2.2. Isolation of lactic acid bacteria (LAB) from kimchi
LAB strains were isolated from six homemade and two commercial kimchi which were collected from different regions in Korea. Each kimchi sample (10 g) and 0.05 M potassium phosphate buffer pH 7.2 (1:1 w/v) were homogenized using a stomacher (LB W400, TMC, Seoul, Korea). One mL of the homogenate was serially diluted with 0.85% saline and 0.1 mL of the dilution was spread on MRS agar (Difco, Detroit, USA) containing 0.02% sodium azide. For each kimchi sample, 4-5 colonies were selected by shape from the MRS plate containing 30–50 colonies after incubation at 37 °C for 24 h (total 38 strains for eight kimchi samples). Among 38 isolates, six strains of homo-fermentative type with active growth were selected and stored at 4 °C for further studies.