Type Saponins Research Articles

Conversion of Protopanaxadiol Type Saponins to Ginsenoside Rg3 by Lemon

The ability of fresh lemon (Citrus limon) to convert protopanaxadiol-type saponins into ginsenoside Rg3 was investigated, and the structures of 20(S)-ginsenoside Rg3 (1) and 20(R)-ginsenoside Rg3 (2) were identified by 1H NMR and 13C NMR spectroscopy. The experiment showed that lemon possesses the strong ability to hydrolyze ginsenosides. When protopanaxadiol-type saponins (16 mg/mL) were hydrolyzed by fresh lemon juice at 80 degrees C for 3 hrs, the conversion ratios of ginsenoside Rb1, Rb2, Rc and Rd were 92.9%, 90.0%, 96.90/0 and 55.5%, respectively, and the yields of 20(S)-ginsenoside Rg3 and 20(R)-ginsenoside Rg3 were, respectively, 31.2% and 28.3%.

Korean Red Ginseng Saponin Fraction Downregulates Proinflammatory Mediators in LPS Stimulated RAW264.7 Cells and Protects Mice against Endotoxic Shock

Korean red ginseng has shown therapeutic effects for a number of disease conditions. However, little is known about the antiinflammatory effect of Korean red ginseng saponin fraction (RGSF) in vitro and in vivo. Therefore, in this study, we showed that RGSF containing 20(S)-protopanaxadiol type saponins inhibited nitric oxide production and attenuated the release of tumor necrotic factor (TNF)-α, interleukin (IL)-6, granulocyte monocyte colony stimulating factor (GMCSF), and macrophage chemo-attractant protein-1 in lipopolysaccharide (LPS) stimulated murine macrophage RAW264.7 cells. Moreover, RGSF down-regulated the mRNA expressions of inducible nitric oxide synthase, cyclooxyginase-2, IL-1β, TNF-α, GMCSF, and IL-6. Furthermore, RGSF reduced the level of TNF-α in the serum and protected mice against LPS mediated endotoxic shock. In conclusion, these results indicated that ginsenosides from RGSF and their metabolites could be potential sources of therapeutic agents against inflammation.

Paviosides A–H, eight new oleane type saponins from Aesculus pavia with cytotoxic activity

A phytochemical analysis of Aesculus pavia has led to the isolation of eight novel triterpenoid saponins, based on oleane type skeleton and named paviosides A–H (1a, 1b–4a, 4b). On the basis of chemical, and 2D NMR and mass spectrometry data, the structures of the new compounds were elucidated as 3-O-[β-d-xylopyranosyl (1→2)] [-β-d-glucopyranosyl (1→4)]-β-d-glucopyranosiduronic acid 21-tigloyl-22-acetyl barringtogenol C (1a), 3-O-[β-d-xylopyranosyl (1→2)] [-β-d-glucopyranosyl (1→4)]-β-d-glucopyranosiduronic acid 21-angeloyl-22-acetyl barringtogenol C (1b), 3-O-[β-d-xylopyranosyl (1→2)] [-β-d-galactopyranosyl (1→4)]-β-d-glucopyranosiduronic acid 21-tigloyl-22-acetyl barringtogenol C (2a), 3-O-[β-d-xylopyranosyl (1→2)] [-β-d-galactopyranosyl (1→4)]-β-d-glucopyranosiduronic acid 21-angeloyl-22-acetyl barringtogenol C (2b), 3-O-[β-d-xylopyranosyl (1→2)] [-β-d-xylopyranosyl (1→4)]-β-d-glucopyranosiduronic acid 21-tigloyl-22-acetyl barringtogenol C (3a), 3-O-[β-d-xylopyranosyl (1→2)] [-β-d-xylopyranosyl (1→4)]-β-d-glucopyranosiduronic acid 21-angeloyl-22-acetyl barringtogenol C (3b), 3-O-[β-d-xylopyranosyl (1→2)] [-β-d-xylopyranosyl (1→4)]-β-d-glucopyranosiduronic acid 21-tigloyl-22-acetyl protoaescigenin (4a), and 3-O-[β-d-xylopyranosyl (1→2)] [-β-d-xylopyranosyl (1→4)]-β-d-glucopyranosiduronic acid 21-angeloyl-22-acetyl protoaescigenin (4b). The compounds showed cytotoxic activity on J-774, murine monocyte/macrophage, and WEHI-164, murine fibrosarcoma, cell lines. Among them, paviosides E–H (3a, 3b and 4a, 4b) showed higher activity with values ranging from 2.1 to 3.6μg/mL. Structure–activity relationship studies indicated the positive effect on the activity of xylose unit in the place of glucose, while a little detrimental effect is observed when glucose is substituted by galactose. The aglycone structure and the presence of a tigloyl or an angeloyl group at C-21 do not affect significantly the inhibitory activity on both tested cell lines.

