Effect of different test substances from Lactobacillus plantarum SCS2 on blood glucose and oxidative stress in mice

60 male KM mice(4 weeks) of SPF level were randomly divided into 5 groups:normal group(NG),model group(MG),suspension group(TG1),fermentation centrifugal supernatant group(TG2)and cellular content group(TG3).After 3 weeks administration with basal diets,the hyperglycaemia model were established with 70 mg/kg bw of STZ injection for 3 days plus with 1-week high fat and sugar diet. TG1,TG2 and TG3 were administered with 10 mL/kg bw of 10⁸ CFU/mL suspension,fermentation centrifngal supernatant,cellular contents of L. plantarum SCS2 respectively from the fifth week. NG group and MG group were administrated with 10 mL/kg bw of sterilized saline until the end of the experiments. The effect of different test substances on body weight,fasting and postprandial 2 h blood glucose level,sugar tolerance,level of MDA,SOD,GSH and GSH-Px in serum of hyperglycaemia model mice induced by STZ were studied during the experiments. The results showed that fasting and 2 h postprandial blood glucose levels of hyperglycaemia model mice were reduced(p<0.05)and glucose tolerance was improved significantly(p<0.05)by cellular content of L. plantarum SCS2 after five weeks administration compared with MG mice. Meanwhile,the levels of GSH,SOD and GSH-Px in serum were increased significantly(p<0.05)by cellular content of L. plantarum SCS2. These results suggested that bioactive compounds for hypoglycemic effect would be in cellular content of L. plantarum SCS2 and there would have some connection between the bioactive compounds and improvement of oxidative stress level.