Evaluation of the Antioxidant Activity of Lactic Acid Bacteria Heat-Killed Cells Derived from Mulkimchi

Abstract

In order to use lactic acid bacteria isolated from Mulkimchi as a raw material for cosmetics, strain screening was carried out. And we measured the antioxidant activity of the lactic acid bacteria heat-killed cells obtained by heating lactic acid bacteria isolated from Mulkimchi. Among lactic acid bacteria derived from Mulkimchi, 41 strains were selected based on the culture suitability such as growth rate and antibiotic resistance. DPPH assay, ABTS assay, nitrite radical scavenging activity assay, and total phenolic contents were measured for 41 strains. Based on Lactobacillus plantarum LP299v, 1 strain was selected through DPPH assay, 1 strain through ABTS assay, 1 strain through nitrite radical scavenging activity assay, and 1 strain through total phenolic contents measurement. Among these, we isolated Lactobacillus sp. P100, which showed excellent antioxidant activity in all experimental methods, and the result of identification through 16s rRNA showed Lactobacillus plantarum. The strain showed 3-10% better antioxidant activity than Lactobacillus plantarum LP299v. And we measured the cell toxicity and anti-inflammatory activity. Lactobacillus sp. P100 showed the lowest cell toxicity and the highest NO production inhibitory rate. In other words, we could isolate lactic acid bacteria that can be used as an antioxidant ingredient in cosmetics from Mulkimchi.