Straightforward preparation of organic colloidal particles by harnessing spontaneous non-covalent interactions of active molecules from natural origin

We demonstrate a straightforward method to prepare organic colloidal particles based on the spontaneous molecular interactions between small molecular weight actives of natural origin. Representative reactive natural actives from three of the most researched classes of phytochemicals including berberine (isoquinoline alkaloid), tannic acid (polyphenol) and glycyrrhizin (olenane type saponin) were chosen for the study. Binding parameters (association constant, binding enthalpy and entropy) obtained from isothermal titration calorimetry indicated that berberine strongly interacted with tannic acid to form insoluble colloidal complex which could be stabilised in the presence of glycyrrhizin (due to its interaction with both berberine and tannic acid and also due to its amphiphilic nature). Working on this principle, the mutual interactions of these three natural actives were exploited to obtain stable spherical particles with a mean diameter of less than 100nm (77nm) simply by mixing the aqueous solutions of berberine:tannic acid:glycyrrhizin at molar ratio of 2:1:1. The involvement of aromatic chromophore (π–π*) system and charged N atom of berberine in the spontaneous interaction between berberine and tannic acid was confirmed from spectral analysis. X-ray diffraction study suggested formation of amorphous organic colloidal particles, and the spherical shape of colloidal particles was confirmed by transmission electron microscopy.

Evaluation of the immunomodulatory properties in mice and in vitro anti-inflammatory activity of cycloartane type saponins from Astragalus species

Ethnopharmacological relevanceAstragalus roots are used to treat leukemia and for their wound healing properties in Southeast Anatolia-Turkey. Materials and methodsIn vivo studies to investigate the effects of two Astragalus saponins were carried out on the immune response cytokines by using six to eight weeks old male Swiss albino mice. The production of IL-1β, TGF-1β, TNF-α, IL-2, IL-4 and IFN-γ cytokines was determined by ELISA. The spleen and lymph nodes, isolated from the mice subjects, were analyzed to realize induction of the surface antigen productions for IL-2Rα (CD25) and CD69. In addition, their effects on the targets of inflammation such as NF κB, iNOS and NAG-1 were investigated in cell-based assays. ResultsThe results suggested that AST VII and Mac B had positive effect on Th1 cytokine release (IL-2 and IFN-γ), and suppression on Th2 cytokine production (IL-4). The immunohistochemical results exhibited induction of both IL-Rα (CD25) and CD69 surface receptors justifying the Th1 cytokine release. The compounds did not affect NF-κB or NAG-1 activity but iNOS activity was inhibited by Mac B with an IC50 of 156μg/ml. ConclusionsThe results show that Ast VII and Mac B create powerful immunoregulatory effects without the stimulation of inflammatory cytokines in mice, and have no significant effect on the inflammatory cellular targets in vitro.

