Mercaptan-Capturing Properties of Mushrooms

Mercaptan-capturing properties of 33 kinds of mushrooms were measured. The mushrooms having a high capturing ability toward methyl mercaptan (MeSH) were Agaricus bisporus, A. campestris, Boletus fraternus, B. subvelutipes, Gyrodon lividus, Leccinum scabrum, Suillus grevillei, Morchella esculenta, Russula nigricans, Hypholoma sublateritium, and Lyophyllum sykosporum. These are liable to change their color when injured. The mixture of their acetone powders, which contain polyphenol oxidases, and phenolic compounds such as tyrosine, γ-l-glutaminyl-4-hydroxybenzene (GHB), DOPA, variegatic acid, grevillin B and C, and pigments, and fluorescent compounds from H. sublateritium also showed high MeSH-capturing properties. 2,5-Bis(methylthio)-DOPA was isolated from the reaction mixture of tyrosine and MeSH with tyrosinase, and the existence of 2- and 5-methylthio-DOPAs was also suggested. Furthermore, acetone powders from fruits and vegetables oxidized the above diphenolic compounds to bind MeSH. Keywords: Enzymatic deodorization; mercaptan capture; mushroom; pigment; acetone powder; bad breath; polyphenolic compound; polyphenol oxidase; methyl mercaptan