Oleanane-type Triterpene Saponins Research Articles

Oleanane-type saponins from Lysimachia laxa Baudo and their anti-bacterial activities.

Seven new oleanane-type triterpene saponins, lysimaponins A-G, were isolated from aerial parts of Lysimachia laxa Baudo. Their chemical structures have been elucidated by analysis of spectroscopic and chemical methods. All compounds were evaluated for their anti-bacterial effects against Microcystis aeruginosa, Vibrio parahaemolyticus, V. harveyi, V. vulinificus, V. cholerae, and V. alginolyticus. All compounds showed potent anti-bacterial activities against the cyanobacteria M. aeruginosa with IC50 values ranging from 14.4 ± 1.2 to 35.3 ± 2.2 µg/mL. Compounds 1, 2, 4-7 inhibited V. parahaemolyticus with MIC values ranging from 64 to 256 µg/mL. The results suggested that saponins from L. laxa could be potential anti-cyanobacteria agents.

Symplosaponins A–D: New acylated oleanane-type triterpene saponins from Symplocos cochinchinensis and their hepatoprotective effect

Four new acylated oleanane-type triterpene saponins, symplosaponins A–D (1–4) were successfully isolated from the leaves of Symplocos cochinchinensis (Lour.) S. Moore, alongside with five known compounds (5–9), 2-methoxy-4-prop-1-enylphenyl-1-O-β-D-apiofuranosyl-(1 → 6)-β-D-glucopyranoside (5), and 1-[O-β-d-xylopyranosyl-(1 → 6)-O-β-d-glucopyranosyl]-2,6-dimethoxy-4-propenyl-phenol (6), 6-O-p-coumaroylsucrose (7), arillatose B (8), and (−)-secoisolariciresinol-O-β-D-glucopyranoside (9). The structures of these compounds were elucidated through spectroscopic methods, comparison with existing data, and chemical methods. Furthermore, all compounds were assessed for their impact on hepatocellular viability using the Resazurin reduction assay. These investigations aimed to explore the potential hepatoprotective properties of isolated compounds. As a result, 1-[O-β-d-xylopyranosyl-(1 → 6)-O-β-d-glucopyranosyl]-2,6-dimethoxy-4-propenyl-phenol (6) and (−)-secoisolariciresinol-O-β-D-glucopyranoside (9) demonstrated statistically significant hepatoprotective activity in a concentration-dependent manner.

Oleanane-Type Triterpene Glycosides from Camellia phanii and Their α-Glucosidase Inhibitory Activity.

Three new oleanane-type triterpene saponins, named camphanosides A-C (1-3), along with five known compounds, chikusetsusaponin IVa (4), spinasaponin A 28-O-glucoside (5), (-)-epicatechin (6), (-)-epicatechin 3-O-gallate (7), and (-)-epigallocatechin 3-O-gallate (8) were isolated from the leaves Camellia phanii Hakoda & Ninh. Their structures were established by 1D and 2D-NMR and mass spectral analysis and chemical methods. Moreover, compounds 1-5 were also evaluated for α-glucosidase inhibitory activity. Compounds 1-3 exhibited moderate α-glucosidase inhibitory activity with IC50 values of 230.7±18.0, 251.4±22.7, and 421.4±25.6 μM, respectively.

New biofunctional effects of oleanane-type triterpene saponins.

