研究業績

Hericium erinaceus is an edible and medicinal mushroom. Previously, we found hericenones C–H from the fruiting bodies and erinacines A–I from the mycelia of the fungus. These compounds stimulated nerve growth factor (NGF) synthesis both in vitro and in vivo; some have been suggested to be effective in the prevention and treatment of dementia. Recently, the total synthesis of hericenones C–H and their derivatives (1–4) was reported by one of the authors. We considered that the chemical synthetic route would also be reasonable as a biosynthetic pathway of the compounds. Based on the hypothesis, we investigated the endogenous existence of synthetic intermediates and products of the chemical synthesis in the fruiting bodies. The n-hexane-soluble part of the fruiting bodies of H. erinaceus was fractionated, and all the fractions were subjected to a product ion scan and multiple reaction monitoring (MRM) analysis by LC-MS/MS and compared to the authentic synthesized compounds. The analysis indicated the endogenous existence of 1–4 and the dehydrated form of 2 or 3. The dehydrated form was elucidated to be (Z)-5 by chemical synthesis, and a plausible biosynthetic pathway was proposed.