促进草酸青霉降解秸秆的表面活性剂效果研究

为了提高秸秆降解效率,本文探究了不同种类表面活性剂对秸秆降解菌降解秸秆的作用,并筛选出效果最佳的表面活性剂。首先筛选获得一株降解玉米秸秆能力较强的菌株——草酸青霉Z7-6;其次在液体发酵条件下,考察4种表面活性剂(两个浓度)对草酸青霉Z7-6降解玉米秸秆效果及产纤维素类酶的影响;最终通过固体发酵验证表面活性剂的效果。结果表明:筛选出的草酸青霉Z7-6对玉米秸秆具有较好的降解效果,相对降解率达40.58%。液体发酵条件下,0.1%表面活性剂处理下秸秆相对降解率较高,0.1% Triton X-100(TR)和0.1% Tween 80(TW)均可提升草酸青霉Z7-6降解玉米秸秆的效果,两者间无显著差异。0.1% TR处理中滤纸酶活性和羧甲基纤维素酶活性均显著高于其他处理。固体发酵条件下,0.1% TR的提升效果最佳。综合秸秆降解的效果和产酶情况,发现0.1% TR促进草酸青霉Z7-6降解秸秆的效果最好,也可提升该菌株纤维素类酶的活性。

Effects of surfactants on promotion of straw degradation by Penicillium oxalicum

In order to improve degradation efficiency, effects of different types of surfactants on straw degradation by straw-degrading bacteria were explored and the best surfactant were screened out. We first isolated a strain, Penicillium oxalicum Z7-6, with strong ability of degrade corn straw. Under liquid fermentation, effects of four surfactants (with two concentrations) on the degradation of corn straw by P. oxalicum Z7-6 and the production of cellulosic enzymes were investigated. Finally, the effects of the surfactants were verified by solid fermentation. The isolated P. oxalicum Z7-6 could degrade corn straw with high efficiency at a relative degradation rate of 40.58%. Under liquid fermentation condition, the relative degradation rate of straw was higher after treated with surfactants at a concentration of 0.1%. Both 0.1% Triton X-100 (TR) and 0.1% Tween 80 (TW) could significantly promote degradation of corn straw by P. oxalicum Z7-6, and there was no significant differences between the effects of these two treatments. Activities of filter paper enzyme and carboxymethyl cellulase were significantly higher under 0.1% TR compared with other treatments. Under solid fermentation, straw degradation was significantly higher under 0.1% TR compared with other treatments. Thus, the results for straw degradation and enzyme activities show that 0.1% TR has the strongest promotion effect on the degradation of straw by P. oxalicum Z7-6 and cellulosic enzyme activities.