Grapefruit extract rich in functional substances adjusting pH 5.0 and adding sucrose (final concentration, 2%) was fermented by Leuconostoc mesenteroides CJNU 0147 strain, consequently prepared a fermented grapefruit extract containing dextran. As a result of analyzing the growth inhibitory effect on gut harmful bacterium Clostridium difficile strain using the prepared fermented grapefruit extract, the viable cell count was significantly reduced (p<0.05 vs. control for 0.5 brix as a final concentration; p<0.001 vs. control for 1.0 brix). On the other hand, the proliferative ability of the extract for Bifidobacterium breve strain, which is one of the species of the genus Bifidobacterium well known as human gut beneficial bacteria, was confirmed (p<0.001 vs. control for both 0.5 and 1.0 brix). These results indicate fermented grapefruit extract with Leu. mesenteroides CJNU 0147 strain inhibits the growth of gut harmful bacterium C. difficile and promotes the proliferation of beneficial bacterium B. breve and is expected to be used as a functional food material for gut health.

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References

• 오승준(한국교통대학교 생명공학전공) | Seung-Jun Oh (Major of Biotechnology, Korea National University of Transportation, Jeungpyeong 27909, Republic of Korea)
• 김자이(한국교통대학교 생명공학전공) | Ja-I Kim (Major of Biotechnology, Korea National University of Transportation, Jeungpyeong 27909, Republic of Korea)
• 김혜련(한국식품연구원 전통식품연구단) | HyeRyun Kim (Research Group of Traditional Food, Korea Food Research Institute, Wanju 55365, Republic of Korea)
• 문기성(한국교통대학교 생명공학전공) | Gi-Seong Moon (Major of Biotechnology, Korea National University of Transportation, Jeungpyeong 27909, Republic of Korea) Corresponding author