| The rapeseed cake is rich in high protein content with great utilization value, but the utilization range is limited for the components of sinigrin, erucic acid, phytic acid, tannin composition and anti-nutrient factors. In the present paper, experiments on rapeseed cake were carried out to study the screening of strains for detoxication and the condition of fermentation. The results were as follows:(1)6 strains of mould,5 strains of yeast and 8 strains of bacteria which all had the ability to detoxicate the glucosinolate, isothiocyanate and oxazolidine thione were isolated from soil and the mouldy rapeseed cake. Three excellent strains, named M2, X3 and X8, were isolated from the fermentation with single strain.(2) Though mixed fermentation with mixture of two or three strains, the results showed that the effect of mixed fermentation was better than single strain fermentation. The mixed fermentation with three strains was better than two strains. When the rapeseed cake was fermented with mixture of three strains M2, X3 and X8, the detoxication rate reached to 67.8%.(3)The effect of temperature, initial pH, sugar addition, inoculation ratio and inoculation volume on mixed fermentation with three strains M2, X3 and X8 was study by orthogonal test. The results showed the optimal detoxication conditions were fermented with inoculation ratio 0.5:0.5:1, addition of 8% sugar and 8% inoculation volume at 30℃and initial pH 6.5, and the detoxication rate reached to 81.24%.(4)The content of crude protein which is the primary nutrient substance was increased in the process of fermentation. The increasing extent of crude protein from the mixed strains fermentation was better than single strain fermentation. The mixed fermentation with three strains was better than two strains. At the best conditions of detoxication, the content of crude protein was increased by 19.7% from the mixed fermentation with mixture of three strains M2, X3 and X8.
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