Biological characteristics and safety evaluation of five Lactobacillus plantarum strains

In this paper, five Lactobacillus plantarum strains isolated from different sources were detected for acid production, bacteriostasis, acid resistance, bile salt resistance, antibiotic resistance, hemolysis and biological amine formation. The results showed that five strains exhibited the higher ability of acid production and bacteriostasis, with a significant difference between each other ( p < 0.05) . The survival rate of two hours, the acid resistant tests presented a higher survival rate of 85.67% ⁹8.00%, there was significant difference between PBIL1-002 and other strains ( p < 0.05) , whereas the bile salt resistance exhibited a lower survival rate of 21.17% ~ 51.20%, the difference between some strains was significant ( p < 0.05) except for PBIL1-002 and PBIL1-006.The five strains were frequently resistant to streptomycin and vancomycin, PBIL1-009 and PBIL1-018 were resistant to cotrimoxazole, PBIL1-006 and PBIL1-009 were resistant to gentamicin.The hemolysis tests showed that the five strains had no hemolytic ability.The qualitative test of amine formation showed that PBIL1-009 strain could produce spermine metabolism, PBIL1-018 strain could produce spermine and tyramine metabolism. The results suggested that the biological and safe characteristics of the different source strains were certain differences.In this way, it was necessary to select the strains with better biological and safe characteristics in the production.