Studies on the Enhanced Physiological Activities of Mixed Lactic Acid Bacteria Isolated from Fermented Watery Kimchi, Dongchimi

Abstract

The aim of this study was to investigate the efficacy of enhanced physiological activities in cultures isolated from Korean fermented watery Kimchi, Dongchimi, of single lactic acid bacteria (LAB), and when these three are mixed LAB as probiotics. Using the BIOLOG system and 16S rRNA sequencing, the isolates were characterized, and identified and assigned to Leuconostoc mesenteroides DK-3, Leuconostoc dextranicum DK-6, and Lactobacillus curvatus DK-13, respectively. Growth rate and pH changes, production of organic acids as metabolites, and physiological activities of the single and mixed LAB cultures, were monitored and compared. In mixed LAB cultures after 72 h of incubation, the maximum concentrations of lactic acid and acetic acid were approximately 340.5 mM and 191.9 mM, respectively, and pH changed from 7.00 to 3.62. Mixed LAB cultures were able to eliminate 96.3% of nitrite. Activities of antioxidant and β-galactosidase were 60.3% and 16.8 units/mg, respectively. Significant antibacterial activity of the concentrated supernatants was demonstrated against several food-poisoning bacteria. Physiological activities obtained from the mixed LAB cultures have been shown to be considerably higher than those of single LAB cultures. In conclusion, these studies demonstrate that compared to the single cultures, all physiological activities in mixed LAB cultures are significantly enhanced.

Hardening Properties of Cheeses by Latilactobacillus curvatus PD1 Isolated from Hardened Cheese-Ddukbokki Rice Cake

“…It is expected that L. curvatus will be dominant in CD sample during cold storage. It has been reported that L. cruvatus DK-13 isolated from watery Kimchi can produce high amounts of lactic acid and acetic acid during growth on MRS broth [ 28 ]. A starter of sausage, L. curvatus 54M16 can grow at a minimum pH of 3.5 at 30 °C.…”