米根霉菌纤维素酶活性及其对农田废弃物的降解效果

Cellulose Enzymatic Activity of Rhizopus oryzae and Degrading Efficiency on Agricultural Waste

【目的】对米根霉菌的纤维素降解酶活性及其对农田废弃物降解效果进行探究和测定,以期促进农业废弃资源的合理利用,减少农业废弃物对生态环境的污染。【方法】把从霉烂的玉米棒芯中分离纯化到的米根霉菌C1,通过液态试验。测定发酵过程中羧甲基纤维素酶(CMCase)、滤纸酶(FPase)和微晶纤维素酶(Avicelase)的活性;将菌液接入到菜叶中,测定该菌株的降解力和酶活变化,分析其降解效果。【结果】在发酵液中,米根霉菌的CMCase酶活>Avicelase酶活>FPase酶活,其中CMCase活性达到35.33 U·mL^(-1),具有较强的活性。在固体发酵中,米根霉菌对农田废弃菜叶有很强的降解效果,在第6天时生成大量腐烂液,降解率为47%,而未接菌对照基本无降解,二者有明显差异。【结论】本试验所用的米根霉C1菌株属于纤维降解菌,具有较高的纤维素酶活性,对农田废弃菜叶具有明显的降解效果,可明显缩短降解时间,研究结果可为农田废弃物的降解和利用提供理论基础和指导思路。

【Objective】Activity and efficiency of agriculture waste-degrading capability of Rhizopus oryzae C1 were investigated.【Method】R.oryzae C1 isolated from mold-infected corn cobs was cultured in a liquid medium to measure the activities of carboxymethyl cellulase(CMCase),filter paper enzyme(FPase),and microcrystalline cellulase(Avicelase).Subsequently,the fermentation broth was introduced onto vegetable leaves to estimate the decomposition effect of R.oryzae C1.【Result】The greatest enzymatic activity of CMCase was detected in R.oryzae C1 at 35.33 U·mL^(-1) followed by those of Avicelase and FPase.The isolated R.oryzae C1 displayed a significant degradation effect on the vegetable farm waste.Within 6 d after introduction of the fermentation broth on vegetable leaves,47%of the starting waste material was liquified.In contrast,no decomposition appeared on control.【Conclusion】R.oryzae C1 had shown to be a fiber-degrading fungus with a high CMCase activity and a significant decomposition efficiency on farm discards.The bacterial fermentation broth demonstrated a rapid and high rate in decomposing vegetable leaves.It was conceivably that R.oryzae C1 or its derivatives be developed to degrade field waste materials and vastly curtail pollution and improve ecology of a farming environment.