Microbial transformation of 20(S)-protopanaxatriol-type saponins by Absidia coerulea

Production of rare ginsenosides by biotransformation of Panax notoginseng saponins using Aspergillus fumigatus

Panax notoginseng saponins (PNS) are the main active components of Panax notoginseng. But after oral administration, they need to be converted into rare ginsenosides by human gut microbiota and gastric juice before they can be readily absorbed into the bloodstream and exert their effects. The sources of rare ginsenosides are extremely limited in P. notoginseng and other medical plants, which hinders their application in functional foods and drugs. Therefore, the production of rare ginsenosides by the transformation of PNS using Aspergillus fumigatus was studied in this research. During 50 days at 25 ℃ and 150 rpm, A. fumigatus transformed PNS to 14 products (1-14). They were isolated by varied chromatographic methods, such as silica gel column chromatography, Rp-C18 reversed phase column chromatography, semi-preparative HPLC, Sephadex LH-20 gel column chromatography, and elucidated on the basis of their 1H-NMR, 13C-NMR and ESIMS spectroscopic data. Then, the transformed products (1-14) were isolated and identified as Rk3, Rh4, 20 (R)-Rh1, 20 (S)-Protopanaxatriol, C-K, 20 (R)-Rg3, 20 (S)-Rg3, 20 (S)-Rg2, 20 (R)-R2, Rk1, Rg5, 20 (S)-R2, 20 (R)-Rg2, and 20 (S)-I, respectively. In addition, all transformed products (1-14) were tested for their antimicrobial activity. Among them, compounds 5 (C-K) and 7 [20 (S)-Rg3] showed moderate antimicrobial activities against Staphylococcus aureus and Candida albicans with MIC values of 6.25, 1.25 μg/mL and 1.25, 25 μg/mL, respectively. This study lays the foundation for production of rare ginsenosides.

Rare ginsenosides: A unique perspective of ginseng research

BACKGROUND

Rare ginsenosides (Rg3, Rh2, C-K, etc.) refer to a group of dammarane triterpenoids that exist in low natural abundance, mostly produced by deglycosylation or side chain modification via physicochemical processing or metabolic transformation in gut, and last but not least, exhibited potent biological activity comparing to the primary ginsenosides, which lead to a high concern in both the research and development of ginseng and ginsenoside-related nutraceutical and natural products. Nevertheless, a comprehensive review on these promising compounds is not available yet.

AIM OF REVIEW

In this review, recent advances of Rare ginsenosides (RGs) were summarized dealing with the structurally diverse characteristics, traditional usage, drug discovery situation, clinical application, pharmacological effects and the underlying mechanisms, structure-activity relationship, toxicity, the stereochemistry properties, and production strategies.

KEY SCIENTIFIC CONCEPTS OF REVIEW

A total of 144 RGs with diverse skeletons and bioactivities were isolated from Panax species. RGs acted as natural ligands on some specific receptors, such as bile acid receptors, steroid hormone receptors, and adenosine diphosphate (ADP) receptors. The RGs showed promising bioactivities including immunoregulatory and adaptogen-like effect, anti-aging effect, anti-tumor effect, as well as their effects on cardiovascular and cerebrovascular system, central nervous system, obesity and diabetes, and interaction with gut microbiota. Clinical trials indicated the potential of RGs, while high quality data remains inadequate, and no obvious side effects was found. The stereochemistry properties induced by deglycosylation at C (20) were also addressed including pharmacodynamics behaviors, together with the state-of-art analytical strategies for the identification of saponin stereoisomers. Finally, the batch preparation of targeted RGs by designated strategies including heating or acid/ alkaline-assisted processes, and enzymatic biotransformation and biosynthesis were discussed. Hopefully, the present review can provide more clues for the extensive understanding and future in-depth research and development of RGs, originated from the worldwide well recognized ginseng plants.

