In vitro biotransformation of red ginseng extract by human intestinal microflora: Metabolites identification and metabolic profile elucidation using LC–Q-TOF/MS

Pharmacological effects of ginseng and ginsenosides on intestinal inflammation and the immune system

Intestinal inflammatory imbalance and immune dysfunction may lead to a spectrum of intestinal diseases, such as inflammatory bowel disease (IBD) and gastrointestinal tumors. As the king of herbs, ginseng has exerted a wide range of pharmacological effects in various diseases. Especially, it has been shown that ginseng and ginsenosides have strong immunomodulatory and anti-inflammatory abilities in intestinal system. In this review, we summarized how ginseng and various extracts influence intestinal inflammation and immune function, including regulating the immune balance, modulating the expression of inflammatory mediators and cytokines, promoting intestinal mucosal wound healing, preventing colitis-associated colorectal cancer, recovering gut microbiota and metabolism imbalance, alleviating antibiotic-induced diarrhea, and relieving the symptoms of irritable bowel syndrome. In addition, the specific experimental methods and key control mechanisms are also briefly described.

Therapeutic effect of notoginseng saponins before and after fermentation on blood deficiency rats

Notoginseng saponins (NS) are the active ingredients in Panax notoginseng (Burk.) F.H. Chen (PN). NS can be transformed depending on how the extract is processed. Fermentation has been shown to produce secondary ginsenosides with increased bioavailability. However, the therapeutic effect of fermented NS (FNS) requires further study. The present study compared the compositions and activities of FNS and NS in blood deficiency rats, which resembles the symptoms of anemia in modern medicine, induced by acetylphenylhydrazine and cyclophosphamide. A total of 32 rats were randomly divided into control, model, FNS and NS groups. A blood deficiency model was established and then treatment was orally administered for 21 days. The results of component analysis indicated that some saponins transformed during the fermentation process resulting in a decrease of notoginsenoside R1, and ginsenosides Rg1, Rb1 and Re, and an increase in ginsenosides Rd, Rh2, compound K, protopanaxadiol and protopanaxatriol. The animal results showed that both FNS and NS increased the number of white blood cells (WBCs), red blood cells, hemoglobin, platelets and reticulocytes, and the levels of granulocyte-macrophage colony-stimulating factor (GM-CSF), erythropoietin (EPO) and thrombopoietin (TPO), decreased the G0/G1 phase and increased G2/M phase, and decreased the apoptosis rate of bone marrow (BM) cells, which suggested a contribution to the recovery of hematopoietic function of the BM cells. FNS and NS increased the protein expression levels of the cytokines IL-4, IL-10, IL-12, IL-13, TGF-β, IL-6, IFN-γ and TNF-α, and the mRNA expression levels of transcription factors GATA binding protein 3 and T-box expressed in T cell (T-bet). FNS and NS treatment also increased the number of CD4+ T cells, and decreased the enlargement of the rat spleen and thymus atrophy, which indicated a protective effect on the organs of the immune system. The results of the present study demonstrated that compared with NS, FNS showed an improved ability to increase the levels of WBCs, lymphocytes, GM-CSF, EPO, TPO, aspartate aminotransferase, IL-10, IL-12, IL-13 and TNF-α, and the mRNA expression levels of T-bet, and decrease alanine aminotransferase levels. The differences seen for FNS treatment could arise from their improved bioavailability compared with NS, due to the larger proportion of hydrophobic ginsenosides produced during fermentation.

Systematic analysis of the material basis and mechanism of total saponins of mountain cultivated ginseng against doxorubicin-induced cardiotoxicity based on integrating network pharmacology and in vivo substance profiling

INTRODUCTION

Doxorubicin-induced cardiotoxicity (DIC) is a serious obstacle to oncologic treatment. Mountain cultivated ginseng (MCG) exhibits stronger pharmacological effects than cultivated ginseng (CG) mainly due to the differences in ginsenosides. However, the material basis and the underlying mechanism of the protective effects of total saponins of MCG (TSMCG) against DIC are unclear.

OBJECTIVES

We aimed to elucidate the material basis and the pharmacodynamic effects of TSMCG on DIC as well as the underlying mechanisms.

METHODS

To comprehensively analyze the effective substances, the chemical components of TSMCG and their prototypes or metabolites in vivo were characterized through UHPLC/Q-TOF-MS. Then, an absorbed component-target-disease network was established to explore the mechanisms underlying the protective effects of TSMCG against DIC. H9c2 cells were employed for pharmacodynamic assays. The mechanism was verified by Western blot and molecular docking simulations.

RESULTS

A total of 56 main ginsenosides were identified in TSMCG, including 27 ginsenosides of PPD type, 15 ginsenosides of PPT type, two ginsenosides of OA types, and 12 ginsenosides of other types. Moreover, 55 ginsenoside prototypes or metabolites in vivo were tentatively characterized. Ginsenoside Ra1 , a differential compound between MCG and CG, could be metabolized by oxidation and deglycosylation. Network pharmacology showed that AKT1, p53, and STAT3 are core targets of 62 intersecting genes. Molecular docking results indicated that most of the ginsenosides have favorable affinity with these core targets. After doxorubicin exposure, TSMCG could increase cell viability and inhibit apoptosis in a dose-dependent manner.

CONCLUSION

Our work reveals a novel comprehensive strategy to study the material basis of the protective effects of TSMCG against DIC and the underlying mechanisms through integrating in vivo substance identification, metabolic profiling, network pharmacology, pharmacodynamic evaluation, and mechanism verification.

Discrepancy Study of the Chemical Constituents of Panax Ginseng from Different Growth Environments with UPLC-MS-Based Metabolomics Strategy

Panax ginseng (P. ginseng), the dried root and rhizome of P. ginseng C. A. Meyer, is widely used in many fields as dietary supplements and medicine. To characterize the chemical constituents in P. ginseng cultivated in different growth environments, a UPLC-TOF-MS method was established for qualitative analysis. Four hundred and eight ginsenosides, including 81 new compounds, were characterized in P. ginseng from different regions. Among the detected compounds, 361 ginsenosides were recognized in P. ginseng cultivated in the region of Monsoon Climate of Medium Latitudes, possessing the largest amount of ginsenosides in all samples. Furthermore, 41 ginsenosides in 12 batches of P. ginsengs were quantified with a UPLC-MRM-MS method, and P. ginsengs from different regions were distinguished via chemometric analysis. This study showed that the different environments have a greater influence on P. ginseng, which laid a foundation for further quality control of the herb.

