Study On Processing Technology Of α-transglucosidase

α-transglucosidases is a critical enzyme of producing isomaltooligosaccharide，butit has not achieved industrialized production yet in domestic. To the present, we have toimport α-transglucosidases for isomaltooligosaccharide production from abroad, whichmakes the key technology controlled by foreign countries and make it at a highprice.Now many researchers have focused on the study of α-transglucosidases,but westill have difficulties.First,the strains screened from the nature environment have a lowyield of α-transglucosidases,which makes it difficult to industrializedproduction.Second, the α-transglucosidases produced by E.coli builded by geneticengineering technology are generally intracellular, and the extraction process forintracellular enzyme is more complex and its activity recovery is low, which is notconducive to the industrialized production.The preparation and immobilization technique of transglucosidases belongs to thefield of enzyme engineering and fermentation engineering.In this paper, a strain ofAspergillus niger was screened from environment, which can produce extracellulartransglucosidases.After mutagenesis and optimization a mutant was got namedAspergillus niger BLB-28. As a result, the yield of α-transglucosidases was increased.Transglucosidase solution was prepared after fermentation, ultrafiltration sterilizationand concentration.Then the α-transglucosidases was immobilized by the resinadsorption-sodium alginate-glutaraldehyde cross-linking method.The immobilizationtechnique of transglucosidases make the enzyme can be used efficiently andcyclically.This technique has not only greatly improved the situation that domestictransglucosidase was subject to international market,but also able to significantly reducethe cost of the use of enzymes in the production of isomaltooligosaccharide. Comparedwith imported enzyme,the immobilized transglucosidases can reduce the cost about300-400yuan.The immobilized transglucosidases in this study is mainly used to produceisomaltooligosaccharide and it can be applied in many field,such as food,medicine, feedand other industrial fields.