Mutation Breeding Of High Tannase Activity Strains From Penicillum And Enzymatic Formation Of Gallic Acid And Quinic Acid

In this dissertation,studies on the enzymatic hydrolysis of tannic acid and qunic acid extracted from Tala tannin in aqueous media and tannase-producing conditions and optimal fermentation parmeters was reported by using Penicillium tannase. Gallic acid is one of important industrial chemicals, and has been used widely and large in amount,becoming now a sold-well commercial in market. Today gallic acid is almost produced from acidic hydrolysis of tannic acid from Chinese gallotannin. But this method has some shortcomings, for example environment pollution. The enzymatic alternative would be practice to slove these problems. Qunic acid is an important medical intermediate. The method that chemically synthesizes qunic acid produces some by-products and makes equipments corroded, etc. In comparison, the enzymatic way has single product and light pollution. It is important to create novel technologies of the enzymatic pre parathion of gallic acid and qunic acid.30 strains Penicillium with higher tannase activity was isolated from natural resource by using enrichment-culture technique on the principle that tannase can be induced by tara tannin. Penicillium No.23 with the capability of hydrolyzing tara tannin and the high biological catalyze activity was selected from these 30 strains on the screening studies of bioconversion of tara tannin into gallic acid and quinic acid by using two-stage fermentation procedure. Penicillium No.23 was mutated by UV treatment, Finally,one strain which was with high tannase activity and stable genetic property was acquired from mutants by means of screening. Its tannase activity has...