多菌种混合固态发酵秸秆的研究

Study on the solid state fermentation of straw with multiple strains

实验以绿色木霉(Trichoderma viride)、黑曲霉(Aspergillus niger)、产朊假丝酵母(Candida utilis)、青霉(Penicillium)、长枝木霉(Longibrach iatum Rifai)为菌种,在已有单因素实验的基础上选取影响较明显的4个因素(发酵温度、时间、混菌接种量和酵母接入时间)进行固态发酵正交优化实验(其中混菌组合比例均为1∶1∶1),通过测定纤维素酶活、粗纤维素降解率来确定最佳发酵条件。结果表明:以纤维素酶活为指标,酶活最高的是绿色木霉、黑曲霉和假丝酵母三种菌种的组合,其混菌接种量为5%,发酵时间为3 d,酵母与混菌同时接入,发酵温度为30℃,纤维素酶活达到85.73 U/m L;以粗纤维素降解率为指标,降解率最高的是长枝木霉、青霉和假丝酵母三种菌种的组合,其混菌接种量为10%,酵母第1 d接入,30℃发酵4 d,纤维素降解率达到38.89%。农作物经混菌固态发酵后,营养价值得到提高,可作为一种优质饲料来饲喂家畜,这对于充分利用可再生资源,改善农村环境污染有着积极作用。

In this study, Trichoderma viride ,Aspergillus niger, Candida utilis ,Penicillium and Longibrach iatum Rifai were used as fungi, 4 factors （ fermentation temperature, time, inoculation amount of mixed bacteria and the time of yeast access ） were selected on the basis of single factor experiment.The orthogonal experiments of solid state fermentation were carried out （the ratio of mixed bacteria was 1：1 ： 1 ） ,the optimum fermentation conditions were determined by measuring the cellulase activity and the degradation rate of crude cellulose.The results showed that with cellulase activity as the index, the highest activity of the enzyme was the combination of Trichoderma viride, Aspergillus niger and Candida utilis, the inoculation amount of mixed bacteria was 5% ,fermentation time was 3 days, yeast and mixed bacteria were accessed at the same time, the fermentation temperature was 30 ℃ and the cellulase activity was 85.73 U/mL.Based on the degradation rate of crude cellulose,the highest degradation rate was the combination of Longibrach iatum Rifhi, Penicillium and Candida utilis, the inoculation amount of mixed bacteria was 10% ,and the degradation rate of cellulose reached 38.89% when the yeast was inoculated on the first day and fermented at 30 ℃ for 4 days.After the solid-state fermentation of mixed bacteria, the nutritional value of crops were improved and can be used as a high-quality feed to feed livestock.This will play a positive role in making full use of renewable resources and improving rural euviromnental pollution.