Simultaneous determination of original, degraded ginsenosides and aglycones by ultra high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry for quantitative evaluation of Du-Shen-Tang, the decoction of ginseng

Metals/bisulfite system involved generation of 24-sulfonic-25-ene ginsenoside Rg1, a potential quality control marker for sulfur-fumigated ginseng

Ginseng is a most popular health-promoting food with ginsenosides as its main bioactive ingredients. Illegal sulfur-fumigation causes ginsenosides convert to toxic sulfur-containing derivatives, and reduced the efficacy/safety of ginseng. 24-sulfo-25-ene ginsenoside Rg1 (25-ene SRg1), one of the sulfur-containing derivatives, is a potential quality control marker of fumigated ginseng, but with low accessibility owing to its unknown generation mechanism. In this study, metals/bisulfite system involved generation mechanism was investigated and verified. The generation of 25-ene SRg1 in sulfur-fumigated ginseng is that SO2, formed during sulfur-fumigation, reacted with water and ionized into HSO3-. On the one hand, under the metals/bisulfite system, HSO3- generates HSO5- and free radicals which converted ginsenoside Rg1 to 24,25-epoxide Rg1; on the other hand, as a nucleophilic group, HSO3- reacted with 24,25-epoxide Rg1 and further dehydrated to 25-ene SRg1. This study provided a technical support for the promotion of 25-ene SRg1 as the characteristic quality control marker of sulfur-fumigated ginseng.

Phytochemistry of ginsenosides: Recent advancements and emerging roles

Ginsenosides, a group of tetracyclic saponins, accounts for the nutraceutical and pharmaceutical relevance of the ginseng (Panax sp.) herb. Owing to the associated therapeutic potential of ginsenosides, their demand has been increased significantly in the last two decades. However, a slow growth cycle, low seed production, and long generation time of ginseng have created a gap between the demand and supply of ginsenosides. The biosynthesis of ginsenosides involves an intricate network of pathways with multiple oxidation and glycosylation reactions. However, the exact functions of some of the associated genes/proteins are still not completely deciphered. Moreover, ginsenoside estimation and extraction using analytical techniques are not feasible with high efficiency. The present review is a step forward in recapitulating the comprehensive aspects of ginsenosides including their distribution, structural diversity, biotransformation, and functional attributes in both plants and animals including humans. Moreover, ginsenoside biosynthesis in the potential plant sources and their metabolism in the human body along with major regulators and stimulators affecting ginsenoside biosynthesis have also been discussed. Furthermore, this review consolidates biotechnological interventions to enhance the biosynthesis of ginsenosides in their potential sources and advancements in the development of synthetic biosystems for efficient ginsenoside biosynthesis to meet their rising industrial demands.

Anti-tumor activities of Panax quinquefolius saponins and potential biomarkers in prostate cancer

BACKGROUND

Prostate carcinoma is the second most common cancer among men worldwide. Developing new therapeutic approaches and diagnostic biomarkers for prostate cancer (PC) is a significant need. The Chinese herbal medicine Panax quinquefolius saponins (PQS) have been reported to show anti-tumor effects. We hypothesized that PQS exhibits anti-cancer activity in human PC cells and we aimed to search for novel biomarkers allowing early diagnosis of PC.

METHODS

We used the human PC cell line DU145 and the prostate epithelial cell line PNT2 to perform cell viability assays, flow cytometric analysis of the cell cycle, and FACS-based apoptosis assays. Microarray-based gene expression analysis was used to display specific gene expression patterns and to search for novel biomarkers. Western blot and quantitative real-time PCR were performed to demonstrate the expression levels of multiple cancer-related genes.

RESULTS

Our data showed that PQS inhibited the viability of DU145 cells and induced cell cycle arrest at the G1 phase. A significant decrease in DU145 cell invasion and migration were observed after 24 h treatment by PQS. PQS up-regulated the expression levels of p21, p53, TMEM79, ACOXL, ETV5, and SPINT1 while it down-regulated the expression levels of bcl2, STAT3, FANCD2, DRD2, and TMPRSS2.