Phytochemical and Biological Studies on Aster novi-belgii

Aster is a large genus of the family Asteraceae (Compositae) comprising more than 200 species distributed around the world (1). Some of Aster species have been used in traditional medicine for the treatment of fever, cold, tonsillitis, snake bite and bee sting (2). Members of this genus are rich in triterpenoid saponins, two oleanan type saponins and three flavonoid compounds were isolated from Aster novi (3,4). Phytochemical investigation of the methanolic extract of Aster novi-belgii L. (Asteraceae) aerial part has led to the isolation and identification by spectroscopic means of four triterpenoid saponins, oleanolic acid 3-O-β-D-galactopyranosyl (1→3)-α-L-arabinopyranoside; 3-O-β-D- glucopyranosyl- 3β, 16 α- dihydroxyolean- 12- en- 28-oic acid-28-O-α-L- arabinopyranoside; {3-O-β-D- glucouronopyranosyl- 3β,16 α- dihydroxyolean- 12-en -23-oic acid 28-O-β-D- xylopyranosyl- (1→3)-β-D- xylopyranosyl- (1→4)- α-L-rhamnopyranosyl-(l→2)-α-L-arabinopyranoside} ester and {3-O-β-D-glucouronopyranosyl-3β,16 α- dihydroxyolean- 12-en- 23-oic acid 28-O-β-D- xylopyranosyl- (1→3)- β-D-xylopyranosyl (1→4)- [α-L- arabinopyranosyl- (1→3)] -α-L- rhamnopyranosyl- (l→2)- α-L-arabinopyranoside} ester, and four flavonoids; kaempferol, quercetin, kaempferol 3-O-β-D-glucopyranoside and quercetin 3-O-β-D-glucopyranoside. Moreover, the extract showed a molluscicidal activity against Biomphalaria alexandrina snails.

Genetic, Chemical and Pharmacological Diversity of Ginseng Drugs

Ginseng drugs derived from the underground parts of Panax species show a high potential to cure various kinds of diseases. In spite of traditional uses for several centuries, clinical evidences and systematical comparison have rarely been reported. One of the reasons is that herbal drugs from natural resources have difficulties in quality control of botanical sources and chemical constituents. Our studies through DNA sequence analysis and quantitative determination of 11 main saponins showed that 13 Panax taxa had the species-specific sequences in the plastid trnK gene and nuclear 18S rRNA gene, and each taxon possessed the characteristic pattern in chemical composition. The trnK/18S rDNA sequences could be used not only for accurate authentication of Ginseng drugs but also for a speculation of the chemical constituent pattern that affects pharmacological effects. An application of this result, DNA microarray for authentication of Ginseng drugs was developed and its efficacy was demonstrated. Furthermore, we focused on the Ginseng drugs to find out candidates capable of regenerating neuronal network in the dementia brain. The protopanaxadiol (ppd) type saponins were found to have neurite outgrowth activity in SK-N-SH cells. Since ppd-type saponins are known to be completely metabolized into 20-O-β-D-glucopyranosyl-(20S)-protopanaxadiol (M1) by intestinal bacteria when taken orally, further studies on M1 suggested that M1 had axonal extension activity in degenerated neurons, and ameliorate memory disorder and synaptic loss in Alzheimar's mouse model induced by Aß(25–35). M1 was shown to be effective in vitro and in vivo, indicating that Ginseng drugs containing ppd-type saponins may reactivate neuronal function in AD by p.o. administration.

Oleanene Glycosides of the Aerial Parts and Seeds of Bupleurum falcatum and the Aerial Parts of Bupleurum rotundifolium, and Their Evaluation as Anti-hepatitis Agents

To facilitate effective resource utilization, we have investigated triterpene saponins such as saikosaponin from the aerial parts of Bupleurum (B.) falcatum L., which are commonly discarded. Seven oleanene saponins were isolated from this plant; they were classified as the 13,28-epoxy type, 12-ene type, 9(11),12-diene type, and 28-acid type on the basis of their structural characteristics. For comparison, we also examined the oleanene saponins of the seeds of B. falcatum and the aerial parts of B. rotundifolium L. to obtain seven saponins and one sapogenol from the former and thirteen oleanene saponins from the latter. Several compounds obtained from them were investigated for their hepatoprotective activity and hepatotoxicity. The 13,28-epoxy type saponins had hepatoprotectivity. Ursane type showed hepatotoxicity from middle concentration. The 11,13(18)-diene type saponins did not express hepatoprotective activity. The 28-acid type saponin which has a glucosyl carboxy group showed hepatoprotective action.

New Lupane-type Triterpenoid Saponins from Leaves of Oplopanax horridus (Devil's Club)

Two new lupane type saponins, along with one known saponin were isolated from leaves of Oplopanax horridus (Devil's Club). The structures of the two new compounds were elucidated as 3alpha-hydroxy-lup-20(29)-ene-23, 28-dioic acid-3-O-beta-D-glucopyranoside (2) and 24-nor-3-oxo-lup-20(29)-en-28-oic acid-28-O-alpha-L-rhamnopyranosyl(1''' --> 4")-beta-D-glucopyranosyl(1" --> 6')-beta-D-glucopyranoside (3) on the basis of spectroscopic analysis and chemical evidence. The known compound was identified as 3alpha-hydroxy-lup-20(29)-ene-23, 28-dioic acid (1) by comparison of its spectral data with those reported. Compound 1 was isolated for the first time from the title plant.

