Polak-Berecka Magdalena, Szwajgier Dominik, Waśko Adam
Dept. of Biotechnology, Human Nutrition and Science of Food Commodities, Univ. of Life Sciences in Lublin, Skromna 8, 20-704, Lublin, Poland.
J Food Sci. 2014 Nov;79(11):T2404-8. doi: 10.1111/1750-3841.12674. Epub 2014 Oct 11.
The aim of this study was to assess the removal of Cd(2+) and Al(3+) from aqueous solutions by an exopolysaccharide (EPS) from Lactobacillus rhamnosus E/N. The biosorption kinetics of EPS for Cd(2+) and Al(3+) were studied by equilibrium dialysis after incubation from 0 h to 58 h. The actual concentrations of Cd(2+) and Al(3+) in external solutions were measured by a fluorescence method after complexation with 8-hydroxyquinoline. Binding of metal ions by EPS was observed, with maximum adsorption after 0 to 24 and 48 to 58 h for Cd(2+) , and after 24 h for Al(3+) . The existing analytical method, involving the binding of metal ions was measured using a dialysis membrane was significantly improved in our study. This new method could be applied in future studies of this type. The results of this study demonstrate that EPS from Lb. rhamnosus E/N has a Cd(2+) and Al(3+) biosorption capacity. Surface adsorption of the metal ions at surface of EPS was confirmed through scanning electron microscopy. Fourier transform-infrared spectroscopy analysis suggests a role of the functional groups ─OH, C═O, and COO(-) from EPS in the binding of Cd(2+) and Al(3+) ions.
本研究的目的是评估鼠李糖乳杆菌E/N产生的胞外多糖（EPS）对水溶液中Cd(2+)和Al(3+)的去除效果。通过平衡透析法研究了EPS对Cd(2+)和Al(3+)的生物吸附动力学，孵育时间为0小时至58小时。与8-羟基喹啉络合后，采用荧光法测定外部溶液中Cd(2+)和Al(3+)的实际浓度。观察到EPS对金属离子的结合，Cd(2+)在0至24小时和48至58小时后达到最大吸附，Al(3+)在24小时后达到最大吸附。在我们的研究中，涉及使用透析膜测量金属离子结合的现有分析方法得到了显著改进。这种新方法可应用于未来此类研究。本研究结果表明，鼠李糖乳杆菌E/N产生的EPS具有Cd(2+)和Al(3+)生物吸附能力。通过扫描电子显微镜证实了金属离子在EPS表面的吸附。傅里叶变换红外光谱分析表明，EPS中的─OH、C═O和COO(-)官能团在Cd(2+)和Al(3+)离子的结合中发挥了作用。
