School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, China.
Jiangsu Heavy Responsibility Group, Pizhou 221300, China.
Carbohydr Polym. 2014 Nov 4;112:615-21. doi: 10.1016/j.carbpol.2014.05.076. Epub 2014 Jun 4.
The crude exopolysaccharides (EPSs) were obtained from Arthrobacter ps-5 fermentation using various carbohydrate sources followed by centrifugation, ethanol precipitation, and the isolated EPSs were further deproteinized and lyophilized. Carbohydrates from various sources resulted in different yield of EPSs from the fermentation and different molecular weight of EPSs. A maximum yield of 0.27 mg/g was achieved by using the culture medium supplemented with sucrose. The EPS produced by glucose-supplemented medium had the maximum content of acidic polysaccharides, subsequently presented the highest biosorption capacity for Cu(2+) and Pb(2+) at 257.9 mg/g and 331.8 mg/g, respectively. The ratio of acidic to neutral polysaccharides presented in EPSs was a key factor to explicate the biosorption mechanism, the higher the ratio, the stronger the biosorption capacity.
粗制胞外多糖（EPS）是从 Arthrobacter ps-5 发酵中获得的，使用了各种碳水化合物源，然后进行离心、乙醇沉淀，分离得到的 EPS 进一步进行脱蛋白和冻干。不同来源的碳水化合物导致发酵过程中 EPS 的产量不同，EPS 的分子量也不同。在添加蔗糖的培养基中，最大产量达到 0.27mg/g。在葡萄糖补充培养基中生产的 EPS 具有最大的酸性多糖含量，随后对 Cu(2+)和 Pb(2+)的生物吸附能力最高，分别为 257.9mg/g 和 331.8mg/g。EPS 中酸性多糖与中性多糖的比例是解释生物吸附机制的关键因素，比例越高，生物吸附能力越强。