Study on the Biotransformation and Activities of Astragalosides from Astragali Radix In Vitro and In Vivo

Astragalosides (AGs), as one of the main active ingredients in Astragali Radix (AR), have a series of biological activities. Previous studies have only qualitatively identified the metabolites of AGs in AR, resulting in a lack of quantification. In the present study, the original material was selected from 12 origins based on the levels of 4 AGs by high-performance liquid chromatography (HPLC). The prototype components and metabolites of total AGs (TAGs) in feces, urine, and plasma samples of rats were thoroughly screened and characterized by ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC-HRMS). The fermentation reaction and metabolites were verified by human fecal TAG fermentation in vitro. The metabolites of AG I, II, and IV transformed by human feces at different times were identified using UHPLC-HRMS, and the partial metabolites were quantified by HPLC. Furthermore, the anti-inflammatory and antioxidant activities of the metabolites were evaluated based on 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells in vitro. In total, 13 AGs and 170 metabolites were identified in TAGs as well as in the plasma, urine, and feces of Sprague-Dawley (SD) rats by UHPLC-HRMS, including 28, 36, and 170 metabolites in the plasma, urine, and feces, respectively. The metabolites included the products of deglycosylation, demethylation, hydroxylation, glucuronidation, sulfation, and cysteine-binding reactions. Moreover, the TAG fermentation results in vitro showed great similarity. The human fecal incubation experiments for AG I, II, and IV demonstrated that the metabolic reaction of TAGs mainly occurred in intestinal feces and that deglycosylation, demethylation, and hydroxylation were the main pathways of their metabolism. HPLC quantitative analysis of the transformation solution at different time points showed that AGs were transformed into secondary glycosides [cycloastragenol-6-glucoside (CAG-6-glucoside)] and aglycones [cycloastragenol (CAG)] through a deglycosylation reaction. Analysis of the pharmacological activity showed that the anti-inflammatory and antioxidant activities of the metabolites were associated with the levels of the corresponding aglycones. Further, metabolic profiles of the TAGs were constructed. Overall, this study revealed the metabolic process of AGs in the intestine, providing guidance for the metabolism and pharmacological effects of other saponins.

Characterization of Ginsenosides from the Root of Panax ginseng by Integrating Untargeted Metabolites Using UPLC-Triple TOF-MS

To compare the chemical distinctions of Panax ginseng Meyer in different growth environments and explore the effects of growth-environment factors on P. ginseng growth, an ultra-performance liquid chromatography-tandem triple quadrupole time-of-flight mass spectrometry (UPLC-Triple-TOF-MS/MS) was used to characterize the ginsenosides obtained by ultrasonic extraction from P. ginseng grown in different growing environments. Sixty-three ginsenosides were used as reference standards for accurate qualitative analysis. Cluster analysis was used to analyze the differences in main components and clarified the influence of growth environment factors on P. ginseng compounds. A total of 312 ginsenosides were identified in four types of P. ginseng, among which 75 were potential new ginsenosides. The number of ginsenosides in L15 was the highest, and the number of ginsenosides in the other three groups was similar, but it was a great difference in specie of ginsenosides. The study confirmed that different growing environments had a great influence on the constituents of P. ginseng, and provided a new breakthrough for the further study of the potential compounds in P. ginseng.

20(22)Z and 20(22)E Dammarane Saponins From the Roots of Panax pseudoginseng Wall

Panax pseudoginseng Wall. is famous as a traditional Vietnamese medicinal plant used to promote health and aid in cancer treatment. From the roots of this plant, 1 new (1) and 4 known (2-5) Δ20(22)-dammarane-type triterpenoid glycosides were isolated by various chromatographic methods. Their chemical structures were determined as 3β,6α,12β-trihydroxydammarane-( Z)-20(22),24-diene 6 -O-β-D-glucopyranoside (1), 3β,6α,12β-trihydroxy-dammar-( E)-20(22),25-diene 6 -O-β-D-glucopyranoside (2, ginsenoside Rh4), ginsenoside Rg5 (3), 3β,12β-dihydroxydammarane-( E)-20(22),24-diene 6 -O-β-D-xylopyranosyl-(1→2)-β-D-glucopyranoside (4), and 3β,12β-dihydroxydammarane-( E)-20(22),24-diene 6 -O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside (5). The E/ Z-Δ20(22) configurations in the dammarane compounds were further evidenced by 1D and 2D NMR data.

