混菌发酵水稻秸秆生产柠檬酸工艺的研究

Study on production technique of citric acid from mixed fermented rice straw

研究了黄孢原毛平革菌、里氏木霉和黑曲霉共同发酵生产柠檬酸。首先以水稻秸秆中木质素、半纤维素和纤维素的降解率为参考指标,通过单因素试验和多因素正交试验考察黄孢原毛平革菌和里氏木霉对水稻秸秆的降解情况,最佳的结果:初始pH为4.0,黄孢原毛平革菌和里氏木霉的比例为1∶5,黄孢原毛平革菌和里氏木霉的复合接种量为18%,最佳的发酵降解时间140h。然后接种黑曲霉,以柠檬酸的产量为参考指标,通过单因素试验和多因素正交试验考察黑曲霉发酵情况,最佳结果:初始pH为4.0,黑曲霉的接种量为15%,最佳的发酵降解时间140h,柠檬酸的产量达到79.83g·L^(-1)。

This experiment studied the citric acid on the Richter scale produced by the fermentation of yellow bacteria spore hairs flat leather,trichoderma reesei and aspergillus Niger. Using rice straw lignin,hemicellulose and cellulose degradation rate as reference indices,through the single factor test and multifactor orthogonal test to investigate the effect of yellow bacteria spore hairs flat leather and trichoderma reesei on rice straw degradation. The optimum results are：initial pH value of 4.0,proportion of yellow spore bacteria hairs fl at leather to trichoderma reeser is 1 ∶ 5, compound inoculum size of yellow spore bacteria hairs fl at leather and trichoderma reesei is 18%,and fermentation degradation time is 140 h. Then inoculated aspergillus Niger,using yield of citric acid as the reference indexe,through the single factor test and multifactor orthogonal experiment to investigate fermentation of aspergillus Niger,the optimum results are：initial pH value is 4.0,inoculum size of aspergillus Niger is 15%,the fermentation degradation time is 140 h,the yield of citric acid reached 79.83g· L（-1）.