Department of Botany, Faculty of Science, Mansoura University, Mansoura, Egypt.
Department of Biology, Faculty of Sciences and Arts Khulais, University of Jeddah, Jeddah, Saudi Arabia.
Environ Sci Pollut Res Int. 2019 Nov;26(31):31998-32012. doi: 10.1007/s11356-019-06202-x. Epub 2019 Sep 6.
This study characterized the extruded polymeric substances (EPS) secreted from Synechococcus mundulus cultures under the effect of 2-KGy gamma irradiation dose. The EPS demonstrated seven monosaccharides, two uronic acids and several chemical functional groups: O-H, N-H, =C-H, C=C, C=O, COO-, O-SO, C-O-C and a newly formed peak at 1593 cm (secondary imide). The roughness of EPS was 96.71 nm and only 28.4% total loss in weight was observed at 800 °C with a high degree of crystallinity quantified as CI (0.722) and CI (0.718). Preliminary comparative analyses of EPS exhibited high protein content in the radiologically modified (R-EPS) than control (C-EPS). Modified EPS were characterized with a high biosorption efficiency, which could be attributed to its high content of uronic acids, protein and sulphates as well as various saccharide monomers. Data revealed that 0.0213 mg L h is the maximum biosorption rate (SBR) of Cr(VI) for R-EPS, whereas 0.0204 mg L h SBR for the C-EPS respectively.
本研究描述了在 2-KGy 伽马辐射剂量作用下聚集体(EPS)从聚集体(Synechococcus mundulus)培养物中分泌的情况。 EPS 表现出七种单糖、两种糖醛酸和几个化学官能团:O-H、N-H、=C-H、C=C、C=O、COO-、O-SO、C-O-C 和一个在 1593 cm 处新形成的峰(亚酰胺)。EPS 的粗糙度为 96.71nm,在 800°C 时仅观察到 28.4%的总失重,结晶度较高,CI(0.722)和 CI(0.718)分别为 0.722 和 0.718。EPS 的初步比较分析表明,放射性修饰(R-EPS)的蛋白质含量高于对照(C-EPS)。修饰的 EPS 具有较高的生物吸附效率,这可归因于其较高含量的糖醛酸、蛋白质和硫酸盐以及各种单糖。数据显示,R-EPS 的 Cr(VI)最大生物吸附速率(SBR)为 0.0213mg L h,而 C-EPS 的 SBR 为 0.0204mg L h。