The structure of calibagenin

The main sapogenin of Calibanus hookerii, calibagenin, C₂₇H₄₆O₃, is a new steroidal sapogenin with an open side chain. The structure has been determined by chemical and spectrometric studies as cholest-5-en-3β,16ξ,22ξ-triol. The phytochemical relationships of open side chain sapogenins are discussed.     

Pridentigenin E,a triterpenoid sapogenin from Primula denticulata

The triterpenoid sapogenin pridentigenin E, isolated from Primula denticulata, has been identified as dihydrocyclamiretin D.     

A new sapogenin in the saponins of Zizyphus jujuba,Hovenia dulcis and Bacopa monniera

Acid hydrolysis of the saponin of the seeds of Zizyphus jujuba afforded ebelin lactone, which yielded the sapogenin, jujubogenin, on Smith-de Mayo degradation. The mechanism of conversion of jujubogenin into ebelin lactone has been elucidated. Hovenoside G of Hovenia dulcis and bacoside A of Bacopa monniera which produce ebelin lactone on acid hydrolysis have also been found to yield jujubogenin on Smith-de Mayo degradation.     

Hormonal control of steroid levels in tissue cultures from Trigonella foenumgraecum

The free and bound sterol and sapogenin levels of static and suspension cultures of Trigonella foenumgraecum have been investigated. Variations in the levels and distribution of these steroidal compounds with alterations in medium composition and culture age are reported. Synergism between auxin and cytokinin was observed in certain combinations and antagonism in others.     

The structure of mollugogenol-f,a new triterpenoid sapogenin from Mollugo hirta

The constitution of mollugogenol-F, a new triterpenoid sapogenin isolated from Mollugo hirta (family: Ficoidaceae), has been established as 3β,16β,22-trihydroxyisohopane.     

27-Hydroxyruscogenin,a new spirostan sapogenin from Semele androgyna

The new steroid sapogenin 27-hydroxyruscogenin has been isolated from stems and leaves of Semele androgyna L.; its structure was determined spectroscopically and by synthesis from 25(27)-dehydroruscogenin.     

Cardenagenin,a steroidal sapogenin from Calibanus hookerii

One new steroidal sapogenin with an open side chain was isolated from the rhizome of Calibanus hookerii. The structure has been determined by spectroscopic studies as 14α-hydroxy-calibagenin.     

25S-Dihydrodracogenin: A new spirostan sapogenin from Semele androgyna

From stems and leaves of Semele androgyna L. the new steroid sapogenin 25S-dihydrodracogenin (Ia) has been isolated and its structure confirmed by conversion into the acetates of 25R-dihydrosansevierigenin (Id) and ruscogenin (If) and by partial hydrogenation of dracogenin.     

1β-Hydroxyneotigogenin,a sapogenin from Solanum polyadenium leaves

A new sapogenin has been isolated from leaves of Solanum polyadenium P.I. 161728, a clone that is highly resistant to Colorado potato beetle and potato leaf hopper. The structure of this compound has been established as 1β-hydroxyneotigogenin, 5α-spirostan-1β,3β-diol.     

Solanolide,a steroid lactone sapogenin from Solanum hispidum

Solanolide, a new C₂₂ steroid lactone sapogenin isolated from the leaves of Solanum hispidum Pers., has been characterized as 3β, 6α, 16β-trihydroxy-5α-pregnane-20S-carboxylic acid (22, 16)-lactone from ¹H and ¹³C NMR analyses and correlation with neochlorogenin.     

Steroidal sapogenins from leaves of Agaveae species

The steroidal sapogenins yielded by the leaves of 34 species and 1 cultivar of Agave, 1 species of Beschorneria, 1 species of Doryanthes and 3 species of Furcraea have been studied. Steroidal sapogenins were found in extracts of most of the species examined. Smilagenin, sarsasapogenin, diosgenin, yamogenin, tigogenin, neotigogenin, gloriogenin, gentrogenin, hecogenin, sisalagenin, 9-dehydrohecogenin and gitogenin were detected. Gloriogenin was found only in A. ghiesbrechtii, yamogenin in A. horrida and A. rigidissima, neo-tigogenin in A. horrida and A. toneliana and gitogenin in A. filifera, F. cabua, F. gigantea and F. selloa cv marginata. The highest yield of smilagenin was obtained from both A. haynaldii and A. rigidissima, of sarsasapogenin from A. attenuata, of diosgenin from A. ellemeetiana, of tigogenin from A. haynaldii and of hecogenin from F. cabua.     

Andesgenin,a new steroid sapogenin from Solanum hypomalacophyllum

The structure of andesgenin, a new steroid sapogenin isolated from Solanum hypomalacophyllum, was determined on the basis of spectral data and synt     

9(11)-dehydroagapanthagenin,a new spirostan sapogenin from Agapanthus africanus

The structure of 9(11)-dehydroagapanthagenin, a new spirostan sapogenin isolated from the rhizomes of Agapanthus africanus, was determined on the basis of spectral and chemical evidence.     