A novel strategy integrating gas phase fractionation with staggered mass range and LC-MS/MS molecular network for comprehensive metabolites profiling of Gui Ling Ji in rats

Metabolite detection from complex biological samples faces challenges due to interference from endogenous substrates and the inherent limitation of multiple subsequent tandem scanning rates of instruments. Here, a new integrated approach based on gas-phase fractionation with a staggered mass range (sGPF) and a liquid chromatography-tandem mass spectrometry (LC-MS/MS) molecular network was developed to accelerate the data processing of the targeted and untargeted constituents absorbed in rats after oral administration of the traditional Chinese medicine (TCM) prescription Gui Ling Ji (GLJ). Compared with three conventional acquisition methods, sGPF at 3, 5, and 7 mass fractions could enhance MS/MS coverage with an increased MS/MS triggering rate of 29.4-206.2% over data-dependent acquisition (DDA), fast DDA and gas-phase fractionation. A mass range fraction setting of five optimized the performance. Based on the similar diagnostic fragment ions and characteristic neutral loss behaviors in the DDA-MS/MS spectrum, an initial molecular network of GLJ was created with the help of the global natural products social molecular networking (GNPS) platform. Furthermore, to remove the endogenous interference nodes, Cytoscape software was adopted to produce a clean and concise molecular network of prototype compounds and their corresponding metabolites. Using this strategy, a total of 210 compounds, including 59 prototype constituents and 151 metabolites, was unambiguously or tentatively identified in GLJ. This first systematic metabolic study of GLJ in vivo elucidated the potential pharmacodynamic basis of GLJ in clinical treatment. More importantly, this work can serve as a practical example and establish a guide for rapidly identifying TCM metabolites in biological matrices.

Metabolic profile and dynamic characteristic of rhubarb during the vitro biotransformation by human gut microbiota

Rhubarb is a popular food in the world with laxative effects and steamed pieces of rhubarb (SP) have been widely applied to treatment of constipation in China due to its safety and effectiveness. In the study, metabolism in vitro was conducted to study influence of gut microbiota between raw pieces of rhubarb (RP) and SP. The results showed obvious classifications in metabolic profile between RP and SP were revealed by chemometric analysis, and prompted gut microbiota affected metabolism of rhubarb. Furthermore, 16 characteristic components were identified to distinguish the differences in metabolism. Finally, quantitative analysis of 14 components were verified the regulation of gut microbiota on rhubarb and discovered concentration of components affected the rate of metabolism. The study indicated regulation by gut microbiota could be probably responsible for differences of laxative effects between RP and SP, providing new perspective for exploring mechanisms of effectiveness in clinical application for SP.

Global analysis of qualitative and quantitative metabolism of Notoginsenoside R1 in rat liver-brain-gut axis based on LC-IT-TOF/MS combing mMDF strategy

BACKGROUND

The metabolism study of active components for traditional Chinese medicine (TCM) in target organs is conducive to clarify the authentic active ingredients. Notoginsenoside R1 (NG-R1), one of the bioactive components of Panax notoginsenoside (PNS), is commonly acknowledged as the characteristic marker of PNS. However, the metabolism of NG-R1 in target organs has not been clarified yet due to the lack of robust technique and approach.

PURPOSE

The present study aimed to develop a reliable and efficient strategy and technology for revealing the qualitative and quantitative metabolism of active components of TCMs in target organs, and to clarify the biotransformation of NG-R1 in liver-brain-intestinal axis.

METHODS

The metabolic transformation of NG-R1 in the brain gut axis was investigated in the in vitro incubation system of fresh rat brain, liver homogenate, and intestinal flora. To quickly lock the target metabolites, we set the mass defect filter (MDF) in different ranges to screen metabolites with different molecular weight (MW). This strategy was defined as multi-stage MDF (mMDF). In addition, we performed relative quantitative analysis on all metabolites according to the peak area acquired by LC-IT-TOF/MS to overcome the challenge that metabolites are difficult to be quantified due to the lack of standards.

RESULTS

When MDF was set at 0.50 to 0.65 to screen metabolites with MW of 900 to 1200 Da, 6 novel metabolites were quickly found, and then identified as glucuronic acid binding, oxidation, dehydrogenation, methylation and hydrogenation products according to their LC and MS characteristics. When setting MDF at 0.42 - 0.52, 6 metabolites with MW of 600 to 900 Da were effectively screened and identified as Rg1, NG-R2, Rh1, Rg1+CH₂+2H and Rg1+CH₂. To screen the metabolites with MW of 300 to 600 Da, MDF was set at 0.25 - 0.42, and 4 novel metabolites were screened rapidly. The results of quantitative metabolism suggested that intestinal flora was the main metabolic site of NG-R1 in rat, and more than 60% of NG-R1 was converted to Rg1 by deglycosylation in the intestinal flora.

CONCLUSION

The mMDF strategy can significantly improve the research efficiency of qualitative metabolism of saponins. Although NG-R1 could be transformed into a variety of metabolites in rat liver and brain homogenate, it still existed mainly in prototype form. In the rat flora, NG-R1 mainly existed in the form of deglycosylated metabolite Rg1.

In Vitro Biotransformation of Total Glycosides in Qiwei Baizhu Powder by the Gut Microbiota of Normal and Diarrheal Mice: Novel Insight Into the Biotransformation of Multi-Glycosides by the Gut Microbiota

The gut microbiota (GM) is involved in the metabolism of glycosides and is beneficial for enhancing their bioactivity. However, the metabolism of multi-glycosides by the GM under normal and pathological conditions is unclear. In this study, the total glycosides (TG) of the traditional Chinese medicine (TCM) formula Qiwei Baizhu Powder (QWBZP) were extracted to represent a multi-glycoside system. Ultra-high-performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry (UHPLC-Q-TOF-MS/MS) was used to rapidly identify the components and in vitro metabolites of QWBZP-TG. The metabolic profiles of QWBZP-TG in the GM of normal and diarrheal mice were also compared. A total of 68 compounds and seven metabolites were identified in the QWBZP-TG and metabolic samples, respectively. Deglycosylation was the main metabolic pathway of in vitro multi-glycoside metabolism. Liquiritin apioside, isoliquiritin apioside, liquiritin, protopanaxadiol (PPD)-type, and oleanane (OLE)-type ginsenosides were relatively easy to metabolize by the GM. At first, the deglycosylation capability of the GM of normal mice was superior to that of diarrheal mice, but the deglycosylation capability of diarrheal mice gradually recovered and produced abundant deglycosylation metabolites. In conclusion, deglycosylation metabolites may be the bioactive components of QWBZP. Glycoside-bacteria interaction may be a key mechanism for QWBZP to therapy diarrhea.

