Three New Triterpenoid Saponins from Notoginseng Medicinal Fungal Substance

Three new triterpenoid saponins, named ginsenoside‐Rh₂₃ ( 1 ), ginsenoside‐Rh₂₄ ( 2 ), and ginsenoside‐Rh₂₅ ( 3 ), were isolated from notoginseng medicinal fungal substance. Their structures were elucidated by a combination of 1D‐ and 2D‐NMR, MS and chemical analysis. Compounds 1  –  3 exhibited moderate cytotoxic activity against MCF‐7 and NCI‐H460 cancer cell lines.     

Three New Steriodal Saponins from the Rhizomes of Tupistra chinensis Baker

The phytochemical constituent investigation on the 70 % ethanol extract of the rhizomes of Tupistra chinensis Baker resulted in the isolation of three new steroidal saponins which were named tuchinosides A–C ( 1 – 3 ). Their structures were determined by extensive spectrum analysis and chemical evidence, especially 2D NMR and HR-ESI-MS techniques. In addition, the cytotoxicity of compounds 1–3 against several human cancer cell lines was evaluated.     

Inhibition of NO Production by Grindelia argentina and Isolation of Three New Cytotoxic Saponins

A bioassay‐guided phytochemical analysis of the ethanolic extract of Grindelia argentina Deble & Oliveira ‐Deble (Asteraceae) allowed the isolation of a known flavone, hispidulin, and three new oleanane‐type saponins, 3‐O‐β‐D ‐xylopyranosyl‐(1→3)‐β‐D ‐glucopyranosyl‐2β,3β,16α,23‐tetrahydroxyolean‐12‐en‐28‐oic acid 28‐O‐β‐D ‐xylopyranosyl‐(1→2)‐β‐D ‐apiofuranosyl‐(1→3)‐β‐D ‐xylopyranosyl‐(1→3)‐α‐L ‐rhamnopyranosyl‐(1→2)‐α‐L ‐arabinopyranosyl ester ( 2 ), 3‐O‐β‐D ‐glucopyranosyl‐2β,3β,23‐trihydroxyolean‐12‐en‐28‐oic acid 28‐O‐β‐D ‐xylopyranosyl‐(1→2)‐β‐D ‐apiofuranosyl‐(1→3)‐β‐D ‐xylopyranosyl‐(1→3)‐α‐L ‐rhamnopyranosyl‐(1→2)‐α‐L ‐arabinopyranosyl ester, ( 3 ) and 3‐O‐β‐D ‐xylopyranosyl‐(1→3)‐β‐D ‐glucopyranosyl‐2β,3β,23‐trihydroxyolean‐12‐en‐28‐oic acid 28‐O‐β‐D ‐xylopyranosyl‐(1→2)‐β‐D ‐apiofuranosyl‐(1→3)‐β‐D ‐xylopyranosyl‐(1→3)‐α‐L ‐rhamnopyranosyl‐(1→2)‐α‐L ‐arabinopyranosyl ester ( 4 ), named grindeliosides A–C, respectively. Their structures were determined by extensive 1D‐ and 2D‐NMR experiments along with mass spectrometry and chemical evidence. The isolated compounds were evaluated for their inhibitory activities against LPS/IFN‐γ‐induced NO production in RAW 264.7 macrophages and for their cytotoxic activities against the human leukemic cell line CCRF‐CEM and MRC‐5 lung fibroblasts. Hispidulin markedly reduced LPS/IFN‐γ‐induced NO production (IC₅₀ 51.4 μM ), while grindeliosides A–C were found to be cytotoxic, with grindelioside C being the most active against both CCRF‐CEM (IC₅₀ 4.2±0.1 μM ) and MRC‐5 (IC₅₀ 4.5±0.1 μM ) cell lines.     

Alveld-Producing Saponins

Stabursvik (1959) described the saponin fraction of Narthecium ossifragum as a sarsasapogenin glycoside with the structure arabinosegalactose-xylose-glucose-sarsasapogenin. In a renewed study of the phototoxic lamb disease alveld, in which this saponin has been implicated (Ender 1955), we have looked more closely at the saponin fraction. We find that there are two saponins, one major and one minor. Both have a branched trisaccharide on C-3 of the sapogenin. Galactose is directly attached to C-3 in both saponins. The major saponin has glucose and arabinose attached to galactose, the minor saponin has glucose and xylose. We suggest the names narthecin and xylosin for the spirostanol form of these two saponins. In fresh juice from leaves we find little narthecin, however. Most of the saponin is present in the furostanol form, with glucose on C-26. Enzymatic hydrolysis showed this glucose to be bound as a β-glucoside. From specific rotations in partial hydrolysates we conclude that the saccharide on C-3 is a β-D-glucoside, α-L-araboside, β-D-galactoside.     

