桉木硫酸盐浆木聚糖酶漂白适性及纤维素酶对漂白浆质量的影响

Xylanase Pretreatment in Eucalyptus KP Bleaching

用黑曲霉（Aspengillusniger，An76）产生的合少量纤维素酶的木聚糖酶及H2O2和EDTA等对不同卡伯值的桉木硫酸盐浆进行漂白，同时利用层析分离获得An76酶中无纤维素酶杂质的木聚糖酶活性组分CFX进行对比实验，结果表明酶漂适性随未漂浆卡伯值降低而提高，纤维素酶的存在是造成木聚糖酶漂白中漂白浆粘度下降的根本原因，其活性与漂后废液中葡萄糖与木糖糖基比值变化具有正相关性。

Eucalyptus KP of three different kappa No. levels were pretreated with xylanase isolated fromAspergillus niger strain An76, hydrogen peroxide and EDTA were added to the xylanase for the pre-bleaching. Some of the crude xylanase (X) contaminated by cellulase was purified to give cellulase free xylanase(CFX). Both cellulase contaminated xylanase (X) and cellulase free xylanaes (CFX) were experimented forthe pre-bleaching of eucalyptus KP. Results obtained indicated that crude xylanase (X) gave better bleachingeffects with pulps of a lower kappa number level. The presence of small quantities of cellulase in the crudexylanase tended to give a pulp with lower viscosity. It is interesting to note that the activity of the cellulasecontaminated xylanase exhibited a direct proportionality with the percentage of glucose in the treatment effluent.