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.

발아 커피 생두의 기능성을 향상할 수 있는지 알기 위하여 인체에 유익한 비피도박테리움 3종(B. animalis, B. bifidum, B. breve)을 이용하여 발효 연구를 한 결과 다음과 같은 내용을 알 수 있었다. 발효는 MRS배지에 설탕과 효모추출물을 첨가하여 37oC에서 4일간 실시하였다. 발효 후에도 발아커피 생두중의 카페인의 함량에 변화가 없었다 . 발효과정은 발아 커피의 클로로겐산 함량을 약간 더 높은 상태로 유지하였으며 이 과정에서 균주별 차이는 없었다. 진한 로스팅(230oC, 30분) 조건으로 생산한 원두의 경우 카페인의 함량이 3 0%(w/ w) 감소하였으나 클로로겐산 함량은 95%이상 감소하였다. B. animalis와 B. breve에 의한 발효과정은 발아커피 원두의 항산화 활성의 감소를 저해(70%) 하였다. 종합하면, 비피도박테리아를 이용한 발효 발아커피 생두와 원두가 커피의 우수한 기능성을 여전히 갖고 있음을 알 수 있었다.

The objective of this study was to prepare bioactive ginseng yogurts containing compound K, which is transformed from ginsenosides, and to investigate the compound’s cytotoxicity against tumor cells. Milk containng ginseng was fermented by Bifidobacteria KK-l and KK-2, and their activities for transforming ginsenosides to compound K were measured. Among the tested concentrations of ginseng in the milk, compound K was effectively produced in the 3% and 6% ginseng yogurts fermented for 48 hrs. These fermented ginseng yogurts were extracted with BuOH, and their cytotoxicities against tumor cells were examined. The BuOH extract of the yogurt made from the 3% ginseng milk showed cytotooxic activity against P388 and HeLa tumor cells. However, the nonfermented ginseng milk did not exhibit cytotoxicity against these cells. Therefore, we deem that the ginseng yogurt, which contained compound K, could be developed as a potential fermented drink product.

Aspergillus niger CAD 1의 정제된 β-galactosidase를 이용하여 치즈 유청으로부터 갈락토올리고당을 생산한 다음 장내 유용세균총인 B. infantis KCTC 3127, B. longum KCTC 3128 및 B. bifidum ATCC 11863의 증식 촉진 물질로서의 영향을 조사하였다. B. infantis, B. longum 및 B. bifidum은 37℃에서 배양 6시간 이후부터 대수적 성장에 도달하였다. B. infantis는 배양 24시간 후 대수기말에 도달하였으며, B. longum 및 B. bifidum은 배양 48시간 이후 대수기말에 도달하였다. pH는 배양 6시간 이후에 크게 감소하였다. B. bifidum은 48시간 반응 후 갈락토올리고당과 raffinose 첨가 배지에서 글루코스, 갈락토스 및 락토오스를 첨가한 배지보다 18%, 8% 및 7% 씩 성장이 증가하였다. B. infantis와 B. longum은 갈락토올리고당과 라피노스 첨가 배지에서 48시간 후 글루코스와 갈락토스를 첨가한 배지보다 성장이 6%와 8% 및 13%와 10%씩 성장이 증가하였다.

Lactobacillus acidophilus NCFM, Lactobacillus casei YIT 9018, Bifidobacterium longum 8001, and Bifadobacterium longum 8025 at the level of 10^6 cfu/ml were cultured with 10⁴ cfu/ml of Escherichia colt O157:H7 KSC 109 or Salmonella typhimurium ATCC 14028, in order to verify the effects of lactic acid bacteria and bifidobacteria on the growth of the pathogens. In the mixed culture of lactic acid bacteria with E. colt O157:H7 KSC 109, growth inhibition and atypical microcolonies of E. colt O157:H7 KSC 109 were observed. The pathogens inoculated grew for 5 hours (pH 5.3), by the time L. acidophilus NCFM reached the exponential growth phase, and then the surviving pathogens were decreased to 10¹ cfu/ml after 35 hours. When L. casei YIT 9018 was grown with the pathogens, they grew for 10 hours (pH 4.6), by the time L. casei YIT 9018 reached the end of exponential growth phase, and then the surviving pathogens were decreased drastically. Up to the stationary growth phase of lactic acid bacteria, L. acidophilus NCFM exhibited stronger inhibition against the pathogens than L. casei YIT 9018 did, which might be attributed to its faster growth. Likewise bifidobacteria inhibited the growth of the pathogens. tested, bifidobaceria was weaker in the inhibitory activity than lactic acid bacteria. When Bifidobacterium longum 8001 was cultured with the pathogens, E. colt O157:H7 KSC 109 was gradually inhibited at the stationary growth phase of bifidobacteria, atypical microcolonies were formed on Levine EMB medium after 48 hours, and Salmonella grew up to 10^6 cfu/ml, then was drastically inhibited at the exponential growth phage of Bifxdobacterium longum 8001. But when Bifidobacteriuam longum 8025 was cultured with the pathogens, the pathogens grew to the same level of Bifidobacteriuam longum 8025 after 10 hours, then the surviving pathogens were decreased drastically.