B-Sitosterol

The active constituents in saw palmetto berries are not well defined. Phytosterols (eg, B-sitosterol), aliphatic alcohols, polyprenic compounds, and flavonoids are all present. Marketed preparations are dried lipophilic extracts that are generally standardized to contain 85-95% fatty acids and sterols. 

Fig. 5.4.4a Methyl ester-trimethylsilyl (TMS) ethers of BAs from a plasma sample, b n-Butyl ester-TMS ethers of BAs from a plasma sample (adapted from [15]). 1 Nor-cholic acid, 2 litho-cholic acid, 3 deoxycholic acid, 4 chenodeoxycholic acid, 5 cholic acid, 6 ursodeoxycholic acid, a cholesterol, b sitosterol)...

Fig. 8.5 Chemical structures of EDCs (a) bisphenol-A (b) triclosan (c) nonylphenol (d) 17b-estradiol (e) genistein (f) b-sitosterol...

B-Sitosterol - Recent reports demonstrated the efficacy of P-sitosterol in lowering plasma LDL-C in patients with Type II hyperlipoproteinemia. "" 3-Sitosterol obtained from tall oil was found to be effective at 3 g/day, a dose substantially lower than that required with older preparations. However, in juvenile Type II hyperlipoproteinemia, 3-sitosterol lowered LDL-C by only 6% but, in addition, decreased HDL-C by 15% thus, 3-sitosterol was not recommended for the treatment of hypercholesterolemia in children." A potential problem with 3-sitosterol is the increased risk of gallstone formation, in view of the finding of Increased saturation index of bile in patients given 3 g/day of plant sterols. ... 

The organic chemistry of this study focused on some of the most coimnon sterols in soils, i.e., cholesterol, 24-ethylcoprostanol, stigmasterol, campesterol, and b-sitosterol. 24-Ethylcoprostanol has been used as biomarker for (nonhuman) herbivore fecal matter. Results of the BC/MS analysis of one of the sediment samples is shown in Fig. 6.26 and the presence of these sterols clearly identified. This sample is taken from the stable area and clearly shows the presence of coprostanol and 24-ethylcoprostanol indicating enrichment by fecal material from herbivores. 

In addition to resin acids, rosin contains neutral materials and oxidized impurities. Tall oil rosin contains about 1-5% fatty acid and small amounts of sulfur compounds and phenolics. In tall oil pitch, which is the bottom fraction in the tall oil distillation process, besides residual amounts of rosin and fatty acids, a substantial amount of unsaponifiable matters has been identified and recovered as B-sitosterol (30). Gum rosin contains large amounts of neutrals that contribute to the typical odor and reduce its tendency to crystallize. The amount of neutral materials present in a rosin largely depends upon the location where the raw material originates and its processing conditions. 

Identification of B-Sitosterol, Campesterol and Stigmasterol in Human Serum... 

Plant sterols - especially B-sitosterol, given at the dose of 10-15g/day - are known to reduce serum cholesterol levels by inhibiting cholesterol absorption[137,138]. This effect could be due either to competitive inhibition for mucosal uptake or to crystallization and coprecipitation of the sterols or to other unknown mechanisms. Mattson et al. recently showed that when 3-sitosterol was dissolved in the test meal together with cholesterol - so that both the sterols were presented simultaneously to the intestinal mucosa a much smaller amount of the plant sterol (Ig) was sufficient to induce a significant (42% on average) decrease of cholesterol absorption[139]. If confirmed, these findings might render much easier the use of phytosterols in the treatment of hypercholesterolemia. 

Matseshe, Effect of B-sitosterol alone or in combination with chenic acid on cholesterol saturation of bile and cholesterol absorption in gallstone patients. Gastroenterology, 76 1341-1346 (1979). 

Nweze, N. E., Anene, B. M. Asuzu, I. U. (2011). In vitro anti-trypanosomal activities of crude extracts, b-sitosterol and a-sulphur from Buchholzia coriacea seed. AJr. J. Biotechnol, 10,15626-15632. 

A number of mono- and oligosaccharides bound to plant lipids have been described. In particular, steryl glucosides (SG) and acylated steryl glucosides (ASG) were found in all plant tissues [1-3]. Kleinig Kopp [4] showed, by radiolabelling of carrot cultures, that SG and ASG represent 0.8 and 1.0 percent, respectively, of carrot membrane lipids. However, relatively little is known on pentose-containing plant glycolipids. A B-sitosterol xyloside (SX) was chemically characterized in Bauhinia candicans [5] and the in vitro formation of pentosyl derivatives has been reported in pea [6]. 

Genistein, B-sitosterol, ITamethyltestosterone, 11-ketotestosterone, isoflavonoids, lignans, zearalenone, coumestrol... 

---