Comparison of four methods for identification of bifidobacteria to the genus level

Abstract

The identification of bifidobacteria to the genus level is important for the differentiation of these bacteria from other bacteria occurring in the animal and human intestine. The detection of fructose-6-phosphate phosphoketolase (F6PPK-test) is used traditionally for the identification of Bifidobacterium sp. The original procedure is time consuming and therefore it was modified several times recently. The aim of the present work was to compare the following methods for the genus identification of bifidobacteria: F6PPK-test, F6PPK-test modified by the addition of triton X-100, F6PPK-test modified by the addition of cetridium bromide (F6PPK-CTAB-test), and PCR using genus specific primers. Bifidobacteria isolated from fermented milk products (3 strains), human faeces (6 strains), and animal intestinal tract (2 strains) were tested. All the methods tested proved to be reliable tests for the genus identification of bifidobacteria. The F6PPK-CTAB-test gave the best results. This procedure is quick and does not require any special laboratory equipment.

Keywords

• bifidobacteria
• identification
• fructose-6-phosphate phosphoketolase test
• ctab
• triton x-100
• pcr