Advances and challenges in ginseng research from 2011 to 2020: the phytochemistry, quality control, metabolism, and biosynthesis

Covering: 2011 to the end of 2020Panax species (Araliaceae), particularly P. ginseng, P. quinquefolius, and P. notoginseng, have a long history of medicinal use because of their remarkable tonifying effects, and currently serve as crucial sources for various healthcare products, functional foods, and cosmetics, aside from their vast clinical preparations. The huge market demand on a global scale prompts the continuous prosperity in ginseng research concerning the discovery of new compounds, precise quality control, ADME (absorption/disposition/metabolism/excretion), and biosynthesis pathways. Benefitting from the ongoing rapid development of analytical technologies, e.g. multi-dimensional chromatography (MDC), personalized mass spectrometry (MS) scan strategies, and multi-omics, highly recognized progress has been made in driving ginseng analysis towards "systematicness, integrity, personalization, and intelligentization". Herein, we review the advances in the phytochemistry, quality control, metabolism, and biosynthesis pathway of ginseng over the past decade (2011-2020), with 410 citations. Emphasis is placed on the introduction of new compounds isolated (saponins and polysaccharides), and the emerging novel analytical technologies and analytical strategies that favor ginseng's authentic use and global consumption. Perspectives on the challenges and future trends in ginseng analysis are also presented.

Red ginseng has stronger anti-aging effects compared to ginseng possibly due to its regulation of oxidative stress and the gut microbiota

BACKGROUND

Panax ginseng (PG) and red ginseng (RG) are considered to be effective anti-aging treatments. However, evidence of their therapeutic mechanisms and difference in anti-aging effects is lacking.

PURPOSE

To explore the potential therapeutic mechanisms of RG and PG in brain damage in D-Gal-induced aging mice, and evaluate the difference in anti-aging effects caused by their compositional differences.

METHODS

We first tested the chemical components in PG and RG. In D-Gal aging mouse model, RG and PG (800 mg/kg) were orally administered for 9 weeks. The mice performed the Radial Arm Maze (RAM) behavior test. We collected blood, brain tissue, and fecal samples and performed biochemical analysis, histological examination, western blot, and Illumina MiSeq sequencing analysis.

RESULTS

The results of component analysis showed that the total polyphenols and rare ginsenosides were present in RG in 3.2, and 2.2 fold greater concentrations, respectively, compared to PG, while the proportion of non-starch polysaccharides in the crude polysaccharides of RG was 1.94 fold greater than that of PG. In D-Gal-induced aging mice, both PG and RG could prevent the increase in acetylcholinesterase (AChE), and malondialdehyde (MDA) levels, and improved the expression of superoxide dismutase (SOD), and catalase (CAT) in the serum. Meanwhile, both PG and RG could ameliorate brain tissue architecture and behavioral trial. In addition, the D-Gal-induced translocation of nuclear factor-κB (NF-κB), as well as activation of the pro-apoptotic factors Caspase-3 and the PI3K/Akt pathways were inhibited by PG and RG. Overall, both PG and RG exerted anti-aging effects, with RG stronger than PG. Finally, although both PG and RG regulated the diversity of gut microbes, RG appeared to aggravate the increase in probiotics, such as Bifidobacterium and Akkermania, and the decrease in inflammatory bacteria to a greater extent compared to PG.

CONCLUSION

Our results suggest that RG is more conducive to delay the D-Gal-induced aging process than PG, with possible mechanisms including beneficial changes in brain structure, cognitive functions, oxidative stress inhibition, and gut microbiome structure and diversity than PG, These mechanisms may rely on the presence of more total polyphenols, rare ginsenosides and non-starch polysaccharides in RG.

Region-Specific Biomarkers and Their Mechanisms in the Treatment of Lung Adenocarcinoma: A Study of Panax quinquefolius from Wendeng, China

Panax quinquefolius, a popular medicinal herb, has been cultivated in China for many years. In this work, the region-specific profiles of metabolites in P. quinquefolius from Wendeng was investigated using liquid-chromatography-quadrupole-time-of-flight-(LC-Q-TOF)-based metabolomics analysis. The three most abundant biomarkers, identified as ginsenoside Rb₃, notoginsenoside R₁, and ginsenoside Rc, were the representative chemical components employed in the network pharmacology analysis. In addition, molecular docking and western blotting analyses revealed that the three compounds were effective binding ligands with Hsp90α, resulting in the inactivation of SRC and PI3K kinase, which eventually led to the inactivation of the Akt and ERK pathways and lung cancer suppression. The outcomes obtained herein demonstrated the intriguing chemical characteristics and potential functional activities of P. quinquefolius from Wendeng.

In Vitro Transformation of Protopanaxadiol Saponins in Human Intestinal Flora and Its Effect on Intestinal Flora

Protopanaxadiol (PPD)-type ginsenosides are the main ginsenosides in ginseng (Panax ginseng C. A. Meyer) with potential therapeutic effects on diseases related to intestinal flora imbalance. This study aimed to investigate the in vitro metabolism of protopanaxadiol ginsenosides in human intestinal flora and their effect on the flora. Rapid resolution liquid chromatography coupled with quadruple-time-of-flight mass spectrometry (RRLC-Q-TOF MS) was utilised for the transformation of ginsenoside constituents for sample identification. Using 16S rDNA gene sequencing technique, the effect of PPD-type ginsenosides on gut microflora was analysed based on the indices of microflora diversity and gut microflora. The sample was transformed for 6 h, and the metabolites were ginsenoside Rb1, Rc, Rb2, Rb3, CO, Gyp-IX, Gyp-XVII, CMc-1, F2, Rg3, CK, Rh2, and PPD. The metabolites were CK, Rh2, and PPD when the samples were transformed for 60 h. The intestinal microflora were subjected to high-throughput sequencing using the Illumina MiSeq 2500 sequencing platform. In comparison with the faecal sample from the blank group, the protopanaxadiol saponin group significantly increased the relative abundance of Firmicutes and significantly decreased Bacteroidetes and Proteobacteria at the phylum level, whereas it significantly increased the relative abundance of Prevotella_9, Faecalibacterium, and Dialister and significantly decreased Escherichia-Shigella, Dorea, and Lachnoclostridium at the genus level. This study provides a basis for the determination of the pharmacodynamic material basis and pharmacodynamic targets of PPD-type ginsenosides based on the intestinal flora.

