娄彻氏链霉菌发酵改善水稻秸秆加工性能的研究

【目的】应用正交试验,研究了娄彻氏链霉菌发酵对水稻秸秆加工性能的影响。【方法】在30℃、含水率为65%的条件下,探究了发酵时间、接种量、碳氮比3因素对水稻秸秆质量损失率,纤维素、半纤维素和木质素的降解率,以及最大压应力和黏度(加工性能)的影响,并利用SPSS 19.0软件分析了降解条件与水稻秸秆理化性能的相关性。【结果】娄彻氏链霉菌发酵条件对水稻秸秆的降解性与加工性能的影响顺序为:发酵时间碳氮比接种量;通过相关性分析可得,发酵时间与纤维素、半纤维素和木质素的降解率以及质量损失率极显著正相关,与秸秆的最大压应力和黏度显著负相关。发酵的最优条件为:碳氮比为25,接种量为0.8%,发酵时间为20 d。此时水稻秸秆的最大压应力为5.62 MPa,较原秸秆降低了10.74%;黏度为415.8 m Pa"s,较原秸秆提高了29.7%;平衡扭矩则降低了18.2%。微观结构(SEM)显示发酵后水稻秸秆表面粗糙、凹凸不平,内部结构发生了变化。【结论】娄彻氏链霉菌发酵改变了水稻秸秆的物理化学结构,改善了水稻秸秆的加工性能。

Improving processability of rice straw by fermentation using Streptomyces rochei

Objective] An orthogonal experiment was conducted to explore the impact of Streptomyces rochei on the pro?cessing performance of rice straw. Method] The effects of three factors ( fermentation time, inoculum amount and the ratio of carbon to nitrogen) on the degradation and processing performance of rice straw were analyzed under fermentation conditions of 30 °C and 65% moisture content. The degradation rates of cellulose, hemicellulose, lignin, maximum com?pressive stress and viscosity were investigated, and the relationship between the degradation conditions and the physical and chemical properties of rice straw were analyzed by SPSS 19.0 software. Result] The influence of factors on mass loss rate, degradation rates of cellulose, hemicellulose, lignin, the maximum compressive stress and viscosity of rice straw was found in the order of fermentation time>carbon and nitrogen ratio>inoculation amount. The correlation analy?sis showed that fermentation time had a significantly positive correlation with the degradation rate of cellulose, hemicellu?lose and lignin, and the mass loss rate was negatively correlated with the maximum compressive stress and viscosity of rice straw. The optimal conditions for Streptomyces rochei fermentation of rice straw were:fermentation time was 20 days;carbon to nitrogen ratio was 25;inoculation amount was 0.8%. The physical and chemical properties of the rice straw un?der the optimal fermentation conditions were: maximum compressive stress 5. 62 MPa, which was 10. 74% lower than that of the untreated materials;viscosity 415.8 mPa .s, which represented an increase of 29.7% from the untreated rice straw;and the balance of torque decreased 18.2%. Scanning electron microscopy showed that after fermentation, the sur?face of rice straw was more rough and uneven, and the internal structure of rice straw had changed. Conclusion]The physical and chemical structure of rice straw was improved by Streptomyces rochei fermentation, consequently, the pro?cessing performance of rice straw would be enhanced.