MB22木聚糖酶发酵条件的研究
2007-04-13 11:56:50   来源：本站原创   评论：0 点击：

Study on Fermentation Conditions of Xylanase by MB22
Peng Xinbang,Ma Geli,Li Guoyi,Chen Chuntao
Abstract The optimal medium and fermentation conditions of xylanase by MB22 were studied using single -factor-turn and orthogonal experiment. The results showed that the medium was composed of corncob meal120g/l，wheat bran280g/l，(NH4)2SO44g/l，CaCO31.5g/l，Tween80 2.0g/l，MgSO4·7H2O，1.5g/l，using corncob meal and wheat bran as carbon source.The optimum conditions were initial pH5.0，the temperature of the shaking table 30℃,rotating speed 160r/min, incubate time for 84h.Under these optimal conditions，the highest xylanase activity of 898.23U/ml of MB22 was obtained. Although this data needs to be increased compared with some higher yield strains,this result provided theoretical basis for further studies in producing xylanase by micro-organism.
Key words xylan；xylanase；fermentation condition；orthogonal experiment

    木聚糖酶(EC3.2.1.8)是一类以内切方式降解木聚糖分子中β-1,4木糖苷键的酶类,其主要水解产物为木二糖和木二糖以上的低木聚糖,还有少量木糖和阿拉伯糖[1]。在食品工业中，可利用木聚糖酶降解半纤维素的主要组分木聚糖来生产功能性低聚木糖等高附加值产品[2]。在造纸工业中，木聚糖酶可用于纸浆在氯气、二氧化氯、过氧化氢、氧、臭氧等化学药品漂白前预处理。木聚糖酶漂白技术易与传统的纸浆漂白工艺相容,酶处理后可减少化学漂剂的用量,而纸浆强度等物理性质不会发生改变[3]。将碱性木聚糖酶用于麦草浆的漂白，不仅可以降低化学漂白试剂的成本，而且可以提高麦草浆质量，并减轻了废水处理的负担[4]。另外,木聚糖酶作为饲料添加剂,可提高饲料的能量值和饲料利用率[5]。
    本研究以富含半纤维素的廉价基质玉米芯粉和麸皮为营养碳源，对自筛细菌菌株MB22产木聚糖酶的培养基配方和发酵条件进行因素轮换法试验和正交设计试验，并对多个因素进行优化处理，以确定最佳培养基和发酵时间，为木聚糖酶制剂的进一步研制提供理论依据。