绿色糖单孢菌木聚糖酶Svixyn10A基因在不同菌株表达分泌的木聚糖酶对纸浆预漂白效果

Effects of Xylanase Expressed and Secreted by Green Sugar Spore Bacteria Xylanase Svixyn10A Gene in Different Strains on Pre-Treating of Pulp

生物酶制取成本过高是影响纸浆生物漂白推广商用的首要因素,如何降低产酶成本就成为生物漂白研究要考虑的首要问题。采用绿色糖单孢菌木聚糖酶基因在大肠杆菌、毕赤酵母菌中表达分泌的木聚糖酶处理桉木硫酸盐浆,考察其预漂白效果,并与酵母菌表达的胞外酶、商用木聚糖酶的效果进行对照。结果表明:毕赤酵母菌表达的木聚糖酶对纸浆的预处理效果良好;当预处理酶用量20 IU·g-1浆,处理时间60 min,后续DED三段漂白总用氯量2.4%时,可使桉木硫酸盐浆白度达到89%ISO;与商品木聚糖酶相比,漂后纸浆黏度损失较少,白度稳定性更好。

The high cost of enzyme preparation is the primary factor affecting the promotion of commercial pulp bio-bleaching, therefore, how to reduce the cost of producing the enzyme has become the most important issue to consider in biobleaching study. In this study, the xylanase which were expressesd and secreted by green sugar spore bacteria xylanase gene in E. coliand Summarized yeastwere used to treat eucalyptus Sulfatepulp to examine its pre-bleaching effect. At the same time, this research effction was controlled with the effection of extracellular enzymes and commodity xylanase expressed by yeast. The results showed that： xylanase expressed by Summarized yeasthad good pretreatment effect on pulp; When the pre-processing enzyme dosage was 20 IU·g^-1 pulp, processing time was 60min, total amount of chlorine was 2.4% during the follow-up DED three sections bleaching, eucalyptus Sulfatepulp brightness could reach 89%ISO; compared to the commodity xylanase, after the bleaching, not only could the viscosity of the pulp loss less but also brightness stability was better.