UHPLC-QTOF-MS/MS combined plant metabolomics and spectrum-effect relationship analyses.

Cassiae Semen (CS) is consumed as fried tea or medicinal food in Asian areas. Its two commercial forms, namely raw and fried CS, exert different clinical applications, in which fried CS is commonly applied as a functional tea for losing weight. To prevent confusion in the use of the two forms of CS, a comprehensive strategy by combining plant metabolomics and spectrum-effect relationship analyses was developed for the fast and efficient discrimination of raw and fried CS, and further for the discovery of the potential hypoglycemic metabolites of CS to control its quality. First, the plant metabolic profiling of raw and processed samples was performed by UHPLC-QTOF-MS/MS. A total of 1111 differential metabolites were found to well distinguish the raw and fried CS after analyzing by MPP software. Subsequently, α-glucosidase inhibition of raw and fried CS was investigated. As a result, fried CS demonstrated much stronger α-glucosidase inhibition activity than the raw sample. By analyzing the spectrum-effect relationship with GRA, BCA, and PLSR, 14 potential hypoglycemic-related compounds were discovered. As anticipated, they were also found as the differential metabolites of the raw and fried samples with a potential hypoglycemic effect, which might be beneficial for the quality control of CS tea. Additionally, molecular docking analysis was conducted to reveal the underlying inhibition mechanisms of the four most critical constituents, including physcion, chrysoobtusin, aurantio-obtusin, and obtusifolin. This study provides a powerful tool for the discrimination of processed samples and fast screening of the active constituents in complex natural products on a high-throughput basis.

New 4',5'-methylenedioxyflavone derivatives from the whole plant of sarcandra glabra.

Two new natural products named 5,7-dihydroxy-3,3',6,8-tetramethoxy-4',5'-methylenedioxyflavone (1) and 3,3',5,7-tetramethoxy-4',5'-methylenedioxyflavone (2), along with thirteen known compounds, ß-sitosterol (3), desmethoxyyangonin (4), hexadecane (5), 3,9-bis(2,4-di-tert-butylphenoxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane 3,9-dioxide (6), 2'6'-dihydroxy-4'-methoxydihydrochalcone (7), cardamonin (8), 3,3',5,6,7,8-hexamethoxy-4',5'-methylenedioxyflavone (9), isofraxidin (10), aniba dimer A (11), 3,3',4',5,5',8-hexamethoxy-6,7-methylenedioxyflavone (12), quercetin (13), quercitrin (14) and isoquercitrin (15) were isolated from Sarcandra glabra (Thunb.) Nakai by various chromatographic methods. Compounds 1, 2, 4, 6, 11, and 12 were isolated from S. glabra for the first time. Their chemical structures were identified through the analysis of NMR and HR-MS spectra. The anti-inflammatory and cytotoxic activities of compounds 1-15 were evaluated in cell assays. The results indicated that compounds 1, 7, 8, 10, 14, and 15 significantly inhibited the NO production in LPS-induced RAW 264.7 murine macrophage cells. Moreover, compounds 1, 3, 4, 7, 8, 9, 10 and 12 exhibited a cytotoxic effect on the human HepG2 cell line.

The antihyperlipidemic equivalent combinatorial components from peel of Citrus reticulata 'Chachi'.

Since the combinatorial components responsible for the antihyperlipidemic activity of Citrus reticulata 'Chachi' (CRC) peels remains unclear, we herein developed a bioactive equivalence oriented feedback screening method to discover the bioactive equivalent combinatorial components (BECCs) from CRC peels. Using palmitic acid (PA)-stimulated hepatocyte model, a combination of 5 polymethoxyflavones (PMFs) including tangeretin, sinensetin, nobiletin, 5,7,8,4'-tetramethoxyflavone and 3,5,6,7,8,3',4'-heptamethoxyflavone was identified to be responsible for the antihyperlipidemic effect of CRC peels. Via evaluation of combination effect by combination index (CI), these 5 PMFs were found to take effect via a synergistic mode. Our data indicated that the antihyperlipidemic mechanism of PMF combination was associated with the inhibition of fatty acid and cholesterol synthesis, and inflammation. Also, the PMF combination exhibited robust antihyperlipidemic effects in HFD-fed rats in vivo. Our study offers evidence-based data to uncover the pharmacological effect of CRC peels.

Baicalin attenuate diet-induced metabolic syndrome by improving abnormal metabolism and gut microbiota.

