Rice bran squalene

Squalene Vegetable oil, olive oil, rice bran oil Myrtenol Myrtus cuninus... 

Squalene is an isoprenoid compound that is found in large quantities in shark liver and in smaller quantities in olives, rice bran and wheat germ. It is a bactericidal compound and an antioxidant and it aids in skin nutrition. Several cosmetic applications of rice bran and rice bran oil arise from the biological effects of their squalene, vitamin E and y-oryzanol content. Since these compounds are fat-soluble, rice bran oil is used for all these preparations. 

Major flaxseed sterols are stigmasterol, camp sterol, and 5-5 avenasterol (Daun et al., 2003). Obtusifoliol, gramisterol, and citrostadienol constituted 45%, 22%, and 12%, respectively, of the total 4a-monomethylsterol in flaxseed (Kamm et al., 2001). Squalene content of flaxseed oil was reported as 4 mg/100 g oil, which was significantly lower than olive, corn, and rice bran oils. Squalene content is an intermediate compound of biosynthesis of plant sterols, which may have protective effects on lipid quality. Squalene could act as a peroxy radical scavengers in high polyunsaturated fatty acid oil (Dessi et al., 2002). 

Lipases liberated from the testa and the cross cells promote rapid hydrolysis of the oil, and therefore, it should be extracted within hours of milling. Attempts have been made to upgrade oil with 30% free acid by reaction with glycerol and the enzyme Lipozyme Mucor miehei lipase) followed by neutralization. The major acids in rice bran oil are palmitic (12-18%, typically 16%) oleic (40-50%, typically 42%), and linoleic acid (29 2%, typically 37%). The oil contains phospholipids ( 5%), a wax that may be removed and finds industrial use, and unsaponifiable matter including sterols, 4-methylsterols, triterpene alcohols, tocopherols, and squalene among others. 

Supercritical CO2 column fractionation of soybean (57, 86, 88, 89) and rice bran oil (57) deodorizer distillates has been investigated to enrich their sterol and tocopherol contents. Brunner et al. (89) reported that the FFA were enriched in the top (in the extract), whereas the monoacylglycerols, tocopherols, and diacylglycerols were enriched in the bottom (in the raffinate) fraction during the fractionation of soybean oil deodorizer distillate. Saure and Brunner (88) achieved a tocopherol concentration of more than 70% (w/w) using continuous column fractionation of soybean deodorizer distillate where squalene was almost completely found in the top product, whereas sterols and tocopherols were enriched in the bottom product. King and Dunford (57) developed a two-step column fractionation scheme (13.6 MPa and 27.2 MPa at 313 K) for the enrichment of phytosterols from soybean and rice bran oil deodorizer distillates such that the FFA were removed in the first step and sterols were enriched in the oil fraction in the second step. 

The byproducts of rice-bran oil refining include waxes, lecithin, soap-stock (containing high-value oryzanol), and deodoriser distillate containing sterols, tocopherols, tocotrienols and squalene. The characteristics and physical properties of purified rice wax are similar to camauba wax (Sayre and Saunders... 

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