In the current review, we describe the novel biofunctional effects of oleanane-type triterpene saponins, including elatosides, momordins, senegasaponins, camelliasaponins, and escins, obtained from Aralia elata (bark, root cortex, young shoot), Kochia scoparia (fruit), Polygala senega var. latifolia (roots), Camellia japonica (seeds), and Aesculus hippocastanum (seeds), considering the following biofunctional activities: (1) inhibitory effects on elevated levels of blood alcohol and glucose in alcohol and glucose-loaded rats, respectively, (2) inhibitory effects on gastric emptying in rats and mice, (3) accelerative effects on gastrointestinal transit in mice, and (4) protective effects against gastric mucosal lesions in rats. In addition, we describe (5) suppressive effects of the extract and chakasaponins from Camellia sinensis (flower buds) on obesity based on inhibition of food intake in mice. The active saponins were classified into the following three types: (1) olean-12-en-28-oic acid 3-O-monodesmoside, (2) olean-12-ene 3,28-O-acylated bisdesmoside, and (3) acylated polyhydroxyolean-12-ene 3-O-monodesmoside. Furthermore, common modes of action, such as involvements of capsaicin-sensitive nerves, endogenous NO and PGs, and possibly sympathetic nerves, as well as common structural requirements, were observed. Based on our findings, a common mechanism of action might mediate the pharmacological effects of active saponins. It should be noted that the gastrointestinal tract is an important action site of saponins, and the role of the saponins in the gastrointestinal tract should be carefully considered.

A novel strategy for the discovery and validation of allergic component and its action mechanism in Red Ginseng

Red ginseng (a processed product of ginseng) is a famous herbal medicine or healthcare product widely used in Asia. However, there are many reports about anaphylactoid reaction of red ginseng. This study aims to establish a novel strategy for discovering and validating allergic component and its action mechanism in red ginseng. Firstly, RBL-2H3 cell degranulation experiment was performed by real-time cell analysis (RTCA) system and β-hexosaminase release test to illustrate the anaphylactoid reaction induced by red ginseng. Then, combined with ultra-performance liquid chromatography quadrupole/time of flight mass spectrometry (UPLC-Q/TOF-MS) analysis, the main components of red ginseng for inducing degranulation of RBL-2H3 cells was explored. Furthermore, the compounds with the parent nucleus structure of allergic component were studied to figure out whether they could induce RBL-2H3 cell degranulation, and the relationship between the structures of compounds and degranulation was further investigated. Finally, the underlying mechanism of allergic components was explored based on network toxicology and molecular docking method, which was further verified by western blotting analysis. Our findings demonstrated that red ginseng extract could induce degranulation of RBL-2H3 cells, and ginsenoside Ro (an oleanane-type triterpene saponin), was confirmed to be the main allergic component. Meanwhile, both ginsenoside Ro (Ro) and other oleanane-type triterpene saponins could induce degranulation of RBL-2H3 cells, and the compound with disaccharide chain on C3 position had the strongest activity of degranulation. And their mechanism of inducing degranulation of RBL-2H3 cells involved in PI3K-Akt pathway. The results would provide a reference for the quality control and evaluation of safety of herb medicines or healthcare products containing oleanane-type triterpenoid saponins. Our method offers a novel strategy for screening allergic components in red ginseng and promoting further study of safety evaluation of red ginseng.

Integration of lipidomics and metabolomics for the authentication of camellia oil by ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry coupled with chemometrics

The integration of lipidomics and metabolomics approaches, based on UPLC-QTOF-MS technology coupled with chemometrics, was established to authenticate camellia oil adulterated with rapeseed oil, peanut oil, and soybean oil. Lipidomics revealed that the glyceride profile provides a prospective authentication of camellia oil, but no characteristic markers were available. Sixteen characteristic markers were identified by metabolomics. For camellia oil, all six markers were sapogenins of oleanane-type triterpene saponins. Lariciresinol, sinapic acid, doxercalciferol, and an unknown compound were identified as markers for rapeseed oil. Characteristic markers in peanut oil were formononetin, sativanone, and medicarpin. In the case of soybean oil, the characteristic markers were dimethoxyflavone, daidzein, and genistein. The established OPLS-DA and OPLS prediction models were highly accurate in the qualitative and quantitative analyses of camellia oil adulterated with 5% other oils. These results indicate that the integration of lipidomics and metabolomics approaches has great potential for the authentication of edible oils.

Anti-Atherosclerotic Effect of Afrocyclamin A against Vascular Smooth Muscle Cells Is Mediated via p38 MAPK Signaling Pathway.

