Cultivation of Lactobacillus Plantarum KV1 in whey-containing medium for use as starter in vegetable fermentation

Abstract

Strain KV1 is a lactic acid bacteria isolated from fermented Chinese cabbage.By using the 16S rDNA comparison method, KV1 has been identified as Lactobacillus plantarum. It can inhibit the growth of some other bacteria including the nisin-sensitive L.plantarum TISTR850. KV1 bacteriocin was autoclavable and was resistant to salinity of up to 7% NaCl. The optimum temperature and pH for growth of KV1 were at 35oC and pH 6.0, respectively. A low-cost cultivation medium was developed which contained 25.0% (v/v) whey, 0.2% (w/v) CaCl2, 0.05% (w/v) KCl, 0.05% (w/v) MgSO4.7H2O, 0.5% (w/v) NH4NO3, 0.001% (w/v) FeSO4.7H2O, 0.001% (w/v) MnSO4.H2O and 3% of pre-incubated baker’s yeast in distilled water. After 24 hr, the culture yielded 3.8 x 107 cells/ml and 43.3 mU/ml of phytase. The supernatant of the KV1 culture also contained phytase activity which was most active at 37oC and pH 5.5. Using KV1 as a starter for cabbage fermentation showed rapid reduction in the number of other microbial contaminants and increase in phosphate release from degradation of the antinutritional factor, phytate.