Metabolic classification of South American Ilex species by NMR-based metabolomics

The genus Ilex to which mate ( Ilex paraguariensis) belongs, consists of more than 500 species. A wide range of metabolites including saponins and phenylpropanoids has been reported from Ilex species. However, despite the previous works on the Ilex metabolites, the metabolic similarities between species which can be used for chemotaxonomy of the species are not clear yet. In this study, nuclear magnetic resonance (NMR) spectroscopy-based metabolomics was applied to the classification of 11 South American Ilex species, namely, Ilex argentina, Ilex brasiliensis, Ilex brevicuspis, Ilex dumosa var. dumosa, I. dumosa var. guaranina, Ilex integerrima, Ilex microdonta, I. paraguariensis var. paraguariensis, Ilex pseudobuxus, Ilex taubertiana, and Ilex theezans. 1H NMR combined with principal component analysis (PCA), partial least square-discriminant analysis (PLS-DA) and hierarchical cluster analysis (HCA) showed a clear separation between species and resulted in four groups based on metabolomic similarities. The signal congestion of 1H NMR spectra was overcome by the implementation of two-dimensional (2D)- J-resolved and heteronuclear single quantum coherence (HSQC). From the results obtained by 1D- and 2D-NMR-based metabolomics it was concluded that species included in group A ( I. paraguariensis) were metabolically characterized by a higher amount of xanthines, and phenolics including phenylpropanoids and flavonoids; group B ( I. dumosa var. dumosa and I. dumosa var. guaranina) with oleanane type saponins; group C ( I. brasiliensis, I. integerrima, I. pseudobuxus and I. theezans) with arbutin and dicaffeoylquinic acids, and group D ( I. argentina, I. brevicuspis, I. microdonta and I. taubertiana) with the highest level of ursane-type saponins. Clear metabolomic discrimination of Ilex species and varieties in this study makes the chemotaxonomic classification of Ilex species possible.

Cytotoxic steroidal saponins from the flowers of Allium leucanthum.

Allium leucanthum C. Koch is an endemic Caucasian species that grows in Georgia. The flowers are used in traditional medicine. Phytochemical investigation allowed the isolation of seven spirostanol type saponins from the flowers. Their structures were elucidated on the base of NMR and HRESIMS spectrometry data. A new compound, which we have named leucospiroside A (5), has been identified as (25R)-5α-spirostane-2α,3β,6β-triol 3-O-β-glucopyranosyl-(1→3)-β-glucopyranosyl-(1→2)-[β-glucopyranosyl-(1→3)]-β-glucopyranosyl-(1→4)-β-galactopyranoside. The six others were known substances, but are described in this plant for the first time. The crude extract, spirostanol and furostanol fractions, as well as isolated compounds, were evaluated for their in vitro cytotoxic activity. Compounds 1-3 and 5 were found to be the most active, with relatively similar IC50 values ranging from 3.7 to 5.8 µM for a lung cancer cell line (A549) and 5.6 to 8.2 µM for a colon cancer cell line (DLD-1).

Comparison of the antiobesity effects of the protopanaxadiol‐ and protopanaxatriol‐type saponins of red ginseng

A previous study demonstrated that ginseng crude saponins prevent obesity induced by a high-fat diet in rats. Ginseng crude saponins are known to contain a variety of bioactive saponins. The present study investigated and compared the antiobesity activity of protopanaxadiol (PD) and protopanaxatriol (PT) type saponins, major active compounds isolated from crude saponins. Male 4-week-old Sprague-Dawley rats were fed with normal diet (N) or high-fat diet (HF). After 5 weeks, the HF diet group was subdivided into the control HF diet, HF diet-PD and HF diet-PT group (50 mg/kg/day, 3 weeks, i.p.). Treatment with PD and PT in the HF diet group reduced the body weight, total food intake, fat contents, serum total cholesterol and leptin to levels equal to or below the N diet group. The hypothalamic expression of orexigenic neuropeptide Y was significantly decreased with PD or PT treatment, whereas that of anorexigenic cholecystokinin was increased, compared with the control HF diet group. In addition, PD type saponins had more potent antiobesity properties than PT saponins, indicating that PD-type saponins are the major components contributing to the antiobesity activities of ginseng crude saponins. The results suggest that the antiobesity activity of PD and PT type saponins may result from inhibiting energy gain, normalizing hypothalamic neuropeptides and serum biochemicals related to the control of obesity.

