The Screening Of Animal Source Of Probiotics With High Enzyme Activity

This study is screening of high activity cellulase-producing bacteria, protease-producing bacteria, amylase-producing bacteria from rumen contents of cattle or sheep.And use cellulase, protease and amylase as the main product to optimization the medium components and fermentation conditions of the corresponding bacteria comprehensively,in order to obtain the optimum fermentation conditions,provided some technical reference for feed additives and industrial production.After preliminary screening and rescreening from the rumen contents, three strains of cellulose named N1, protease named N7 and amylase named N9 were obtained, then carries on the fermentation medium optimization on each of them. Through single factor and orthogonal experiment, investigate the effect of culture temperature, culture initial p H, carbon, nitrogen, inorganic salts on cellulase, protease and amylase activity.Through preliminary screening we get the strain N1, witch cellulase enzyme activity is 62.42 U/m L, the strain N7, witch protease activity is 52.35 U/m L, and the strain N9, witch amylase activity is 49.76 U/m L. After fermentation medium optimization, the optimum conditions for cellulase production of N1 is: sodium carboxymethyl cellulose 10 g/L, protein 4 g/L, ammonium sulfate 2 g/L, sulfuric acid, potassium dihydrogen 1 g/L, p H 6, training time is 36 h, temperature 37℃, anaerobic fermentation and cellulase activity increased to 2.46 times, become 153.623 U/m L. The optimum conditions for protease production of N7 is: peptone 10 g/L, sucrose 10 g/L, magnesium sulfate 1 g/L, p H 6, incubation time 36 h, temperature 37 ℃, anaerobic fermentation and protease activity increased to 2.50 times, become 131.136 U/m L. The optimum conditions for amylase production of N7 is: soluble starch 10 g/L, peptone 10 g/L, sodium chloride 3 g/L, p H 6.5, incubation time 36 h, temperature 37 ℃, anaerobic fermentation and anzyme activity increased to 1.45 times, become 72.538 U/m L.