کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
2087895 | 1080718 | 2014 | 6 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Chemical structure and antioxidant activity of a new exopolysaccharide produced from Micrococcus luteus Chemical structure and antioxidant activity of a new exopolysaccharide produced from Micrococcus luteus](/preview/png/2087895.png)
An exopolysaccharide (EPS) reaching a maximum of 13 g/L was isolated from Micrococcusluteus by ethanol precipitation. The crude EPS was purified by chromatography on DEAE-cellulose and Sephacryl S-200, affording a polysaccharide active fraction (AEP) with a molecular weight of ∼137 kDa. AEP was investigated by a combination of chemical and chromatographic methods including FTIR, HPLC, periodate oxidation, methylation and GC–MS. Data obtained indicated that AEP was composed of mannose, arabinose, glucose and glucuronic acid in a molar ratio of 3.6:2.7:2.1:1.0, respectively. The main backbone consists of mannose units linked with (1→6)-glycosidic bonds and arabinose units linked with (1→5)-glycosidic bonds. There is a side chain consisting of mannose units linked with (1→6)-glycosidic bonds at C3, when all glucose and most of glucuronic acid are found in the side chain. The in vitro antioxidant assay showed that AEP possesses DPPH radical-scavenging activity, with an EC50 value of 180 μg/mL.
Journal: Journal of Genetic Engineering and Biotechnology - Volume 12, Issue 2, December 2014, Pages 121–126