Sources of Steroids

Historically, this lack of competition is probably responsible for the flies total dependency on the cactus The flies somehow lost the biochemical machinery needed for conversion of common plant steroids into those steroids they require. The loss went unnoticed, because the cactus provided an assured source of steroids the flies were still able to utilize. However, no other available plants provide these unusual steroids, so they must now consume senita cactus to survive. 

Raw Materials and Extraction. The variety of natural sources of steroid raw materials is vast, and the exact details of manufacturing processes are ambiguous closely held industrial secrets. However, the most widely utilized raw materials for die partial synthesis of steroids appear to be the following (/) the sapogenins, for example, diosgenin (27). (2) the sir-ucliirally relaied sierold alkaloids, (3) sterols, such as cholesterol (8), and (4) bile acids. 

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. 

Ox bile, which contains cholic acid as its principal constituent, provided one of the earliest mammalian sources of steroid raw materials for the commercial manufacture of the androgens. In nature, cholesterol itself is the mammalian precursor of the androgens, the biosynthesis passing through progesterone (XII). 

TABLE 4. Principal Commercial Sources of Steroid Raw Materials from Plants... 

The success of the multinationals in exploiting alternative steroid sources exposed the limitations of the wild yam. Yams were laboriously dug from the ground exclusively for those involved in the manufacture of steroids. In contrast, all the other plant sources of steroids identified in Table 4 were harvested for other industries these industries generally regarded the steroid-containing waste as worthless to them. 

The adrenal glands are located anatomically above the kidneys. They comprise a three-layer cortex and a medulla. The medulla is the source of catecholamines such as epinephrine, the fight-or-flight hormone. The cortex is the source of aldosterone, the primary mineralocorticoid that is involved in the regulation of sodium reabsorption in the kidneys. In addition, the cortex is also the source of steroids known as glucocorticoids, of which cortisol is the principal endogenous representative. Synthesis and release of cortisol is under the control of adrenocorticotropic hormone (ACTH). 

Adipocytes are also a significant source of steroid hormones, including cortisol, andro-... 

Because of the economic importance of sapogenins as a source of steroids, and in spite of the failure to find new methods to improve on Marker s original procedure for side-chain degradation, some work still continues in this area. 

Enzyme-catalysed desulfuration of steroids plays an important role in steroid biosynthesis and may provide a source of steroids in the growth and proliferation of breast cancer. Inhibition studies of estrone sulfatase with both steroidal and non-steroidal phosphate compounds have now shown that the best inhibitors contain phosphate mono anions and that the basic structure for inhibition does not require the steroid nucleus. ... 

Abstract—Liliaceae is a rich source of steroidal glycosides. About 400 of new glycosides including triterpene glycosides and several staroidal alkaloids have been isolated and thdr structures were elucidated by our systematic studies on chemical constituents of Liliaceae plants. Some of these glycoades have unique structures. 

Though the plants of Allioideae are known to contain sulphur compounds, we have found out from our studies that the plants of this subfamily are also a rich source of steroidal glycosides. 

Several arthropods are rich sources of steroidal defensive compounds. These progestagens are particularly common in water beetles of the subfamilies Colymbetinae and Dytisci-nae. Beetles of these families accumulate steroidal toxins as... 

Although names and properties of thousands of hydrocarbons and their variously oxidized and rearranged derivatives have been compiled and catalogued (variously complete catalogues that are incomplete when published), the exact number of terpenes (Cio), sesquiterpenes (C15), diterpenes (C20), sesterpenes (C25), triterpenes (C30), carotenoids (C40), and varieties of rubber (e.g., laytex and gutta-percha) is unknown. Similarly, tomes have been written on the subject, and the discussion of these compounds here will end with an introduction to the triterpenes because these serve as sources of steroids (animal) and sterols (plants). 

Yamogenin and yamogenin isomer diosgenin, (25J )-spirost-5-en-3P-ol (10-64) are the aglycones of saponins in yams Dioscorea spp., Dioscoraceae) whose starchy tubers are eaten in Africa, Southeast Asia and the Pacific region (D. alata and D. escuknta in Southeast Asia, D. trifida in South America, D. rotundata and D. cayenensis in West Africa). Yams typically contain 4-8% saponins, which are also a source of steroids for the pharmaceutical industry. 

Protecting groups, as described in the text, are essential parts of many organic syntheses. An example is the synthesis of the sex hormone testosterone (Section 4-7) from a cholesterol-derived starting material. Natural sources of steroid hormones are far too limited to meet the needs of medicine and research these molecules must be synthesized. In our case, the hydroxy function at C3 and carbonyl function at C17 of the starting mat al have to trade places to furnish the desired testosterone precursor. In other words, selective reduction of the carbonyl group at C17 and oxidation of the hydroxy group at C3 are required. In the scheme that was... 

All commercial types and the hydrogenated version, as well as the waxy alcohols obtained by - hydrolysis, are used in - cosmetics, leather polishes, temporary - corrosion protection lubricants and - pharmaceutical applications. L. serves also as a source of - steroids. 

Medrysone, fluorometholone and tetra-hydroxytriamcinolone have been shown to have topical anti-inflammatory effects with a reduced propensity to increase lOP. Methyl-prednisolone acetate provides a source of steroid that lasts for up to 2 weeks. 

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