Study On The Anti-ultraviolet Damage Activity Of Pantoea Agglomerans TCa-7

The exopolysaccharide is prepared from the fermentation liquid of a Pantoea agglomerans strain TCa-7 with preferred anti-ultraviolet damage activity, which is isolated from a mangrove forest in Futian, south of Shenzhen, China. The part named EPS I with antioxidation activity purify from the aforesaid exopolysaccharide, and the characterization of EPS I is studied. Then its antioxidation activity in vitro and protective effect in several microorganisms is researched and analyzed.(1) The strain that could produce exopolysaccharide with anti-ultraviolet damage activity is selected by two steps. At first, 15 strains of bacteria isolate from plates which are irradiated by UV radiation, then test their UV radiation survival curves, 4 strains of bacteria with high survival rates are selected. Second, the protective effects against ultraviolet and antioxidation activities of fermentation liquids and exopolysaccharide extracts of aforesaid 4 strains of bacteria are tested, results show that the product group of TCa-7 has high antioxidant activity and Anti-ultraviolet damage activity. The colony modality, physiological and biochemical characteristics of strain TCa-7 show that it is a Pantoea agglomerans strain.(2) The exopolysaccharide is extracted from the fermentation liquid of Pantoea agglomerans TCa-7, and the part with antioxidation activity EPS I purify by Sephacryl S-300HR gel column corresponding to a molecular mass: 757kDa determined by GPC technique. EPS I is composed of arabinose, glucose and galactose in the molar ratio of 1.0: 2.2: 2.7, and a little bit mannose. Besides, EPS I contains 75.3% carbohydrate, 13.3% uronic acid and 14.9% protein.(3) The test of antioxidation activity in vitro of EPS I show that it has high activity in a concentration-dependent manner. EPS I quench hydroxyl radicals, superoxide radicals at low amounts, the IC50 of which are 024 and 0.25 mg/ml, respectively; restraining rate to antilipid peroxidation is 30.17% at the content of 0.06 mg/ml. EPS I with a lower concentration has...