Study On Microbial Enzymatic Preparation Of Corn Peptide

The Corn Gluten Meal(CGM) is the byproduct in corn amylun production.The 50-70 percent of CGM is protein.The corn peptides have special physiological functions,which are producted by the enzymatic hydrolysate of corn gluten meal.These including favourable absorbability,inoxidizability,antifatigue effect.Some kinds of corn peptides can also reduce the concentration of bloodammonia,lower blood pressure ,promote ethanol metabolism.Therefore the study of corn peptides preparation get enormous attention.In this work, we carry out an investigation with microbial fermention techonology on the enzymolysis of the corn gluten meal(CGM). One bacterial strain was isolated from soil ,and named 0709.Based on polyphisic studies, including its morphology,physiological characteristics chemotaxonomy and 16S rDNA sequence analysis,it was Bacillus cereus sp.0709.By the single facter experiments and orthogonal experiments,the optimum condition of excreting protease was determined.fermentional time was 54h,the optimum temperature for fermention was about 40℃,pH was about 7.0. Vaccination quantity is 300ml.Three methods were adopted into the enzymolysis of CGM. Comparing the enzymolysis situation about alacase and fermentional solution .It was suggested that the third method which add 1% Nacl into reactional solution was good for protease in the fermentional solution.The protease was purified from the cell free supernatant by ammonium sulfate precipitation ,iron exchange chromatography and gel filtration chromatography.SDS-PAGE analyses revealed two bands of 21kda and 32kda.