The growth characterization and enzyme productivity of halotolerant microorganisms isolated from the Nakdong River estuary wetland in Korea were investigated in this study. The isolation of halotolerant microorganisms was carried out through their cultivation at 37oC for several days using a marine agar medium. After a single-colony isolation, 16 pure colonies were obtained, and phylogenetic analysis was done using 16S-based ID service in the EzBioCloud database. The isolated strains were divided into 3 phyla, 5 families, 7 genera, and 13 species. Possible industrial applications of the strains were confirmed upon testing for amylolytic, lipolytic, and proteolytic activity to confirm the possible production of hydrolytic enzymes, growth at a pH range of 5 to 9, and various salt concentrations being tested. Thirteen strains possessed at least one enzyme activity, and 5 strains possessed 2 enzyme activities. Eight strains could tolerate up to 10% NaCl concentration. This result indicated that isolated strains had shown the possible application in food and cosmetic industries. Therefore, this study would contribute to securing domestic biological resources and improving hydrolytic enzyme activity using these strains.

The salinity of the brining solution for preparing kimchi imparts saltiness to kimchi, and affects its overall taste. In this study, the changes in the overall taste and quality of kimchi depending on the salinity of the brining solution (6% and 12%) were investigated. The salinity of kimchi brined in 6% NaCl solution was approximately 1.3%, and its umami (2.22±0.22) was lower than that (2.96±0.16) of the conventional kimchi, brined in 12% NaCl solution. In contrast, its bitterness (-3.77±0.05) was higher than that of the conventional kimchi (-4.48±0.12). The sensory evaluation results showed that the overall taste score of the low-salinity kimchi (2.8±0.4) was significantly lower than that of the conventional kimchi (4.5±1.1). To overcome the deterioration in the overall taste, a taste enhancer with a sea tangle extract and anchovy extract was added to the low-salinity kimchi. The overall taste score (4.4±1.2) of the seasoned kimchi, which is the low-salinity kimchi supplemented with the taste enhancer, was comparable to that (4.5±1.1) of the conventional kimchi, while maintaining a salinity of 1.7%. This study demonstrated the benefits of proper taste enhancer for improving the taste of low-salinity kimchi.

Oligosaccharide-producing lactic acid bacteria were isolated from young radish and identified as Weissella cibaria YRK005. Oligosaccharides from W. cibaria YRK005 were purified using size-exclusion high-performance liquid chromatography, and their structure was determined. The oligosaccharides consisted of glucose only, 1 H-nuclear magnetic resonance analysis revealed that the oligosaccharides consisted of 93.8% α-1,6 glycosidic linkages and 6.2% α-1,4 glycosidic linkages, and molecular weight was determined to be 1.1210 2 Da. When the oligosaccharides' prebiotic effect on probiotic strains was examined, the oligosaccharides promoted the growth of four probiotic strains, Bifidobacterium adolescentis, Lactobacillus acidophilus, Lactococcus lactis, and Lactobacillus pentosus, compared to fructo-oligosaccharides as a reference. These results indicated that oligosaccharides from W. cibaria YRK005 could be used as potential prebiotics.

박테리오신은 다양한 식품에서 천연 보존제로 그리고 항생제 대체제로 잠재력을 가지고 있다. 그러나 박테리오신의 다단계 정제 공정은 높은 생산 비용을 야기하여 상업적 이용 등 소비자 접근성에 장애요인이 되고있다. 식품 등 일부 산업 분야에서 활용하기 위한 박테리오신의 순도는 그리 높지 않아도 되며, 이에 따라 정제 공정을 간소화하여 생산 비용을 낮추고 공정 효율성을 강화할 수 있다. 이러한 관점에서 박테리오신 등에 적용할 수 있는 수성- 이상계 시스템(ATPS)은 높은 정제 수율과 빠른 처리 시간으로 인해 산업분야에서 하부 공정 처리 기술로 적절한 대안이 될 수 있으며, 고분자 수용액이 70~90% 물로 이루어진 친환경적 기술로서 환경보호에도 도움을 줄 것으로 전망된다.