Isolation and characterization of potential probiotic Lactobacilli from leaves of food plants for possible additives in pellet feeding

Bacteria strains isolated from plant leaves of papaya, cassava, sugarcane, yam, and taro, were investigated for their potential probiotic properties. Four isolates from food crop plant leaves were identified as Lactobacillus plantarum, Enterococcus faecalis, Lactobacillus paraplantarum, and Weissella paramesenteroides by sequence of 16S rDNA. The five isolates exhibited tolerance to simulated intestinal juices, and these were selected to evaluate their probiotic properties by biochemical characterization and in vivo testing as a pelleted feed additive. All 5 strains were susceptible to Streptomycin, Penicillin, Chloramphenicol, Ampicillin, and Tetracycline, and exhibited antimicrobial activity against Gram-positive Bacilus cereus, Listeria monocytogenes, Staphylococcus aureus, and the Gram-negative Escherichia coli pathogen. Furthermore, the lactobacilli isolates W. paramesenteroides C02, E. faecalis S04, L. paraplantarum P01, L. plantarum T03, and W. paramesenteroides Y05 exhibited rapid growth in skimmed milk with no nutritional supplement to 108 cfu.mL(-1) after 24 h incubation. In vivo analysis of swine feeds after granulation exhibited 109-1010 cfu.kg(-1) of L. plantarum, E faecalis, and W. paramesenteroides, which confirmed the probiotic potential and application of the lactobacilli strains isolated from plant leaves in granulated or pelleted feed as additives.