Screening,identification and antioxidation evaluation of functional lactic acid bacteria

To develop functional lactic acid bacteria(LAB) starters,natural fermentation Chinese cabbages in Chengdu were collected and LAB were isolated from the collected samples. 64 isolates were preliminarily identified as lactobacillus by gram staining and catalytic test. Three strains of lactobacillus were screened out with good acid,bile salt and H2O2 tolerance. The antioxidation activity of bacteria,fermentation supernatant and intracellular extract were determined,and the fermentation supernatant showed the best scavenging activity of hydroxyl radical and DPPH radical. The hydroxyl radical scavenging activity of SC608 was significant better than the other two strains(p<0.05). The growth performance of SC608 was 4 h in logarithmic growth phase and12 h in stable phase. API CHL and 16 S r DNA fragment sequencing were used to identifying SC608 and the results indicated that SC608 was a strain of Lactobacillus plantarum. To sum up,the Lactobacillus plantarum SC608 was an ideal strain to develop LAB starter with potential antioxidative activity.