Four new ginsenosides from red ginseng with inhibitory activity on melanogenesis in melanoma cells

Phytochemistry of Red Ginseng, a Steam-Processed Panax ginseng

Asian ginseng, the root of Panax ginseng C.A. Meyer, occupies a prominent position in the list of best-selling natural products in the world. There are two major types of ginseng roots: white ginseng and red ginseng, each with numerous preparations. White ginseng is prepared by air-drying fresh Asian ginseng roots after harvest. Red ginseng is prepared by steaming roots in controlled conditions using fresh or raw Asian ginseng. Red ginseng is commonly used in Asian countries due to its unique chemical profile, different therapeutic efficacy, and increased stability. Compared with the widespread research on white ginseng, the study of red ginseng is relatively limited. In this paper, after a botanical feature description, the structures of different types of constituents in red ginseng are systematically described, including naturally occurring compounds and those resulting from the steam processing. In red ginseng phytochemical studies, the number of published reports on ginsenosides is significantly higher than that for other constituents. Up to now, 57 ginsenosides have been isolated and characterized in red ginseng. The structural transformation pathways during steaming have been summarized. In comparison with white ginseng, red ginseng also contains other constituents, including polyacetylenes, Maillard reaction products, other types of glycosides, lignans, amino acids, fatty acids, and polysaccharides, which have also been presented. Appropriate analytical methods are necessary for differentiating between unprocessed white ginseng and processed red ginseng. Specific marker compounds and chemical profiles have been used to discriminate red ginseng from white ginseng and adulterated commercial products. Additionally, a brief phytochemical profile comparison has been made between white ginseng and black ginseng, and the latter is another type of processed ginseng prepared from white or red ginseng by steaming several times. In conclusion, to ensure the safe and effective use of red ginseng, phytochemical and analytical studies of its constituents are necessary and even crucial.

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.

Bioactive Steroids Bearing Oxirane Ring

This review explores the biological activity and structural diversity of steroids and related isoprenoid lipids, with a particular focus on compounds containing an oxirane ring. These natural compounds are derived from fungi, fungal endophytes, as well as extracts of plants, algae, and marine invertebrates. To evaluate their biological activity, an extensive examination of refereed literature sources was conducted, including in vivo and in vitro studies and the utilization of the QSAR method. Notable properties observed among these compounds include strong anti-inflammatory, antineoplastic, antiproliferative, anti-hypercholesterolemic, antiparkinsonian, diuretic, anti-eczematic, anti-psoriatic, and various other activities. Throughout this review, 3D graphs illustrating the activity of individual steroids are presented, accompanied by images of selected terrestrial or marine organisms. Furthermore, this review provides explanations for specific types of biological activity associated with these compounds. The data presented in this review are of scientific interest to the academic community and carry practical implications in the fields of pharmacology and medicine. By analyzing the biological activity and structural diversity of steroids and related isoprenoid lipids, this review offers valuable insights that contribute to both theoretical understanding and applied research. This review draws upon data from various authors to compile information on the biological activity of natural steroids containing an oxirane ring.

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.

Saponins of ginseng products: a review of their transformation in processing

The primary processed product of Panax ginseng C.A. Meyer (P. ginseng) is red ginseng. As technology advances, new products of red ginseng have arisen. Red ginseng products, e.g., traditional red ginseng, sun ginseng, black ginseng, fermented red ginseng, and puffed red ginseng, are commonly used in herbal medicine. Ginsenosides are the major secondary metabolites of P. ginseng. The constituents of P. ginseng are significantly changed during processing, and several pharmacological activities of red ginseng products are dramatically increased compared to white ginseng. In this paper, we aimed to review the ginsenosides and pharmacological activities of various red ginseng products, the transformation law of ginsenosides in processing, and some clinical trials of red ginseng products. This article will help to highlight the diverse pharmacological properties of red ginseng products and aid in the future development of red ginseng industrialization.