Camellidins,Antifungal Saponins Isolated from Camellia japonica

Two triterpenoid saponins were isolated from an aqueous or a methanolic extract of camellia (Camellia japonica) leaf. They had an antifungal activity characterized by abnormal germination of conidia. These saponins were composed of 3βhydroxy-18β-acetoxy-28-norolean-12-en-16-one or 3β, 8β-dihydroxy-28-norolean-12-en-16-one as aglycon, and d-glucuronic acid, dglucose and two moles of dgalactose as the sugar moiety. The authors have named these new saponins “Camellidin,” which might have value for studies in the fields of phytopathology and biochemistry.     

Saponins in cereals

Saponins are a diverse family of secondary metabolites that are produced by many plant species, particularly dicots. These molecules commonly have potent antifungal activity and their natural role in plants is likely to be in protection against attack by pathogenic microbes. They also have a variety of commercial applications including use as drugs and medicines. The enzymes, genes and biochemical pathways involved in the synthesis of these complex molecules are largely uncharacterized for any plant species. Cereals and grasses appear to be generally deficient in saponins with the exception of oats, which produce both steroidal and triterpenoid saponins. The isolation of genes for saponin biosynthesis from oats is now providing tools for the analysis of the evolution and regulation of saponin biosynthesis in monocots. These genes may also have potential for the development of improved disease resistance in cultivated cereals.     

Saponins of Chlorophytum Species

The genus Chlorophytum (Liliaceae) owing to the presence of pharmacologically important saponins has attracted interest of the scientific community to investigate the chemistry of the saponins and study their cytotoxicity. Chloromaloside-A having cytotoxicity against cancer cell lines has been isolated from C. malayense, while saponins from C. borivilianum are gaining popularity as substitute for viagra. The paper presents a review of different saponins isolated from the Chlorophytum species and their pharmacological importance.     

Saponins in Pollen

Phosphate buffered saline (PBS) extracts of pollen of 34 out of 95 angiosperm species (in 40 families) tested, lysed human and/or snake head fish (Channa striatus Bloch) erythrocytes during assay for lectins in pollen. The bitter taste of the pollen extracts of these 34 species, the formation of a stable foam on shaking and the ability to lyse erythrocytes, suggested the presence of saponins, which have not, so far, been reported from pollen. Thin Layer Chromatography (TLC) and Mass Spectrum (MS) of the erythrocyte-lysing extracts of pollen of the garden gladiolus (Gladiolus gandavensis Van Hout.) confirmed that the pollen contained both triterpenoidal and steroidal saponins. The implications for the presence of saponins in pollen inhaled from the atmosphere, in the diagnosis and management of pollen allergy are discussed.     

甾体皂甙的生物合成

近年来,人们分离鉴定了许多结构新颖的皂甙,阐明了它们的结构及生物活性,并对甾体皂甙的生物合成途径进行了较为深入的研究。异戊烯二磷酸在香叶二磷酸合成酶、法呢二磷酸合成酶、鲨烯合成酶和鲨烯环氧酶催化下合成2,3-环氧化鲨烯,再经环氧化鲨烯环化酶催化下形成三萜进而转化成甾醇,甾醇经羟化酶、糖基转移酶和β-糖苷酶的修饰,形成各种类型的甾体皂甙。本文重点介绍了甾体皂甙生物合成中所需要的关键酶,特别是以往研究较少的糖酶,主要为3-O-糖基转移酶,26-O-β-糖苷酶,并对甾体皂甙生物合成的前景进行了展望。     

