Abstract: In order to produce baicalein from baicalin by biotransformation method,a microbial strains was isolated from mouldy roots of fresh Scutellaria baicalensis Georgi,then the product was analysis and the strain was identified.After enriching strains from mouldy roots of fresh and clean Scutellaria baicalensis Georgi exposed to indoor air for days,culture medium contained only Radix scutellariae powder was applied to screen stains.Then they were seperated on PDA plates and the single colonies were inoculated into PDB contained 0.1% baicalin respectively.The biotransfomation products were idenified and quantified by HPLC and then a fungi strain RM3 that effectively transformed baicalin to baicalein was gained.The strain transformed baicalin to baicalein in PDB at 28 ℃,150 rpm with a molar yield of 83.87% in 5 d.It was inditified as Penicillium sp.RM3 by morphologic characters,microscopic morphology and ITS sequence analysis.This strain biotransformed baicalin to baicalein effectively,clean and green,therefore alleviating the pressure of traditional medicinal resources and meeting the market and clinical needs.It was sure to be a very promising microbial strain to produce Baicalein.

Key words: baicalin, baicalein, biotransformation, Penicillium sp.RM3