Abstract Properties of Bifidobacterium spp.: antibacterial, growth in milk and survival during low temperature storage

A.M. Yazid^1*, A.M. Ali², V. Kalaivani¹ and M. Shuhaimi¹

¹Department of Food Technology, ²Department of Biotechnology, Faculty of Food Science and
Biotechnology, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia

(Received 19 January 1998 / Accepted 24 July 1998)

Abstract.
Eighteen strains of bifidobacteria obtained from ATCC were tested for their inhibitory activity against selected pathogenic microorganisms by using double layer assay method. The results show that bifidobacteria were able to inhibit Pseudomonas aeruginosa, Bacillus megaterium, B. licheniforms, B. subtilis, B. sphaericus, Escherichia coli, Listerm monocytogenes and Salmonella enteritidis, All the tat get organisms showed different sensitivity to different strains of bifidobacteria. The ability of Bifidobacterium strains to grow in milk and their viability in acidified milk during storage were studied by culturing the bifidobacteria. into sterile reconstituted skim milk. The growth was observed by recording the pH and curd formation. B. bifidum, B. breve, B. infantis; and B. longum grew well in milk, forming curd in less than 24 hours. Whereas, B. adolescentis, B. pseudocatenulatum B. asteroides, B. angulatum and B. indicum showed very poor growth in milk. Four strains (B. adolescentis ATCC 11146, B. breve ATCC 15698 and 15701, and B. infantis ATCC 17920) had survival of more than 90% of the initial inoculum after 5 weeks of storage in acidified milk. Strains of B. asteroides ATCC 25909 and 25910 (isolated from honeybees) had survival of 83.2% and 87.8% respectively whereas the survival of B.bifidum was 73%. Only seven out of fourteen strains tested survived low temperature storage in acidified milk.

Keywords: bifidobacteria, probiotic, antibacteria growth, storage