Highly Regioselective Biotransformation of Protopanaxadiol-type and Protopanaxatriol-type Ginsenosides in the Underground Parts of Panax notoginseng to 18 Minor Ginsenosides by Talaromyces flavus

The transformation of major ginsenosides to minor ginsenosides by microorganisms was considered to be an environmentally friendly method. Compared with GRAS (generally recognized as safe) strains, non-food-grade microorganisms could transform polar ginsenosides to various minor ginsenosides. In this study, Talaromyces flavus screened from the P. notoginseng rhizosphere was capable of transforming PPD-type and PPT-type ginsenosides in the underground parts of P. notoginseng to 18 minor ginsenosides. The transformation reactions invovled deglycosylation, epimerization, and dehydration. To the best of our knowledge, this transformation characteristic of T. flavus was first reported in fungi. Its crude enzyme can efficiently hydrolyze the outer glucose linked to C-20 and C-3 in major ginsenosides Rb₁, Rb₂, Rb₃, Rc, Rd, and 20(S)-Rg₃ within 48 h. The transformation of major ginsenosides to minor ginsenosides by T. flavus will help raise the functional and economic value of P. notoginseng.

Gut Microbiota: Therapeutic Targets of Ginseng Against Multiple Disorders and Ginsenoside Transformation

Panax ginseng, as the king of Chinese herb, has significant therapeutic effects on obesity, type 2 diabetes mellitus, fatty liver disease, colitis, diarrhea, and many other diseases. This review systematically summarized recent findings, which show that ginseng plays its role by regulating gut microbiota diversity, and gut microbiota could also regulate the transformation of ginsenosides. We conclude the characteristics of ginseng in regulating gut microbiota, as the potential targets to prevent and treat metabolic diseases, colitis, neurological diseases, cancer, and other diseases. Ginseng treatment can increase some probiotics such as Bifidobacterium, Bacteroides, Verrucomicrobia, Akkermansia, and reduce pathogenic bacteria such as Deferribacters, Lactobacillus, Helicobacter against various diseases. Meanwhile, Bacteroides, Eubacterium, and Bifidobacterium were found to be the key bacteria for ginsenoside transformation in vivo. Overall, ginseng can regulate gut microbiome diversity, further affect the synthesis of secondary metabolites, as well as promote the transformation of ginsenosides for improving the absorptivity of ginsenosides. This review can provide better insight into the interaction of ginseng with gut microbiota in multiple disorders and ginsenoside transformation.

Cordyceps sinensis-mediated biotransformation of notoginsenoside R1 into 25-OH-20(S/R)-R2 with elevated cardioprotective effect against DOX-induced cell injury

Notoginsenoside R1 is a dammarane saponin in Panax notoginseng with promising cardioprotective effects. The bioactivity–structure relationship of such saponins suggested that the presence of a hydroxyl group at C25 could elevate its performance. To fulfill that goal, bioconversion of notoginsenoside R1 was mediated by a biocatalytic system of Cordyceps sinensis that had successfully produced multiple 25-OH derivatives from ginsenoside Re and Rg1. The major metabolic products of notoginsenoside R1 were identified as 25-OH-20(S/R)-R2 via the techniques of HRMS, ¹³C-NMR, ¹H-NMR, HSQC and HMBC. Time-course experiments were designed to monitor the reaction process, establishing a biocatalytic pathway of “R1→20(S/R)-R2→25-OH-20(S/R)-R2”. The bioconversion rate of these 25-OH derivatives added up to 69.87% which greatly precedes the previous report. Afterwards, the effect of these biocatalytic products against doxorubicin-induced cardiotoxicity was evaluated, indicating a significant increase in efficacy after the hydration of the C24–C25 double bond on the dammarane skeleton. In conclusion, the biocatalytic system employed in this paper is able to harvest 25-OH-20(S/R)-R2 in high yield from notoginsenoside R1, which will provide lead compounds or drug candidates to alleviate myocardial injury caused by doxorubicin.