CONCLUSION

PQS promoted cells apoptosis and inhibited the proliferation of DU145 cells, which suggests that PQS may be effective for treating PC. TMEM79 and ACOXL were expressed significantly higher in PNT2 than in DU145 cells and could be novel biomarker candidates for PC diagnosis.

The dual roles of ginsenosides in improving the anti-tumor efficiency of cyclophosphamide in mammary carcinoma mice

ETHNOPHARMACOLOGICAL RELEVANCE

Cyclophosphamide (CTX) is a first line chemotherapeutic agent, but often limited for its unstable therapeutic effect and serious side effects. Ginsenosides could facilitate the anti-tumor efficiency of CTX, including benefiting therapeutic effect and decreasing side effects.

AIM OF THE STUDY

To investigate the potential mechanism of ginsenosides on benefiting the anti-tumor efficiency of CTX.

MATERIALS AND METHODS

Mammary carcinoma mice were applied to investigate the anti-tumor efficiency and potential mechanism of combinational treatment of ginsenosides and CTX. Therapeutic effect was evaluated based on survival rate, tumor burden, tumor growth inhibition rate, and apoptosis and histological changes of tumor tissues. Anti-tumor immunity was studied by measuring serum level of anti-tumor cytokines. Gut mucositis, one of lethal side effects of CTX, was evaluated by diarrhea degree, gut permeability and tight junction proteins expressions. Gut microbial diversity was analyzed by 16S rRNA gene sequencing, and fecal transplant and antibiotics sterilized animals were performed to evaluate the therapeutic effect of gut microbiota on tumor suppression.

RESULTS

Ginsenosides facilitated the therapeutic effect of CTX in mice, which manifested as prolonged survival rate, decreased tumor burden, as well as enhanced tumor growth inhibition rate and apoptosis. The favoring effect was related to elevation of anti-tumor immunity which manifested as the increased anti-tumor cytokines (INF-γ, IL-17, IL-2 and IL-6). Further studies indicated the elevation was ascribed to ginsenosides promoted reproduction of gut probiotics including Akkermansia, Bifidobacterium and Lactobacillus. Moreover, co-administration of ginsenosides in mice alleviated CTX-induced gut mucositis, including lower gut permeability, less diarrhea, less epithelium damage and higher tight junction proteins. Further researches suggested the alleviation was related to ginsenosides activated Nrf2 and inhibited NFκB pathways.

CONCLUSION

Ginsenosides show dual roles to facilitate the anti-tumor efficiency of CTX, namely promote the anti-tumor immunity through maintaining gut microflora and ameliorate gut mucositis by modulating Nrf2 and NFκB pathways.

Differences in Intestinal Metabolism of Ginseng Between Normal and Immunosuppressed Rats

BACKGROUND AND OBJECTIVE

Ginseng is usually consumed as a dietary supplement for health care in the normal state or prescribed as a herbal medicine in pathologic conditions. Although metabolic studies of ginseng are commonly performed on healthy organisms, the metabolic characteristics in pathologic organisms remain unexplored. This study aimed to uncover the difference in intestinal metabolism of ginseng between normal and cyclophosphamide-induced immunosuppressed rats and further discuss the potential mechanisms involved.

METHODS

Twelve Sprague-Dawley rats (6-8 weeks old) were randomly divided into two groups: the normal group (NG) and immunosuppressed group (ISG). Rats in the NG and ISG groups were intraperitoneally administered normal saline and cyclophosphamide injections (40 mg/kg) on the 1st, 2nd, 3rd and 10th days; on the 12th day, all rats were intragastrically administered ginseng water extract (900 mg/kg). The difference in intestinal metabolism of ginseng was compared using an ultra-high-performance liquid chromatography coupled with quadruple time-of-flight mass spectrometry-based metabolomics approach, and the diversities of gut microbiota were analyzed by 16S rRNA gene sequencing between the two groups.