Dormantinol,a possible precursor in solanidine biosynthesis,from budding Veratrum grandiflorum

A new sapogenin, dormantinol, was isolated from budding Veratrum, and identified as (25S)-cholest-5-ene-3β,22α,26-triol by spectral analysis and its synthesis from dormantinone. Cholesterol was also identified in the budding Veratrum.     

Esculentosides: Insights into the potential health benefits,mechanisms of action and molecular targets

BackgroundEsculentosides and related phytolaccosides form a group of oleanene-type saponins isolated from plants of the Phytolaccaceae family, essentially Phytolacca esculenta, P. americana and P. acinosa. This chemical family offers a diversity of glycosylated compounds, including molecules with a mono-, di- or tri-saccharide unit at position C-3, and with or without a glucose residue at position C-28. The esculentosides, which derive essentially from the sapogenin jaligonic acid or its 30-methyl ester phytolaccagenin, exhibit anti-inflammatory, antifungal and anticancer activities.PurposeThe objective of the review was to identify the 26 esculentosides (ES) and phytolaccosides known to date, including 16 monodesmosidic and 10 bidesmosidic saponins, and to review their pharmacological properties and molecular targets.MethodologyThe retrieval of potentially relevant studies was done by systematically searching of scientific databases like Google Scholar and PubMed in January-May 2020. The main keywords used as search terms were related to esculentosides, phytolaccosides and Phytolaccaceae. The systematic search retrieved about 110 papers that were potentially relevant and after an abstract-based selection, 68 studies were analyzed in details and discussed.ResultsThe structural relationship between the compounds and their sapogenin precursors has been studied. In addition, the pharmacological properties of the main ES, such as ES-A, -B and -H, have been analyzed to highlight their mode of action and potential targets. ES-A is a potent inhibitor of the release of cytokines and this anti-inflammatory activity contributes to the anticancer effects observed in vitro and in vivo. Potential molecular targets of ES-A/B include the enzymes cyclooxygenase 2 (COX-2) and casein kinase 2 (CK2). In addition, the targeting of the protein high-mobility group box 1 (HGMB1) by ES-A/B is proposed, based on molecular modeling and the structural analogy with the related saponin glycyrrhizin, a potent HGMB1 alarmin inhibitor.ConclusionMore work is needed to properly characterize the molecular targets but otherwise compounds like ES-A and ES-H emerge as potent anti-inflammatory and anticancer agents and ES-B as an antifungal agent. A preclinical development of these three compounds should be considered.     

Influence of hormonal supplementation on steroid levels during callus induction from seeds of Trigonella foenumgraecum

Time course studies were carried out on steroid levels during induction of callus from seedlings of Trigonella foenumgraecum. There were marked variations in the levels with time and according to the hormonal supplementation of the medium and, whilst sapogenin level always fell below that in the seed, sterol levels tended to be higher.     

Dammarenediol-II synthase, the first dedicated enzyme for ginsenoside biosynthesis, in Panax ginseng

Panax ginseng produces triterpene saponins called ginsenosides, which are classified into two groups by the skeleton of aglycones, namely dammarane type and oleanane type. Dammarane-type ginsenosides dominate over oleanane type not only in amount but also in structural varieties. However, their sapogenin structure is restricted to two aglycones, protopanaxadiol and protopanaxatriol. So far, the genes encoding oxidosqualene cyclase (OSC) responsible for formation of dammarane skeleton have not been cloned, although OSC yielding oleanane skeleton (β-amyrin synthase) has been successfully cloned from this plant. In this study, cDNA cloning of OSC producing dammmarane triterpene was attempted from hairy root cultures of P. ginseng by homology based PCR method. A new OSC gene (named as PNA) obtained was expressed in a lanosterol synthase deficient (erg7) Saccharomyces cerevisiae strain GIL77. LC-MS and NMR analyses identified the accumulated product in the yeast transformant to be dammarenediol-II, demonstrating PNA to encode dammarenediol-II synthase.     

Spirostanic diosgenin precursors from Dioscorea composita tubers

The main saponin from the fresh tuber of Dioscorea composita was dioscin and from the fermented material 3-O-[α-l-rhamnopyranosyl(1→4)-β-d-glucopyranosyl]diosgenin. The ¹³C NMR chemical shifts of saponins were used in the determination of their structure. No free sapogenin was isolated from the fresh tuber.     

Sapogenins from Guaiacum officinale

Acid hydrolysis of the saponins from the stem bark of Guaiacum officinale yielded the new sapogenin 3β,20η-dihydroxy-30-norolean-12-en-28-oic acid and the artifacts 3β-hydroxy-30-norolean-12,19-dien-28-oic acid and its methyl ester. Larreagenin, sitosterol and oleanolic acid were also isolated.     

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.