Investigation of α-amylase production by bacillus amyloliquefaciens using solid-substrate fermentation (ssf)

ABSTRACTMSc ThesısINVESTIGATION OF α-AMYLASE PRODUCTION BY BACILLUSAMYLOLIQUEFACIENS USING SOLID-SUBSTRATE FERMENTATION (SSF)Veyis SELENFırat UniversityGraduate School of Natural and Applied SciencesDepartment of Chemical Engineering2006, Page: 72In this study, the effect of medium conditions on production of α-amylase by Bacillusamyloliquefaciens NRRL B-645 and medium of optimum enzyme production in solid substratefermentation were examined. Hazelnut oil cake was used as a solid substrate. Primarily theeffects of organic and inorganic nitrogen sources on production of α-amylase was investigatedand than quantity of carbon source, effects of CaCl2.2H2O, MgSO4.7H2O, KH2PO4, NaCl,EDTA, like inoculum concentration, fermentation temperature, shake speed and initial pHparameters were examined.It was seemed to sources of organic nitrogen in comparison to inorganic nitrogensources had positive effect on production of enzyme. NaNO3, one of inorganic sources,negatively effects on enzyme production and decreases activity. Besides medium components,from physical parameters temperature and shake speed have effect on enzyme activity wasdeduced.Maximum enzyme production was obtained as 4531 IU in fermentation mediumcontaining 25 g/l hazelnut oil cake, 5 g/l peptone, 2.5 g/l yeast extract, 5 g/l (NH4)2SO4 at 33 oCand 150 rpm. There was not significant effect of the other medium components on α-amylaseproduction in solid substrate fermentation. This shows that microorganism in different mediumscompensate needty of these elements from natural substrate and tap water..Keywords: α-Amylase, Microbial enzyme production, B. amyloliquefaciens, Solidsubstrate fermentation. .