废啤酒酵母菌对苹果汁中展青霉素的吸附作用

Adsorption of Patulin from Apple Juice by Waste Beer Yeast

以啤酒厂废弃啤酒酵母菌为吸附剂,研究其对苹果汁中展青霉素的吸附效果和机理。结果表明,废啤酒酵母菌表面具有大量吸附展青霉素的基团,吸附时间、温度、p H值和展青霉素初始质量浓度是影响吸附的重要因素,吸附过程在20 h达到平衡,p H值为4.0时,继续增加p H值,吸附率变化不大;随着温度的升高,废啤酒酵母菌对展青霉素的吸附率呈上升趋势;展青霉素的吸附率随着展青霉素初始质量浓度的增加而降低,且达到平衡时间变短。模型分析结果表明,Langmuir等温吸附模型可以有效模拟废啤酒酵母菌对展青霉素的吸附过程,废啤酒酵母菌对展青霉素的最大吸附量在4、25、37℃分别为3.70、5.05、5.99μg/g。废啤酒酵母菌对展青霉素的吸附过程符合一级动力学模型,属于自发的吸热过程。

Adsorption of patulin from apple juice by using waste beer yeast was investigated in this work. The results showed that a large number of function groups able to adsorb patulin existed on the surface of waste beer yeast cells. Temperature, incubation time, p H and initial patulin concentration were important parameters affecting adsorption efficiency. The adsorption reached equilibrium after 2 h. With increasing p H, the adsorption ratio reached a plateau at p H 4.0. Patulin adsorption ratio increased with increasing temperature, and decreased with increasing initial concentration of patulin, shortening the equilibration time. The adsorption equilibrium could be described by the Langmuir model. The maximum uptake capacities（qmax） obtained by the Langmuir model were 3.70, 5.05 and 5.99 μg/g at 4, 25 and 37 ℃, respectively. The adsorption kinetics of patulin by waste beer yeast was best described using a first-order kinetic model. The adsorption process was spontaneous and endothermic in nature.