The Screening Of Strain For Bamboo Shoot Processing Waste Fermentation And Optimization Of Fermentation Conditions

A great deal of bamboo shoots were obtained in spring season every year in China.It leadto form lots of waste of bamboo shoots processing, such as shoot head and bamboo shootshell. These waste are rich in crude fiber, crude protein and trace element. It is necessary toutilize the useful contents in order to improve the environmental pollution if they are directlyentered into surrounding. In this paper, efficient strains of high cellulase activity will bescreened to develop the feed production using the bamboo shoots waste as material, by usingthe CMC-Na medium and enzyme activity analyses under flask culture condition. Thebiological characters of these strains will be further studied. Then, the mixed culture wereconducted with three kinds of strains, such as proteinase activity strain, lactic acid bacteriaand yeast, and are further optimized of proportion among three strains. The effects of carbonsource, nitrogen source,water content and initial pH and temperature on solid statefermentation were investigated, then the conditions of solid-state fermentation were thenoptimized. The results were as follow.The results showed that13sprains of cellulase activity were obtained, by isolation ofCMC-Na medium, and3strains were higher enzyme activity among them by comparing thesize of transparent circle in plate.The two strains have the higher cellulase activity under theflasked culture, named as N2and N8, respectively. The yields of enzyme formation reached0.1918U/mL and0.1742U/mL, respectively. The optimized conditions are that the culturephase is3to30h, pH is7, at37℃for strain of N2, and3to30h, pH6.5, at37for strain ofN8.The strong anti-caking effetc among5sprains were not detected. The proportion of eachstrain N2, N8and BX2is3:2:1, the inoculum size is10%. The inoculum size of2%yeast H7and lactic acid bacteria G16, respectively, were inoculated after24h fermentation andcontinued to culture for2days. The yields of CMC enzyme activity reached30.2U/mL,and the crude protein in bamboo shoot shell was24.36%under this optimization condition.By taking advantage of strains which selected from the earlier experiment, the finalconclusion can be obtained that the best ingredients of fermentation substrate should contain86%bamboo shell powder,10%bran and4%(NH4)2SO4. Added water according to solid- liquid ratio1:1.5, reset pH to6,and fermented at37℃for3hours,the experimental resultshowed that CMC enzyme activity reached to65.02U/mL,and crude protein in bamboo shellreached to25.78%.