Shengmai san-derived compound prescriptions: A review on chemical constituents, pharmacokinetic studies, quality control, and pharmacological properties

BACKGROUND

Shengmai San Formula (SMS), composed of Ginseng Radix et Rhizoma, Ophiopogon Radix and Schisandra chinensis Fructus, was a famous formula in Tradition Chinese Medicine (TCM). With the expansion of clinical applications, SMS was developed to different dosage forms, including Shengmai Yin Oral liquid (SMY), Shengmai Capsule (SMC), Shengmai Granule (SMG), Shengmai Injection (SMI) and Dengzhan Shengmai Capsule (DZSMC). These above SMS-derived compound prescriptions (SSCPs) play an important role in the clinical treatment. This review is aimed to providing a comprehensive perspective of SSCP.

METHODS

The relevant literatures were collected from classical TCM books and a variety of databases, including PubMed, Google Scholar, Science Direct, Springer Link, Web of Science, China National Knowledge Infrastructure, and Wanfang Data.

RESULTS

The chemical constituents of SSCPs, arrived from the individual medicinal materials including Ginseng Radix et Rhizoma, Ophiopogon Radix, Schisandra chinensis Fructus, Erigerontis Herba, were firstly summarized respectively. Then the pharmacokinetics studies, quality control, and pharmacological properties of SSCPs were all reviewed. The active compounds, pharmacokinetics characterizes, quality control markers, the effects and mechanisms of pharmacology of the different dosage forms of SSCPs were summarized. Furthermore, the research deficiencies of SSCPs and an innovative research paradigm for Chinese materia medica (CMM) formula were proposed.

CONCLUSIONS

SMS, as a famous CMM formula, has great values in drug research and in clinical treatment especially for cardiocerebrovascular diseases. This article firstly make a comprehensive and systematic review on SMS.

Plant extracellular vesicles: A novel bioactive nanoparticle for tumor therapy

Extracellular vesicles are tiny lipid bilayer-enclosed membrane particles, including apoptotic bodies, micro vesicles, and exosomes. Organisms of all life forms can secrete extracellular vesicles into their surrounding environment, which serve as important communication tools between cells and between cells and the environment, and participate in a variety of physiological processes. According to new evidence, plant extracellular vesicles play an important role in the regulation of transboundary molecules with interacting organisms. In addition to carrying signaling molecules (nucleic acids, proteins, metabolic wastes, etc.) to mediate cellular communication, plant cells External vesicles themselves can also function as functional molecules in the cellular microenvironment across cell boundaries. This review introduces the source and extraction of plant extracellular vesicles, and attempts to clarify its anti-tumor mechanism by summarizing the current research on plant extracellular vesicles for disease treatment. We speculate that the continued development of plant extracellular vesicle-based therapeutic and drug delivery platforms will benefit their clinical applications.

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.

Anti-melanogenic property of ginsenoside Rf from Panax ginseng via inhibition of CREB/MITF pathway in melanocytes and ex vivo human skin

Background

Ginsenosides of Panax ginseng are used to enhance skin health and beauty. The present study aimed to investigate the potential use of ginsenoside Rf (Rf) from Panax ginseng as a new anti-pigmentation agent.

Methods

The anti-melanogenic effects of Rf were explored. The transcriptional activity of the cyclic adenosine monophosphate (cAMP) response element binding protein (CREB) and the expression levels of tyrosinase, microphthalmia-associated transcription factor (MITF), and tyrosinase-related proteins (Tyrps) were evaluated in melanocytes and UV-irradiated ex vivo human skin.

Results

Rf significantly inhibited Forskolin (FSK) or UV-stimulated melanogenesis. Consistently, cellular tyrosinase activity and levels of MITF, tyrosinase, and Tyrps were downregulated. Furthermore, Rf suppressed MITF promoter activity, which was stimulated by FSK or CREB-regulated transcription coactivator 3 (CRTC3) overexpression. Increased CREB phosphorylation and protein kinase A (PKA) activity induced by FSK were also mitigated in the presence of Rf.

Conclusion

Rf can be used as a reliable anti-pigmentation agent, which has a scientifically confirmed and reproducible action mechanism, via inhibition of CREB/MITF pathway.

