Abstract

Adherence of probiotic bacteria to intestinal epithelium is found to be the most principal characteristics among the various physiological functionality. This study was conducted to investigate the effect of bifidobacterial growth properties and condition on the Caco-2 cell adherence and to construct a basic data on adherence-related research. Among 20 strains of bifidobacteris tested, when measured by cell surface hydrophobicity(CSH) and cell agglutination(CA), Bifidobacterium bifidum ATCC29521, Bif. adolescentis K8, and Bif. infantis K9 were selected. Using these strains, variations of Caso-2 cell adherence depending upon experimental condition were analyzed. The results obtained are as follows : Even though Bif. bifidum ATCC29521, Bif. adolescentis K8, and Bif. infantis K9 reached more 85% cell surface hydrophobicity there was no significant difference in cell agglutination, when reached 31.54$\pm$0.54mg/ml. By direct count method for adherence, viable cell count of M3, K1, K2, K8, K9 and K10 reached more 100 counts per 100 Caco-2 cells. When Bif. bifidum ATCC29521, Bif. adolescentistis K8, and Bif. infantis K9 were used to compare the adherence depending upon viable cell counts, reaction time, and growth phase, the more viable cell count, and the more adhered cell counts, the less adherence percentage. In addition, there was no difference in adherence percentage of bifidobacteria when bifidobacteria was incubated from 1 to 8 hrs after Caco-2 cells already formed monolayer. Considering of the effect of growth phase of bifidobacteria on adherence variation, all strains showed the highest adherence during the early stage of stationary phase. In conclusion, adherence of bifidobacteria was affected by strain specificity, viable cell count, and growth activity.

Keywords

• bifidobacteria;
• Caco-2 cell;
• adherence;
• factors