| summary(En) : | In this review the author examines works on anti-tyrosinase activity of Artocarpus incisus heartwood and on steroid 5&alpha-reductase inhibitory activity of resveratrol oligomers isolated from Shorea spp. heartwood. The contribution of the 2,4-dihydroxyphenyl structure to the anti-tyrosinase activity is noted. Enzymatic dehydrogenative polymerization of resveratrol yielded 5&alpha-reductase inhibitory oligomers that are structurally related to the natural products of Shorea spp. heartwood. In addition, the author examines studies on hinokitiol (β-thujaplicin), a heartwood constituent of Cupressaceae species exhibiting a variety of bioactivities. Emphasis is placed on its production by Cupressus lusitanica cell cultures, on signal transduction after elicitation, and on the biosynthetic pathway. Cyclic AMP, calcium channel activation, and the jasmonate pathway are proposed to be involved in the multiple signal transduction from fungal elicitor action to the commencement of β-thujaplicin production. It has been proven that β-thujaplicin is biosynthesized from geranyl diphosphate that is formed through the recently found methylerythritol phosphate pathway. Terpinolene is proposed as a precursor, which in turn rearranges to give the seven-member ring of β-thujaplicin, though exact mechanism of the rearrangement is still unknown. |
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