复合发酵对棉籽饼混合底物中FG和BG含量的影响

Effect of mixed culture fermentation on the contents of free and bound gossypols in cottonseed cake

试验通过测定棉籽饼混合底物在微生物固体发酵过程中棉酚含量的变化,以研究复合发酵对棉籽饼混合底物中棉酚含量的影响。试验采用添加不同比例的ZD-3与ZD-5和ZD-3与ZD-8对棉籽饼混合底物进行二元复合发酵,然后测定发酵产物中TG、FG、BG含量。试验结果表明:棉籽饼混合底物经复合发酵处理后,均可极显著降低发酵底物中TGF、G和BG含量(P<0.01),并且FG和BG的减少部分均被降解消除;同时发现,ZD-3与ZD-5的复合发酵效果优于ZD-3与ZD-8的发酵效果,并且菌种比例对发酵结果有显著影响。当ZD-3与ZD-5的比例为3:1时,脱毒效果最好,脱毒率可达90.82%。

The aim of this paper was to research the effect of mixed culture fermentation on the contents of free and bound gossypols in cottonseed cake（CSC）.CSC mixed substrates were fermented by mixed culture of different proportion of C.tropicalis ZD-3 with S.cerevisiae ZD-5,or C.tropicalis ZD-3 with A.niger ZD-8,and then through determining the contents of total gossypol（TG）,free gossypol（FG） and bound gossypol（BG） in fermented products to explore the detoxification mechanism of microbial fermentation of CSC.The result showed that the contents of TG,FG and BG in the substrates were all extremely reduced（P0.01）,and the BG and FG of reduction parts were all decomposed.Between two kinds of mixed culture,the fermentation efficiency of C.tropicalis ZD-3 with S.cerevisiae ZD-5 was superior to that of C.tropicalis ZD-3 with A.niger ZD-8.Effect of the proportion between yeasts inocula on fermentation efficiency was significant（P〈0.01）,and when the ratio of C.tropicalis ZD-3 with S.cerevisiae ZD-5 was 3 to 1,the detoxification efficiency was the best,reaching up to 90.82%.