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.

Reinvestigation of Herniaria glabra L. saponins and their biological activity

Twelve undescribed triterpenoid pentacyclic glycosides, medicagenic acid (3-O-β-D-glucuronopyranosyl-28-O-{[β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)]-[α-L-rhamnopyranosyl-(1 → 3)]-4-O-acetyl-β-D-fucopyranosyl-(1→)}-2β,3β-dihydroxyolean-12-ene-23,28-dioic acid, 3-O-β-D-glucuronopyranosyl-28-O-{[α-L-rhamnopyranosyl-(1 → 2)]-[β-D-apiofuranosyl-(1 → 3)]-4-O-acetyl-β-D-fucopyranosyl-(1→)}-2β,3β-dihydroxyolean-12-ene-23,28-dioic acid, 3-O-β-D-glucuronopyranosyl-28-O-{[α-L-rhamnopyranosyl-(1 → 2)]-3,4-O-diacetyl-β-D-fucopyranosyl-(1→)}-2β,3β-dihydroxyolean-12-ene-23,28-dioic acid, 28-O-{[6-O-acetyl-β-D-glucopyranosyl-(1 → 2)]-[2-O-acetyl-α-L-rhamnopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 6)]-β-D-glucopyranosyl-(1→)}-2β,3β-dihydroxyolean-12-ene-23,28-dioic acid, 28-O-{[6-O-acetyl-β-D-glucopyranosyl-(1 → 2)]-[3-O-acetyl-α-L-rhamnopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 6)]-β-D-glucopyranosyl-(1→)}-2β,3β-dihydroxyolean-12-ene-23,28-dioic acid, 28-O-{[6-O-acetyl-β-D-glucopyranosyl-(1 → 2)]-[4-O-acetyl-α-L-rhamnopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 6)]-β-D-glucopyranosyl-(1→)}-2β,3β-dihydroxyolean-12-ene-23,28-dioic acid, 28-O-{[6-O-acetyl-β-D-glucopyranosyl-(1 → 2)]-[β-D-glucopyranosyl-(1 → 6)]-β-D-glucopyranosyl-(1→)}-2β,3β-dihydroxyolean-12-ene-23,28-dioic acid, 28-O-{[β-D-glucopyranosyl-(1 → 2)]-[β-D-glucopyranosyl-(1 → 6)]-β-D-glucopyranosyl-(1→)}-2β,3β-dihydroxyolean-12-ene-23,28-dioic acid), zanhic acid (3-O-β-D-glucuronopyranosyl-28-O-{[β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)]-[α-L-rhamnopyranosyl-(1 → 3)]-4-O-acetyl-β-D-fucopyranosyl-(1→)}2β,3β,16α-trihydroxyolean-12-ene-23,28-dioic acid, 3-O-β-D-glucuronopyranosyl-28-O-{[β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)]-β-D-fucopyranosyl-(1→)}-2β,3β,16α-trihydroxyolean-12-ene-23,28-dioic acid), 29-hydroxy-medicagenic acid (3-O-β-D-glucuronopyranosyl-28-O-{[β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)]-[α-L-rhamnopyranosyl-(1 → 3)]-4-O-acetyl-β-D-fucopyranosyl-(1→)}-2β,3β,29β-trihydroxyolean-12-ene-23,28-dioic acid) and herniaric acid (28-O-{[6-O-acetyl-β-D-glucopyranosyl-(1 → 2)]-[α-L-rhamnopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 6)]-β-D-glucopyranosyl-(1→)}-2β,3β-dihydroxyolean-18-ene-23,28-dioic acid) were isolated from the whole plant extract of Herniaria glabra L. (Caryophyllaceae), wild growing in the Ukraine. In addition, five known triterpenoid saponins; i.e. herniariasaponins 1, 4, 5, 6, and 7 were also isolated. Their structures were elucidated by HRESIMS, 1D and 2D NMR spectroscopy, as well as by comparison with the literature data. Twelve herniariasaponins, the purified crude extract, and the saponin fraction were evaluated in vitro for their xanthine oxidase, collagenase, elastase, and tyrosinase inhibitory activity. Moreover, herniariasaponins 4, 5, and 7 were screened for their cholinesterase inhibitory potential. As a result, no or low inhibition towards the mentioned enzymes was observed.