The biocatalytic system in this paper preferably yielded 25-OH notoginsenoside R2 from R1 in a regioselective manner. Such a process significantly elevated the effects of these 25-OH derivatives against DOX-induced cardiomyocyte injury.

Highly regioselective biotransformation of ginsenoside Rg1 to 25-OH derivatives of 20(S/R)-Rh1 by Cordyceps Sinensis

25-OH ginsenosides are potent and rare prodrugs in natural sources. However current strategies for such modification always end up in undesirable side products and unsatisfied yield that hinders them from further applications. Herein, ginsenoside Rg1 was thoroughly converted into 20(S/R)-Rh1 and 25-OH-20(S/R)-Rh1 by Cordyceps Sinensis in an optimum medium. The chemical correctness of either 25-OH-20(S/R)-Rh1 epimers was validated by LC-IT-TOF-MSn and ¹³C NMR spectrometry. The biocatalytic pathway was established as Rg1 → 20(S/R)-Rh1 → 25-OH-20(S/R)-Rh1. The molar bioconversion rate for total 25-OH-20(S/R)-Rh1 was calculated to be 82.5%, of which S-configuration accounted for 43.2% while R-configuration 39.3%. These two 25-OH derivatives are direct hydration products from 20(S/R)-Rh1 without other side metabolites, suggesting this is a highly regioselective process. In conclusion, this biocatalytic system could be harnessed to facilitate the preparation of diversified 25-OH ginsenosides with high yields of the target compound and simple chemical background in the reaction mixture.

New dammarane-type triterpenoid saponins from Panax notoginseng saponins

BACKGROUND

Panax notoginseng saponin (PNS) is the extraction from the roots and rhizomes of Panax notoginseng (Burk.) F. H. Chen. PNS is the main bioactive component of Xuesaitong, Xueshuantong, and other Chinese patent medicines, which are all bestselling prescriptions in China to treat cardiocerebrovascular diseases. Notoginsenoside R1 and ginsenoside Rg1, Rd, Re, and Rb1 are the principal effective constituents of PNS, but a systematic research on the rare saponin compositions has not been conducted.

OBJECTIVE

The objective of this study was to conduct a systematic chemical study on PNS and establish the HPLC fingerprint of PNS to provide scientific evidence in quality control. In addition, the cytotoxicity of the new compounds was tested.

METHODS

Pure saponins from PNS were isolated by means of many chromatographic methods, and their structures were determined by extensive analyses of NMR and HR-ESI-MS studies. The fingerprint was established by HPLC-UV method. The cytotoxicity of the compounds was tested by 3-(4,5-dimethylthiazol-2-yl)-2,5 -diphenyltetrazolium bromide assay.

RESULTS AND CONCLUSION

Three new triterpenoid saponins (1-3) together with 25 known rare saponins (4-28) were isolated from PNS, except for the five main compounds (notoginsenoside R1 and ginsenoside Rg1, Rd, Re, and Rb1). In addition, the HPLC fingerprint of PNS was established, and the peaks of the isolated compounds were marked. The study of chemical constituents and fingerprint was useful for the quality control of PNS. The study on antitumor activities showed that new Compound 2 exhibited significant inhibitory activity against the tested cell lines.

Highly regioselective bioconversion of ginsenoside Re into 20(S/R)-Rf2 by an optimized culture of Cordyceps sinensis

Highly regioselective hydration of the C24–C25 double bond is discovered during the bioconversion of ginsenoside Re by Cordyceps sinensis.

Advances in the chemistry, pharmacological diversity, and metabolism of 20(R)-ginseng saponins

Ginseng has been used as a popular herbal medicine in East Asia for at least two millennia. However, 20(R)-ginseng saponins, one class of important rare ginsenosides, are rare in natural products. 20(R)-ginseng saponins are generally prepared by chemical epimerization and microbial transformation from 20(S)-isomers. The C20 configuration of 20(R)-ginseng saponins are usually determined by 13C NMR and X-ray single-crystal diffraction. 20(R)-ginseng saponins have antitumor, antioxidative, antifatigue, neuroprotective, and osteoclastogenesis inhibitory effects, among others. Owing to the chemical structure and pharmacological and stereoselective properties, 20(R)-ginseng saponins have attracted a great deal of attention in recent years. In this study, the discovery, identification, chemical epimerization, microbial transformation, pharmacological activities, and metabolism of 20(R)-ginseng saponins are summarized.

