Streptococcus parauberis Z49가 생산하는 새로운 bacteriocin의 특성을 조사하고 수성 이상계를 사용하여 발효배양액에서 효율적으로 추출하였다. Nisin과 유사한 S. parauberis Z49의 bacteriocin은 $121^{circ}C$에서 15 min 열처리해도 활성이 있었으며, 넓은 범위의 pH (pH 2-12)에서 안정하며, M. luteus, Lactobacillus sp., L. fermentum, E. faecium, L. monocytogenes, and P. fluorescens의 생육을 억제하였다. S. parauberis Z49의 발효배양액에 있는 bacteriocin을 간편하게 분리하기 위한 PEG 600/$Na_2SO_4$ 수성 이상계의 최적조건은 PEG 600 15%, $Na_2SO_4$ 30%, NaCl 8% 이었으며, bacteriocin은 PEG층에서 농축이 되었다.
A novel bacteriocin produced by Streptococcus parauberis Z49 strain was characterized and efficiently extracted from fermented cultures by use of aqueous two-phase systems. The nisin-like bacteriocin, which was active even after a heat treatment at $121^{circ}C$ for 15 min and in the broad pH range from 2 to 12, showed inhibition of bacterial growth of Micrococcus luteus, Lactobacillus spp., Lactobacillus fermentum, Enterococcus faecium, Listereia monocytogenes, and Pseudomonas fluorescens. Optimal conditions of PEG 600/$Na_2SO_4$ aqueous two-phase systems for the simple and rapid extraction of a novel bacteriocin were determined to be PEG 600 15%, $Na_2SO_4$ 30%, and NaCl 8%, where the bacteriocin was concentrated in PEG layer.
