Simple and Rapid Extraction of a Bacteriocin Produced by Streptococcus parauberis Z49 from Fermented Cultures

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.

발효배양액에서 Streptococcus parauberis Z49균주가 생산하는 Bacteriocin의 간편한 추출

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.