PH 및 고온 열처리가 홍삼물추출물의 주종 사포닌 성분변화에 미치는 영향

This study was carried out to investigate the changes of ginsenosides composition in Korean red ginseng water extract (RGWE) after heated with high temperatures above <TEX>$100^{\circ}C$</TEX>. RGWEs were adjusted with pH 3.0, pH 7.0 and pH 10.0, respectively, and then heated at 100,110 and <TEX>$120^{\circ}C$</TEX> for 30 minutes by using autoclave. Total ginsenosides of RGWE treated with heating showed decreasing tendency when compared with control. By TLC analysis, decreasing effect of ginsenosides in RGWE were significantly observed in the acidic condition of pH 3.0, particulary. By HPLC analysis, total ginsenoside of control showed 1.89%, while those of RGWE treated with 100, 110 and <TEX>$120^{\circ}C$</TEX> showed 1.22, 1.05 and 0.97%, respectively. The ratio of protopanaxadiol (PD) to protopanaxatriol (Pr) saponins in control was 1.89, while that of PD/PT in treated RGWEs were level of 1.33 to 1.47. By the result of decreased ratio of PD/PT in RGWE, it was considered that PD type saponin such as ginsenoside<TEX>$-Rb_{1}$</TEX>, <TEX>$-Rb_{1}$</TEX>, -Rc and -Rd was more unstable than PT type saponin such as ginsenoside-Re and Rg against high temperature heating above <TEX>$100^{\circ}C$</TEX>.

Quantification and separation of protopanaxatriol and protopanaxadiol type saponins from Panax notoginseng with macroporous resins

20( S)-protopanaxatriol saponins (PTS) and 20( S)-protopanaxadiol saponins (PDS) are known as two groups of major ingredients in the root of Panax notoginseng and possess various pharmacological effects. In the present study, a simple method for preparative separation of PTS and PDS from P. notoginseng with macroporous resins was established. The adsorption characteristics of PTS and PDS on four types of macroporous resins, including D-101, DA-201, DM-301 and DS-401, have been compared. Among them, DS-401 resin showed the best separation behaviors. The equilibrium absorption data of PTS and PDS on DS-401 resin at 25 oC was fitted to the Freundlich isotherm. Dynamic adsorption and desorption tests have been performed in glass column packed with DS-401 resin for optimizing the process parameters. Due to different adsorption force to resin, the PTS and PDS were successfully separated with 30% and 80% (v/v) aqueous ethanol solutions, respectively. Based on the conditions optimized above, large-scale preparation of PTS and PDS from P. notoginseng was also carried out. The contents of PTS and PDS were increased from 22.5% and 16.4% in the PLE extract of the root of P. notoginseng to 88.2% and 92.6% in the final products with the recoveries of 80.2% and 82.3%, respectively.

Protopanaxadiol modulates LPS-induced inflammatory activity in murine macrophage RAW264.7 cells

Protopanaxadiol (PPD) is a mixture of protopanaxadiol type saponins with a dammarane skeleton, from Korean red ginseng (Panax ginseng C.A. Meyer; Araliaceae). Korean ginseng is well-known herb to treat almost all kinds of diseases in Oriental medicine. This herb was particularly prescribed for treatment various inflammatory diseases, including rheumatoid arthritis, atherosclerosis, and diabetes mellitus, for centuries. To understand the efficacy of ginseng against inflammatory diseases, we aimed to show anti-inflammatory activities of the PPD in murine macrophage cell line, RAW264.7 cells using nitric oxide (NO) production assay and the expressions of pro-inflammatory cytokines, such as tumor necrosis <TEX>$factor-{\alpha}$</TEX> (<TEX>$TNF-{\alpha}$</TEX>), interleukin-<TEX>$1{\beta}$</TEX> (IL-<TEX>$1{\beta}$</TEX>), and IL-6, and monocyte chemotactic protein-1 (MCP-1). We found that PPD saponin significantly blocked LPS (<TEX>$1{\mu}g/ml$</TEX>)-induced NO production in a dose-dependent manner. In addition, PPD abrogated the expressions of LPS-induced pro-inflammatory cytokines, such as IL-<TEX>$1{\beta}$</TEX> and MCP-1. Moreover, cyclooxygenase (COX)-2, a critical enzyme to produce prostaglandin E2 (PGE2), was significantly inhibited by PPD in LPS-activated RAW264.7 cells. Taken together, these results suggested that anti-inflammatory efficacy of Korean red ginseng on inflammatory diseases is, at least, due to the NO inhibitory activity and the inhibition of the expressional level of inflammatory cytokines and/or mediators.

