Screening and characterization of keratinolytic bacteria from poultry waste fed pangasius (pangasianodon hypophthalmus) farms

Ten poultry waste fed P. hypophthalmus farms were screened for the isolation of keratinolytic bacteria from the aquatic environment. Three isolates namely FWKB1, FMKB1 and FMKB2 were isolated from mud and water with potential keratinolytic activity.It is for thefirst-time presence of keratinolytic microorganisms have been screened from aquaculture environment. Among 116 proteolytic colonies obtained by primary screening only 6.9% has shown keratinolytic activity. Among them 3 isolates have formed clear zone of 1-2cm diameter in feather meal agar plate within 72 hours of incubation. They were further characterised by morphological as well as biochemical characters and confirmed by 16S rRNA sequencing. The isolate FWKB1 was a gram positive, non-spore forming,motile rodsobtained from water sample of Pangasius culture pond and identified as bacteria belong to genus Exiguobacteriumprofundum. Both of the other isolates FMKB1 and FMKB2 were gram positive, motile, spore forming rod shaped bacteria isolated from mud sample of culture ponds and they belongs to the genus Bacillus.As these isolates are being isolated from the culture system itself and having potential keratinolytic activity they may be proposed as environmental probiotics for the recovery of poultry waste fed pangasius farms, which now appearing as poultry waste dumping sites with undegradable chicken feathers streaming over the water resources.