成团泛菌KFS发酵产胞外多糖(EPS)是由葡萄糖和甘露糖组成的均一性杂多糖,重均分子量约为756kDa。以透明质酸和甘油为对照,分别在2种相对湿度环境下考察了EPS的吸湿性和保湿性。基于该EPS较强的抗氧化活性,进一步考察了其对不同菌体的抗辐射保护作用。结果表明:在相对湿度43%和81%的环境中,EPS均显示出较好的保湿活性,吸湿性与透明质酸相似,略低于甘油;EPS对菌体的辐射保护作用与糖溶液浓度和紫外辐照时间呈相关性,当糖溶液浓度为4 mg/mL、紫外辐照5 min时,大肠杆菌、白色念球菌以及金黄色葡萄球菌的存活率分别是48.49%、36.73%、47.5%,明显高于空白对照组的13.68%、13.47%和12.25%。所以,EPS作为天然的保湿剂和抗辐射剂有应用前景。

The EPS produced by Pantoea agglomerans KFS was a kind of homogeneity heteropolysaccharide comprised of glucose and mannose with a molecular weight of 756 kDa. Hygroscopicity and moisture retention ability of the EPS was investigated under two kinds of humidity conditions with hyaluronic acid( HA) and glycerol as references. Given the excellent antioxidant activity of the EPS,UV-irradiation test was also conducted. It was showed that the EPS was superior to other sources in hygroscopicity,similar to HA and lower to glycerol in moisture retention; The UV-irradiation protective effects on cells of the EPS was related to the EPS concentration and UV radiation time. When the UV exposure time reached 5 min,the survival rates of the E. coli,C. albicans and S. aureus in experimental groups with 4 mg / mL EPS were 48. 49%,36. 73% and 47. 5%,remarkably higher than the rates of 13. 68%,13. 47% and 12. 25% in the control groups,respectively. Therefore,the EPS used as a natural moisturizer and anti-radiation material should have a widely application prospects.