大孔树脂吸附桦褐孔菌多糖色素的机理及工艺优化

Adsorption Mechanism and Process Optimization of Inonotus obliquus Polysaccharide Pigment by Macroporous Resin

为探究大孔树脂吸附桦褐孔菌多糖色素动力学与热力学特征及最佳工艺条件,本实验通过水提醇沉、Sevag法除蛋白、透析制备桦褐孔菌多糖,采用静态吸附实验筛选色素吸附率及多糖保留率评分最高的大孔树脂,研究其吸附动力学与热力学特性,并优化该大孔树脂在动态吸附桦褐孔菌多糖色素中的径高比、吸附时间、上样量以及洗脱流速,确定最佳工艺条件。结果表明,实验筛选的17个不同型号大孔树脂中,大孔树脂HPD-500最为适宜,其吸附色素的过程符合准二级动力学模型,反应过程中受颗粒内扩散与液膜扩散的影响;并且吸附过程符合热力学Freundlich模型,为多分子层吸附,其中吸附焓变>0为吸热反应,吉布斯自由能<0为自发反应,吸附熵变>0为熵增反应。HPD-500吸附色素的最佳条件为径高比1:10,吸附时间1 h,上样量10 mg,洗脱流速1.5 mL/min。在此条件下,桦褐孔菌的色素吸附率为83.15%,多糖保留率为78.89%,多糖纯度由20.40%提升至56.52%。HPD-500大孔树脂具有吸附桦褐孔菌多糖中色素、提高多糖纯度的能力,本文为桦褐孔菌资源高效利用提供了理论及实验基础。

To explore the kinetic,thermodynamic characteristics and optimal conditions of the removal the inner pigment of the Inonotus obliquus polysaccharide by macroporous resin.In this study,the total Inonotus obliquus polysaccharide was prepared by water extraction and alcohol precipitation,Sevag method for protein removal,and dialysis.A preliminary screening of 17 macroporous resins were carried out by static adsorption method.And the score was calculated by pigment removal rate and polysaccharide retention rate.The parameters affecting the pigment inner Inonotus obliquus polysaccharide removal process,such as flow rate,adsorption time,ratio of diameter to height and sample concentration were studied and optimized along with evaluation of kinetic and thermodynamic parameters.The results showed that HPD-500 was the best suitable one among the 17 kinds of macroporous resins.The adsorption process followed pseudo-second-order model,which was affected by both intra particle diffusion and liquid film diffusion.The thermodynamic results showed that the adsorption was more in line with the Freundlich model,which was a multi-molecular layer adsorption.The rmodynamic parameters were also evaluated,enthalpy>0,Gibbs free energy<0,entropy>0,which showed that extraction was an endothermic,spontaneous and entropy increase reaction.Under the optimal conditions for removed pigment with elution ratio of diameter to height of 1:10,adsorption time of 1h,sample weight of 10 mg and flow rate of 1.5 mL/min,the pigment removal rate of Inonotus obliquus polysaccharide was 83.15%,the retention rate was 78.89%,with the purity promoted from 20.40%to 56.52%.The HPD-500 macroporous resin had the ability to remove the pigment and improve the purity of Inonotus obliquus polysaccharide.This article provided a theoretical and experimental basis for the efficient utilization of Inonotus obliquus resources.