Dioscorea

The major problem in such conversions is the degradation of the branched carbon side-chain on C-17 which is present in all abundant steroids and lacking in all steroid hormones. The most important starting material used in industry today is diosgenin from the Mexican dioscorea plant. It is degraded by the method of Marker to 16-dehydropregnenolone in 45% total yield. This compound is a key substance in the production of several hormones with anabolic, catabolic, and sexual effects. 

In Dioscorea hispida, Trigollenine is incorporated into the isoquinuclidine moiety of the alkaloid Dioscorine (208), as proved by a feeding experiment with [TOer/ y/- " C,2- H, H]trigollenine (88P3793). These results are consistent with the hypothesis for the biosynthesis of Dioscorine (208), Dumetorine and Dihydrodioscorine, which is presented in Scheme 68. 

Dioscorea, and the humble soybean. The advantage of using plants rather than valuable domestic animals as raw material is fairly obvious. 

Protein-Nitrogen Conservation in Fresh Stored Dioscorea Yams... 

Yam tubers of Dioscorea alata (Umudike cultivar), D. rotundata (asukwu and obiaturugo cultivars)" and D. cayenensis (water yam and Nkokpu cultivars) were obtained from the National Root Crops Research Institute, Umudike, Nigeria. Some tubers were stored 6 or 12 months at room temperature (25-27 °C), some in vacuum dessicators over a suitable dessicant, and some in paper bags placed in a dark cabinet (absence of circulating air). Fresh tubers were peeled by carefully scraping away the cork layer to minimize loss of outer tissue since much of the protein is concentrated here ( ). They were then cut into 2 cu. cm. pieces, quickly frozen with solid CO2 in 50 9 portions in plastic bags, and stored in a freezer until needed. 

Diosgenin (Fig. 4) is a steroid sapogenin produced by Dioscorea species. This natural product is used as a precursor for the commercial synthesis of medicinal steroids such as prednisolone, dexamethasone, norethisterone, and metenolone, among others. Microtuber-derived cell suspensions of Dioscorea doryophora were able to accumulate diosgenin at concentrations as high as 3.5% g dw. Embryogenic callus of Tribulus terrestris were also able to accumulate diosgenin (170.7 1.0 pg/g dw). ... 

Yeh FT, Huang WW, Cheng CC, Na C, Tsay HS. (1994) Tissue culture of Dioscorea doryophora Hance. II Establishment of suspension culture and the measurement of diosgenin content. Chin Agron J 4 257-268. 

Although all the main classes of steroids have now been attained by total synthesis, most drugs are in fact, as noted above, prepared by partial synthesis from natural products that contain the steroid nucleus. The bulk of the world s supply of steroid starting material is derived by differing chemical routes from only two species of plants the Mexican yam, a species of Dioscorea, and the humble soybean. The advantage of using plants rather than valuable domestic animals as raw material is fairly obvious. 

Dimethothiazine, 374 Dimethoxanate, 390 Dimethylpyrindene, 145 Dimethylthiambutene, 106 Dimetridazole, 240 Dinoprost, 27, 33, 34 Dinoprostone, 27, 30, 33, 35 Dioscorea, see Mexican yam Diosgenin, 156, 182 Dioxyline, 349 Diphenhydramine, 41 Diphenidol, 45 Diphenoxylate, 302 Diphenylhydantoin, 246 Di phepanol, 46 Dipipanone, 80 Dipiproverin, 94 Dipyridamole, 428 Displacement, bromine by nitro, 247... 

Wild yam (Dioscorea) Menopause symptoms does not supply progesterone... 

Antischistosomal activity. Hot water extract of the dried rhizome, taken orally by human adults at variable dosage levels, was active. A mixture of Rehmannia glutinosa (Rt), Dioscorea batatas (Tu), Dolichos lablab (Sd), Glycyrrhiza uralensis (Rt), Zingiber officinale (Rh), Evodiarutae carpa (Fr), Atractylodes macrocephala (Rh), and Panax ginseng (Rt) was used . ... 

Isopr. DITERP. cvclized cembranes (pantrop., C 6.1.1.1) STEROIDS norcholestanes diosgenin Dioscorea spp. MI and other Liliales, Ang. AY). 

Production of anthocyanins in plant cell and tissue cultures has been reported for more than 30 species including Daucus carota, Fragaria x ananassa, Vaccinium spp., Vitis hybrida, Solanum tuberosum, Malus sylvestris, Aralia cordata, Perilla frutescens, Ipomoea batatas. Euphorbia millii, Strobilanthes dyeriana. Hibiscus sabariffa, Dioscorea cirrhosa, etc. ... 

Yoshida, K. et al., Structures of alatanin A, B and C isolated from edible purple yam Dioscorea alata, Tetrahedron Lett., 32, 5575, 1991. 

Solanum avicu-lare and Dioscorea deltoidea (S)-(-)-Limonene, (k)-(+)-limonene Carvone [95]... 

Dioscorea batatus Decaisue Shu Yu (Yam) (root) Allantoin, arginine, d-abscisin, mannan, phytic acid, diosgenin, protein, glycosides, triterpene glucosides.48-461-462 Antitumor, sore throat, swelling, food poisoning, goiter, hernia, purulent inflammations. 

Dioscorea bulbifera L. Huang Yao Zi (Potato yam) (rhizome) Saponins, dioscorecin, iodine, dioscoretoxin, saponins, diosgenin, diosbulbin, tannins, campesterol, beta-sotpsterols, stigmasterol, diosbulbines 3348 Treat cancer, goiter. 

Dioscorea cirrhosa L. D. hispida Dennst. D. japonica Thunb. Shu Liang (Dyeing yam) (tuber) Tannins, mucus 33 Hemostatic, increases platelet aggregation, increases uterine contraction. 

Dioscorea nipponica Makino Chuan Shan Long (Japanese yam) (root) Dioscin, diosgenin, trillin, 25 -D- spire sta-3,5 -diene33 -53 Anti-inflammatory, antitussive, expectorant, antiasthmatic. 

Dioscorea opposita Thunb. Shan Yao (Chinese yam) (leaf, tuber, root) Allantoin, arginine, choline, glutamine, leucine, tyrosine, diosgenin, sinodiosgenin.50 Leaf juice for snakebite, root for asthma, cachexia, cough, debility, diarrhea, neurasthenia, polyuria, tuber is anthelmintic. 

---