P-Sitosterol

In milk fat, cholesterol is associated with Hpoproteins in the milk fat globule. It is also a component of animal membranes and controls rigidity and permeabihty of the membranes. Cholesterol has interesting surface properties and can occur in Hquid crystalline forms. Plants contain sterols such as P-sitosterol [83-46-5] (4b) or stigmasterol [83-48-7] (4c). Their functions in plant metaboHsm are not yet well understood. Analysis of sterols has proven useful for detection of adulteration of edible fats (9). 

Bacterial removal of sterol side chains is carried out by a stepwise P-oxidation, whereas the degradation of the perhydrocyclopentanophenanthrene nucleus is prevented by metaboHc inhibitors (54), chemical modification of the nucleus (55), or the use of bacterial mutants (11,56). P-Sitosterol [83-46-5] (10), a plant sterol, has been used as a raw material for the preparation of 4-androstene-3,17-dione [63-05-8] (13) and related compounds using selected mutants of the P-sitosterol-degrading bacteria (57) (Fig. 2). 

Oil CAS Registry Campesteiot Number [474-62-4] Stigmasterol [83-48-7] p-Sitosterol [83-46-5] A -Avenasterol A -Stigmasterol [83-45-4]... 

Processing Raw Materials. Along with the aforementioned chemical methods of processing steroid raw materials, microbial transformations have been and are used in a number of commercial degradation processes. The microbial degradation of the C17 side chain of the two most common sterols, cholesterol (2) and P-sitosterol (41), is a principal commercial method for the preparation of starting materials in Japan and the... 

The rate of side-chain cleavage of sterols is limited by the low solubiUty of substrates and products and thek low transport rates to and from cells. Cyclodextrins have been used to increase the solubiUties of these compounds and to assist in thek cellular transport. Cyclodextrins increase the rate and selectivity of side-chain cleavage of both cholesterol and P-sitosterol with no effect on cell growth. Optimal conditions have resulted in enhancement of molar yields of androsta-l,4-diene-3,17-dione (92) from 35—40% to >80% in the presence of cyclodextrins (120,145,146,155). 

Other organic raw materials P-Sitosterol Lanolin, wool wax, cotton seed, wheat germ oil... 

Lipids, e.g. P-sitosterol, geraniol, dolichol, squalene, cholesterol 200 °C, 15 min Induced fluorescence detection limits <1 gg cholesterol. [3]... 

Sterols are minor constituents of most fats. Those of animal origin contain cholesterol and traces of other sterols, whereas plants contain phytosterols, of which p-sitosterol is the most common. Sterols occur in the free form or, after esterification to fatty acids through the 3-OH group, as steryl esters. The presence of sterols in archaeological residues can be a useful indicator of a plant or animal origin or an indicator of both if cholesterol and phytosterols are detected in the same sample. That noted, cholesterol is a potential contaminant of all archaeological samples subjected to handling. 

Nakamura, Y., Yoshikawa, N., Hiroki, L, Sato, K., Ohtsuki, K., Chang, C. C., Upham, B. L., and Trosko, J. E. (2005). P-Sitosterol from psyllium seed husk (Plantago ovata Forsk)... 

Radioactivity distribution. The N-hexane lipido/sterolic extract (LSESr) supplemented with [ C]-labeled oleic or lauric acids or P-sitosterol was administered orally to rats. The highest level of radioactivity uptake was LSESr supplemented with [ C]-labeled oleic acid. Ratios of radioactivity in tissues compared to plasma showed an uptake of radioactivity greater in prostate as compared with other genital organs, i.e., the seminal vesicles or to other organs such as... 

Arata, Y. and H. Matsuda. 1961. Constituents of Rhizoma nupharis. XVII. Isolation of P-sitosterol, palmitic acid, and oleic acid. Kanazawa Daigaku Yakugakubu Kenyu Nempo 10 35-39. 

Licania pyrifolia Grisebach is a small tree widely cultivated in the Amazonian regions of Venezuela for their edible fruits called merecure . The chloroform extract yielded a-amyrin, P-sitosterol, lupeol, betulin,... 

Aloctins, campesterol, P-sitosterol, and acemannan have anti-inflammatory properties. 

The sterol cholesterol (Fig. 2b) is a major constituent of animal plasma membranes but is absent from prokaryotes. The fused ring system of cholesterol means that it is more rigid than other membrane lipids. As well as being an important component of membranes, cholesterol is the metabolic precursor of the steroid hormones (see Topic K5). Plants contain little cholesterol but have instead a number of other sterols, mainly stigmasterol and P-sitosterol which differ from cholesterol only in their aliphatic side chains. 

P-Sitosterol and sitostanol Many plants Hypocholesterolemic Gylling and Miettinen (1996)... 

P-Sitosterol-3-O-P-D- glucoside (phytosterol glycoside) Widespread Caryophyllus Jlos (Myrtaceae) PEP (48 pM) [118]... 

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