RESULTS

The intestinal metabolomic characteristics of ginseng were significantly different between the normal and immunosuppressed rats, with the ginsenoside F₂ (F₂), 20S-ginsenoside Rg₃ (20(S)-Rg₃), pseudo-ginsenoside Rt₅ (Pseudo-Rt₅), ginsenoside Rd (Rd), ginsenoside Rh₁ (Rh₁), 20S-ginsenoside Rg₁ (20(S)-Rg₁), ginsenoside compound K (CK), ginsenoside Rg₂ (Rg₂) and 20S-panaxatriol (S-PPT) more abundant in immunosuppressed ones (P < 0.05). Additionally, the composition of gut microbiota was remarkably altered in the two groups, with some specific bacterial communities such as Bacteroides spp., Eubacterium spp. and Lachnospiraceae_UCG-010 spp. increased and Bifidobacterium spp. decreased in immunosuppressed rats compared with normal ones.

CONCLUSION

The intestinal metabolism of ginseng in immunosuppressed rats was significantly different from that in normal ones, which might be partly attributed to the changes in the intensity of specific gut bacteria. The outcomes of this study could provide scientific data for rationalization of ginseng use as both a dietary supplement and herbal medicine.

Effect of sulfur-fumigation process on ginseng: Metabolism and absorption evidences

ETHNOPHARMACOLOGICAL RELEVANCE

Sulfur-fumigation has been developed to prevent insects and molds during post-harvest handling of Panax ginseng C.A. Mey (ginseng) in the near decades. Our previous study indicated sulfur-fumigation could transform ginsenosides, the active components of ginseng, into sulfur-containing derivatives (SFCDs), the artifacts with unknown toxicity. However, whether the biotransformation could be occurred and absorption characteristics between ginsenosides and SFCDs are still needed to further investigate.

AIM OF THE STUDY

To evaluate the effect of sulfur-fumigation process on ginseng through comparing the metabolic profile and absorption characteristics between ginsenoside Rg1, Re and their SFCDs.

MATERIALS AND METHODS

Intestinal microflora and liver S9 fraction were utilized to compare the metabolic profile, and single-pass intestinal perfusion and Caco-2 cell models were applied to compare the absorption characteristics, between Rg1, Re and their SFCDs.

RESULTS

Rg1 and Re were metabolized to 7 none sulfur-containing metabolites, while their SFCDs were metabolized to 18 sulfur-containing metabolites. The intestinal absorption and transport of Rg1 and Re were much greater than their SFCDs. Besides, the uptakes of Rg1 and Re were transport-dependent, but their SFCDs were non-transport-dependent.

CONCLUSION

Ginsenosides and their SFCDs could not be bio-transformed with each other and their absorption characteristics were quite different, which suggested that sulfur-fumigation is not a feasible post-harvest process of ginseng.

Characterization of a Novel Ginsenoside MT1 Produced by an Enzymatic Transrhamnosylation of Protopanaxatriol-Type Ginsenosides Re

BACKGROUND

Ginsenosides, triterpene saponins of Panax species, are considered the main active ingredients responsible for various pharmacological activities. Herein, a new protopanaxatriol-type ginsenoside called "ginsenoside MT1" is described; it was accidentally found among the enzymatic conversion products of ginsenoside Re.

METHOD

We analyzed the conversion mechanism and found that recombinant β-glucosidase (MT619) transglycosylated the outer rhamnopyranoside of Re at the C-6 position to glucopyranoside at C-20. The production of MT1 by trans-rhamnosylation was optimized and pure MT1 was obtained through various chromatographic processes.

RESULTS

The structure of MT1 was elucidated based on spectral data: (20S)-3β,6α,12β,20-tetrahydroxydammarene-20-O-[α-L-rhamnopyranosyl(1→2)-β-D-glucopyranoside]. This dammarane-type triterpene saponin was confirmed as a novel compound.

