高效木质纤维素分解菌群筛选及其酸碱调节能力研究

Characteristics and selection of efficient lignocellulose degradation microbial community

为获得能够改良土壤酸碱性的微生物群体,以混合堆放牛粪、鸡粪的储粪池外围土样为材料,采用限制培养技术筛选了一组木质纤维素分解菌群,并对该菌群在不同初始pH下的适应能力和纤维材料的分解能力及其耐盐特性进行了研究。结果表明：以不同碳源（滤纸、玉米秸秆、稻草秸秆和小麦秸秆）制作不同初始pH（5.0~11.0）的培养基,接种木质纤维素分解菌群后培养基pH均迅速向中性变化,第3 d集中至8.0左右,6 d后稳定至7.8~8.6;7 d内滤纸、玉米秸秆、稻草秸秆和小麦秸秆失重率分别超过93.15%、50.53%、44.29%和42.60%;以滤纸为惟一碳源、NaCl浓度2.0%的培养基接种,7 d滤纸失重率达84.82%。木质纤维素分解菌群具有较强的适应及调节pH能力,且能够高效分解木质纤维材料,并具有一定的耐盐特性,可见该菌群在酸碱土壤酸碱性改良领域具有一定开发潜力。

oil acidification or alkalization has been a serious global environmental problem.It has not only caused huge losses of agricultural production,but also has been a seriously threat to ecological environment.Therefore,a simple and effective soil improvement method was critical for environmental protection and agricultural production.A group of lignocellulose microbial community was selected from soil samples of cattle and chicken feces compost.The selection was based on restrictive training in an effort to get a group of microbial population with the potential to improve soil acidity and alkalinity.The ability of the microbial system adapting to different initial pH,fiber degradation and salt-tolerance was investigated as well.The results suggested that the pH of culture medium（utilized filter paper,corn straw,rice straw and wheat straw as carbon limiting source） changed sharply and tended towards neutrality when inoculated in a wide pH range（pH of 5.0~11.0） within 6 days.The rates of weight loss of filter paper,corn straw,rice straw and wheat straw respectively exceeded 93.15%,50.53%,44.29% and 42.60% within 7 days of cultivation.When filter paper was used as the sole carbon source at 2.0% salt stress,the rate of weight loss was 84.82% after 7 days of cultivation.This suggested that lignocellulose degradation microbial community had the capability to adapt and regulate pH and effectively degrade lignocellulose materials under culture conditions.Additionally,the microbial community had certain degree of salt resistance.Therefore lignocellulose microbial community had the potential to improve soil acidity and alkalinity.