Biotransformation of Ginsenosides (Rb1 , Rb2 , Rb3 , Rc) in Human Intestinal Bacteria and Its Effect on Intestinal Flora

Ginsenosides, including Rb₁ , Rb₂ , Rb₃ and Rc, belong to protopanaxadiol-type saponins in Panax ginseng C. A. Mey. Their contents are high in P. ginseng. They could inhibit oxidant stress, enhance immunity, lower blood sugar, resist tumor cells and facilitate other physiological activities. This study aimed to explore the interaction between ginsenosides Rb₁ , Rb₂ , Rb₃ and Rc and the intestinal flora of healthy people. It also sought to analyse the biotransformation products and pathways of these ginsenosides in in-vitro human intestinal bacteria and their effects on the diversity of human intestinal flora. Human intestinal bacteria were incubated with ginsenosides Rb₁ , Rb₂ , Rb₃ and Rc at 37 °C under anaerobic conditions. Samples were taken at different timepoints. The transformed products were identified by rapid high-resolution liquid chromatography-quadrupole time-of-flight mass spectrometry. After 48 h of transformation, the transformed product of ginsenosides Rb₁ , Rb₂ , Rb₃ and Rc was ginsenoside compound K. The transformation rates were 83.5 %, 88.7 %, 85.6 %, and 84.2 %. 16S rRNA sequencing technology was applied to the bioinformatic analysis of faecal samples incubated for 48 h. Relative to the blank control, the relative abundance of Firmicutes and Proteobacteria significantly increased at the phylum level. Moreover, the relative abundance of Bacteroidetes significantly decreased in ginsenosides Rb₁ , Rb₂ , Rb₃ and Rc. At the genus level, the relative abundance of Escherichia significantly increased, whereas that of Dorea, Prevotella and Megasphaera significantly decreased in all groups. These results showed that Rb₁ , Rb₂ , Rb₃ and Rc could improve the structure and diversity of human intestinal flora and balance the metabolic process.

Qualitatively and quantitatively investigating the metabolism of 20(S)-protopanaxadiol-type ginsenosides by gut microbiota of different species

Ginsenosides Rb1, Rb2, Rb3 and Rc, four major protopanaxadiol (PPD)-type ginsenosides, can be metabolized by gut microbiota. The composition of gut microbiota varies in different species. Existing publications have reported the metabolite fates of ginsenosides by gut microbiota from single species. However, their microbiota-related metabolic species differences have not been evaluated yet. In current study, in vitro anaerobic incubations of PPD-type ginsenosides with gut microbiota from humans, rabbits and rats were conducted. The metabolites of each ginsenoside were then identified by LC-MS. A total of 15 metabolites from the four ginsenosides were identified. The major metabolic pathways were stepwise removals of the C-20 and C-3 sugar moieties to obtain aglycone PPD. The results showed that the hydrolysis rate of C-20 terminal β-D-glucopyranosyl was significantly higher than those of α-L-arabinopyranosyl, β-D-xylopyranosyl and α-L-arabinofuranosyl in different species. The activity of β-glucosidase, the metabolic rates of parent compounds and the formation rates of their metabolites were significantly higher in gut microbiota from rabbits than from humans and rats. Our research draws researchers' attention to the species differences of microbiota-related drug metabolism.

Positive influence of gut microbiota on the effects of Korean red ginseng in metabolic syndrome: a randomized, double-blind, placebo-controlled clinical trial

Background

Ginseng, a traditional herbal medicine, has been used for thousands of years to treat various diseases including metabolic syndrome (MS). However, the underlying mechanism(s) of such beneficial actions of ginseng against MS is poorly understood. Emerging evidence indicates a close association of the host gut microbiota with MS. The present study was conducted to examine, whether the beneficial effects of Korean red ginseng (KRG) against MS could be influenced by gut microbial population and whether gut microbial profile could be considered a valuable biomarker for targeted treatment strategy for MS in compliance with the predictive, preventive, and personalized medicine (PPPM / 3PM).

Methods

This clinical study was a randomized, double-blind, placebo-controlled trial evaluating the effects of KRG treatment for 8 weeks on patients with MS. The anthropometric parameters, vital signs, metabolic biomarkers, and gut microbial composition through 16S rRNA gene sequencing were assessed at the baseline and endpoint. The impact of KRG was also evaluated after categorizing the subjects into responders and non-responders, as well as enterotypes 1 and 2 based on their gut microbial profile at the baseline.

Results

Fifty out of 60 subjects who meet the MS criteria completed the trial without showing adverse reactions. The KRG treatment caused a significant decrease in systolic blood pressure (SBP). Microbial analysis revealed a decrease in Firmicutes, Proteobacteria, and an increase in Bacteroidetes in response to KRG. In patient stratification analysis, the responders showing marked improvement in the serum levels of lipid metabolic biomarkers TC and LDL due to the KRG treatment exhibited higher population of both the family Lachnospiraceae and order Clostridiales compared to the non-responders. The homeostasis model assessment-insulin resistance (HOMA-IR) and insulin level were decreased in enterotype 1 (Bacteroides-abundant group) and increased in enterotype 2 (prevotella-abundant group) following the KRG treatment.

Conclusion

In this study, the effects of KRG on the glucose metabolism in MS patients were influenced by the relative abundances of gut microbial population and differed according to the individual enterotype. Therefore, the analysis of enterotype categories is considered to be helpful in predicting the effectiveness of KRG on glucose homeostasis of MS patients individually. This will further help to decide on the appropriate treatment strategy for MS, in compliance with the perspective of PPPM.

Simulated Gastrointestinal Biotransformation of Chlorogenic Acid, Flavonoids, Flavonolignans and Triterpenoid Saponins in Cecropia obtusifolia Leaf Extract

It is well known that biotransformation processes in the human body are crucial to form potentially bioactive metabolites from particular classes of natural products. However, little research has been conducted concerning the bioavailability of polyphenols, especially in the colon. The gastrointestinal stability and colonic biotransformation of the crude extract of the leaves of Cecropia obtusifolia, rich in flavone C-glycosides, was investigated under in vitro conditions, and the processing and interpretation of results were facilitated by using an automated machine learning model. This investigation revealed that flavone C-glycosides and flavonolignans from C. obtusifolia were stable throughout their passage in the simulated gastrointestinal tract including the colon phase. On the other hand, the colon bacteria extensively metabolized chlorogenic acid, flavonol, and triterpenoid O-glycosides. This investigation revealed that the colonic microbiota has an important role in the biotransformation of some chemical constituents of this extract.

Systematic characterization of the chemical constituents in vitro and prototypes in vivo of Dingkun Dan using ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry combined with the UNIFI™ software

Dingkun Dan (DKD), a famous traditional Chinese medicine, has been widely used in the treatment of irregular menstruation, leucorrhea abnormality, and postpartum gynecological diseases since Qing dynasty (1739). It comprises 30 flavors of Chinese medicinal materials, which results in its complex chemical composition. In this study, an integrative method was developed to rapidly characterize the chemical components of DKD using ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry combined with the UNIFI™ software. A total of 234 compounds, including 47 triterpenoid saponins, 55 flavonoids, and 38 alkaloids, were identified. Of them, 170 compounds were characterized initially and 61 compounds were identified unambiguously using reference standards. Under the same analysis conditions, 43 prototypical components, which were tentatively assigned as triterpenoid saponins, flavonoids, alkaloids, terpenoids, phenylpropanoids, and others, were absorbed in rat by serum pharmacochemistry analysis. DKD exhibited diverse pharmacological activities through the combined effect of these components. This study was the first systematic study of chemical components in vitro originating from 30 medicinal materials and prototypes in vivo of DKD, which could provide scientific evidence for explaining its therapeutic effect.

