The Effects of Pantoea and Kosakonia Isolated from Buckwheat Sprouts on Obese Mice

Objective: This study aims to investigate the effects of surface bacteria of buckwheat sprouts on obesity. We examine whether these bacteria have probiotic properties. Methods: Since P-36 and P-37 strains were present in large amounts on the buckwheat sprouts surface, identification of species was carried out by intestinal bacteria identification kit and 16S rRNA gene analysis. Subsequently, to investigate the biological effects, P-36 and P-37 strains were divided into two groups, heat-treated dead bacteria and untreated viable bacteria, which were then orally administered to obese model mice exhibiting hyperglycemia every other day for a total of 10 times. After administration, BMI and visceral fat mass were measured, and oral glucose tolerance test was conducted to evaluate glucose tolerance; their influence on blood glucose level and insulin resistance (HOMA-IR) was evaluated. Results: The strain P-36 was identified as Pantoea sp., and P-37 as Kosakonia cowanii. In the group of mice administered the living and dead bacteria of P-36 and P-37, the weight gain rate after the administration was low, and the progression of obesity was suppressed. In the oral glucose tolerance test, an improvement of glucose tolerance and a significant suppression of blood glucose level was confirmed at 0 and 15 min in the group treated with viable P-37. In addition, HOMA-IR was improved in mice treated with both viable and dead P-37 bacteria. Conclusion: The mice administered P-36 and P-37 showed a gradual increase in body weight and a decrease in visceral fat percentage. The mechanism leading to improved blood glucose levels observed in mice administered P-37 strain remains unclear at present. The involvement of buckwheat sprouts-derived bacteria in improving hyperglycemia and reducing obesity during a short time will help to discover new probiotics.