Researches on the Technology and Bioactive Properties of Phenolic Lipids
Pp. 107-120 (14)
J. H. Tyman
Anacardium occidentale (cashew) containing the principal component phenols, anacardic acid, cardol, 2-methylcardol and cardanol is a unique source of materials useful both for industrial technology, in semi-synthesis and for biological/pharmaceutical applications. Thus, by industrial decarboxylation, anacardic acid in the natural cashew gives predominantly cardanol in the product; technical cashew nutshell liquid (CNSL) together with cardol/2-methylcardol and the cashew kernel is the valuable desired main edible commercial product. Anacardic acid itself together with cardol is best recovered by cold cutting of raw cashew shells followed by solvent extraction to afford natural CNSL. Either from technical or natural CNSL, the individual component phenols, cardanol, anacardic acid, cardol, 2-methylcardol, respectively can be separated by several different techniques notably by phase separation. Each separated component phenol contains saturated, 8(Z)-monoene, 8(Z),11(Z)-diene and 8(Z).11(Z),14-triene constituents. Subsidiary chromatographic separation can give the individual constituents. Technical CNSL without separation is widely used in the production of friction dusts for the automobile industry and in certain polymeric/surface coating applications. Cardanol separated from technical CNSL has uses in semisynthesis, e.g. in the formation of polyethoxylate surfactants, chelatants for metals and for boron. Natural CNSL and anacardic acid separated from it, has potential industrial applications in semi-synthesis and in biological studies. Cardol separated, either from technical or natural CNSL also has potential interest in semi-synthesis, and its homologues, more recently as a potential biological marker.
Centre for Environmental Research, Brunel University, Uxbridge, Middlesex, UB8 3PH, UK.