Different absorption and metabolism of ginsenosides after the administration of total ginsenosides and decoction of Panax ginseng

RATIONALE

Panax ginseng C.A. Meyer (PG), which contains polysaccharides and ginsenosides as the major bioactive components, has been used to promote health and treat diseases for thousands of years in China. Total ginsenosides were extracted from a decoction of Panax ginseng (GD), which included both ginsenosides and polysaccharides, and dissolved in water to obtain a total ginsenosides aqueous solution (TGAS). To study their absorption and metabolism, the pharmacokinetics (PK) and metabolites of ginsenosides in vivo were investigated after the administration of GD and TGAS.

METHODS

Rat and mice plasma samples were collected after the administration of GD and TGAS. Ultra-performance liquid chromatography coupled with time-of-flight mass spectrometry was used with the UNIFI platform to identify metabolites in the plasma sample. The pharmacokinetic parameters were calculated using a noncompartmental method in the Drug and Statistics software package.

RESULTS

Thirty ginsenoside metabolites were identified in mice plasma, of which only seven were found in the rat plasma after the administration of GD. The PK of ginsenosides Rb₁ , Rc, and Rd were also determined after the oral administration of GD and TGAS and showed significant differences in the pharmacokinetic parameters.

CONCLUSIONS

There was no difference in the biotransformation pathways after the oral administration of GD and TGAS, indicating that there was no influence of polysaccharides on the biotransformation of ginsenosides in vivo. However, the pharmacokinetic parameters were different after the administration of GD and TGAS, possibly because of the polysaccharides in GD. This study should be of significance in exploring the basis of PG bioactivities and lays the foundation for the further development of new drugs using PG.

Microbial Conversion of Protopanaxadiol-Type Ginsenosides by the Edible and Medicinal Mushroom Schizophyllum commune: A Green Biotransformation Strategy

Previous studies have shown that many kinds of microorganisms, including bacteria, yeasts, and filamentous fungi, can convert parent ginsenosides into minor ginsenosides. However, most microorganisms used for ginsenoside transformations may not be safe for food consumption and drug development. In this study, 24 edible and medicinal mushrooms were screened by high-performance liquid chromatography analyses for their ability to microbiologically transform protopanaxadiol (PPD)-type ginsenosides. We observed that the degradation of ginsenosides by Schizophyllum commune was inhibited by high concentrations of sugar in the culture medium. However, the inhibition was avoided by maintaining sugar concentration below 15 g L^-1. S. commune showed a strong ability to convert PPD-type ginsenosides (Rb₁, Rc, Rb₂, and Rd) into minor ginsenosides (F₂, C-O, C-Y, C-Mc₁, C-Mc, and C-K). The production and bioconversion rates of minor ginsenosides were significantly higher than those previously reported by food microorganisms. The fermentation process is efficient, nontoxic, eco-friendly, and economical, and the required biotransformation systems are readily available. This is the first report about the biotransformation of major ginsenosides into minor ginsenosides through fermentation by edible and medicinal mushrooms. Our results provide a green biodegradation strategy in transformation of ginsenosides using edible and medicinal mushrooms.

Inhibitory Effects of Ginsenoside Ro on the Growth of B16F10 Melanoma via Its Metabolites

Ginsenoside Ro (Ro), a major saponin derived and isolated from Panax ginseng C.A. Meyer, exerts multiple biological activities. However, the anti-tumour efficacy of Ro remains unclear because of its poor in vitro effects. In this study, we confirmed that Ro has no anti-tumour activity in vitro. We explored the anti-tumour activity of Ro in vivo in B16F10 tumour-bearing mice. The results revealed that Ro considerably suppressed tumour growth with no significant side effects on immune organs and body weight. Zingibroside R1, chikusetsusaponin IVa, and calenduloside E, three metabolites of Ro, were detected in the plasma of Ro-treated tumour-bearing mice and showed excellent anti-tumour effects as well as anti-angiogenic activity. The results suggest that the metabolites play important roles in the anti-tumour efficacy of Ro in vivo. Additionally, the haemolysis test demonstrated that Ro has good biocompatibility. Taken together, the findings of this study demonstrate that Ro markedly suppresses the tumour growth of B16F10-transplanted tumours in vivo, and its anti-tumour effects are based on the biological activity of its metabolites. The anti-tumour efficacy of these metabolites is due, at least in part, to its anti-angiogenic activity.

Characterization of ginsenoside compound K metabolites in rat urine and feces by ultra-performance liquid chromatography with electrospray ionization quadrupole time-of-flight tandem mass spectrometry

Ginsenoside compound K (CK) is an active metabolite of ginsenoside and has been shown to have ameliorative property in various diseases. However, the detailed in vivo metabolism of this compound has rarely been reported. In the present study, a method using liquid chromatography quadrupole time-of-flight tandem mass spectrometry together with multiple data processing techniques, including extracted ion chromatogram, multiple mass defect filter and MS/MS scanning, was developed to detect and characterize the metabolites of CK in rat urine and feces. After oral administration of CK at a dose of 50 mg/kg, urine and feces were collected for a period of time and subjected to a series of pretreatment. A total of 12 metabolites were tentatively or conclusively identified, comprising 11 phase I metabolites and a phase II metabolite. Metabolic pathways of CK has been proposed, including oxidation, deglycosylation, deglycosylation with sequential oxidation and dehydrogenation and deglycosylation with sequential glucuronidation. Relative quantitative analyses suggested that deglycosylation was the main metabolic pathway. The result could offer insights for better understanding of the mechanism of its pharmacological activities.

Ophiopogon Polysaccharide Promotes the In Vitro Metabolism of Ophiopogonins by Human Gut Microbiota

Gut microbiota play an important role in metabolism of intake saponins, and parallelly, the polysaccharides deriving from herbal products possess effects on gut microbiota. Ophiopogonis Radix is a common Chinese herb that is popularly used as functional food in China. Polysaccharide and steroidal saponin, e.g., ophiopogonin, mainly ophiopogonin D (Oph-D) and ophiopogonin D' (Oph-D'), are the major constituents in this herb. In order to reveal the role of gut microbiota in metabolizing ophiopogonin, an in vitro metabolism of Oph-D and Oph-D' by human gut microbiota, in combination with or without Ophiopogon polysaccharide, was conducted. A sensitive and reliable UPLC-MS/MS method was developed to simultaneously quantify Oph-D, Oph-D' and their final metabolites, i.e., ruscogenin and diosgenin in the broth of microbiota. An elimination of Oph-D and Oph-D' was revealed in a time-dependent manner, as well as the recognition of a parallel increase of ruscogenin and diosgenin. Ophiopogon polysaccharide was shown to stimulate the gut microbiota-induced metabolism of ophiopogonins. This promoting effect was further verified by increased activities of β-D-glucosidase, β-D-xylosidase, α-L-rhamnosidase and β-D-fucosidase in the broth. This study can be extended to investigate the metabolism of steroidal saponins by gut microbiota when combined with other herbal products, especially those herbs enriched with polysaccharides.