Triterpenoids

This review covers newly isolated triterpenoids that have been reported during 2015.

Advances in the Tyrosinase Inhibitors from Plant Source

Tyrosinase is a multifunctional copper-containing oxidase which catalyses the oxidation of tyrosine to produce melanin. The alteration in melanin biosynthesis occurs in many diseases. The pigment has a protecting role against skin photo-carcinogenesis, but anomalous melanin pigmentation is an aesthetic problem in human beings. Moreover, the formation of neuromelanin in human brain could contribute to the neurodegeneration associated with Parkinson's disease. Finally, tyrosinase is also responsible for undesired browning in fruits and vegetables. These topics encouraged the search for new inhibitors of this enzyme for pharmaceutical, cosmetic and foods industries. This review is to report recent trends in the discovery of tyrosinase inhibitors from plant sources, to provide a rationale for the continued study of natural tyrosinase inhibitors, and to recognise the potential therapeutic rewards associated with the identification of these agents.

Unraveling the molecular mechanisms and the potential chemopreventive/therapeutic properties of natural compounds in melanoma

Melanoma is the most fatal form of skin cancer. Current therapeutic approaches include surgical resection, chemotherapy, targeted therapy and immunotherapy. However, these treatment strategies are associated with development of drug resistance and severe side effects. In recent years, natural compounds have also been extensively studied for their anti-melanoma effects, including tumor growth inhibition, apoptosis induction, angiogenesis and metastasis suppression and cancer stem cell elimination. Moreover, a considerable number of studies reported the synergistic activity of phytochemicals and standard anti-melanoma agents, as well as the enhanced effectiveness of their synthetic derivatives and novel formulations. However, clinical data confirming these promising effects in patients are still scanty. This review emphasizes the anti-tumor mechanisms and potential application of the most studied natural products for melanoma prevention and treatment.

Ginsenosides analysis of New Zealand-grown forest Panax ginseng by LC-QTOF-MS/MS

Background

Ginsenosides are the unique and bioactive components in ginseng. Ginsenosides are affected by the growing environment and conditions. In New Zealand (NZ), Panax ginseng Meyer (P. ginseng) is grown as a secondary crop under a pine tree canopy with an open-field forest environment. There is no thorough analysis reported about NZ-grown ginseng.

Methods

Ginsenosides from NZ-grown P. ginseng in different parts (main root, fine root, rhizome, stem, and leaf) with different ages (6, 12, 13, and 14 years) were extracted by ultrasonic extraction and characterized by Liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry. Twenty-one ginsenosides in these samples were accurately quantified and relatively quantified with 13 ginsenoside standards.

Results

All compounds were separated in 40 min, and a total of 102 ginsenosides were identified by matching MS spectra data with 23 standard references or published known ginsenosides from P. ginseng. The quantitative results showed that the total content of ginsenosides in various parts of P. ginseng varied, which was not obviously dependent on age. In the underground parts, the 13-year-old ginseng root contained more abundant ginsenosides among tested ginseng samples, whereas in the aboveground parts, the greatest amount of ginsenosides was from the 14-year-old sample. In addition, the amount of ginsenosides is higher in the leaf and fine root and much lower in the stem than in the other parts of P. ginseng.

Conclusion

This study provides the first-ever comprehensive report on NZ-grown wild simulated P. ginseng.

Six new dammarane-type triterpene saponins from Panax ginseng flower buds and their cytotoxicity

Background

Panax ginseng has been used for a variety of medical purposes in eastern countries for more than two thousand years. From the extensive experiences accumulated in its long medication use history and the substantial strong evidence in modern research studies, we know that ginseng has various pharmacological activities, such as antitumor, antidiabetic, antioxidant, and cardiovascular system–protective effects. The active chemical constituents of ginseng, ginsenosides, are rich in structural diversity and exhibit a wide range of biological activities.

