Intestinal Lactobacillus community structure and its correlation with diet of Southern Chinese elderly subjects

This study aimed to investigate the relationship between the intestinal Lactobacillus species and diet of elderly subjects in a longevity area in Southern China. Healthy elderly subjects ranging from 80 to 99 years old were respectively selected from the regions of Bama and Nanning, Guangxi, China. The nested polymerase chain reaction and denaturing gradient gel electrophoresis (PCR-DGGE) technology was used to analyze the intestinal Lactobacillus community structure. Results showed that Weissella confusa, L. mucosae, L. crispatus, L. salivarius, and L. delbrueckii were the representative Lactobacillus of elderly subjects. Among them, L. crispatus and L. delbrueckii were the dominant Lactobacillus of all species. In comparison to Nanning elderly subjects, the detection frequencies of W. confusa and L. salivarius were significantly increased in Bama elderly subjects (P < 0.01), whereas L. mucosae was significantly decreased (P < 0.01). Interestingly, it was also found that there were 4 kinds of representative Lactobacillus, which were significantly correlated with dietary fiber. W. confusa (P < 0.01) and L. salivarius (P < 0.05) were significantly positively correlated with the intake of dietary fiber, while L. mucosae (P < 0.01) and L. crispatus (P < 0.05) were significantly negatively correlated with the intake of dietary fiber, respectively. Results confirmed that different diets had obvious effects on the intestinal Lactobacillus community structure of elderly subjects in Southern China, which may provide a certain theoretical basis for the elderly's healthy food strategic design and probiotics product development.