In this work, we examined whether baicalin (BC), a bioactive flavonoid in Scutellaria baicalensis Georgi, can reduce high-fat diet (HFD)-induced metabolic syndrome (MetS) in mice. The UPLC-QTOF/MS was used for metabolome profiles analysis, and an analysis of bacterial 16S rDNA in feces was used to examine the effects of BC on gut microbiota composition. Our results showed that BC (400 mg/kg) could reduce the body weight gain, decrease hepatic fat accumulation and abnormal blood lipids, and increase insulin sensitivity after 8 weeks of treatment. BC could reverse the alteration of 7 metabolites induced by HFD and the metabolic pathways responsive to BC intervention including citrate cycle, alanine, aspartate and glutamate metabolism, glycerophospholipid metabolism, and aminoacyl-tRNA biosynthesis. 16S rDNA analysis demonstrated that BC altered the composition and function of gut microbiota in MetS mice. Notably, we found that the change in succinic acid was negatively associated with the changes in Bacteroides and Sutterella, and positively associated with the change in Mucispirillum. Moreover, we confirmed that succinic acid displayed a metabolic protective effect on MetS mice. The antibiotic treatment verified that BC exerts metabolic protection through gut microbiota. Our findings suggested BC may be a potential therapeutic drug to ameliorate diet induced MetS and gut microbiome may be a novel mechanistic target of BC for treatment of MetS.

Screening of hypoglycemic components in Platycladi Cacumen by phytochemical investigation, spectrum-effect relationship, and chemometric methods.

In this work, the hypoglycemic components in Platycladi Cacumen, an essential traditional Chinese medicine, were evaluated by combining phytochemical investigation, spectrum-effect relationship analysis, and chemometric methods. The phytochemical studies on Platycladi Cacumen extract lead to the isolation of 21 potential bioactive compounds. The chromatographic fingerprints of Platycladi Cacumen samples were established by high-performance liquid chromatography. The hypoglycemic effects of Platycladi Cacumen samples were further evaluated by inhibition of α-glucosidase and detected by the high-performance liquid chromatography method. The spectrum-effect relationship study by bivariate correlations analysis and orthogonal partial least squares regression revealed that myricitrin (P9), quercitrin (P13), afzelin (P18), and amentoflavone (P24) were more relevant to the α-glucosidase inhibitory activity. The results of α-glucosidase inhibitory activity of 21 isolated compounds and molecular docking studies also indicated these flavonoids had potent α-glucosidase inhibitory activity. Collectively, the present study established the spectrum-effect relationship mode of Platycladi Cacumen and discovered the major hypoglycemic components, which provides a feasible method for screening bioactive components.

Spectrum-Effect Relationships Between High-Performance Liquid Chromatography Fingerprints and Hepatoprotective Activities of Cuscutae Semen.

BACKGROUND: Cuscutae Semen (CS) is a commonly used hepatoprotective traditional Chinese medicine, but the chemical components responsible for its hepatoprotective activity are unclear. OBJECTIVE: The purpose of this study was to evaluate the spectrum-effect relationships between HPLC fingerprints and hepatoprotective effects of CS, and to identify its bioactive components. METHODS: Phytochemical isolation of CS extracts was first carried out and 14 potential bioactive compounds were obtained. Chemical fingerprinting was performed on 27 batches of CS from different sources by HPLC, and further analyzed by similarity analysis (SA) and hierarchical clustering analysis (HCA). Pharmacodynamic testing was performed in a CCl4-induced, acute liver injury cell model to assess the hepatoprotective activity of CS by measuring the cell viability and levels of alanine transaminase (ALT) and aspartate aminotransferase (AST). Bivariate correlations analysis (BCA) and orthogonal projections to latent structures (OPLS) were used to analyze the spectrum-effect relationships of CS. RESULTS: The results showed that the chemical fingerprints of CS were closely correlated with its hepatoprotective activity. Peaks 1, 10, 18, 19, 21, 22, and 24 might be potential hepatoprotective compounds in CS, and the validation experiments of isolated compounds indicated that chlorogenic acid (P10), hyperoside (P21), isoquercitrin (P22), and astragalin (P24) were the main hepatoprotective components. CONCLUSION: By combining chemical fingerprints with hepatoprotective evaluation, the present study provides important guidance for QC and clinical use of CS. HIGHLIGHTS: (1) Ten potential bioactive compounds were isolated from CS; (2) The spectrum-effect relationship of CS was molded by HPLC and analysed by OPLS and BCA. (3) Four compounds including chlorogenic acid were the main hepatoprotective components.

Identification of antidiabetic components in Uncariae Rammulus Cum Uncis based on phytochemical isolation and spectrum-effect relationship analysis.

