Isolation, characterization and molecular identification of potential probiotic lactobacilli from gastrointestinal tracts of Capoeta razii and Aristichthys nobilis

The aim of this study was to isolate and identify Lactobacillus with probiotic potential from gastrointestinal tracts (GIT) of Capoeta razii and bighead carp, Aristichthys nobilis. GIT samples of fifteen bighead carp and sixteen C. razii were collected and homogenized in 0.9% NaCl buffer and cultured on MRS medium. Nine isolates were obtained from C. razii and 18 insolates from bighead carp. The isolates were sequentially subjected to acid- and bile salt-resistance test. Three isolates from C. razii and one isolate from bighead carp were both acid- and bile salt-resistant. These isolates were identified by sequencing 16s rRNA and subjected to BLAST analysis to find the highest similarity in GeneBank. The isolate from bighead carp and two isolates from C. razii were L. plantarum with the highest similarity with strain DR7. One of the isolates from C. razii was L. brevis with the highest similarity with strains 100D8 and BDGP6. Further studies are encouraged to assess these probiotic effects in aquaculture species growth performance and health status