CONCLUSION

Based on the functions of ginsenosides with similar structures, we believe that this ginsenoside MT1 may have great potential in the development of nutraceutical, pharmaceutical or cosmeceutical products.

High-density immobilization of a ginsenoside-transforming β-glucosidase for enhanced food-grade production of minor ginsenosides

Use of recombinant glycosidases is a promising approach for the production of minor ginsenosides, e.g., Compound K (CK) and F₁, which have potential applications in the food industry. However, application of these recombinant enzymes for food-grade preparation of minor ginsenosides are limited by the lack of suitable expression hosts and low productivity. In this study, Corynebacterium glutamicum ATCC13032, a GRAS strain that has been used extensively for the industrial-grade production of additives for foodstuffs, was employed to express a novel β-glucosidase (MT619) from Microbacterium testaceum ATCC 15829 with high ginsenoside-transforming activity. A cellulose-binding module was additionally fused to the N-terminus of MT619 for immobilization on cellulose, which is an abundant and safe material. Via one-step immobilization, the fusion protein in cell lysates was efficiently immobilized on regenerated amorphous cellulose at a high density (maximum 984 mg/g cellulose), increasing the enzyme concentration by 286-fold. The concentrated and immobilized enzyme showed strong conversion activities against protopanaxadiol- and protopanaxatriol-type ginsenosides for the production of CK and F₁. Using gram-scale ginseng extracts as substrates, the immobilized enzyme produced 7.59 g/L CK and 9.42 g/L F₁ in 24 h. To the best of our knowledge, these are the highest reported product concentrations of CK and F₁, and this is the first time that a recombinant enzyme has been immobilized on cellulose for the preparation of minor ginsenosides. This safe, convenient, and efficient production method could also be effectively exploited in the preparation of food-processing recombinant enzymes in the pharmaceutical, functional food, and cosmetics industries.

Quality evaluation of Panax quinquefolium from different cultivation regions based on their ginsenoside content and radioprotective effects on irradiated mice

Ginsenosides are one of major types of bioactive compounds in American ginseng (AG) and utilized to assess the quality of various AG samples. The contents of ginsenosides showed cultivation region-related variation, which is possibly associated with AG’s pharmacological effect difference. Therefore, to reveal the quality difference of AGs in different cultivation regions, AG samples from seven cultivation regions were evaluated via analyzing their contents of nine ginsenosides and the biochemical parameters in AG-treated irradiated mice. Pre-administration of AG decoctions could reversely modulate the irradiation-induced changes of antioxidant enzymatic activity, cytokine level and hormone level in irradiated mice, which demonstrated that AG had the radioprotective effects due to its antioxidative, immunomodulatory and anti-inflammatory properties. However, this radioprotection effect varied among different cultivation regions of AGs. Collectively, Beijing and Canada-cultivated AGs had the best radioprotection. Heilongjiang and Jilin-originated AGs had the similar pharmacological effects while USA, Shandong and Shaanxi-grown AGs had closer pharmacological effects. This biochemical measurements-based PCA and heatmap clustering of AGs from seven cultivation regions was nearly consistent with ginsencoside content- and the previous serum metabolome-based analyses. However, the pearson correlation analysis revealed that only Rb3 and Rd were significantly correlated with some of assayed biochemical parameters in irradiated mice pretreated with different cultivation regions of AG extracts.

