Optimization of culture medium composed of rice by-products for carotenoid production by fermentation of Neurospora crassa

The culture medium composed of rice by-products (rice chaff and defatted rice bran) for carotenoid production by Neurospora crassa was optimized through statistical experiment design and data analysis. The defatted rice bran, (NH4) 2SO4, KH2PO4, MgSO4, MnSO4 and CaCl2 were evaluated as factors affecting carotenoid biosynthesis by Neurospora crassa, and the significant factors were screened by a Plackett-Burman design. Then the culture medium was optimized by response surface methodology. Results indicated that defatted rice bran and (NH4) 2SO4 were the significant factors on carotenoid production. The optimal culture medium consisted of 64.58% defatted rice bran, 33.85% rice chaff and 1.57% (NH4) 2SO4 at which the yield of carotenoids was gotten up to 366mg/kg culture using the optimized fermentation parameters.