Objective Research suggests that fine particulate matter (PM2.5) contributes to the expansion and development of atherosclerosis. Infiltration and proliferation of vascular smooth muscle cells (VSMCs) from the blood vessel media into the intima, is an important step in the atherosclerosis pathophysiology. Afrocyclamin A, is an oleanane-type triterpene saponin, isolated from Androsace umbellate, which is commonly used in Chinese herbal medicine. In the study, we examined the effect of Afrocyclamin A on PM2.5-induced VSMCs proliferation and scrutinized possible mechanisms of action. Materials and Methods In the experimental study, counting Kit-8 (CCK-8) assay was used for estimation of VSMCs viability. BrdU immunofluorescence was used for estimation of VSMCs proliferation. The levels of antioxidant parameters such as malonaldehyde (MDA), superoxide dismutase (SOD), and glutathione (GSH); proinflammatory cytokines such as interleukin-1β (IL-1β), IL-6, tumor necrosis factor-α (TNF-α), nitric oxide (NO), endothelin-1 (ET-1), and vascular cell adhesion molecule-1 (VCAM-1), were estimated. The expression of proliferating cell nuclear antigen (PCNA) and phospho-p38 MAPK (p-p38 MAPK) was assessed. Results Compared to PM2.5-treated cells, in addition to reducing PM2.5-induced VSMCs proliferation, Afrocyclamin A reduced the expression of PCNA and p-p38 MAPK, down-regulated the level of TNF-α, IL-1β, IL-6, VCAM-1, MDA and ET-1, and up-regulated SOD, GSH and NO level. Furthermore, the anti-proliferative effect of Afrocyclamin A was considerably increased following co-incubation of Afrocyclamin A with SB203580 (p38 MAPK inhibitor) in comparison with Afrocyclamin A-treated cells. ConclusionBased on the results, we can conclude that Afrocyclamin A might reduce PM2.5-induced VSMCs proliferation via reduction of p38 MAPK signaling pathway.

Polythosides A and B, two new triterpenoid saponins from the roots of Acacia polyacantha Willd. (Mimosaceae)

• Two new triterpenoid saponins were isolated from Acacia polyacantha . • Their structures were elucidated by analysis of 1D and 2D-NMR studies. • They were not significantly cytotoxic to H4IIE cells even at 100 μM. Two new oleanane-type triterpene saponins, named polythosides A and B ( 1 and 2 ), together with a known compound, silphioside E ( 3 ), were isolated from the roots of Acacia polyacantha . Their structures were elucidated by analysis of 1D and 2D-NMR experiments, and mass spectrometry (HR-ESITOF-MS) as oleanolic acid 3- O - β - d -galactopyranosyl-(1→2)- β - d -xylopyranosyl-(1→6)-[ β - d -xylopyranosyl-(1→4)]-[ β - d -xylopyranosyl-(1→2)]- β - d -galactopyranoside ( 1 ), 3- O -[ β - d -galactopyranosyl-(1→2)- β - d -xylopyranosyl-(1→6)-[ β - d -xylopyranosyl-(1→4)]-[ β - d -xylopyranosyl-(1→2)]- β - d -galactopyranosyl] oleanolic acid-28- O - β - d -glucopyranosyl ester ( 2 ) and 3- O - β - d -glucopyranosyl-(1→2)- β - d -glucopyranosyl] oleanolic acid 28- O - β - d -glucopyranosyl ester ( 3 ). The cytotoxic effect of isolated saponins was evaluated on the H4IIE rat hepatoma cell line. The results show that none of the compounds (assayed at 100 μM) showed cytotoxicity against H4IIE cells.

Arenarosides A-G, Polyhydroxylated Oleanane-Type Saponins from Polycarpaea arenaria and their Cytotoxic and Antiangiogenic Activities.

