分批和分批补料培养合成低纤维素酶酶活力的木聚糖酶

PRODUCTION OF CELLULASE-POOR XYLANASE BY BATCH AND FED-BATCH FERMENTATIONS

研究了里氏木霉Rut C 30在分批培养和分批补料培养模式下合成低纤维素酶酶活力的木聚糖酶及其在生物漂白上的应用.底物质量浓度为15g/L的木聚糖分批培养合成木聚糖酶,酶活力为152.09IU/mL、酶产率为2 112.4IU/(L·h)、酶得率为10 139.3IU(以每克木聚糖计,下同).底物质量浓度为17g/L的木聚糖分批补料合成木聚糖酶,酶活力为252.14IU/mL、酶产率为3 501.9IU/(L·h)、酶得率为14 831.8IU,产酶效果远优于分批培养模式.该木聚糖酶用于草浆预漂白,在相同有效氯用量下,与对照浆相比可使白度提高2%～5%,SBD;在达到相同白度条件下,木聚糖酶预处理的纸浆后续漂白有效氯用量可降低43%.

Preparation of cellulase-poor xylanase by Trichoderma reesei Rut C 30 in batch and fed-batch fermentations and its application on biobleaching were investigated. The xylanase activity, xylanase volumetric productivity and xylanase yield in batch fermentation were 152, 09 IU/mL,2 112.4 IU/（ L. h） and 10 139.3 IU/g xylan, respectively, when 15 g/L xylan was employed as carbon source. Compared to batch fermentation, xylanase formation in fedbatch culture,in which 17 g/L xylan was employed as carbon source, was more efficient and the xylanase activity, xylanase volumetric productivity and yield were 252.14 IU/mL,3 501.9 IU/（ L·h） and 14 831.8 IU/g xylan, respectively. When straw pulp was pretreated with the xylanase-poor xylanase followed by a hypochlorite bleaching, a pulp brightness of 2 % - 5 % （SBD） higher than that of the untreated one under the same hypochlorite dosage could be obtained, or 43 % of active chlorine consumption could be saved under the same brightness.