Optimization Of Solid-state Fermentation Parameters Of Corn Gluten Meal And The Effect Of Antioxidant Capacity Of Products On Broilers

CGM is by-product of producing corn amylum with rich resource and nutrition. It is lack of diaminocaproic acid and 2-amino-3-indole-propionic acid which are necessary amino acids to people,and has higher alcohol-soluble protein content. Therefore, the feeding value was severely restricted. CGM was degradated by microbial to produce polypeptide corn of good solubility and biological activity.The optimal process parameter of mixed microbial degradating CGM by solid-state fermentation is carried out in the first part, and the quality of the product was determined. The culture time was determined by drawing the four strains of the growth curve, and they are Aspergillus niger, Lactobacillus, yeast, and Bacillus licheniformis for 28 h, 24 h, 32 h and 28 h respectively; By single factor experiment and L9(34) orthogonal test, each fermentation condition of CGM was optimized. And Aspergillus niger fermentation conditions were determined finally: 40% moisture content, initial pH 7, 84 hours of fermentation at 32 ℃, and the resulting polypeptide product yield is 32.14%; Lactic acid fermentation conditions were as follows: 45% moisture content, initial pH 4.5, 84 hours of fermentation at 37 ℃, and the resulting polypeptide product yield is 26.33%; Yeast fermentation conditions are as follows: 45% moisture content, initial pH5.5, 84 hours of fermentation at 31 ℃, and the resulting polypeptide product yield is 25.79%; Bacillus fermentation conditions are as follows: 45% moisture content, initial pH 6, 72 hours of fermentation at 38 ℃, and the resulting polypeptide product yield is 26.37%; This four strains had no antagonistic effect on each other by countermeaure test,and were inoculated with mixed fermentation: 4 %Bacillus licheniformis, 4 % lactic acid bacteria, 6%yeasts, and 6% Aspergillus niger respectively. Orthogonal experiment was used to optimize the fermentation and to determine the mixed fermentation conditions: 40% water content, initial pH of 7, 84 hours of fermentation at 33 ℃. Under these conditions, crude protein content, polypeptide yield, content of total sugar and reducing sugar, amino acid composition and content of the fermentation product were determined.The second part was the effect of dietary fermentation product of CGM on growth performance of intestinal flora and antioxidant capacity of broilers. The 150 healthy 7-day-old broilers were randomly divided into three groups, control, A and B, each with 10 replicates of five broilers. They were fed basal diet, 5% and 10% of the amount of the diet in different groups. The results showed that: added fermented CGM diet had no significant effect on the results of ADFI and ADG(P>0.05); but the F/G in the test groups was reduced. 10% addtion had significant effect on the liver(P<0.05), kidney and thymus(P <0.01), and certain effect on other visceral parameters(P>0.05); the number of harmful bacteria in the gut was reduced, especially E. coli(P <0.05); the number of bacteria was increased, especially Lactobacillus(P<0.01); After measuring the T-SOD、GSH-Px、BUN、MDA、protein and albumin concentration in the body’s serum, the MDA in the liver(P<0.01)and the BUN, MDA and protein content in the body’s serum(P<0.05)is reduced; T-SOD vitality in the liver was increased significantly(P<0.01); the ability to clear hydroxy radical and superoxide free radical of serum was increased significantly(P<0.01).