Seven new polyhydroxylated oleanane-type triterpene saponins, arenarosides A-G (1-7), together with four known compounds, were isolated from an ethanol extract of the aerial parts of the Vietnamese plant Polycarpaea arenaria. The chemical structures of the newly isolated oleanane saponins were elucidated on the basis of spectroscopic and spectrometric analysis, especially 2D NMR and HRMS. Biological evaluation revealed that 3, 4, 6, and 7 showed moderate activities against four human cancer cell lines (A549, HTC116, PC3, and RT112) with IC50 values of 6.0-9.9 μM, and 3, 4, 5, and 7 also displayed promising antiangiogenesis effects with IC50 values <5 μM in the test system used. Among the isolates, arenaroside D (4) exhibited the most potent inhibitory effects, not only in cancer cell proliferation but also in angiogenic activities. Preliminary SAR studies revealed that the presence of an acetyl group at C-22 in oleanane-type triterpene saponins increases these bioactivities.

Comprehensive phytochemical analysis and sedative-hypnotic activity of two Acanthopanax species leaves.

Acanthopanax senticosus leaves (SCL) and Acanthopanax sessiliflorus leaves (SFL), which are usually made into functional teas, possess similar pharmacological activities. With the aim of revealing their chemical compositions and evaluating their sedative-hypnotic effects, comprehensive metabolite profiling analysis based on ultra-high-performance liquid chromatography coupled to quadrupole time-of-flight tandem mass spectrometry (UPLC-Q/TOF-MS) and high-performance liquid chromatography with evaporative light scattering detection (HPLC-ELSD) as well as bioassay studies in mice were performed for the first time. Firstly, a total of 75 compounds (including 69 shared components) were identified or briefly characterized. Results indicated that the leaves of the two species were both rich in phytochemicals and contained similar structural types. Secondly, 20 and 7 chemical markers were identified from SCL and SFL, respectively. Five oleanane-type triterpene saponins (ciwujianoside C1, C3, D2, E and saniculoside N) and two lupine-type triterpene saponins (1-deoxychiisanoside and 24-hydroxychiisanoside) may be used for rapid identification of SCL and SFL. Thirdly, the contents of rutin, hederacoside D, ciwujianoside B, -C3, -E and ursolic acid in SCL (0.308%, 0.024%, 0.042%, 0.131%, 0.038%, and 0.255%, respectively) were higher than in SFL (0.067%, 0.005%, 0.012%, 0.015%, 0.002%, and 0.087%, respectively). Fourthly, an in vivo bioassay verified that both SCL and SFL could inhibit autonomous activity, shorten sleep latency and prolong sleep duration in a dose-dependent manner. To a certain degree, SCL showed a higher and more stable effect. The hypnotic effect could be inhibited by flumazenil (FLU). The two leaves not only had an obvious antagonism action of p-chlorophenoxyacetic acid (pCPA) but also showed a synergistic hypnotic effect with 5-hydroxytryptophan (5-HTP). The beneficial bioactivity may be mediated by 5-hydroxytryptamine (5-HT) and γ-aminobutyric acid (GABA). Finally, network pharmacology analysis showed that the undifferentiated and differentiated compounds were the material basis for the similar and the different activities of two leaves. Some typical chemical markers (such as saniculoside N, hederacoside D, ciwujianoside C3, -E and ursolic acid, 24-hydroxychiisanoside and 1-deoxyisochiisanoside) were the potential active compounds and could be used as quality markers in the future. The present study furnished a basis for the further development and utilization of the leaves of these two Acanthopanax species.

Enhancement of an In Vivo Anti-Inflammatory Activity of Oleanolic Acid through Glycosylation Occurring Naturally in Stauntonia hexaphylla.

Stauntonia hexaphylla (Lardizabalaceae) has been used as a traditional herbal medicine in Korea and China for its anti-inflammatory and analgesic properties. As part of a bioprospecting program aimed at the discovery of new bioactive compounds from Korean medicinal plants, a phytochemical study of S. hexaphylla leaves was carried out leading to isolation of two oleanane-type triterpene saponins, 3-O-[β-d-glucopyranosyl (1→2)-α-l-arabinopyranosyl] oleanolic acid-28-O-[β-d-glucopyranosyl (1→6)-β-d-glucopyranosyl] ester (1) and 3-O-α-l-arabinopyranosyl oleanolic acid-28-O-[β-d-glucopyranosyl (1→6)-β-d-glucopyranosyl] ester (2). Their structures were established unambiguously by spectroscopic methods such as one- and two-dimensional nuclear magnetic resonance and infrared spectroscopies, high-resolution electrospray ionization mass spectrometry and chemical reactions. Their anti-inflammatory activities were examined for the first time with an animal model for the macrophage-mediated inflammatory response as well as a cell-based assay using an established macrophage cell line (RAW 264.7) in vitro. Together, it was concluded that the saponin constituents, when they were orally administered, exerted much more potent activities in vivo than their sapogenin core even though both the saponins and the sapogenin molecule inhibited the RAW 264.7 cell activation comparably well in vitro. These results imply that saponins from S. hexaphylla leaves have a definite advantage in the development of oral medications for the control of inflammatory responses.