Using the UPLC-ESI-Q-TOF-MSE method and intestinal bacteria for metabolite identification in the nonpolysaccharide fraction from Bletilla striata

Bletilla striata (Thunb.) Reichb. f. (Orchidaceae), also known as Bai-ji, is a traditional Chinese herb that is widely used in Asia to treat hematemesis, hemoptysis, traumatic bleeding and other similar disorders. Most studies have focused on the pharmacological activities of polysaccharide extracts from B. striata. Our previous studies found that the nonpolysaccharide fraction from B. striata extract also has a hemostatic effect; however, the active constituents responsible for this pharmacological action are unclear. Thus, the metabolic profiles of the nonpolysaccharide fraction were investigated in Sprague-Dawley rats and intestinal bacteria models using ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry. Mass data were acquired by the MS^E method. Eight components including five prototypes and three metabolites were identified in rat biofluids after oral administration of the nonpolysaccharide fraction. The parent compounds underwent various metabolic processes, including hydrolysis, deglucosylation, glycosylation and sulfate conjugation. The results not only reveal the possible metabolic pathway, but also indicate the potential pharmacological components. Further mechanistic studies using nonpolysaccharide compounds of the B. striata extract are required to obtain potential candidate compounds.

New perspective on the metabolism of AD-1 in vivo: Characterization of a series of dammarane-type derivatives with novel metabolic sites and anticancer mechanisms of active oleanane-type metabolites

20(R)-25-methoxyl-dammarane-3β,12β,20-triol (AD-1, CN Patent: 201010107476.7) is a novel derivative of dammarane-type ginsenoside. AD-1 has been shown to inhibit cancer cell proliferation without significant host toxicity in vivo, and has excellent development potential as a new anti-cancer agent. This study was designed systematically to explore the metabolic pathway of ginseng sapogenins. The metabolism of drugs in the body is a complex biotransformation process where drugs are structurally modified to different molecules (metabolites) through various metabolizing enzymes. The compounds responsible for the effects of orally administered ginseng are believed to be metabolites produced in the gastrointestinal tract, so understanding the metabolism of the drug candidate can help to optimize its pharmacokinetics. In this study, faeces samples were collected and extracted after oral administration of AD-1. The 16 metabolites of AD-1 were isolated and identified for the first time with various chromatographic techniques, including semi-preparative high performance liquid chromatography, nuclear magnetic resonance spectroscopy, and mass spectrometry; of these 16 metabolites, 10 were novel compounds. We first discovered the biotransformation of dammarane-type sapogenins into oleanane-type sapogenins in rats and found a series of metabolites that changed, mainly at C-25 and C-29. This study provides new ideas for the metabolic pathway of ginseng sapogenins. The isolated compounds were screened for their effect on the viability and proliferation against cancer cell lines (Human A549, MCF-7, HELA, HO-8901 and U87). The discovery of novel active metabolites 3β,12β,21α,22β-Hydroxy-24-norolean-12-ene (M6) may lead to a new or improved drug candidate. For one, M6 could inhibit the growth of all the tested cancer cells. Among the tested cell lines, M6 exhibited the most remarkable inhibitory effect on ovarian cancer HO-8901 cells, with IC50 value of 2.086 μM. On this basis, we studied the anticancer mechanisms of M6. The results indicated that the pro-apoptotic feature of M6 acts via a mitochondrial pathway. Our results indicated that M6 exhibited a higher inhibitory effect on cancer-cell proliferation than AD-1 by inducing cell apoptosis. Our work provides data for future investigations on the metabolic mechanism of AD-1 in vivo and the potential for future research on developing a new drug.

Neuroprotective Effects of Red Ginseng Saponins in Scopolamine-Treated Rats and Activity Screening Based on Pharmacokinetics

Ginseng has been used to alleviate age-related dementia and memory deterioration for thousands of years. This study investigated the protective effect of red ginseng saponins against scopolamine-induced cerebral injury. Meanwhile, pharmacokinetics of ginsenosides in normal and scopolamine-treated rats were compared. After scopolamine injection, glutathione, catalase and superoxide dismutase levels were significantly decreased when compared with control group. Compared with SA group, pretreatment of rats with red ginseng saponins could increase glutathione, catalase and superoxide dismutase level. Treatment with red ginseng saponins significantly decreased malondialdehyde level. In the pharmacokinetic analysis, a pattern recognition analysis method was used to investigate the pharmacokinetics of the absorbed compounds in blood. The pharmacokinetic parameters of Rg1, Rg2, Rh3, Rg5 and Rk1 in model group had higher area under the curve (AUC), mean residence time (MRT) and peak plasma concentration (Cmax) values; area under the curve (AUC) values and peak plasma concentration (Cmax) of model group was significantly different from that of normal group (p < 0.05). The Cmax value of Rk3, Rh1, Rh2 and Rh4 in model group was higher than normal group, but their AUC values were not significantly different. There was no significantly difference in time at Cmax (Tmax), AUC and Cmax values of Rb1, Rb2 Re, Rc, Rd and Rf between the model and normal group. 16 ginsenosides were grouped into three separate clusters according to principal component analysis (PCA) score plot based on pharmacokinetic data. The results suggested red ginseng saponins have significant protective effect against scopolamine-induced memory deficit and scopolamine-induced rats could lead to the changes of pharmacokinetic behaviors of ginsenosides.

Effects of gut microbiota on the pharmacokinetics of protopanaxadiol ginsenosides Rd, Rg3, F2, and compound K in healthy volunteers treated orally with red ginseng

Background

It is well recognized that gut microbiota is involved in the biotransformation of ginsenosides by converting the polar ginsenosides to nonpolar bioactive ginsenosides. However, the roles of the gut microbiota on the pharmacokinetics of ginsenosides in humans have not yet been fully elucidated.

Methods

Red ginseng (RG) or fermented red ginseng was orally administered to 34 healthy Korean volunteers, and the serum concentrations of the ginsenosides were determined using liquid chromatography-tandem mass spectrometry. In addition, the fecal ginsenoside Rd- and compound K (CK)-forming activities were measured. Then, the correlations between the pharmacokinetic profiles of the ginsenosides and the fecal ginsenoside-metabolizing activities were investigated.