Saponins, classification and occurrence in the plant kingdom

Saponins are a structurally diverse class of compounds occurring in many plant species, which are characterized by a skeleton derived of the 30-carbon precursor oxidosqualene to which glycosyl residues are attached. Traditionally, they are subdivided into triterpenoid and steroid glycosides, or into triterpenoid, spirostanol, and furostanol saponins. In this study, the structures of saponins are reviewed and classified based on their carbon skeletons, the formation of which follows the main pathways for the biosynthesis of triterpenes and steroids. In this way, 11 main classes of saponins were distinguished: dammaranes, tirucallanes, lupanes, hopanes, oleananes, taraxasteranes, ursanes, cycloartanes, lanostanes, cucurbitanes, and steroids. The dammaranes, lupanes, hopanes, oleananes, ursanes, and steroids are further divided into 16 subclasses, because their carbon skeletons are subjected to fragmentation, homologation, and degradation reactions. With this systematic classification, the relationship between the type of skeleton and the plant origin was investigated. Up to five main classes of skeletons could exist within one plant order, but the distribution of skeletons in the plant kingdom did not seem to be order- or subclass-specific. The oleanane skeleton was the most common skeleton and is present in most orders of the plant kingdom. For oleanane type saponins, the kind of substituents (e.g. -OH, =O, monosaccharide residues, etc.) and their position of attachment to the skeleton were reviewed. Carbohydrate chains of 18 monosaccharide residues can be attached to the oleanane skeleton, most commonly at the C3 and/or C17 atom. The kind and positions of the substituents did not seem to be plant order-specific.     

燕麦纽替皂苷的研究

采用乙醇回流提取,再经AB-8大孔树脂、MCI柱和ODS反相柱层析柱分离,理化方法及1H NMR,13CNMR等方法鉴定结构,从燕麦中得三个纽替皂苷类化合物:Avenacoside A(1)、Avenacoside B (2)、燕麦纽替皂苷C(3).其中化合物3为首次从禾本科植物中分离得到.     

Saponins from Lonicera bournei

The lupane-triterpene glycosides, bourneioside A and bourneioside B, and two known saponins were isolated from Lonicera bournei Hemsl. The structures of bourneioside A and B were elucidated as 3-O-beta-D-glucopyranosyl-23-hydroxy-lup-20(29)-en-28-oic acid-28-O-beta-D-glucopyranosyl ester and 3-O-beta-D-glucopyranosyl-23-hydroxy-lup-20(29)-en-28-oic acid-28-O-[beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranosyl] ester, respectively, on the basis of spectral data and chemical evidence.     

Saponins from Lysimachia candida

Three saponins were isolated from Lysimachia candida Lindl. By spectral and chemical analysis, they were identified as primulagenin A-3-O-β-D-xylopyranosy( 1→2)-β-D-glucopyranosyl( 1→4)-[β-D-glu- copyranosyl(1→2) ] -a-L-arabinopyranoside ( 1 ), protoprimulagenin A-3-O-β-D-xylopyranosyl( 1→2)-β-D-glu- copyranosyl( 1→4)-[ β-D-glucopyranosyl ( 1 →2) ]-a-L-arabinopyranoside ( lysikoianoside, 2) and a-spinas- teml-glucopyranoside (3) respectively. 1 is a new compound named candidoside.     

圆果雪胆中的皂甙成分

从圆果雪胆（Ｈｅｍｓｌｅｙａ ａｍａｂｉｌｉｓ）的块茎中分离到１０个化合物,其中３个雪胆皂甙是首次从该种植物中得到,它们的结构通过光谱和化学的方法鉴定为齐墩果酸－３－Ｏ－α－吡喃阿拉伯糖（１→３）－β－葡萄糖醛酸甙,２８－Ｏ－β－Ｄ－吡喃葡萄糖齐墩果酸３－Ｏ－α－吡喃阿拉伯糖（１→３）－β－Ｄ－葡萄糖醛酸,２８－Ｏ－β－Ｄ－吡喃葡萄糖齐墩果酸３－Ｏ－「β－Ｄ－吡喃葡萄糖（１→２）」－「α－吡喃阿     

油菜蜂花粉中皂苷化学成分的研究

油菜蜂花粉煮沸灭酶,减压蒸干,用80%乙醇提取,经AB-8大孔树脂、MCI柱和ODS反相柱层析柱分离,得到4个皂苷类化合物,通过理化方法、1H NMR、13C NMR等手段鉴定他们的化学结构,分别为:3,22-二羟基,3-O-β-D-葡萄糖-齐墩果烷(1)、3,22-二羟基,3-O-β-D-吡喃葡萄糖基(1→2)-β-D-吡喃葡萄糖基-[-β-D-吡喃葡萄糖(1→6)]-齐墩果烷(2)、3,22-二羟基,3-O-β-D-吡喃葡萄糖基(1→2)-β-D-吡喃葡萄糖基-[-β-D-吡喃葡萄糖(1→6)]-齐墩果酸(3)和3-O-β-D-葡萄糖-谷甾醇苷(4)。其中,皂苷1～3在油菜蜂花粉中首次报导。     

