Bioactive Lipid-soluble Constituents

The neurological effects of kava are attributed to a group of substituted dihydropyrones called kava lactones (1). The main bioactive constituents include yangonin, desmethoxyyangonin, 11-methoxyyangonin, kavain (kawain), dihydrokavain, methysticin, dihydromethysticin, and 5,6-dehydromethysticin (8). It is believed that the components present in the lipid-soluble kava extract, or kava resin, are responsible for the central nervous system (CNS) activities of kava including sedation, hypnosis, analgesia, and muscle relaxation (9). Aqueous kava extract was not active orally in mice or rats. 

Possible Mechanism of Allelopathlc Action of Water-Insoluble Plant Lipids. Many non-polar natural products with germination and growth regulation activities In laboratory tests are In pure form not sufficiently water soluble to account for their allelopathlc activities observed In the field. For this reason the notion exists that sterols and other non-polar plant constituents are not likely to play a role In allelopathlc actions, and It Is generally concluded that the bioactivity data observed In the laboratory are therefore coincidental. 

Hazelnut, which contains lipid-lowering bioactives such as MUFA, PUFA, phytosterols, phytostanols, polyphenols, and sphingolipids [11,12,107,117,140,141,147,175,183,189,203-205], offers an opportunity as a potential hypercholesterolemic heart-healthy diet component In addition to these bioactives and minor components, there are a number of nonfat constituents (such as essential minerals, essential amino acids, antioxidant phenoUcs, soluble dietary fiber, and phytochemicals, among others) in hazelnut that may elicit additional cholesterol-lowering and cardioprotective effects [11,57,59,85,117,174,206]. 

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