Results

For the RG group, the area under the serum concentration-time curve values of ginsenosides Rd, F2, Rg3, and CK were 8.20 ± 11.95 ng·h/mL, 4.54 ± 3.70 ng·h/mL, 36.40 ± 19.68 ng·h/mL, and 40.30 ± 29.83 ng·h/mL, respectively. For the fermented red ginseng group, the the area under curve from zero to infinity (AUC_∞) values of ginsenosides Rd, F2, Rg3, and CK were 187.90 ± 95.87 ng·h/mL, 30.24 ± 41.87 ng·h/mL, 28.68 ± 14.27 ng·h/mL, and 137.01 ± 96.16 ng·h/mL, respectively. The fecal CK-forming activities of the healthy volunteers were generally proportional to their ginsenoside Rd-forming activities. The area under the serum concentration-time curve value of CK exhibited an obvious positive correlation (r = 0.566, p < 0.01) with the fecal CK-forming activity.

Conclusion

The gut microbiota may play an important role in the bioavailability of the nonpolar RG ginsenosides by affecting the biotransformation of the ginsenosides.

UPLC-QTOF/MS-Based Nontargeted Metabolomic Analysis of Mountain- and Garden-Cultivated Ginseng of Different Ages in Northeast China

Aiming at further systematically comparing the similarities and differences of the chemical components in ginseng of different ages, especially comparing the younger or the older and mountain-cultivated ginseng (MCG), 4, 5, 6-year-old cultivated ginseng (CG) and 12, 20-year-old MCG were chosen as the analytical samples in the present study. The combination of UPLC-QTOF-MS^E, UNIFI platform and multivariate statistical analysis were developed to profile CGs and MCGs. By the screening analysis based on UNIFI, 126 chemical components with various structural types were characterized or tentatively identified from all the CG and MCG samples for the first time. The results showed that all the CG and MCG samples had the similar chemical composition, but there were significant differences in the contents of markers. By the metabolomic analysis based on multivariate statistical analysis, it was shown that CG_{4⁻6 years}, MCG_{12 years} and MCG_{20 years} samples were obviously divided into three different groups, and a total of 17 potential age-dependent markers enabling differentiation among the three groups of samples were discovered. For differentiation from other two kinds of samples, there were four robust makers such as α-linolenic acid, 9-octadecenoic acid, linoleic acid and panaxydol for CG_{4⁻6 years}, five robust makers including ginsenoside Re₁, -Re₂, -Rs₁, malonylginsenoside Rb₂ and isomer of malonylginsenoside Rb₁ for MCG_{20 years}, and two robust makers, 24-hydroxyoleanolic acid and palmitoleic acid, for MCG_{12 years} were discovered, respectively. The proposed approach could be applied to directly distinguish MCG root ages, which is an important criterion for evaluating the quality of MCG. The results will provide the data for the further study on the chemical constituents of MCG.

Stepwise targeted matching strategy from in vitro to in vivo based on ultra-high performance liquid chromatography tandem mass spectrometry technology to quickly identify and screen pharmacodynamic constituents

The study of in vivo pharmacodynamic constituents (PCs) of traditional Chinese medicine (TCM) is important for providing new clues for TCM applications in clinical therapies in modern medicine. However, detecting and identifying PCs from complex biological samples remain a challenge. In this study, a practical and novel stepwise targeted matching and longitudinal analysis strategy from in vitro to in vivo was developed. This strategy combined with ultra-high performance liquid chromatography tandem mass spectrometry was applied to quickly discover PCs in TCM. This approach was developed based on a core perception that all drugs taken orally might be transformed progressively and orderly from the intestinal tract, liver, and blood to the target organ. Based on this core perception, stepwise targeted matching was orderly and efficiently accomplished by multiple screening processes that were based on a stepwise enriched in-house library. Ginseng (Panax ginseng) was set as the example of herbal medicine for validating the reliability and availability of this approach. By applying this novel strategy to the stepwise screening of metabolites, we successfully identified 113 metabolites, among which 59 compounds were defined as prototypes. Based on the in vivo metabolites, network pharmacology analysis was applied to screen the PCs of ginseng and clarified the action mechanism of ginseng for the treatment of Alzheimer's disease (AD). A total of 27 herbal constituents and 64 related targets shared commonly by compounds and AD were integrated via target network pharmacology analysis. These results demonstrated that this original approach will greatly improve high-throughput screening of metabolites and PCs on AD. It also can explicate the mechanism of action of TCM. Furthermore, this strategy is practicable to identify metabolites and screen PCs in other herbal medicines.

Changes in intestinal microbiota affect metabolism of ginsenoside Re

Ginsenoside Re, an active ingredient in Panax ginseng, is widely used as a therapeutic and nutriment. The intestinal microbiota plays crucial roles in modulating the pharmacokinetics and pharmacological actions of ginsenoside Re. The aim of this study was to explore the relationship between bacterial community variety and the metabolic profiles of ginsenoside Re. We developed two models with intestinal dysbacteriosis: a pseudo-germ-free model induced by a nonabsorbable antimicrobial mixture (ATM), and Qi-deficiency model established via over-fatigue and acute cold stress (OACS). First, the bacterial community structures in control, ATM and OACS rats were compared via 16S ribosomal RNA amplicon sequencing. Then, the gut microbial metabolism of ginsenoside Re was assessed qualitatively and quantitatively in the three groups by UPLC-Q-TOF/MS and HPLC-TQ-MS, respectively. Ten metabolites of ginsenoside Re were detected and tentatively identified, three of which were novel. Moreover, owing to significant differences in bacterial communities, deglycosylated products, as the main metabolites of ginsenoside Re, were produced at lower levels in ATM and OACS models. Importantly, the levels of these deglycosylated metabolites correlated with alterations in Prevotella, Lactobacillus and Bacteroides populations, as well as glycosidase activities. Collectively, biotransformation of ginsenoside Re is potentially influenced by regulation of the composition of intestinal microbiota and glycosidase activities.