New Furostanol Glycosides from the Rhizomes of Tacca integrifolia

The rhizomes of Tacca integrifolia Ker. Gawler (Taccaceae), a perennial plant growing in central region of Myanmar, are used in traditional medicine for the treatment of carbuncles, skin abrasion, skin diseases and various kinds of cancer. Previous studies on other Tacca species revealed the presence of highly oxygenated steroids named taccalonolides [1, 2] as well as sterol saponins [3]. Phytochemical investigation of the methanol extract of the rhizomes of T. integrifolia let to the isolation of two new furostanol type saponins, namely (25R)-26-[(β-D-glucopyranosyl)oxy]-22α-methoxyfurost-5-en-3β-yl O-α-L-rhamnopyranosyl-(1→2)-O-α-L-rhamnopyranosyl-(1→3)-β-D-glucopyranoside (1) and (25R)-26-[(β-D-glucopyranosyl)oxy]-22α-hydroxyfurost-5-en-3β-yl O-α-L-rhamnopyranosyl-(1→2)-O-α-L-rhamnopyranosyl-(1→3)-β-D-glucopyranoside (2), along with the known spirostanol type saponin, diosgenin-3β-O-α-L-rhamnopyranosyl (1→2)-O-α-L-rhamnopyranosyl-(1→3)-O-β-D-glucopyranoside.

Chemical characteristics for different parts of Panax notoginseng using pressurized liquid extraction and HPLC-ELSD

The chemical characteristics for different parts of Panax notoginseng, including root, fibre root, rhizome, stem, leaf, flower and seed, were determined using high performance liquid chromatography-evaporative light scattering detection (HPLC-ELSD) and pressurized liquid extraction (PLE). Eight major saponins, namely notoginsenoside R1, ginsenosides Rg1, Re, Rb1, Rc, Rb2, Rb3 and Rd were also quantitatively compared among the different parts of P. notoginseng. The chromatograms showed that there was significant difference between underground (root, fibre root, rhizome) and aerial (leaf and flower) parts from P. notoginseng, though the similarities of entire chromatographic patterns among tested samples from underground (0.965 ± 0.029, n = 12) and aerial parts (0.987 ± 0.014, n = 5) were similar, respectively. Especially, no saponin was detected in the seed of P. notoginseng. Hierarchical clustering analysis based on eight investigated saponins or the ratios of contents for ginsenoside Rg1/Rb1 and ginsenoside Rb3/Rb1 showed that the samples from different parts of P. notoginseng were divided into three main clusters. One cluster was underground parts, which contained rich protopanaxatriol and protopanaxadiol types saponins. The leaf and flower were in the same cluster, which contained protopanaxadiol type saponins only. Especially, ginsenoside Rc, Rb2 and Rb3, rare in the underground parts, were rich in aerial parts of P. notoginseng. The stem of P. notoginseng was another cluster. Based on the cluster analysis, the chemical characteristics for different parts of P. notoginseng were revealed. They are composite cluster (underground parts), protopanaxadiol cluster (aerial parts) and interim (stem) cluster, which was the one between the two typical clusters, respectively. The result shows that chemical characteristics of underground parts and aerial parts from P. notoginseng are obviously different, which is helpful for pharmacological evaluation and quality control of P. notoginseng.

Abeta(25-35)-induced memory impairment, axonal atrophy, and synaptic loss are ameliorated by M1, A metabolite of protopanaxadiol-type saponins.

