Abstract: One Rhizopus species P78 which could produce starch degradation enzymes was isolated from soil sample near starch plant. A Rhizplus species mutant PE - 8 a starch degradation enzyme was obtained after the Rhizopus species P78 was treated by U. V., Co60ray. The enzyme activity reached 3000U /g (dry basis) when it was nurtured in wheat bran medium at 46 -48℃ after 22 ~ 24 hours. The starch hydrolyzate formed by the catalysis of the enzymes produced by Rhizopus species mutant PE - 8 was analysed by high performance liquid chromatogra-phy and paper chromatography. The results indicated the percentages of oliosaccharide (G3 - G8) to total sugar of the sample analysed reached 77. 6% , while glucose was only 3. 03% . It was reasoned that the sample analysed was a type of oligosaccharide. For this reason, the enzyme produced by the Rhizopus species mutant PE - 8 belonged to oligosaccharidase.

Key words: Rhizopus species , Screening , Oligosaecharide , Oligosaccgaridase