Oleanane-type triterpene saponins from Aralia armata leaves and their cytotoxic activity

Two new, aramatosides A and B (1 and 2), together with seven known oleanane-type triterpene saponins (3–9) were isolated from the leaves of Aralia armata. Their structures were determined by combination of HR-ESI-MS, 1 D and 2 D NMR spectral data as well as comparison with the previous literature. Compounds 6–9 exhibited cytotoxic effects towards three human cancer cell lines (HT29, A2058, and A549) with IC50 values ranging from 2.01 ± 0.17 to 18.8 ± 1.17 µM. Especially, compound 7 (narcissiflorin) showed significant cytotoxic activity against HT29 and A549 cell lines with IC50 values of 2.02 ± 1.65 and 2.01 ± 0.17 µM, respectively, which are smaller than those of positive control irinotecan hydrochloride (IC50 values of 10.3 ± 1.32 and 9.89 ± 0.19 µM).

Anti-breast cancer and toxicity studies of total secondary saponin from Anemone raddeana Rhizome on MCF-7 cells via ROS generation and PI3K/AKT/mTOR inactivation

Ethnopharmacological relevanceThe rhizome of Anemone raddeana Regel (A. raddeana) is a famous traditional Chinese medicine (TCM) recorded in Chinese Pharmacopoeia for the treatment of carbuncle and swelling. Carbuncle swollen is an explanation of tumor in the theory of TCM and softening and resolving hard mass effects are one of the important pharmacological activities of A. raddeana.Aim of the study: We investigated the potential anti-breast cancer effect and toxicological properties of alkali-ethanol extract from A. raddeana, namely total secondary saponin (TSS). Materials and methodsAnti-proliferative effect of total saponin of A. raddeana (ATS) and TSS were tested using MTT assay. Hoechst staining, flow cytometry analysis, DCFH-DA fluorescence microscopy and western blot were carried out to evaluate the mechanisms of action of TSS. The potential anti-breast cancer activity and toxicological properties of TSS were tested in vivo. ResultsATS and TSS could inhibit the proliferation of A549, HepG2, MCF-7, MDA-MB-231 and SKBr-3 cells, especially for MCF-7 cells. Flow cytometry analysis revealed that TSS (10, 12 and 15 μg/ml) could induce cell cycle arrest on G0/G1 phase and promote apoptosis of MCF-7 cells. TSS could increase Bax/Bcl-2 ratio, elevate cytochrome c levels in cytosol and activate caspase-3/9. In addition, TSS also induced ROS generation and inactivated PI3K/AKT/mTOR pathway which may involved in the mitochondrial dysfunction of MCF-7 cells. TSS showed slight toxic at the dosage of 100 and 200 mg/kg by oral administration without any toxic potential for 28 days. TSS (50, 100 and 200 mg/kg) showed significant inhibitory effect on growth of transplanted tumor in mice. At last, twenty-three C-3 monosaccharide oleanane-type triterpene saponins were tentatively identified, which may contributed to the anti-cancer activity of TSS. ConclusionThis study demonstrated that TSS exhibited anti-proliferative and pro-apoptosis activities on MCF-7 cells via ROS-mediated activation of mitochondrial apoptosis pathway. TSS might be used as chemotherapeutic agent for the treatment of breast cancer with relatively low toxicity.

