Evaluation of Lactobacillus spp. Based on Phenotypical Profile as Direct-Fed Microbial Candidate for Poultry Nutrition

The present study was conducted to isolate, identify and characterize a lactic acid bacteria strain from turkey ileum content (46-day-old). The new strain was phenotypical confirmed as Lactobacillus acidophilus (L. acidophilus) and conserved under the code IBNA 09. Bacterial profile of L. acidophilus was compared with other strains known as L. paracasei CCM 1837 and L. plantarum ATCC 8014, based on cultural, morphological, biochemical and enzymatic activity (amylase and cellulase). The strains appear as Gram positive bacilli, thin, non-spore-forming, isolated, diplo form, in short chains or in small irregular piles on Man Rogosa and Sharp (MRS) broth and agar medium. The identification and biochemical traits were performed by catalase assay, API 50 CHL V 5.1 soft (L. acidophilus biotype 2, 99.9% ID; good identification to the genus L. paracasei spp. paracasei 1 or 3, 48-51% ID; L. plantarum 1, 99.9% ID) and ABIS online (L. acidophilus ~ 88%; L. paracasei spp. paracasei, ~ 90%; L. plantarum, ~91%). The highest total score of extracellular amylase activity was recorded by L. acidophilus IBNA 09 at 24-48 h (5.10 ± 0.176 U/mL, 4.99 ± 0.409 U/mL), follow by L. paracasei CCM 1837(0.12 ± 0.002 U/mL, 0.15 ± 0.001 U/mL). During entire period, cellulase production was observed only for L. acidophilus (0.28 ± 0.019 U/mL), comparative with L. paracasei where the activity was observed in the first 24 h, respectively at 72 h for L. plantarum. These results suggest that L. acidophilus IBNA 09 possesses potential probiotic traits as a suitable candidate for amylase and cellulase production, and starter culture can improve cereal fermentation and the process of digestion in poultry nutrition.