Biotransformation of l‐menthol by soil‐borne plant pathogenic fungi (Rhizoctonia solani)

Abstract

AbstractThe biotransformation of l‐menthol was investigated by using nine isolates of Rhizoctonia solani (AG‐1‐IA Rs24, Joichi‐2, RRG97‐1; AG‐1‐IB TR22, R147, 110.4; AG‐1‐IC F‐1, F‐4 and P‐1) as a biocatalyst. In the cases of Rhizoctonia solani F‐1, F‐4 and P‐1, almost all of the substrate was consumed in 3 days and the major metabolite increased rapidly for the first of 3 days incubation. The structure of the major metabolite was elucidated on the basis of its spectral data. The major metabolite was determined to be (−)‐(1S,3R,4S,6S)‐6‐hydroxymenthol which indicated that l‐menthol was hydroxylated at the C‐6 position. From the main component analysis, the nine isolates of Rhizoctonia solani were divided into two groups based on their ability to transform l‐menthol to (−)‐(1S,3R,4S,6S)‐6‐hydroxymenthol. This is the first report on the biotransformation of l‐menthol by Rhizoctonia solani.© 2001 Society of Chemical Industry