We previously screened neurite outgrowth activities of several Ginseng drugs in human neuroblastoma, and demonstrated that protopanaxadiol (ppd)-type saponins were active constituents. Since ppd-type saponins are known to be completely metabolized to 20-O-beta-D-glucopyranosyl-20(S)-protopanaxadiol (M1) by intestinal bacteria when taken orally, M1 and ginsenoside Rb1, as a representative of ppd-type saponins, were examined for cognitive disorder. In a mouse model of Alzheimer's disease (AD) by Abeta(25-35) i.c.v. injection, impaired spatial memory was recovered by p.o. administration of ginsenoside Rb1 or M1. Although the expression levels of phosphorylated NF-H and synaptophysin were reduced in the cerebral cortex and the hippocampus of Abeta(25-35)-injected mice, their levels in ginsenoside Rb1- and M1-treated mice were almost completely recovered up to control levels. Potencies of the effects were not different between ginsenoside Rb1 and M1 when given orally, suggesting that most of the ginsenoside Rb1 may be metabolized to M1, and M1 is an active principal of ppd-type saponins for the memory improvement. In cultured rat cortical neurons, M1 showed extension activity of axons, but not dendrites. The axon-specific outgrowth was seen even when neuritic atrophy had already progressed in response to administration of Abeta(25-35) as well as in the normal condition. These results suggest that M1 has axonal extension activity in degenerated neurons, and improve memory disorder and synaptic loss induced by Abeta(25-35). M1 was shown to be effective in vitro and in vivo, indicating that Ginseng drugs containing ppd-type saponins may reactivate neuronal function in AD by p.o. administration.

Saponins from Swartzia langsdorffii: biological activities.

The presence of saponins and the molluscicidal activity of the roots, leaves, seeds and fruits of Swartzia langsdorffii Raddi (Leguminosae) against Biomphalaria glabrata adults and eggs were investigated. The roots, seeds and fruits were macerated in 95% ethanol. These extracts exerted a significant molluscicidal activity against B. glabrata, up to a dilution of 100 mg/l. Four mixtures (A2, B2, C and D) of triterpenoid oleanane type saponins were chromatographically isolated from the seed and fruit extracts. Two known saponins (1 and 2) were identified as beta-D-glucopyranosyl-[alpha-L-rhamnopyranosyl-(1->3)- beta-D-glucuronopyranosyl-(1->3)]-3beta-hydroxyolean-12-ene-28 -oate, and beta-D-glucopyranosyl-(1->3)-beta-D-glucuronopyranosyl-(1 ->3)]-3beta-hydroxyolean-12-ene-28-oate, respectively. These two saponins were present in all the mixtures, together with other triterpenoid oleane type saponins, which were shown to be less polar, by reversed-phase HPLC. The saponin identifications were based on spectral evidence, including H- H two-dimensional correlation spectroscopy, nuclear Overhauser and exchange spectroscopy, heteronuclear multiple quantum coherence, and heteronuclear multiple-bond connectivity experiments. The toxicity of S. langsdorffii saponins to non-target organisms was prescreened by the brine shrimp lethality test.

Four new oleanane type Saponins from Morina nepalensis var. alba

Four new oleanane type saponins, monepalosides G–J (1–4), were isolated from the water-soluble part of the whole plant of Morina nepalensis var. alba Hand-Mazz. On the basis of chemical and spectroscopic evidence, their structures were determined as 3-O-α-L-arabinopyranosyl-(1→3)-α-L-arabinopyranosyl oleanolic acid 28-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside (monepaloside G, 1), 3-O-α-L-arabinopyranosyl-(1→3)-β-D-xylopyranosyl oleanolic acid 28-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside (monepaloside H, 2), 3-O-α-L-arabinopyranosyl-(1→3)-[β-D-glucopyranosyl-(1→2)]-α-L-arabinopyranosyl oleanolic acid 28-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside (monepaloside I, 3), 3-O-β-D-glucopyranosyl-(1→4)-β-D-glucopyranosy-(1→3)]-α-L-arabinopyranosyl oleanolic acid 28-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside (monepaloside J, 4), respectively. Two-dimensional NMR spectra, including H–H COSY, HMQC, 2D HMQC–TOCSY, HMBC and ROESY were utilized in the structure elucidation and complete assignments of 1H and 13C NMR spectra.