利用微生物混合培养物生产甜菜渣单细胞蛋白

SINGLE-CELL PROTEIN PRODUCTION FROM SUGAR BEET RESIDUE BY A MICROBIAL MIXED CULTURE

利用半连续培养的方法组建了一个由７种微生物组成的能以甜菜渣作原料生产单细胞蛋白的混合培养物．在最佳条件下，甜菜渣被转化为含粗蛋白为４５％的单细胞蛋白，其氨基酸组成基本符合联合国粮农组织推荐的最佳蛋白质的组成．此种微生物的混合培养物在营养方面是自我满足的，外来的微生物不能作为污染物存在于发酵系统中．因此，发酵过程可以在不灭菌的条件下进行．本研究还对混合培养物中各种微生物在降解甜菜渣过程中的作用进行了初步地探讨．

A stable microbial mixed culture thriving on sugar beet residue was constituted by means of semi-continuous cultivation using sugar beet residue (SBR) as a sole carbonsource.The mixed microbial culture consists of seven micro-organisms. The coculture isself-sufficient in its nutrient demands. No contaminant was found in the unsterilized mediafermented by this coculture. Under the optimal conditions, SBR was rapidly converted intomicrobial biomass with a 50 % biomass yield. The light brown colored single-cell protein(SCP) with fragrant smell contained more than 45 per cent of crude protein on a dry weightbasis. The amino acid profiles in the SCP was similar to the ideal amino acid pattern recommended by the Food and Agriculture Organization of United Nations (FAO). The nutrientrelationship and the functions of the microbes in the coculture in converting SBR into SCPwere also investigated.