Technology about preparation for chitosan reserving protein

采用D -近似最优设计法系统地研究了NaOH质量分数、碱处理时间及碱处理温度这三个主要因素对制备壳聚糖的影响 :当碱液质量分数增加时 ,壳聚糖的脱乙酰度增加 ,但其速度却在减小 ,当碱液质量分数达到 40 %时 ,脱乙酰度出现峰值 ,约为 90 % ,而后增加碱液质量分数时 ,脱乙酰度反而下降 ;随着反应温度的升高 ,其脱乙酰度几乎线性递增 ,当温度达到 2 0 0℃附近时 ,曲线趋于平直并且脱乙酰度达到最大 ;随着反应时间的增加 ,脱乙酰度开始呈线性增加 ,当反应时间超过 5 0min后 ,脱乙酰度有下降趋势 ;在一定碱液质量分数 (4 0 % )条件下 ,脱乙酰度随着温度的增加而增加 ,因此 ,若需获得较高质量的壳聚糖 。

The effects of three factors (concentration of NaOH, time of NaOH treatment, and temperature of NaOH treatment) in preparation of chitosan are studied according to D-approximate design experimental method. The degree of deacetylation of chitosan increases with the concentration of NaOH, and the ascend pace of the degree of deacetylation of chitosan diminishes with the increasing concentration of NaOH. When the concentration of NaOH attain 40%, the degree of deacetylation of chitosan shows a peak value, and is 90% or so. The degree of deacetylation of chitosan descends when the concentration of NaOH is increased further. The degree of deacetylation increases with the reaction temperature in linearnrity. The curve goes to flat at 200℃ or so, and the degree of deacetylation of chitosan reaches the maximum. The degree of deacetylation increases with the reaction time in linearity at the beginning, and then it begins to descend when the reaction time exceeds 50 minutes. The degree of deacetylation increase with the reaction temperature at the special concentration of NaOH(40%). So the temperature must be increased if higher quantity of chitosan acquired.