OBJECTIVES: Uncariae Rammulus Cum Uncis (URCU) is a commonly used herbal medicine to treat diabetes. This work is aimed to discover and identify the antidiabetic components from URCU extract. METHODS: Column chromatography and recrystallisation were used to separate individual compounds from URCU extract, and the obtained individual compounds were used for determination of α-glucosidase inhibitory activity. Molecular docking was applied to predict the molecular interactions. High-performance liquid chromatography (HPLC) was used for fingerprint analysis of 12 batches of URCU. HPLC fingerprints were assessed by the similarity analysis (SA) and hierarchical clustering analysis (HCA). The spectrum-effect relationship analysis of URCU was assessed by orthogonal partial least squares (OPLS) and bivariate correlation analysis (BCA). RESULTS: A total of 10 potential bioactive compounds were isolated and six of them showed potent α-glucosidase inhibitory activity (IC50 = 4.21-166.10 µM). The molecular docking results revealed that the binding energy was consistent with the results of α-glucosidase inhibition activity analysis (-8.55 to -4.84 kcal/mol). The ethanol extracts of the 12 batches of URCU showed inhibitory effect on α-glucosidase in a dose-dependent manner, and the IC50 values ranged from 0.94 µg/mL to 12.57 µg/mL. The spectrum-effect relationship analysis results indicated that 13 peaks might be potential antidiabetic compounds in URCU, including 18 (hyperoside) and 19 (rutin). CONCLUSION: A comprehensive connection between URCU chemical components and α-glucosidase inhibitory activity was established for the first time by using a spectrum-effect relationship model, which might be applicable to the quality control of URCU.

A simple and sensitive preconcentration strategy by coupling salting-out assisted liquid-liquid extraction with online three-step stacking for the determination of potent anti-tumour compound vinblastine and its precursor in biological samples by capillary electrophoresis.

A sensitive capillary electrophoresis strategy was developed by combining salting-out assisted liquid-liquid extraction and online three-step stacking to detect trace quantities of antitumour indole alkaloids in complex biological samples. The proposed strategy fully exploits these two technologies such that extraction, online stacking and separation are combined in a fast and efficient manner. First, salting-out assisted liquid-liquid extraction was used to extract three indole alkaloids (vinblastine sulfate, catharanthine sulfate and vindoline) from complex biomasses. An appropriate volume of acetonitrile (ACN) was mixed with a faecal aqueous solution to precipitate proteins. The mixed solution was vortexed, followed by the addition of ammonium sulfate ((NH4)2SO4) to induce two-phase separation. Alkaloids were effectively extracted into the organic phase, which was then subjected to capillary electrophoresis (CE) analysis. The sensitivity of capillary electrophoresis was effectively improved by online three-step stacking. Good linearity of the calibration curve for each indole alkaloid was obtained in the concentration range of 0.1-1 µg/mL. Under optimal conditions, the sensitivity of ordinary injection was increased by up to 2366-fold, confirming the applicability of the proposed strategy for the sensitive determination of trace indole alkaloids in complex biological samples.

Anti-obesity natural products and gut microbiota.

The link between gut microbiota and obesity or other metabolic syndromes is growing increasingly clear. Natural products are appreciated for their beneficial health effects in humans. Increasing investigations demonstrated that the anti-obesity bioactivities of many natural products are gut microbiota dependent. In this review, we summarized the current knowledge on anti-obesity natural products acting through gut microbiota according to their chemical structures and signaling metabolites. Manipulation of the gut microbiota by natural products may serve as a potential therapeutic strategy to prevent obesity.

Discovery of a potent FKBP38 agonist that ameliorates HFD-induced hyperlipidemia via mTOR/P70S6K/SREBPs pathway.

The mammalian target of rapamycin (mTOR)-sterol regulatory element-binding proteins (SREBPs) signaling promotes lipogenesis. However, mTOR inhibitors also displayed a significant side effect of hyperlipidemia. Thus, it is essential to develop mTOR-specific inhibitors to inhibit lipogenesis. Here, we screened the endogenous inhibitors of mTOR, and identified that FKBP38 as a vital regulator of lipid metabolism. FKBP38 decreased the lipid content in vitro and in vivo via suppression of the mTOR/P70S6K/SREBPs pathway. 3,5,6,7,8,3',4'-Heptamethoxyflavone (HMF), a citrus flavonoid, was found to target FKBP38 to suppress the mTOR/P70S6K/SREBPs pathway, reduce lipid level, and potently ameliorate hyperlipidemia and insulin resistance in high fat diet (HFD)-fed mice. Our findings suggest that pharmacological intervention by targeting FKBP38 to suppress mTOR/P70S6K/SREBPs pathway is a potential therapeutic strategy for hyperlipidemia, and HMF could be a leading compound for development of anti-hyperlipidemia drugs.

Purification, Structural Characterization and Immunomodulatory Effects of Polysaccharides from Amomumvillosum Lour. on RAW 264.7 Macrophages.