Genome sequencing of strain Cellulosimicrobium sp. TH-20 with ginseng biotransformation ability

Biotransformation for increasing the pharmaceutical effect of ginsenosides is getting more and more attractions. Strain Cellulosimicrobium sp. TH-20 isolated from ginseng soil samples was identified to produce enzymes contributing to its excellent biotransformation activity against ginsenosides, the main active components of ginseng. Based on phylogenetic tree and homology analysis, the strain can be designated as Cellulosimicrobium sp. Genome sequencing was performed using the Illumina Miseq to explore the functional genes involved in ginsenoside transformation. The draft genome of Cellulosimicrobium sp. TH-20 encoded 3450 open reading frames, 51 tRNA, and 9 rRNA. All ORFs were annotated using NCBI BLAST with non-redundant proteins, Gene Ontology, Cluster of Orthologous Gene, and Kyoto Encyclopedia of Genes and Genomes databases. A total of 11 genes were selected based on the functional annotation analysis. These genes are relevant to ginsenoside biotransformation, including 6 for beta-glucosidase, 1 for alpha-N-arabinofuranosidase, 1 for alpha-1,6-glucosidase, 1 for endo-1,4-beta-xylanase, 1 for alpha-L-arabinofuranosidase, and 1 for beta-galactosidase. These glycosidases were predicted to catalyze the hydrolysis of sugar moieties attached to the aglycon of ginsenosides and led to the transformation of PPD-type and PPT-type ginsenosides.

Minor dehydrogenated and cleavaged dammarane-type saponins from the steamed roots of Panax notoginseng

Nine new minor dehydrogenated and cleavaged dammarane-type triterpenoid saponins, namely notoginsenosides ST6-ST14 (1-9) were isolated from the steamed roots of Panax notoginseng, together with 14 known ones. Among them, 5-7 and 21-22 were protopanaxadiol type and the left 18 compounds, including 1-4, 8-20, and 23 were protopanaxatriol type saponins. Their structures were identified by extensive analysis of MS, 1D and 2D NMR spectra, and acidic hydrolysis. Resulted from the side chain cleavage, the new saponins 1 and 2 featured in a ketone group at C-25, and 3-5 had an aldehyde unit at C-23. The known saponins 12, 16 and 18 displayed the enhancing potential of neurite outgrowth of NGF-mediated PC12 cells at a concentration of 10 μM, while 20 exhibited acetyl cholinesterase inhibitory activity, with IC50 value of 13.97 μM.

Efficacy and Safety of Panax notoginseng Saponin Therapy for Acute Intracerebral Hemorrhage, Meta-Analysis, and Mini Review of Potential Mechanisms of Action

Intracranial/intracerebral hemorrhage (ICH) is a leading cause of death and disability in people with traumatic brain injury (TBI) and stroke. No proven drug is available for ICH. Panax notoginseng (total saponin extraction, PNS) is one of the most valuable herb medicines for stroke and cerebralvascular disorders in China. We searched for randomized controlled clinical trials (RCTs) involving PNS injection to treat cerebral hemorrhage for meta-analysis from various databases including the Chinese Stroke Trials Register, the trials register of the Cochrane Complementary Medicine Field, the Cochrane Central Register of Controlled Trials, MEDLINE, Chinese BioMedical disk, and China Doctorate/Master Dissertations Databases. The quality of the eligible trials was assessed by Jadad’s scale. Twenty (20) of the 24 identified randomized controlled trials matched the inclusive criteria including 984 ICH patients with PNS injection and 907 ICH patients with current treatment (CT). Compared to the CT groups, PNS-treated patients showed better outcomes in the effectiveness rate (ER), neurological deficit score, intracranial hematoma volume, intracerebral edema volume, Barthel index, the number of patients died, and incidence of adverse events. Conclusion: PNS injection is superior to CT for acute ICH. A review of the literature shows that PNS may exert multiple protective mechanisms against ICH-induced brain damage including hemostasis, anti-coagulation, anti-thromboembolism, cerebral vasodilation, invigorated blood dynamics, anti-inflammation, antioxidation, and anti-hyperglycemic effects. Since vitamin C and other brain cell activators (BCA) that are not considered common practice were also used as parts of the CT in several trials, potential PNS and BCA interactions could exist that may have made the effect of PNS therapy less or more impressive than by PNS therapy alone. Future PNS trials with and without the inclusion of such controversial BCAs as part of the CT could clarify the situation. As PNS has a long clinical track record in Asia, it could potentially become a therapy option to treat ICH in the US and Europe. Further clinical trials with better experimental design could determine the long-term effects of PNS treatment for TBI and stroke.

