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Vibrio cholerae and Vibrio parahaemolyticus are common pathogens linked to human gastroenteritis, particularly in seafood like shrimp. This study investigated the impact of lactic acid bacteria on V. cholerae and V. parahaemolyticus regarding the production of cadaverine, a concerning compound. V. cholerae NCCP 13589 and V. parahaemolyticus ATCC 27969 were significant producers of amines in experiments conducted using white-leg shrimp (Litopenaeus vannamei) and lysine decarboxylase broth. Notably, the Lactiplantibacillus plantarum NCIMB 6105 and Leuconostoc mesenteroides ATCC 10830 lactic acid bacteria strains demonstrated a pronounced antagonistic effect on the production of biogenic amines by these food-borne pathogenic bacteria. The presence of lactic acid bacteria led to a substantial reduction in cadaverine production in the lysine decarboxylase broth and shrimp extract. The co-culture of two lactobacilli species reduced the cadaverine production in V. cholerae and V. parahaemolyticus by approximately 77 and 80%, respectively. Consequently, the favorable influence of lactic acid bacteria in curbing cadaverine production by food-borne pathogens presents clear advantages for the food industry. Thus, effectively managing these pathogens could prove pivotal in controlling the biogenic amine levels in shrimp.

This study fabricated an OER electrocatalyst with a hierarchical structure by electrodepositing Ni-Fe on NiO. The prepared electrocatalyst exhibited high activity and stability. Furthermore, the OER characteristics of the NiFe/NiO electrode were investigated by changing the metal (Ni and Fe) concentration and Ni:Fe ratio in the plating bath. As the plating bath concentration decreased, NiFe-layered double hydroxide was prominently formed due to an increase in local pH. The electrode obtained using a relatively low plating bath concentration of 130 mM demonstrated high activity with an overpotential of 245 mV and Tafel slope of 27.6 mV dec-1 at a current density of 10 mA/cm2. When the Ni:Fe ratio in the plating bath was adjusted, OER activity increased as the Fe content of the electrode increased to approximately 20.9 at.%, and as the Fe content increased beyond that, the activity gradually decreased. Fe inhibits Ni oxidation and acts as an active site owing to Fe3+ substitution in the γ-NiOOH structure, resulting in increased OER activity. However, when the Fe content was > 29 at.%, the inactive phase γ-FeOOH predominantly grew and the OER activity decreased.