Effect of sodium L-glutamate on growth and survival of Lactobacillus brevis NCL912 at different acidic pH

Abstract

Lactobacillus brevis NCL912 is a high γ-aminobutyric acid-producing strain isolated from fermented vegetables. In the present study, the growth and survival of L. brevis NCL912 were investigated in media with or without sodium L-glutamate at different acidic pH levels. L. brevis NCL912 was incubated in acid-modified MRS broth with or without sodium L-glutamate. The results show that L. brevis NCL912 grows at pH>3.0 in the media with or without sodium L-glutamate, and the optimal growth pH is 5.0. L. brevis NCL912 could be survive for more than 2 h at pH 2.0. The addition of sodium L-glutamate significantly enhances acid resistance and glutamate decarboxylase activity (p< 0.05). L. brevis NCL912 displays resistance to acid stress. Sodium L-glutamate is an important factor for the growth and survival of L. brevis NCL912 at different acidic pH. © Springer-Verlag and the University of Milan 2011.