Chemical components from Metapanax delavayi leaves and their anti-BHP activities in vitro

Two previously undescribed oleanane-type triterpene saponins named liangwanosides III–IV, and one undescribed eudesmane glycoside named liangwanoside A were obtained from the leaves of Metapanax delavayi, a Chinese folk medicine especially for tea used in Yunnan, together with four known compounds. The structures of the undescribed compounds were determined by detailed spectroscopic (1D/2D NMR), HR-ESI-MS data analysis and chemical evidence. The activity against human benign prostate hyperplasia was evaluated with BPH-1 cell line. Most of the isolated compounds showed moderate inhibitory activity against BPH-1 cells at 100 and 50 μM in vitro.

Afrocyclamin A, a triterpene saponin, induces apoptosis and autophagic cell death via the PI3K/Akt/mTOR pathway in human prostate cancer cells

BackgroundAfrocyclamin A, an oleanane-type triterpene saponin, was isolated from Androsace umbellata which used as a traditional herbal medicine. PurposeThis study aimed to explore the anticancer activity of afrocyclamin A on human prostate cancer cells in vitro as well as in vivo. MethodsCytotoxicity, cell cycle distribution, apoptosis, and autophagic cell death were measured following exposure to afrocyclamin A. In vivo antitumor activity of afrocyclamin A was assessed in a xenograft model. The protein levels of p-Akt, p-mTOR, Bax, Bcl-2, caspase-3, and caspase-9 were quantified using western blot analysis. ResultsIn DU145 cells, afrocyclamin A increased cytotoxicity, caused changes in cell morphology, and induced sub-G0/G1 phase indicating increased apoptosis. Afrocyclamin A robustly induced autophagic cell death as demonstrated by the conversion of LC3B-I to LC3B-II, and the formation of autophagic vacuoles as revealed by western blot analysis and fluorescence staining, respectively. Afrocyclamin A also inhibited the phosphorylation of PI3K, Akt, and mTOR, suggesting their role in afrocyclamin A induced cell death. In addition, afrocyclamin A inhibited cell migration and invasion in concentration and time-dependent manners. In an in vivo xenograft model, afrocyclamin A inhibited the growth of DU145 cells. ConclusionAfrocyclamin A has anticancer activity via the PI3K/Akt/mTOR pathway, which leads to cell death.

A naturally occuring triterpene saponin ardisiacrispin B displayed cytotoxic effects in multi-factorial drug resistant cancer cells via ferroptotic and apoptotic cell death

IntroductionMultidrug resistance of cancer cells constitutes a serious problem in chemotherapy and a challenging issue in the discovery of new cytotoxic drugs. Many saponins are known to display anti-cancer effects. In this study, the cytotoxicity and the modes of action of a naturally occuring oleanane-type tritepene saponin, ardisiacrispin B isolated from the fruit of Ardisia kivuensis Taton (Myrsinaceae) was evaluated on a panel of 9 cancer cell lines including various sensitive and drug-resistant phenotypes. MethodsResazurin reduction assay was used to evaluate cytotoxicity and ferroptotic cell death of samples; caspase-Glo assay was used to detect the activation of caspases in CCRF–CEM leukemia cells. Flow cytometry was used for cell cycle analysis and detection of apoptotic cells by annexin V/PI staining, analysis of mitochondrial membrane potential (MMP) and measurement of reactive oxygen species (ROS). ResultsArdisiacrispin B displayed significant cytotoxic effects in the 9 tested cancer cell lines with IC50 values below 10 µM. The IC50 values ranges were 1.20 µM (towards leukemia CCRF–CEM cells) to 6.76 µM [against heptocarcinoma HepG2 cells] for ardisiacrispin B and 0.02 µM (against CCRF–CEM cells) to 122.96 µM (against resistant CEM/ADR5000 leukemia cells) for doxorubicin. Collateral sensitivity of resistant HCT116p53−/− colon adenocarcinoma cells to ardisiacripsin B was observed. Ardisiacrispin B induced apoptosis in CCRF–CEM cells via activation of inititator caspases 8 and 9 and effector caspase 3/7, alteration of MMP and increase in ROS production. Ferroptosis also contributed to the cytotoxicity of ardisiacrispin B. ConclusionsThe studied oleanane-type triterpene saponin is a good cytotoxic molecule that deserve more detailed exploration in the future, to develop novel cytotoxic drugs to combat both sensitive and drug-resistant cancers.

