| Lactic acid bacteria（LAB） can produce superoxide dismutase, glutathioneperoxidase, catalase and NADH in the fermentation process, which makes LAB hadability of fighting against cancer and enhancing immunity. Probiotics containing LABhave a wide range of applications in breeding, dairy and pharmaceutical industries.The anti-oxidation properties of samples treated by ultrasonic cells brokenextract apparatus and untreated samples was studied. Firstly, the scavenging ratio ofeach samples to·OH was mensurated by using the method of deoxyriboset. Thefermentated broth after being disposed of strain1had the highest scavenging ratioto·OH which was83.4%, while the others had none.Secondly, the scavenging ratio of each samples to O2· was measured by usingthe method of pyrogallol oxidation·. In the system of2.5mmol/L pyrogallol, brokencell treated by ultrasonic cells broken extract apparatus of strain1, fermentation brothafter being treated of strain5, and unbroken cell of strain34had the highestscavenging ratio to O2·, which were96.5%,86.3%and88.8%, respectively.In the system of0.12mmol/L DPPH，the highest scavenging ratio to DPPH ofstrain1, strain5, strain34were supernatant treated unbroken cell and unbroken cell,respectively, the highest scavenging ratios are82.8%,92.6%and70.4%, respectively.In the respect of anti-lipid peroxidizing property, the lipid was5%linolic acid,then detect the scavenging ratio to linolic acid. The highest scavenging ratio to linolicacid of strain1, strain5, strain34were all broken cell treated by ultrasonic cellsbroken extract apparatus, and the scavenging ratio were5.6%,10.1%and7.0,respectively.In the system of5%DTNB, the contents of TTG in cell-free extracts of strain1,strain5, strain34were5.0×10-6mol/L,6.6×10-6mol/L and3.4×10-6mol/L,respectively.The contents of SOD, GSH-PX in samples were detected by elisa. The highestcontents of SOD of strain1, strain5, strain34were all in supernatant, the contentswere3.05U,3.65U and3.28U, respectively; the highest contents of GSH-PX ofstrain1, strain5, strain34were cell, cell and supernatant, respectively, the contentswere194.52U,124.68U and49.71U, respectively.In the modified MRS of100μg/mL Cholesterol and0.3%Oxgall, the removalratio to Cholesterol of strain1, strain5, strain34were41.67%,17.67%and2.65%,respectively.In the simulational environment of the tolerance to acid, strain5was strongerthan the other two strains. In the pH2MRS broth, the colonies of strains5was9×108CFU/mL after5h; in the simulational environment of the tolerance to bile salts,strain34was stronger than the other two strains.The colonies of strains34was6.5×108CFU/mL in the group of0.4%, Both colonies were higher than the criticalvalue （1.0×106CFU/mL）which was the bottom colonies of LAB in the intestine. |
