Steroidal saponin

The spiroketal function is derived from the cholesterol side-chain by a series of oxygenation reactions, hydroxylating C-16 and one of the 

About 600 species of Dioscorea (Dioscoreaceae) are known, and a number of these are cultivated for their large starchy tubers, commonly called yams, which are an important food crop in many parts of the world. Important edible species are Dioscorea alata and D. esculenta (S E Asia), D. rotundata and D. cayenensis (W Africa) and D. trifida (America). A number of species accumulate quite high levels of saponins in their tubers, which make them bitter and inedible, but these provide suitable sources of steroidal material for drug manufacture. 

Powdered Dioscorea (wild yam) root or extract is also marketed to treat the symptoms of menopause as an alternative to hormone replacement therapy (see page 279). Although there is a belief that this increases levels of progesterone, which is then used as a biosynthetic precursor of other hormones, there is no evidence that diosgenin is metabolized in the human body to progesterone, and any beneficial effects may arise from diosgenin itself. 

As the demand for natural fibres declined due to the availability of synthetics, so did the supply of sisal waste and thus hecogenin. In due course, hecogenin became a more valuable commodity than sisal, and efforts were directed specifically towards hecogenin production. This has resulted in the cultivation of Agave hybrids with much improved hecogenin content. 

The fermented sap of several species of Mexican Agave provides the alcoholic beverage pulque. Distillation of the fermented sap produces tequila. 

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Theory The assay of cholesterol is solely based on the fact that practically all 3 (3-hydroxysterols e.g., cholesterol, readily produces an insoluble molecular addition complex with pure digitonin (1 1)—a steroidal saponin isolated from either Digitalis purpurea or Digitalis lanata. The complex thus obtained is crystalline in nature, fairly stable and possesses very low solubilities. 

Ginseng has a mix of chemical constituents that are classified as steroidal saponins (table 5.7) (Robbers et al. 1996 Attele et al. 1999). These are glycosides that have been categorized into ginsenosides, panaxosides, and chikusetsusaponins. The major pharmacologically active constituents... 

The primary chemicals of interest in chilies are capsaicinoids, namely capsaicin (0.02%) and dihydrocapsaicin (figure 8.11). Also found are flavonoids, carotenoids (capsanthin), steroid saponins (capsicidin), and ascorbic acid or vitamin C (0.2%). Capsaicin has a vanilloid chemical structure. Mechanisms of Action... 

Saponins Mustard oils Steroidal saponins, triterpene saponins... 

African elephants avoid plants with high contents of total phenols, steroidal saponins, and lignin (Jachmann, 1989). 

Mimaki, Y. et al., Flavonol glycosides and steroidal saponins from the leaves of Cestrum noctur-num and their cytotoxicity, J. Nat. Prod., 64, 17, 2001. 

Fig. 1A-C. Examples of different classes of saponins A the triterpenoid saponin avenacin A-1 from roots of Avena spp B the steroidal saponin gracillin, from Costus speciosus C the steroidal glycoalkaloid a-tomatine from tomato (Lycopersicon spp.)...

Heflmann, E. (1967). Biochemistry of steroidal saponins and glycoalkaloids. Floydia, 30,209-230. 

The difficulty of separating L-arabinose from L-rhamnose has already been noted, and, in a model study directed towards the analysis of steroidal saponins, it was found that a column of (cyanoethyl)sili-cone (XF-1105) was particularly suitable for resolving L-arabinose, D-xylose, and L-rhamnose.31... 

The two major types of steroidal sapogenin are diosgenin and hecogenin. Steroidal saponins are used in the commercial production of sex hormones for clinical use. For example, progesterone is derived from diosgenin. 

Allium chinense Max. A. odorum L. A. sativum L. A. tuberosum Roxb. A. uliginosum G. Don Da Suan (Garlic) (bulb) Allicin, allistatin, glucominol, neo-allicin, steroidal saponins, polysaccharides, furostanol saponins, proto-isoerubosides, diallyl sulfide.33 49 438 490-510 Antibacterial, antimutagenic, anticarcinogenesis, carminative, antiarrhythmic, lower plasma cholesterol and low-density lipoproteins, prevent thrombosis, hypotensive and vessel protective effect. 

Anemarrhena asphodeloides Bunge. Zhi Mu (rhizome) Steroidal saponins, mangiferin, isomangiferin, sarsasapogenin, markogenin, neogitogenin.101133 Antipyretic, anti-inflammatory, sedative, antibacterial. 

N.A. Steroidal saponins.126 Strengthens a weak digestion, improves appetite, it has hormonal effect. It counters excessive sweating, frequent urination, and chronic thirst. 

N.A. Steroidal saponins, albuminoides, diosgenin, progestoron, sapogenin.126 Hormonal effect, treat vaginal discharge, diuretic and anti-inflammatory properties. 

N.A. Steroidal saponins, phytosterols (beta- sitosterol), starch, resin, sarsapic acid, minerals.99 Anti-inflammatory and cleansing. Relieve skin eczema, psoriasis, itchiness. 

N.A. Aletris farinosa L. Steroidal saponins, diosgenin, volatile oil, resin." For gynecological problems during menopause. Treat loss of appetite, indigestion, flatulence, and bloating. 

N.A. Caulophyllwn thalietroides (L.) Michx. Caulophylline, caulosaponin, methylcytisine, anagyrine, steroidal saponins, laburnine, magnoflorine.99 103 276 Antispasmodic, diuretic, antirheumatic, promote menstrual flow, induce abortion. 

N.A. Solanum dulcamara L. Steroidal alkaloids, solasodine, soldulcamaridine, steroidal saponins, tannins.99 Treat eczema, itchiness, psoriasis, and warts. It relieves asthma, chronic bronchitis, and rheumatic conditions. 

Steroid alkaloid glycosides Steroid glycosides Steroid saponins... 

Previously included, at least in part, in the Liliaceae or Amarylli-daceae, the Agavaceac, familiar plants in arid America, are known for (heir content of steroidal saponins which have been used for conversion to bioactive steroids of medicinal importance. It is... 

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