通过复合菌系获取胞外木聚糖酶策略及其特性研究

Strategy of Getting Extracellular Xylanase by A Microbial Consortium and Its Characteristics

为了获得高效木质纤维素复合酶,从秸秆堆肥土壤中经过长期定向驯化,筛选到一组可快速分解秸秆且稳定的复合菌系.该复合系菌系对水稻秸秆具有很强的分解能力,并产生乙酸、丙酸、丁酸等挥发性有机物.分解能力测定和DEEG分析结果表明,复合菌系经长期定向驯化,分解功能和微生物组成稳定.该复合菌系在常温液体静止培养条件下高效分泌胞外木聚糖酶,木聚糖酶活最高可达13.2IU/mL.从复合菌系获取的胞外粗酶液对秸秆具有明显水解糖化能力,经48h水解,玉米秸秆芯和水稻秸秆分别减重21.1%和11.9%,还原糖含量分别为2.4g/L和1.3g/L.

To obtain efficient lignocellulolytic complex enzymes, a stable and efficient microbial consortium with the ability to degrade rice straw was screened from composted agricultural wastes with directed acclimation. The screening process, degradation ability, characteristics of enzymes, and functional and microbial stabilities of the microbial consortium were discussed. The results indicated that the microbial consortium degraded rice straw effectively, and produced volatile products which would be further used. DGGE analysis and determination of degradation ability of different generations indicated that the microbial consortium was structurally and functionally stable. The microbial consortium produced extraceUular xylanase effectively at 35℃ ,and the maximum xylanase activity was 13.2IU/ml of fermentation broth during the rice straw degradation. The crude extracellular enzymes of the microbial consortium could degrade natural rice straw and corn stalk notablely.