Synthesis and anti-cancer cell activity of pseudo-ginsenoside Rh2

β-d-Glucopyranoside,(3β,12β,20E)-12,25-dihydroxydammar-20(22)-en-3-yl (pseudo-ginsenoside Rh2) and its 20Z-isomer were synthesized from ginsenoside Rh2 under a mild condition, via a simple three-step called acetylation, elimination-addition and saponification. In addition, their activities were evaluated by eight different human tumor cells, compared with ginsenoside Rh2 group. Results indicated that the reaction in the side chain might greatly enhance the anti-proliferative activity of ginsenosides.

Complete (1)H-NMR and (13)C-NMR spectral analysis of the pairs of 20(S) and 20(R) ginsenosides

BACKGROUND

Ginsenosides, the major ingredients of Panax ginseng, have been studied for many decades in Asian countries as a result of their wide range of pharmacological properties. The less polar ginsenosides, with one or two sugar residues, are not present in nature and are produced during manufacturing processes by methods such as heating, steaming, acid hydrolysis, and enzyme reactions. (1)H-NMR and (13)C-NMR spectroscopic data for the identification of the less polar ginsenosides are often unavailable or incomplete.

METHODS

We isolated 21 compounds, including 10 pairs of 20(S) and 20(R) less polar ginsenosides (1-20), and an oleanane-type triterpene (21) from a processed ginseng preparation and obtained complete (1)H-NMR and (13)C-NMR spectroscopic data for the following compounds, referred to as compounds 1-21 for rapid identification: 20(S)-ginsenosides Rh2 (1), 20(R)-Rh2 (2), 20(S)-Rg3 (3), 20(R)-Rg3 (4), 6'-O-acetyl-20(S)-Rh2 [20(S)-AcetylRh2] (5), 20(R)-AcetylRh2 (6), 25-hydroxy-20(S)-Rh2 (7), 25-hydroxy-20(S)-Rh2 (8), 20(S)-Rh1 (9), 20(R)-Rh1 (10), 20(S)-Rg2 (11), 20(R)-Rg2 (12), 25-hydroxy-20(S)-Rh1 (13), 25-hydroxy-20(R)-Rh1 (14), 20(S)-AcetylRg2 (15), 20(R)-AcetylRg2 (16), Rh4 (17), Rg5 (18), Rk1 (19), 25-hydroxy-Rh4 (20), and oleanolic acid 28-O-β-D-glucopyranoside (21).

Bioactivity and bioavailability of ginsenosides are dependent on the glycosidase activities of the A/J mouse intestinal microbiome defined by pyrosequencing

PURPOSE

To investigate the ability of bacteria in the intestinal microbiome to convert naturally occurring primary ginsenosides in red ginseng extract to active secondary ginsenosides.

METHODS

Anti-proliferative ginsenoside activity was tested using mouse lung cancer LM1 cells. Permeabilities were evaluated in Caco-2 cell monolayers. Systemic exposure of secondary ginsenosides was determined in A/J mice. 16S rRNA gene pyrosequencing was used to determine membership and abundance of bacteria in intestinal microbiome.

