泡沫分离法纯化枸杞多糖及其动力学过程分析（英文）

Purification of Lycium barbarum Polysaccharides by Foam Separation and Kinetic Analysis of the Process

采用泡沫分离法纯化枸杞多糖(Lycium barbarum polysaccharides,LBPs)。通过苯酚-硫酸法测定LBPs含量,以富集比(E)和回收率(R)为响应值,采用响应面法Box-Behnken设计,建立了三因素三水平拟合模型,优化了稀释倍数、初始pH值和气体流速对分离效果的综合影响;在验证得到的最佳工艺条件下,对枸杞多糖泡沫分离的动力学模型进行了分析。稀释倍数7.6、初始pH 3.42、气体流速295 m L/min时,富集比和回收率最高,分别为2.57和57.31%,与验证值(2.41和61.28%)的相对误差分别为6.6%和6.5%;动力学分析显示,泡沫分离枸杞多糖的过程可拟合为一级化学反应,等效速率常数为0.006 02 min-1。实验建立了一种简单、高效的枸杞多糖纯化思路,并对生产工艺过程提供了一定的理论支持。

Foam separation was used for purifying polysaccharides from Lycium barbarum L.(LBPs) in this paper. LBPs were detected by phenol-sulphuric acid method and evaluated by enrichment ratio(E) and recovery(R). The effects of dilution fold, initial pH and gas velocity on separation efficiency were assessed based on a fitting model proposed by response surface methodology with Box-Behnken design. The optimal levels of the three factors were established and validated. A further study was performed to kinetically investigate the purification process. As a result, when dilution fold was 7.6, initial pH 3.42, and gas velocity 295 m L/min, maximum predicted values of E and R(2.57 and 57.31%, respectively) were obtained, indicating a relative error of 6.6% and 6.5% compared with the experimental values(2.41 and 61.28%), respectively. Kinetic experiments showed that the process could be described as a first-order reaction with an equivalent rate constant of 0.006 02 min-1. This study has provided a novel method for purification of LBPs, and the kinetic process may provide valuable guidance for enhancing the purification efficiency.