Isolation and identification of lactic acid bacterial strain KJ-108 and its capability for deodorizing malodorous gases under anaerobic culture conditions

A number of different sources, such as composts, leachates, and pig feces samples, were collected from different pig farms in Korea, and several microorganisms were screened for their ability to deodorize the malodorous gases. Consequently, a novel malodorous gases-deodorizing bacterial strain, KJ-108, was isolated, because it was highly abundant in nitrate-supplemented minimal medium (MM-NO₃^-) under anaerobic culture conditions. Airtight crimp-sealed serum bottles containing MM-NO₃^- medium were inoculated with KJ-108. Nitrate concentration was decreased rapidly after 20 h of incubation, and incubation was carried out until nitrite production reached almost zero. Taxonomic identification, including 16S rDNA base sequencing and phylogenetic analysis, indicated that the isolate had 100% homology in its 16S rDNA base sequence with Lactobacillus pentosus. Among the volatile fatty acids, acetic acid contained in large amounts in fresh piggery slurry was decreased by about 40% after 50 h incubation with strain KJ-108. n-Butyric acid, n-valeric acid, and isovaleric acid were gradually decreased, and isobutyric acid and capronic acid were dramatically eliminated at the initial period with the treatment. Moreover, NH₃ removal efficiency reached a maximum of 98.5% after 50 h of incubation, but the concentration of H₂S was not changed.