[Screening and identification of a fungal strain functioning in hydroxylation of puerarin].

ABSTRACT

OBJECTIVE: Puerarin is a Chinese herbal medicine. We isolated a fungus from soil which could convert puerarin to 3'-hydroxypuerarin. METHODS: Strains were cultivated on potato dextrose agar (PDA). The biotransformation product was extracted with an organic solvent and detected on high performance liquid chromatography(HPLC). RESULTS: A total of 186 fungal strains were isolated from soil, and strain NT-01 was determined to transform puerarin into 3'-hydroxypuerarin. The product was identified as 3'-hydroxypuerarin by MS and 1H-NMR and 13C-NMR. The morphology characteristic of strain NT-01 was consistent with Gliocladium deliguescens. Phylogenic analysis on sequences showed that strain NT-01 was clustered together with G. deliguescens and G. viride with high boostrap supporting, so that strain NT-01 was identified as Gliocladium sp. CONCLUSION: Gliocladium strain NT-01 can convert puerarin to 3'-hydroxypuerarin.