RESULTS

Secondary ginsenoside C-K exhibited higher anti-proliferative activity and permeability than primary ginsenosides. Significant amounts of secondary ginsenosides (F2 and C-K) were found in blood of A/J mice following oral administration of primary ginsenoside Rb1. Because mammalian cells did not hydrolyze ginsenoside, we determined the ability of bacteria to hydrolyze ginsenosides and found that Rb1 underwent stepwise hydrolysis to Rd, F2, and then C-K. Formation of F2 from Rd was the rate-limiting step in the biotransformation of Rb1 to C-K.

CONCLUSION

Conversion to F2 is the rate-limiting step in bioactivation of primary ginsenosides by A/J mouse intestinal microbiome, whose characterization reveals the presence of certain bacterial families capable of enabling the formation of F2 and C-K in vivo.

Two novel hydroperoxylated products of 20(S)-protopanaxadiol produced by Mucor racemosus and their cytotoxic activities against human prostate cancer cells

Microbial transformation of 20(S)-protopanaxadiol (1) by Mucor racemosus AS 3.205 yielded two novel hydroperoxylated metabolites and three known hydroxylated metabolites. The structures of the metabolites were identified as 26-hydroxyl-20(S)-protopanaxadiol (2), 23,24-en-25-hydroxyl-20(S)-protopanaxadiol (3), 25,26-en-24(R)-hydroperoxyl-20(S)-protopanaxadiol (4), 23,24-en-25-hydroperoxyl-20(S)-protopanaxadiol (5), and 25-hydroxyl-20(S)-protopanaxadiol (6). 4 and 5 are new compounds. Metabolites 2, 4, and 5 showed the more potent inhibitory effects against DU-145 and PC-3 cell lines than the substrate.

Ginsenosidases and the pathogenicity of Pythium irregulare

American ginseng (Panax quinquefolius L.) produces triterpenoid saponins, ginsenosides, that possess mild fungitoxic activity toward some common ginseng leaf pathogens. However, numerous oomycete root pathogens of ginseng, most notably Pythium irregulare Buisman, are able to partially deglycosylate 20 (S)-protopanaxadiol ginsenosides Rb1, Rd and gypenoside XVII via extracellular glycosidases, leading to a common product, ginsenoside F2. Conversion of the common 20 (S)-protopanaxadiols into F2 requires both β (1→6) and β (1→2) glucosidase activity. In the present study, the ability of nine distinct isolates of P. irregulare, as well as a P. ultimum Trow isolate and two isolates of Trichoderma hamatum (Bonord.) Bainier, to deglycosylate 20 (S)-protopanaxadiols, in vitro was examined. The pathogenicity of each isolate was also examined by scoring the severity of disease symptoms caused by each in separate inoculations of one- and two-year old ginseng seedlings. Disease severity was scored using a disease severity index, as well as by taking F(v)/F(m) measurements of leaves during a 14-day infection period. Based on these measurements, it was concluded that (1) the use of direct F(v)/F(m) measurements correlates strongly with observations of disease severity (R(2)=0.79), and that (2) the pathogenicity of P. irregulare isolates correlates with their ability to deglycosylate ginsenosides (R(2)=0.57). These results further support the hypothesis that the pathogenicity of P. irregulare on ginseng roots is dependent, in part, on the ability of this organism to deglycosylate ginsenosides.

Ginsenosides from American ginseng: chemical and pharmacological diversity

Ginseng occupies a prominent position in the list of best-selling natural products in the world. Compared to the long history of use and widespread research on Asian ginseng, the study of American ginseng is relatively limited. In the past decade, some promising advances have been achieved in understanding the chemistry, pharmacology and structure-function relationship of American ginseng. To date, there is no systematic review of American ginseng. In this review, the different structures of the ginsenosides in American ginseng are described, including naturally occurring compounds and those resulting from steaming or biotransformation. Preclinical and clinical studies published in the past decade are also discussed. Highlighted are the chemical and pharmacological diversity and potential structural-activity relationship of ginsenosides. The goal is that this article is a useful reference to chemists and biologists researching American ginseng, and will open the door to agents in drug discovery.

