| Isolation, characterization, and evaluation of Bacillus thuringiensis isolated from cow milk |
|
Chang-Hee Kweon1, Sang-Yoon Choi2, Hyog-Young Kwon2, Eun-Hye Kim2, Hyun-Mi Kang1, Jin-San Moon1, Geum-Chag Jang1, Hee-Soo Lee1, Seung-Won Kang1, Jong-Man Kim1, Suhkneung Pyo2, Dong-Kwon Rhee2 |
1Animal, Plant and Fisheries Quarantine and Inspection Agency (QIA)
2School of Pharmacy, SungKyunKwan University |
|
|
| Abstract |
|
Probiotics colonize the intestines and exert an antibacterial effect on pathogens. Therefore, probiotics could be used as a preventive agent against lethal infections. To isolate probiotic microorganisms, 116 bacterial strains were isolated from healthy cow's milk and were subjected to Gram-stain, morphology and biochemical analyses, Vitek analysis, and 16S rRNA analysis. One of the strains identified as Bacillus (B.) thuringiensis 87 was found to grow very well at pH 4.0~7.0 and to be resistant to high concentrations of bile salts (0.3~0.9% w/v). B. thuringiensis was susceptible to the antibiotics used in the treatment of bovine mastitis, yet it exhibited an antimicrobial effect against Staphylococcus (S.) aureus 305. Moreover, it protected mice from experimental lethal infections of E. coli O55, Salmonella typhimurium 01D, and S. aureus 305 through a significant induction of interferon-${gamma}$, even at four-week post-administration of B. thuringiensis. Although oral administration of B. thuringiensis 87 did not provide significant protection against these lethal challenges, these results suggest that B. thuringiensis 87 could be a feasible candidate as a probiotic strain. |
| Key Words:
Bacillus thuringiensis, interferon-${gamma}$, probiotics |
|
PDF Links
Full text via DOI
Download Citation
