A7-Stigmasterol

Values for it are listed by the AOCS (1997), which indicates that campesterol is high at 25-30%, stigmasterol is absent, and high levels of A5-avenosterol and 24-methylene cholesterol are present however, a source is not given for these values and they should be confirmed. This publication also lists blackcurrant seed oil as containing 7.2-10.4% campesterol 0.5-1.0% stigmasterol 70-85% (3-sitosterol 2-5% A5-avenosterol 0.5—4.5% A7-stigmasterol and 0.4-2% A7-avenasterol. 

Oil campesterol stigmasterol p-sitosterol sitostanol A5-avenasterol A7-stigmasterol A7-avenasterol ref... 

The sterol composition of both oils is compared in Table 12. Clearly, for HOSO, p-sitosterol is the sterol with the highest occurrence (42-70% of total sterols), followed by A7-stigmasterol (6.5-24%), campesterol (5-13%), and stigmasterol (4.5-13%). Although there are differences in the sterol composition of both oils, they are not large enough to enable easy analysis. 

Peanuts contain -sitosterol, campesterol, stigmasterol, A5-avenasterol, A7-stigmasterol, A7-avenasterol, andbrassicasterol (Table 8.6). These sterols, which are secondary alcohols with 27-29 carbon atoms, are crystalline solids at room temperature. (i-Sitosterol, the major component in peanut sterols, has been shown to inhibit cancer growth (Awad el al. 2000) and may offer protection from colon, prostate and breast cancer. Unrefined peanut oil contains approximately... 

Oil Campesterol Stigmasterol (j-Sitosterol Sitostanol A5-Avenasterol A7-Stigmasterol A7-Avenasterol Reference... 

Oil CAS Registry Number Campesterolb [474-62-4] StigmasterolC [83-48-7] P-Sitosterol K 3-46-51 A5-Avenasterol A7-Stigmasterol [83 45-4]... 

Other minor components characterized include tocopherols (90 mg/kg), triterpenol alcohols and cinnamic acid esters, sterols and 4-methylsterols. These are characteristic of the oil (Derbesy and Richert, 1979 Peers, 1977 Itoh et al, 1974). The major triterpene alcohols are a- and jS-amyrin, butyrospermol and lupeol. The major sterols are a-spinasterol, previously confused with )8-sito-sterol and A7-stigmasterol (Derbesy and Richert, 1979 Itoh era/., 1974). (Tables 3.145-3.147). 

Of the various pure reference sterols, solutions of 20 g/1 are prepared in diethyl ether or in another suitable solvent. The relative retention distances (or times) of the various sterols compared with cholesterol are normally within the following ranges cholesterol, 1.00 brassicasterol, 1.13-1.15 campesterol, 1.32-1.34 stigmasterol, 1.44-1.46 /3-sitosterol, 1.66-1.68 A7-stigmasterol, 1.85-1.95. 

Oil/fat Cholesterol Brassicasterol Campesterol Stigmasterol Sitosterol A5-avenasterol A7-stigmastenol A7-avenasterol Others Total (mg/kg)... 

Sum of A5-avenasterol A7-avenasterol and A5-stigmasterol. Sum of free and esterified sterols. 

Plant sterols, also called phytosterols, have been reported to include over 250 different sterols and related compounds in various terrestrial and marine materials (Akihisa et al., 1991). Sitosterol, stigmasterol, and campesterol are the commonly consumed plant sterols. The predominant sterol class in vegetable oils is 4-desmethyl sterols. Sitosterol usually contributes more than 50% of desmethyl sterols. The other most significant desmethyl sterols include campesterol, stigmasterol, A5-avenasterol, A7-avenasterol, and A7-stigmastenol. Brassicasterol is a typical sterol for rapeseed and other Cruciferae. Stanol occurs in significant amounts in com bran and fiber oil (Piironen, et al., 2000). 

Desmethyl sterols Sample Cholesterol Campesterol Stigmasterol Sitosterol A5-Avenasterol A7-Stigmastenol A7-Avenasterol... 

Sterols include 4oc-methylsterols, intermediates of sterols and triterpens biosynthesis. Analysis of the sterol fraction demostrated the constant presence of P-sitosterol, campesterol and stigmasterol, A5-avenasterol, while A7-avenasterol may be absent or present in very low amount, p-sitosterol makes up the 75-90% of the total sterol fraction, the rest of sterols occur in minute quantities. 

In stigmasterol-supplemented cultures (Table III), N.N-dimethyldodecanamine caused the accumulation of a number of and A 2,24 sterols, including the 22,24 analogue of fucosterol stigmasta-5,22E,24(28)-trienol. Presence of this compound and lack of detection of fucosterol and 5,22, a5,7,22 or A7,22 dealkylated sterols... 

Numerous phytosterols have been isolated from the unsaponifiable fraction of VOO the most important are 3-sitosterol, A5-avenasterol, and campesterol. Several other minor compounds, such as cholesterol, stigmasterol, clerosterol, A7-stigmastenol, and A7-avenasterol have also been found in VOOs [73,74]. Their structures can be seen in Figure 9.6. 

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