Amomum Villosum Lour. (A. villosum) is a folk medicine that has been used for more than 1300 years. However, study of the polysaccharides of A. villosum is seriously neglected. The objectives of this study are to explore the structural characteristics of polysaccharides from A. villosum (AVPs) and their effects on immune cells. In this study, the acidic polysaccharides (AVPG-1 and AVPG-2) were isolated from AVPs and purified via anion exchange and gel filtration chromatography. The structural characteristics of the polysaccharides were characterized by methylation, HPSEC-MALLS-RID, HPLC, FT-IR, SEM, GC-MS and NMR techniques. AVPG-1 with a molecular weight of 514 kDa had the backbone of → 4)-α-d-Glcp-(1 → 3,4)-ß-d-Glcp-(1 → 4)-α-d-Glcp-(1 →. AVPG-2 with a higher molecular weight (14800 kDa) comprised a backbone of → 4)-α-d-Glcp-(1 → 3,6)-ß-d-Galp-(1 → 4)-α-d-Glcp-(1 →. RAW 264.7 cells were used to investigate the potential effect of AVPG-1 and AVPG-2 on macrophages, and lipopolysaccharide (LPS) was used as a positive control. The results from bioassays showed that AVPG-2 exhibited stronger immunomodulatory activity than AVPG-1. AVPG-2 significantly induced nitric oxide (NO) production as well as the release of interleukin (IL)-6 and tumor necrosis factor alpha (TNF-α), and upregulated phagocytic capacities of RAW 264.7 cells. Real-time PCR analysis revealed that AVPG-2 was able to turn the polarization of macrophages to the M1 direction. These results suggested that AVPs could be explored as potential immunomodulatory agents of the functional foods or complementary medicine.

Online discovery of the molecular mechanism for directionally detoxification of Fuzi using real-time extractive electrospray ionization mass spectrometry.

ETHNOPHARMACOLOGICAL RELEVANCE: Aconitum carmichaelii Debeaux, a famous traditional medicinal herb for collapse, rheumatic fever, and painful joints, always raises global concerns about its fatal toxicity from toxic alkaloids when improperly processed. Therefore, it is urgent to clarify the internal molecular mechanism of processing detoxification on Aconitum and develop simple and reliable approaches for clinical application, which is also of great significance to the rational medicinal use of Aconitum. AIM OF THE STUDY: The study aimed at developing a complete molecular mechanism exploration strategy in complex medicinal herb decocting system, clarifying the internal molecular mechanism of processing detoxification on Aconitum, and exploring valid approaches for detoxification. MATERIALS AND METHODS: Aconiti Lateralis Radix Praeparata (Fuzi) was selected as the model for exploring the complex Aconitum detoxification mechanism using an advanced online real-time platform based on extractive electrospray ionization mass spectrometry. The methods realized the sensitive capture of dynamic trace intermediates, accurate qualitative and quantitative analysis, and real-time and long-term monitoring of multi-components with satisfactory accuracy and resistance to complex matrices. RESULTS: Components in the complex Aconitum decocting system were real-timely characterized and fat meat was discovered and verified to directionally detoxify Aconitum while reserving the therapy effect. More importantly, the dynamic detoxification mechanism in the chemically complex Aconitum decoction was molecularly profiled. A novel reaction pathway based on nucleophilic substitution reaction mechanism was proposed. As confirmed by the theoretic calculations at DFT B3LYP/6-31G (d) levels, fatty acids (e.g., palmitic acid) acted as a green, cheap, and high-performance catalyst and promote the decomposition of toxic diester alkaloids to non-toxic and active benzoyl-monoester alkaloids through the discovered mechanism. CONCLUSION: The study exposed a novel detoxification molecular mechanism of Aconitum and provided an effective method for the safe use of Aconitum, which could effectively guide the development of traditional processing technology and compatibility regulation of the toxic herb and had great value to the modernization and standardization development of traditional medicine.

In vitro human intestinal microbiota biotransformation of nobiletin using liquid chromatography-mass spectrometry analysis and background subtraction strategy.

In this study, the in vitro biotransformation of nobiletin by human intestinal microbiota, which is a bioactive polymethoxyflavone widely presented in Citrus plants, has been investigated via utilizing an anaerobic incubation protocol. The incubation samples were detected using high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry. A background subtraction strategy incorporated in Microsoft Office was employed to eliminate the interferences in medium and feces. The parent and three metabolites sinensetin, 5-hydroxy-6,7,3',4'-tetramethoxyflavone, and 5-demethylnobiletin were detected and identified based on the characteristics of their protonated molecules. The proposed metabolic pathway revealed that nobiletin went through phase I metabolism including demethylation and demethoxylation in human intestinal microbiota. The characterization of nobiletin metabolic profile transformed by human intestinal bacteria would be helpful for understanding its efficacy and action mechanism.