Antibacterial Activity of Bees Gut Lactobacilli against Paenibacillus Larvae In Vitro

The aim of this study was to evaluate antimicrobial activity of bees gastrointestinal Lactobacillus spp. of against Paenibacillus larvae. Content of the intestinal tract was cultured for isolation of Lactobacillus spp. Gut homogenates were plated on de Man, Rogosa and Sharpe agar (MRS, Oxoid) plates and incubated for 48-72h at 30°C anaerobically. Then, the identification of isolates with MALDI-TOF MS Biotyper was done. The bacterial strains Lactobacillus gasseri, L. amylovorus, L. kunkeei, L. fructivorans, Paenibacillus larvae were isolated from gut content of bees. The disc diffusion method was used for the determination of antimicrobial activities of the Lactobacillus supernatant against two strains of Paenibacillus larvae. The best antimicrobial activity of Lactobacillus against Paenibacillus larvae from gut was found in L. gasseri supernatant. Lesser degree of antimicrobial activity against P. larvae was found in L. kunkeei supernatant. The strongest antibacterial activity against P. larvae CCM 4438 was found in L. gasseri and L. amylovorus and the least antibacterial activity was found in L. fructivorans.