UPLC-QTOF-MS/MS-guided isolation and purification of sulfur-containing derivatives from sulfur-fumigated edible herbs, a case study on ginseng

In this study, a novel ultra-performance liquid chromatography coupled with quadrupole/time-of-flight mass spectrometry (UPLC-QTOF-MS/MS)-guidance strategy was proposed for preparation of sulfur-containing derivatives in sulfur-fumigated edible herbs. Being versatile in both chromatographic separation and mass spectrometric detection, UPLC-QTOF-MS/MS was inducted into each experimental step for multifaceted purposes including finding, tracking, purity determination and structural elucidation of targeted compounds as well as UPLC-HPLC chromatographic conditions transplantation, whereby the isolation and purification procedures were greatly facilitated. Using this strategy, a new sulfur-containing ginsenoside Rg₁ derivative (named compound I) was obtained from sulfur-fumigated ginseng. The chemical structure of compound I was elucidated to be (3β, 6α, 12β)-3, 12-dihydroxydammar-25-ene-6, 20-diylbis-β-d-glucopyranoside, 24-sulfonic acid by QTOF-MS/MS, ¹H-NMR and ¹³C-NMR analysis, and its generation mechanisms by sulfur-fumigation were accordingly discussed. The research deliverable suggests that the UPLC-QTOF-MS/MS-guidance strategy is promising for targeted preparation of sulfur-containing derivatives from sulfur-fumigated edible herbs.

Qualitative and quantitative characterization of secondary metabolites and carbohydrates in Bai-Hu-Tang using ultraperformance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry and ultraperformance liquid chromatography coupled with photodiode array detector

Bai-Hu-Tang (BHT), a classic traditional Chinese medicine (TCM) formula used for clearing heat and promoting body fluid, consists of four traditional Chinese medicines, i.e., Gypsum Fibrosum (Shigao), Anemarrhenae Rhizoma (Zhimu), Glycyrrhizae Radix et Rhizoma Praeparata cum Melle (Zhigancao), and nonglutinous rice (Jingmi). The chemical composition of BHT still remains largely elusive thus far. To qualitatively and quantitatively characterize secondary metabolites and carbohydrates in BHT, here a combination of analytical approaches using ultraperformance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry and ultraperformance liquid chromatography coupled with photodiode array detector was developed and validated. A total of 42 secondary metabolites in BHT were tentatively or definitely identified, of which 10 major chemicals were quantified by the extracting ion mode of quadrupole time-of-flight mass spectrometry. Meanwhile, polysaccharides, oligosaccharides, and monosaccharides in BHT were also characterized via sample pretreatment followed by sugar composition analysis. The quantitative results indicated that the determined chemicals accounted for 35.76% of the total extract of BHT, which demonstrated that the study could be instrumental in chemical dissection and quality control of BHT. The research deliverables not only laid the root for further chemical and biological evaluation of BHT, but also provided a comprehensive analytical strategy for chemical characterization of secondary metabolites and carbohydrates in traditional Chinese medicine formulas.

Ginseng alleviates cyclophosphamide-induced hepatotoxicity via reversing disordered homeostasis of glutathione and bile acid

Cyclophosphamide (CP), a chemotherapeutic agent, is restricted due to its side effects, especially hepatotoxicity. Ginseng has often been clinically used with CP in China, but whether and how ginseng reduces the hepatotoxicity is unknown. In this study, the hepatoprotective effects and mechanisms under the combined usage were investigated. It was found that ginseng could ameliorate CP-induced elevations of ALP, ALT, ALS, MDA and hepatic deterioration, enhance antioxidant enzymes’ activities and GSH’s level. Metabolomics study revealed that 33 endogenous metabolites were changed by CP, 19 of which were reversed when ginseng was co-administrated via two main pathways, i.e., GSH metabolism and primary bile acids synthesis. Furthermore, ginseng could induce expression of GCLC, GCLM, GS and GST, which associate with the disposition of GSH, and expression of FXR, CYP7A1, NTCP and MRP 3, which play important roles in the synthesis and transport of bile acids. In addition, NRF 2, one of regulatory elements on the expression of GCLC, GCLM, GS, GST, NTCP and MRP3, was up-regulated when ginseng was co-administrated. In conclusion, ginseng could alleviate CP-induced hepatotoxicity via modulating the disordered homeostasis of GSH and bile acid, which might be mediated by inducing the expression of NRF 2 in liver.