논문 상세보기
pp.211-218
이 연구는 자돈의 분변에서 분리된 Enterococcus faecim 193이 생산한 박테리오신을 부분정제하고 그 특성을 파악하여 천연 식품보존제 또는 첨가제로서의 이용가능성을 알아보고자 실시되었다. Enterococcus faecium 193의 배양시간에 따른 항균활성을 측정한 결과 항균활성은 3시간째부터 나타나기 시작하여 12시간째에 1280 AU/ml로 최대 활성을 나타내었다. Enterocin 193은 단백질 분해효소(trypsin, pepsin, 및 proteinase K)의 처리에 의해 항균활성이 소실되었으나 넓은 범위의 pH (1-11)와 열처리(121℃, 15분)에 비교적 안정하였다. 또한 50% 농도의 acetone, acetonitrile, chloroform 및 ethanol 등 유기용매에 안정하였으나, 50% methanol을 처리할 경우 항균활성이 50% 감소하였다. 이 박테리오신은 황산암모늄 침전, 소수성 크로마토그래피와 젤 여과 크로마토그래피에 의해 정제되었고 specific activity는 14.8배 증가하였다. SDS-PAGE에 의해 측정한 이 단백질의 분자량은 약 5 kDa이었다.
This study was conducted to investigate the possibility of using E. faecium 193 or its bacteriocin as natural food preservative or feed supplement. E. faecium 193 was isolated from fecal samples of piglets for its strong inhibition activity against Listeria monocytogenes.. During growth of E. faecium 193 in MRS broth at 37°C, inhibition activity of culture supernatant began to appear after 3 hours and increased to maximun value of 1280 AU/ml after 12 hours incubation. Enterocin 193, a bacteriocin produced by E. faecium 193, was sensitive to proteolytic enzymes such as trypsin, pepsin and proteinase K, active over a wide range of pH being most stable at a pH between 1 and 6, and resistant to heat (121°C, 15 min). The bacteriocin was very stable to the treatment with solvents such as chloroform, ethanol, acetone and acetonitrile, but its activity was decreased by 50% after being treated with 50% methanol. Enterocin 193 was purified by ammonium sulfate precipitation, hydrophobic chromatography and gel filtration with 14.8-fold increase in specific activity, and its molecular weight was determined to be 5 kDa by SDS-PAGE.
