Based on a novel bio-degumming system, the effect of chitosan on the degumming effect of ramie was investigated. The degumming effect indexes before and after the addition of chitosan were assessed, and the enzyme activities (pectinase, xylanase, ligninase and cellulase) were detected. Meanwhile changes in microbial community structure were evaluated. Furthermore, the electron-donating effect of chitosan and cellulose was further simulated by Fukui function. Degumming effect indexes showed the addition of chitosan could effectively increase the breaking strength of degummed ramie (from 6.04 to 6.59 cN/dtex), reduce the fineness (from 10.06 to 8.039 dtex), so that more gums were removed (the residual gum ratio reduced from 16.55 % to 12.09 %) and more cellulose was retained in the degummed ramie (cellulose content increased from 78.01 % to 80.96 %). Enzyme activity measurements revealed that the addition of chitosan increased the activity of degumming enzymes (pectinase, xylanase and ligninase), while decreased cellulase activity. The addition of chitosan induced changes of the community structure, with an increase of degumming microorganisms and a decrease of cellulose-degrading microorganisms. According to Fukui function, chitosan has a stronger electron donating ability than cellulose, which might be one important reason for the changes in enzyme activities and community structures.

中文翻译：

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壳聚糖对苎麻厌氧连续流脱胶的有效增强及其微生物机制


基于一种新型的生物脱胶系统，研究了壳聚糖对苎麻脱胶效果的影响。评估壳聚糖添加前后的脱胶效果指标，检测酶活性 （果胶酶、木聚糖酶、木质素酶和纤维素酶）。同时评估微生物群落结构的变化。此外，通过 Fukui 函数进一步模拟了壳聚糖和纤维素的供电子效应。脱胶效果指标显示，壳聚糖的添加可有效提高脱胶苎麻的断裂强度（从 6.04 cN/dtex 提高到 6.59 cN/dtex），降低细度（从 10.06 dtex 降低到 8.039 dtex），从而去除更多的胶质（残胶比例从 16.55 % 降低到 12.09 %），脱胶苎麻中保留更多的纤维素（纤维素含量从 78.01 % 增加到 80.96 %）。酶活性测量表明，壳聚糖的添加增加了脱胶酶（果胶酶、木聚糖酶和木质素酶）的活性，而降低了纤维素酶的活性。壳聚糖的添加诱导了群落结构的变化，脱胶微生物的增加和纤维素降解微生物的减少。根据 Fukui 函数，壳聚糖比纤维素具有更强的电子供体能力，这可能是酶活性和群落结构发生变化的重要原因之一。