Screening and characterization of lactic acid bacteria from animal faeces for probiotic properties

Abstract

Twenty-two bacterial isolates from wild elephant faeces and 4 isolates from buffalo faeces in Thailand were investigated for probiotic properties and their lactic acid production. On the basis of their phenotypic characteristic clustering and 16S rRNA gene sequence analysis, the isolates were divided into seven groups. Group I (10 isolates) was identified as Enterococcus hirae, group II (4 isolates) as E. avium, group III (3 isolates) as Pediococcus pentosaceus , IV (3 isoaltes) as P. acidilactici, group V (3 isolates) as Lactobacillus pentosus, group VI (1 isolate) as Lactococcus garvieae and group VII (2 isolates) as Weissella paramesenteroides. All of the bacterial isolates were examined for their potentially probiotic properties in acid and bile tolerance as well as in inhibition of cancer cells proliferation by MTT assay. Although the isolates showed no significant effects on human monocytic U937 cells and colon carcinoma Caco-2 cells proliferation, P. acidilactici EL8-2 exhibited the ability to tolerate in the acidic conditions and bile salts. Therefore, P. acidilactici EL8-2 may be regarded as probiotic strains. For lactic acid fermentation with glucose, it was found that E. hirae BF14-1 produced 100% optically pure L(+)-lactic acid while W. paramesenteroides BF13-3 produced 99.79% D (-)-lactic acid.