Enhanced biosynthesis of saponins by coronatine in cell suspension culture of Kalopanax septemlobus.

Kalopanax septemlobus is a medicinal woody species of the family Araliaceae, and the pharmaceutical properties of saponins obtained from K. septemlobus suggest that K. septemlobus has the potential to be a crude drug and dietary health supplement. In this study, we established cell suspension culture of K. septemlobus to develop a sustainable source of natura-ceuticals. Friable calli were used for establishing cell suspension culture. The maximum amount of total saponins (1.56mg/60ml suspension) was obtained during the 15th day of incubation, whereas the maximum capacity of saponin production was reached after day 6 (0.42μg/mg of fresh weight). The total saponin production in the cell suspension of K. septemlobus was significantly increased by coronatine (COR) at 160% at a dose of 1μM compared with the mock-treated control, whereas methyl jasmonate treated cells exhibited less increase in total saponin level as compared to the COR-treated cells. In addition, the elicitation of COR strongly induced the expression of beta-amyrin synthase, thus resulting in the accumulation of oleanolic acid (2.369±0.98μg/mg of extract), a precursor for oleanane-type triterpene saponins. These results indicate that COR is an efficient elicitor for inducing phytochemicals in cell suspension culture and that it provides the possibility for producing saponins of K. septemlobus using cell suspension culture.

Congmujingnosides B-G, triterpene saponins from the stem of Aralia chinensis and their protective effects against H2O2-induced myocardial cell injury

Phytochemical investigation of the stem of Aralia chinensis yielded six new oleanane-type triterpene saponins named as congmujingnosides B-G (1–6). The new ones were elucidated on the basis of the chemical and spectroscopic analysis. Protective effects of compounds 1−6 were tested against H2O2-induced H9c2 cardiomyocyte injury, and the data showed that compounds 1 and 5 had significant cell-protective effects. No significant DPPH radical scavenging activity was observed for compounds 1−6.

Highly efficient synthesis of bioactive oleanane-type saponins

Leveraging on Schmidt glycosylation method, a highly efficient approach to obtain oleanane-type triterpene saponins was fixed, whereby oleanyl mono-, disaccharide (guaianin N), trisaccharide (elatoside E), as well as tetrasaccharide (elatoside F) were obtained efficiently. The synthetic investigation has resulted in the discovery of the effect of branch-sugar incorporation sequence on the overall synthetic efficiency. Moreover, through bioactivity investigation, the cytotoxic activity of the obtained triterpenoid saponins was evaluated, and the preliminary structure-activity relationship was deduced.

The Chemical Constituents of Uninvestigated Plants in Hiroshima Prefecture.

Recently, the investigation of bioactive constituents from natural products has been performed extensively around the world, yet many plants remain to be studied, even now. The author is especially interested in saponins, which are included in various natural products and Kampo medicines. Based on these study aims, we isolated the chemical constituents of Dianthus japonicus and Clethra barbinervis. The aerial parts of Dianthus japonicus were isolated into nine new (1-9) and seven known oleanane-type triterpene saponins. The structural elucidation of their chemical constituents was examined by several spectroscopic methods. Two new C-glycosyl flavones, two glycosidic derivative of anthranilic acid amides and a maltol glucoside were also isolated from this plant. The isolated compounds were evaluated according to cytotoxic inhibition toward A549 cell lines. Compounds 7-9 showed moderate inhibitory activity. The isolation of a MeOH extract of Clethra barbinervis leaves led to three new triterpene glucosides, i.e. an ursane (ryobunin A, 22), a seco-ursane (ryobunin B, 23) and an oleanane-type glucoside (ryobunin C, 24), along with four known compounds.