Determination of the transformation of ginsenosides in Ginseng Radix et Rhizoma during decoction with water using ultra-fast liquid chromatography coupled with tandem mass spectrometry

This study was conducted to determine the variations of ginsenosides in Ginseng Radix et Rhizoma when using different preparation solvents and explore the major factors for changes. With an established ultra-fast liquid chromatography coupled with tandem mass spectrometry method which could quantify 52 ginsenosides, the extraction differences were characterized and compared using different solvents (water, 70% aqueous ethanol, and ethanol). Subsequently, a series of aqueous solutions with different pH were prepared to test the influence of pH to the changes of ginsenosides. Meanwhile, acetic acid and aspartic acid were used to verify whether the reaction had a relationship with the kind of acids. After refluxing with water, not only highly polar ginsenosides were extracted, some less polar ginsenosides such as ginsenoside Rg₃ , Rg₅ , Rk₁ , and Rh₂ occurred or increased rapidly. Further experiments indicated that less polar ginsenosides were easier to generate at low pH values, and the reaction was only related to pH other than what kind of acids were used. It is the first time to elaborate the contents variation of 52 ginsenosides when using different extraction methods. The results indicated that decoction with water could enhance the transformation of highly polar ginsenosides to less polar ginsenosides and the process was pH dependent.

Biotransformation of Dioscorea nipponica by Rat Intestinal Microflora and Cardioprotective Effects of Diosgenin

Studying the biotransformation of natural products by intestinal microflora is an important approach to understanding how and why some medicines-particularly natural medicines-work. In many cases, the active components are generated by metabolic activation. This is critical for drug research and development. As a means to explore the therapeutic mechanism of Dioscorea nipponica (DN), a medicinal plant used to treat myocardial ischemia (MI), metabolites generated by intestinal microflora from DN were identified, and the cardioprotective efficacy of these metabolites was evaluated. Our results demonstrate that diosgenin is the main metabolite produced by rat intestinal microflora from DN. Further, our results show that diosgenin protects the myocardium against ischemic insult through increasing enzymatic and nonenzymatic antioxidant levels in vivo and by decreasing oxidative stress damage. These mechanisms explain the clinical efficacy of DN as an anti-MI drug.

Human Gastrointestinal Metabolism of the Cistanches Herba Water Extract in Vitro: Elucidation of the Metabolic Profile Based on Comprehensive Metabolite Identification in Gastric Juice, Intestinal Juice, Human Intestinal Bacteria, and Intestinal Microsomes

Cistanches Herba is taken orally as a health food supplement and medicinal plant in Asian countries. It consists of the stems of Cistanche deserticola (CD) and Cistanche tubulosa (CT). The gastrointestinal metabolism of the multiple components contained in Cistanches Herba is crucial for the discovery of bioactive constituents. This study aims to elucidate the comprehensive metabolic profile of the Cistanches Herba water extract by simulating human gastrointestinal metabolism in vitro independently and sequentially using four models: gastric juice, intestinal juice, human intestinal bacteria, and human intestinal microsomes. A total of 35 and 18 metabolites were characterized from CD and CT water extracts, respectively. These metabolites were formed through reduction, methylation, dimethylation, deglycosylation, decaffeoyl, derhamnose, dehydrogenation, and glucuronidation. The difference in metabolites of the Cistanches Herba water extract and single compounds and the difference in metabolites of CD and CT water extracts were caused by the oligosaccharides and polysaccharides in Cistanches Herba.

Biotransformation of Total Saponins in Siraitia Fructus by Human Intestinal Microbiota of Normal and Type 2 Diabetic Patients: Comprehensive Metabolite Identification and Metabolic Profile Elucidation Using LC-Q-TOF/MS

Siraitia fructus, known as Luo-Han-Guo (LHG) in Chinese, shows good antidiabetic activity. Gut microbiota have emerged as parameter of the pathophysiology of type 2 diabetes (t2D) mellitus. In this study, in vitro biotransformation of LHG extract by t2D and normal human intestinal microbiota was analyzed using ultraperformance liquid chromatography with time-of-flight mass spectrometry. A total of 19 and 12 metabolites were characterized in t2D and normal human intestinal microbiota, respectively. These metabolites were formed by a series of metabolic reactions including deglycosylation, oxidation, isomerization, and/or deoxidation. The metabolite classes of LHG extract in normal and t2D human intestinal microbiota were nearly the same, but oxidation and isomerization reactions were usually present in t2D human intestinal bacteria. This might be due to metabolic activation by pathological human intestinal bacteria. Our study indicates that there are differences in the biotransformation of LHG extract in normal and t2D human intestinal bacteria.

Biotransformation of Panax ginseng extract by rat intestinal microflora: identification and quantification of metabolites using liquid chromatography-tandem mass spectrometry

BACKGROUND

In general, after Panax ginseng is administered orally, intestinal microbes play a crucial role in its degradation and metabolization process. Studies on the metabolism of P. ginseng by microflora are important for obtaining a better understanding of their biological effects.

METHODS

In vitro biotransformation of P. ginseng extract by rat intestinal microflora was investigated at 37°C for 24 h, and the simultaneous determination of the metabolites and metabolic profile of P. ginseng saponins by rat intestinal microflora was achieved using LC-MS/MS.

RESULTS

A total of seven ginsenosides were detected in the P. ginseng extract, including ginsenosides Rg1, Re, Rf, Rb1, Rc, Rb2, and Rd. In the transformed P. ginseng samples, considerable amounts of deglycosylated metabolite compound K and Rh1 were detected. In addition, minimal amounts of deglycosylated metabolites (ginsenosides Rg2, F1, F2, Rg3, and protopanaxatriol-type ginsenosides) and untransformed ginsenosides Re, Rg1, and Rd were detected at 24 h. The results indicated that the primary metabolites are compound K and Rh1, and the protopanaxadiol-type ginsenosides were more easily metabolized than protopanaxatriol-type ginsenosides.

CONCLUSION

This is the first report of the identification and quantification of the metabolism and metabolic profile of P. ginseng extract in rat intestinal microflora using LC-MS/MS. The current study provided new insights for studying the metabolism and active metabolites of P. ginseng.

Understanding the Molecular Mechanisms of the Interplay Between Herbal Medicines and Gut Microbiota

Herbal medicines (HMs) are much appreciated for their significant contribution to human survival and reproduction by remedial and prophylactic management of diseases. Defining the scientific basis of HMs will substantiate their value and promote their modernization. Ever-increasing evidence suggests that gut microbiota plays a crucial role in HM therapy by complicated interplay with HM components. This interplay includes such activities as: gut microbiota biotransforming HM chemicals into metabolites that harbor different bioavailability and bioactivity/toxicity from their precursors; HM chemicals improving the composition of gut microbiota, consequently ameliorating its dysfunction as well as associated pathological conditions; and gut microbiota mediating the interactions (synergistic and antagonistic) between the multiple chemicals in HMs. More advanced experimental designs are recommended for future study, such as overall chemical characterization of gut microbiota-metabolized HMs, direct microbial analysis of HM-targeted gut microbiota, and precise gut microbiota research model development. The outcomes of such research can further elucidate the interactions between HMs and gut microbiota, thereby opening a new window for defining the scientific basis of HMs and for guiding HM-based drug discovery.