Inaoside A: New antioxidant phenolic compound from the edible mushroom Laetiporus cremeiporus
Atsushi Kawamura,
Aira Mizuno,
Mayuri Kurakake,
Akiyoshi Yamada,
Hidefumi Makabe
Affiliations
Atsushi Kawamura
Department of Biomolecular Innovation, Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, Kami-ina, Nagano, 399- 4598, Japan; Corresponding author. Department of Biomolecular Innovation, Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, Kami-ina, Nagano, 399- 4598, Japan.
Aira Mizuno
Department of Agriculture, Graduate School of Science and Technology, Shinshu University, Kami-ina, Nagano, 399-4598, Japan
Mayuri Kurakake
Department of Agriculture, Graduate School of Science and Technology, Shinshu University, Kami-ina, Nagano, 399-4598, Japan
Akiyoshi Yamada
Department of Agriculture, Graduate School of Science and Technology, Shinshu University, Kami-ina, Nagano, 399-4598, Japan; Department of Mountain Ecosystem, Institute for Mountain Science, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, Kami-ina, Nagano, 399- 4598, Japan
Hidefumi Makabe
Department of Biomolecular Innovation, Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, Kami-ina, Nagano, 399- 4598, Japan; Department of Agriculture, Graduate School of Science and Technology, Shinshu University, Kami-ina, Nagano, 399-4598, Japan; Corresponding author. Department of Biomolecular Innovation, Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, Kami-ina, Nagano, 399- 4598, Japan.
Laetiporus cremeiporus is the edible mushroom distributed in East Asia. It has been reported that an extract of L. cremeiporus exhibited DPPH radical scavenging activity. The aim of this study is to identify the antioxidant compound from L. cremeiporus. Guided by DPPH radical scavenging activity, a new antioxidant phenolic compound inaoside A (1) and three well-known bioactive compounds 5′-S-methyl-5′-thioadenosine (MTA, 2), nicotinamide (3), and adenosine (4) were isolated from L. cremeiporus. An antioxidant compound was isolated from L. cremeiporus for the first time. This is the first report of the isolation of 1, 2, and 4 from L. cremeiporus. The structures were determined by one- and two-dimensional NMR spectroscopic analysis and chemical derivatization. The antioxidant activities of extracts, fractions, and isolated compounds were evaluated by a DPPH radical scavenging assay. Compound 1 exhibited significant DPPH radical scavenging activity (80 % inhibition at 100 μg/mL, IC50 79.9 μM, trolox equivalent antioxidant capacity (TEAC) = 0.36).
