Vibrio parahaemolyticus is one of the leading foodborne pathogens causing seafood contamination. Here, 22 V. parahaemolyticus strains were analyzed for biofilm formation to determine whether there is a correlation between biofilm formation and quorum sensing (QS), swimming motility, or hydrophobicity. The results indicate that the biofilm formation ability of V. parahaemolyticus is positively correlated with cell surface hydrophobicity, autoinducer (AI-2) production, and protease activity. Field emission scanning electron microscopy (FESEM) showed that strong-biofilm-forming strains established thick 3-D structures, whereas poor-biofilm-forming strains produced thin inconsistent biofilms. In addition, the distribution of the genes encoding pandemic clone factors, type VI secretion systems (T6SS), biofilm functions, and the type I pilus in the V. parahaemolyticus seafood isolates were examined. Biofilm-associated genes were present in almost all the strains, irrespective of other phenotypes. These results indicate that biofilm formation on/in seafood may constitute a major factor in the dissemination of V. parahaemolyticus and the ensuing diseases.

Leuconostoc lactis SBC001, isolated from chive, produces glucansucrase and synthesizes oligosaccharides through its enzymatic activity. This study was conducted to optimize oligosaccharide production using response surface methodology, analyze the structure of purified oligosaccharides, and investigate the prebiotic effect on 24 bacterial and yeast strains and the anti-inflammatory activity using RAW 264.7 macrophage cells. The optimal conditions for oligosaccharide production were a culture temperature of 30 °C and sucrose and maltose concentrations of 9.6% and 7.4%, respectively. Based on 1H-NMR spectroscopic study, the oligosaccharides were identified as gluco-oligosaccharides that consisted of 23.63% α-1,4 glycosidic linkages and 76.37% α-1,6 glycosidic linkages with an average molecular weight of 1137 Da. The oligosaccharides promoted the growth of bacterial and yeast strains, including Lactobacillus plantarum, L. paracasei, L. johnsonii, Leuconostoc mesenteroides, L. rhamnosus, and Saccharomyces cerevisiae. When lipopolysaccharide-stimulated RAW 264.7 cells were treated with the oligosaccharides, the production of nitric oxide was decreased; the expression of inducible nitric oxide synthase, tumor necrosis factor-α, interleukin (IL)-1β, IL-6, and IL-10 was suppressed; and the nuclear factor-kappa B signaling pathway was inhibited. In conclusion, the gluco-oligosaccharides obtained from Leu. lactis SBC001 exhibited a prebiotic effect on six bacterial and yeast strains and anti-inflammatory activity in RAW 264.7 macrophage cells.

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Salted shrimp Jeotgal, a favorite in Korea, is raw fermented fish containing 20-30% NaCl, which serves to inhibit its decay for a certain period. However, Bacillus cereus has been detected in commercial salted-fermented shrimp. Therefore, the goal of the present study was to examine the effect of 5-15% NaCl on the inactivation of B. cereus in various salted shrimp stored for two weeks. We determined whether NaCl could affect lactic acid bacteria and pH in salted shrimp during storage. B. cereus significantly (P < 0.05) decreased with increasing NaCl concentration and storage time at 10C. The average B. cereus count steadily and rapidly reduced before and after a 7-day storage period, respectively. Moreover, there was no significant change in the population of lactic acid bacteria and the Hunter color (P > 0.05) during storage periods at 10C. PRACTICAL APPLICATIONSThis study indicates that the use of NaCl at doses of 5-15% could be an effective way to control B. cereus contamination in salted shrimp during storage at 10C. The color measurement degenerated with stepwise decrease in NaCl concentration from 7 days of storage. Therefore, we suggest that salted shrimp containing 5-15% NaCl should be consumed within 7 days.

The shelf life of four different sauces in retort pouches, Gochujang chicken, Kimchi, ham beef, and beef salsa, was examined. Samples of each sauce pouch were stored at 25, 35, and 45°C for 6 months; changes in the chemical were measured, and sensory evaluation was done. Finally, this study predicted the shelf life of products. Concentrations of thiobarbituric acid (TBA) inside the retort-pouched sauces were found to increase over the course of storage. Likewise, the overall pH of the sauces was found to decrease generally. Finally, sensory evaluation, ranked on a 7-point scale, was found to be greater than 5 (''like moderately'') when processed by one of 15 panel. The TBA value was used to estimate the shelf life of the four sauces, which was found to be greater than 3 years for each. Therefore, the use of retort pouches is an effective packaging method for the long-time storage of sauces at temperatures lower than 25°C.