Antihepatocarcinoma activity of lactic acid bacteria fermented Panax notoginseng

Panax notoginseng was used as the medium for lactic acid bacteria fermentation to manufacture product with antihepatocarcinoma activity. The fermentation broth prepared in a 250 mL Erlenmeyer flask was found to possess antiproliferation activity against hepatoma Hep3B cells. At the dosage of 500 microg/mL, the viability of hepatoma Hep3B cells was approximately 2.2%. When the fermentation was scaled up to a 6.6 L fermenter, it was found that the fermentation broth produced at 37 degrees C for 2 days showed the highest antihepatoma activity. Animal study revealed that when Hep3B implanted SCID mice were treated with 1000 mg/kg BW/day of the fermentation broth, tumor volume and tumor weight were reduced approximately 60% as compared to the negative control group. HPLC analyses showed that saponins in P. notoginseng including notoginsenoside R(1) and ginsenosides Rg(1), Rb(1), Rd, and Rh(4) decreased, but ginsenosides Rh(1) and Rg(3) increased during fermentation. LC-MS/MS revealed that the minor saponins ginsenoside F(1), protopanaxatriol, and notoginseng R(2) also exist in the fermentation product. It appears that ginsenoside Rg(3), ginsenoside Rh(1), and protopanaxatriol are possibly responsible for the enhanced antihepatocarcinoma activity of the P. notoginseng fermentation broth.

Current evaluation of the millennium phytomedicine- ginseng (II): Collected chemical entities, modern pharmacology, and clinical applications emanated from traditional Chinese medicine

This review, a sequel to part 1 in the series, collects about 107 chemical entities separated from the roots, leaves and flower buds of Panax ginseng, quinquefolius and notoginseng, and categorizes these entities into about 18 groups based on their structural similarity. The bioactivities of these chemical entities are described. The 'Yin and Yang' theory and the fundamentals of the 'five elements' applied to the traditional Chinese medicine (TCM) are concisely introduced to help readers understand how ginseng balances the dynamic equilibrium of human physiological processes from the TCM perspectives. This paper concerns the observation and experimental investigation of biological activities of ginseng used in the TCM of past and present cultures. The current biological findings of ginseng and its medical applications are narrated and critically discussed, including 1) its antihyperglycemic effect that may benefit type II diabetics; in vitro and in vivo studies demonstrated protection of ginseng on beta-cells and obese diabetic mouse models. The related clinical trial results are stated. 2) its aphrodisiac effect and cardiovascular effect that partially attribute to ginseng's bioactivity on nitric oxide (NO); 3) its cognitive effect and neuropharmacological effect that are intensively tested in various rat models using purified ginsenosides and show a hope to treat Parkinson's disease (PD); 4) its uses as an adjuvant or immunotherapeutic agent to enhance immune activity, appetite and life quality of cancer patients during their chemotherapy and radiation. Although the apoptotic effect of ginsenosides, especially Rh2, Rg3 and Compound K, on various tumor cells has been shown via different pathways, their clinical effectiveness remains to be tested. This paper also updates the antioxidant, anti-inflammatory, anti-apoptotic and immune-stimulatory activities of ginseng, its ingredients and commercial products, as well as common side effects of ginseng mainly due to its overdose, and its pharmacokinetics.

Comparative Analysis of Microbial and Rat Metabolism of the Total Saponins from Panax notoginseng by HPLC-ESI-MS/MS

The total saponins extracted from the roots of Panax notoginseng have been regarded as the principal components manifesting the pharmacological activities of the drug. In order to compare the similarities and differences of microbial and mammalian metabolism of PNS, liquid chromatography coupled with mass spectrometry and tandem mass spectrometry has been applied to investigate the constituents and metabolites of the microbial transformations by three fungi Absidia coerulea, Acremonium strictum, and Curvularia lunata, and metabolism in rats. A total of thirty-seven peaks were detected and thirty-one peaks were identified by comparing the retention times and MS spectra with those of reference compounds and literature data. Twenty-eight peaks were found both in microbial and rat metabolism samples of PNS. Their structures were identified by comparison of the retention times and MS spectra with those of reference compounds. A number of isomers were identified after the metabolism.