Methods

Ginsenoside constituents from P. ginseng flower buds were isolated and purified by various chromatographic methods, and their structures were identified by spectroscopic analysis and comparison with the reported data. The 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H- tetrazolium bromide method was used to test their cytotoxic effects on three human cancer cell lines.

Results

Six ginsenosides, namely 6'–malonyl formyl ginsenoside F₁ (1), 3β–acetoxyl ginsenoside F₁ (2), ginsenoside Rh₂₄ (6), ginsenoside Rh₂₅ (7), 7β–hydroxyl ginsenoside Rd (8) and ginsenoside Rh₂₆ (10) were isolated and elucidated as new compounds, together with four known compounds (3–5 and 9). In addition, the cytotoxicity of these isolated compounds was shown as half inhibitory concentration values, a tentative structure–activity relationship was also discussed based on the results of our bioassay.

Conclusion

The study of chemical constituents was useful for the quality control of P. ginseng flower buds. The study on antitumor activities showed that new Compound 1 exhibited moderate cytotoxic activities against HL-60, MGC80-3 and Hep-G2 with half inhibitory concentration values of 16.74, 29.51 and 20.48 μM, respectively.

Development and validation of a UFLC-MS/MS method for simultaneous quantification of sixty-six saponins and their six aglycones: Application to comparative analysis of red ginseng and white ginseng

A new and sensitive ultra fast liquid chromatography coupled with electrospray ionization triple quadrupole tandem mass spectrometry (UFLC-MS/MS) method was developed to evaluate the quality of Red ginseng (RG) and to find out its chemical markers by comparing with multi-batches of RG and white ginseng (WG). This innovative method could quantify sixty-six saponins and their six aglycones including 10 pairs of 20(S) and 20(R) epimers within 35 min simultaneously. All compounds could be determined in individual multiple-reaction monitoring channel without interference, and the optimized method was rapid, accurate, precise, reproducible and efficient. Using the orthogonal partial least squared discriminant analysis, ginsenosides Rg₅, Rh₄, Rk₁, Rs₄, F₄, and 20(S)-Rg₃ were found to be the characteristic components of RG, the six compounds should be suggested as quality control markers to distinguish RG from WG. These findings will be significant for standardizing the processing procedures of RG and ensuring the consistent quality, as well as consequently the efficacy of RG in clinical applications. Results will be helpful in providing crucial chemical profiles of RG.

Polyacetylenic Oleanane-Type Triterpene Saponins from the Roots of Panax japonicus

Three new polyacetylenic oleanane-type triterpenoids, baisanqisaponins A-C (1-3), and one new oleanane-type triterpenoid, chikusetsusaponin-V ethyl ester (4), together with 19 known compounds (5-23), were isolated from the roots of Panax japonicus. The structures were elucidated on the basis of spectroscopic analyses and chemical methods. Compounds 1-3 feature a rare panaxytriol group containing a polyacetylene on the saponin skeleton. Neuroprotective activity was evaluated for compounds 1-17, and angiotensin II-induced vascular smooth muscle cell proliferation inhibition was tested for compounds 5-7 and 10-12.

Antimelanogenesis Activity of Hydrolyzed Ginseng Extract (GINST) via Inhibition of JNK Mitogen-activated Protein Kinase in B16F10 Cells