Saponins of two alfalfa cultivars

A saponin mixture was separated from the forage of DuPuits and Lahontan cultivars of Medicago sativa and found to contain about 30 saponins. Glucose, galactose, xylose, arabinose and rhamnose, were the principal sugars; the sapogenins comprised soyasapogenols A and B, lucernic acid, medicagenic acid together with four unidentified but related triterpenoids. Medicagenic acid was the predominant sapogenin of the DuPuits cultivar, whereas soyasapogenot A was prominent in Lahontan saponins. Galactose was found in the saponins of monocarboxylic or nonacidic sapogenins but was absent in those containing dicarboxylic sapogenins, such as medicagenic acid.     

Triterpene Saponins from Polygalaceae

The aim of this review is to give updated results on the chemistry and biological activities of Polygalaceae saponins from literature data and from authors’ studies. During the last decade the improvement of isolation and structure elucidation techniques allowed the characterization of about 150 complex triterpene saponins from Polygalaceae having mainly preatroxigenin, medicagenic acid and presenegenin as aglycone. The sequence 3-O-(β-d-glucopyranosyl)-presenegenin 28-[O-α-L-rhamnopyranosyl-(1→2)-β-d-fucopyranosyl] ester with additional acylations with p-methoxy-, di- or trimethoxycinnamoyl groups at the position 4 of the fucopyranosyl moiety often encountered in the genera Polygala, Muraltia, Carpolobia, and Securidaca may represent a chemotaxonomic marker for the Polygalaceae family. The biological and pharmacological properties of some Polygalaceae species such as in vitro activity on the central nervous system, the hypoglycemic, cytotoxic, immunomodulatory activities and in vivo immunoadjuvant properties are highlighted.     

Role of glycosidases in the membranlytic, antifungal action of Saponins.

In studies on the membranlytic action of various saponins on mycelium of Botrytis cinerea and Rhizoctonia solani digitonin, alpha-hederin and tomatin caused considerable leakage of free amino acids, while aescin and theasaponin were less effective. Cyclamin significantly damaged cell membranes of R. solani, but did not change the selective permeability of B. cinerea. Cell membrane disruption was accompanied by an enzymatic conversion of saponins into their corresponding aglycones in cell membrane vicinity, an effect which was significantly inhibited by aldonolactones, known inhibitors of beta-glycosidases. These results lead to the conclusion that the hardly water soluble aglycones are the active part of the saponin molecules, the saponins themselves being only water soluble transport forms. It follows, that the presence of appropriate glycosidases in cell membranes, capable of converting saponins into their aglycones, is a prerequisite for the membranlytic action of saponins. The similarity of the membranlytic effects of saponins towards fungi and erythrocytes is descussed.     

Saponins from Deutzia corymbosa.

Two new saponins were isolated from Deutzia corymbosa and characterized as: echinocystic acid-3-O-[alpha-L-arabinopyranosyl(1----4)]alpha-L- arabinopyranoside and echinocystic acid-3-O-[beta-D-galactopyranosyl(1----4)alpha-L- rhamnopyranosyl(1----4)]alpha-L-arabinopyranoside. Umbellferone and sitosterol-beta-D-glucoside were also isolated and characterized.     

Saponins from Steganotaenia araliacea.

Six saponins have been isolated and identified from the leaves of Steganotaenia araliacea. They were identified as 3-O-[beta-D-galactopyranosyl(1----2)-(beta-D-galactopyranosyl (1----3))-beta-D-glucuronopyranosyl]-21-O-tigloyl and -21-O-angeloyl-R1-barrigenol, 3-O-[beta-D-glucopyranosyl(1----2)-(beta-D-xylopyranosyl (1----3))-beta-D-glucuronopyranosyl]-21-O-tigloyl and -21-O-angeloyl-R1-barrigenol, 3-O-[beta-D-glucopyranosyl(1----2)-(beta-D-glucopyranosyl-(1----3))-(alp ha-L- rhamnopyranosyl(1----4))-beta-D-glucopyranosyl] steganogenin and 3-O-[(beta-D-galactopyranosyl(1----2)-beta-D-glucuronopyranosyl]-2 8-O- beta-D-glucopyranosyl olean-12-ene-28-oic acid. Steganogenin is a new 17,22-seco-oleanolic acid derivative. The structures of the saponins were established by analysis of their 1H and 13C NMR spectra with the help of 2D-experiments and by Californium Plasma Desorption Mass Spectrometry.