Lactobacillus delbrueckii (L. delbreuckii) is one of probiotic bacteria that can be in the yogurt with Streptococcus thermophilus bacteria. The previous study has found that the intake of yogurt fermented with (L. delbreuckii) can improve the values of immune system parameters that contributed to biological defense in the elderly. Eschericia coli (E. coli) is an opportunistic bacterium in the human gut microbiome. This bacterium can cause gastroenteritis and intestinal infection. In older people, a different gut microbiota composition with the increased certain pathogens was found, as compared to younger people. This may be related to a decrease in immunocompetence in elder people. In this study, we profile the differential gut microbiome in various ages via detection of antibodies to gut bacteria. The lateral flow immunoassay (LFIA), a rapid and low cost method, was constructed to detect the antibodies to gut bacteria in the human sera and saliva. The antibodies to L. delbreuckii or E. coli can be detected in the human sera and saliva by LFIA spotted with bacterial lysates on nitrocellulose membrane. Furthermore, the antibodies to E. coli or L. delbreuckii were higher on older people than young people. In older people, the antibodies to E. coli were much higher than antibodies to L.delbrueckii. On the other hand, electricity produced by L. delbrueckii was significantly higher than that by E. coli. Profiling the antibodies to electrogenic bacteria in the gut of various ages may open a new study of aging.
Keyword : L. delbrueckii,E. coli, LFIA, Aging factor