GINST is a hydrolyzed ginseng extract produced by an in vitro process that imitates the metabolic function of bacteria in the human digestive track and has approved by the Ministry of Food and Drug Safety of Korea for the management of postprandial hyperglycemia. Additionally, GINST has been reported to have other physiological functions including anti-aging and antioxidant effects. The objectives of this study are to compare the antimelanogenic effects of fresh ginseng extract (FGE) and GINST extract and to elucidate the functional mechanism. The concentration of total ginsenosides in FGE and GINST was measured using ultraperformance liquid chromatography with a C18 column. B16F10 cells were treated with FGE and GINST for 72 h to assess melanin content, tyrosinase activity, and protein levels of microphthalmia-associated transcription factor (MITF) and tyrosinase-related protein-1 (TRP-1). The activity of kinases involved in mitogen-activated protein kinase (MAPK) signaling, such as extracellular signal-regulated kinases (ERK), c-Jun N-terminal kinases (JNK), and p38 mitogen-activated protein kinases (p38), were measured using western blots. While neither FGE nor GINST inhibited the activity of mushroom tyrosinase directly, GINST decreased melanogenesis and tyrosinase activity markedly. Furthermore, our results indicate that GINST downregulated the levels of MITF and TRP-1 possibly by suppressing JNK signaling. We concluded that, when compared to FGE, GINST has a superior antimelanogenic effect mediated by the downregulation of MITF, TRP-1, and intracellular tyrosinase activity via the JNK signaling pathway. Thus, we suggest that GINST has the potential to be used as a novel skin whitening agent.

Metabolism of 20(S)-Ginsenoside Rg₂ by Rat Liver Microsomes: Bioactivation to SIRT1-Activating Metabolites

20(S)-Ginsenoside Rg₂ (1) has recently become a hot research topic due to its potent bioactivities and abundance in natural sources such as the roots, rhizomes and stems-leaves of Panaxginseng. However, due to the lack of studies on systematic metabolic profiles, the prospects for new drug development of 1 are still difficult to predict, which has become a huge obstacle for its safe clinical use. To solve this problem, investigation of the metabolic profiles of 1 in rat liver microsomes was first carried out. To identify metabolites, a strategy of combined analyses based on prepared metabolites by column chromatography and ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF/MS) was performed. As a result, four metabolites M1–M4, including a rare new compound named ginsenotransmetin A (M1), were isolated and the structures were confirmed by spectroscopic analyses. A series of metabolites of 1, M_A–M_G, were also tentatively identified by UPLC-Q-TOF/MS in rat liver microsomal incubate of 1. Partial metabolic pathways were proposed. Among them, 1 and its metabolites M1, M3 and M4 were discovered for the first time to be activators of SIRT1. The SIRT1 activating effects of the metabolite M1 was comparable to those of 1, while the most interesting SIRT1 activatory effects of M3 and M4 were higher than that of 1 and comparable with that of resveratrol, a positive SIRT1 activator. These results indicate that microsome-dependent metabolism may represent a bioactivation pathway for 1. This study is the first to report the metabolic profiles of 1invitro, and the results provide an experimental foundation to better understand the in vivo metabolic fate of 1.

High-Performance Liquid Chromatography with Diode Array Detector and Electrospray Ionization Ion Trap Time-of-Flight Tandem Mass Spectrometry to Evaluate Ginseng Roots and Rhizomes from Different Regions

Ginseng, Panax ginseng C. A. Meyer, is an industrial crop in China and Korea. The functional components in ginseng roots and rhizomes are characteristic ginsenosides. This work developed a new high-performance liquid chromatography coupled with electrospray ionization ion trap time-of-flight multistage mass spectrometry (LC-ESI-IT-TOF-MS(n)) method to identify the triterpenoids. Sixty compounds (1-60) including 58 triterpenoids were identified from the ginseng cultivated in China. Substances 1, 2, 7, 15-20, 35, 39, 45-47, 49, 55-57, 59, and 60 were identified for the first time. To evaluate the quality of ginseng cultivated in Northeast China, this paper developed a practical liquid chromatography-diode array detection (LC-DAD) method to simultaneously quantify 14 interesting ginsenosides in ginseng collected from 66 different producing areas for the first time. The results showed the quality of ginseng roots and rhizomes from different sources was different due to growing environment, cultivation technology, and so on. The developed LC-ESI-IT-TOF-MS(n) method can be used to identify many more ginsenosides and the LC-DAD method can be used not only to assess the quality of ginseng, but also to optimize the cultivation conditions for the production of ginsenosides.