Characterization and chromium biosorption potential of extruded polymeric substances from Synechococcus mundulus induced by acute dose of gamma irradiation.

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-SO3, C-O-C and a newly formed peak at 1593 cm-1 (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 CIDSC (0.722) and CIXRD (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-1 h-1 is the maximum biosorption rate (SBRmax) of Cr(VI) for R-EPS, whereas 0.0204 mg L-1 h-1 SBRmax for the C-EPS respectively.

Radioprotective effect of Date syrup on radiation- induced damage in Rats.

Ionizing radiation has cytotoxic and genotoxic effects caused mainly by the oxidative damage induced by free radical release. The need for radioprotectives is increasing to protect normal tissues during radiotherapy. In the present study, we investigated the radioprotective effect of Date syrup in rats subjected to whole body radiation at 6 Gy through biochemical, molecular and histopathological analysis. Significant elevations were recorded in the activities of serum ALT, AST, ALP and LDH and in the levels of all lipid profiles parameters, while the level of HDL-C was reduced. The concentration of liver MDA was elevated with depletion of hepatic glutathione (GSH) and catalase. DNA damage was evidenced by increased DNA strand breakage and DNA-protein crosslinks. Significant elevations were observed in the expression of liver TNF-α and serum activity of matrix metalloproteinase (MMP-9). Pretreatment of rats with Date syrup ameliorated the tissue damage induced by radiation as evidenced by the improvement of liver function, antioxidant status and reduction of DNA damage. Besides, liver TNF-α expression and serum MMP-9 activity were reduced. In conclusion, Date syrup could alleviate the toxic effects of ionizing radiation and thus is useful as a radioprotective in radiotherapy regimen.