摘要
以双歧杆菌和鼠李糖乳杆菌为研究对象,研究其对不同浓度铅的耐受性和吸附性,对pH值、初始湿菌量以及初始铅离子浓度进行单因素试验,利用热力学及动力学模型对两株乳酸菌结合铅离子的过程进行模拟。分析结果表明:两株菌对铅的耐受性较好,初始铅离子浓度为50 mg/L,吸附最佳条件是pH值6,初始湿菌添加量1g/L,该条件下双歧杆菌和鼠李糖乳杆菌对铅的吸附率分别为97.44%,96.87%;Langmuir-Freundlich模型比Langmuir模型和Freundlich模型更适合其结合铅离子的过程,准二级动力学模型比准一级动力学模型更适合,说明两株菌与铅的作用机制为化学吸附和物理吸附。
Bifidobacterium and Lactobacillus rhamnosus were studied about their the tolerance and adsorption of lead.The singlefactor experiments were carried out by pH,the initial amount of bacteria and the initial lead concentration.The process of two strains combined with lead ion was simulated by thermodynamics and kinetic models.The state of lead ion was analyzed by scanning electron microscopy（SEM）and energy dispersive spectroscopy.The results showed that two strains had good tolerance to lead.The optimal conditions of adsorption were as follows：pH was 6,initial amount of bacteria was 1 g/L,initial concentration of lead was 50 mg/L,and the adsorption rates of lead were 97.44% and 96.87%,respectively.Langmuir-Freundlich model was more suitable than the Langmuir and Freundlich ones.Pseudo second order model had dominance in comparison to pseudo first order model.It showed that the mechanism of two strains combined with lead was chemical adsorption and physical adsorption.
作者
徐颖
李洁
贺丹丹
吕嘉枥
XU Ying;LI Jie;HE Dan-dan;LU Jia-li(School of Food and Biological Engineering, Shaanxi University of Science Technology, Xi ＇an , Shaanxi 710021, China)
出处
《食品与机械》
CSCD
北大核心
2018年第3期49-53,共5页
Food and Machinery
基金
陕西省教育厅自然基金专项项目(编号:2018JK0121)
陕西科技大学科研启动金-自然科学预研基金(编号:2016BJ-21)
国家级大学生创新创业训练计划项目(编号:201710708045)
关键词
乳酸菌
铅离子
耐受
吸附
动力学
Lactobacillus
Pb^2＋
tolerance
adsorbent
kinetics
