Article info.

ABSTRACT

Received 27 Sep 2016
Revised 08 May 2017

Accepted 31 Oct 2017

The objectives of this study were to select a number of thermotolerant lactic acid bacteria (LAB) for their application in biomass production at high temperature and to study the genetic relation of these selected strains by using 16S ribosomal DNA sequences. All 16 tested strains of thermotolerant LAB were found to possess the antibacterial ability and the capability of bacteriocin production against Bacillus subtilis. As a result, all 16 LAB strains had an antibacterial ability and produced bacteriocin against indicator. Ten selected strains having the strongest antibacterial ability were identified as Lactobacillus plantarum, L. casei, and L. delbrueckii. The L. plantarum L54 was selected for the experiment of the optimum conditions for biomass production because of its strongest antibacterial ability. The diameter of inhibitory zone in “agar spot test” and “well-diffusion agar” were 13.76 mm and 17.33 mm, respectively. Based on statistical analysis, the optimum conditions for biomass production by L. plantarum L54 at 39°C were 5.99% (w/v) of glucose concentration, 6.37% (v/v) of bacterial inoculum concentration, and pH 6.0.

Keywords

Antibacterial activity, biomass, lactic acid bacteria, Lactobacillus plantarum, thermotolerant

Cited as: Thu, H.N.N., Long, B.H.D., Phong, H.X., Zendo, T., Sonomoto, K. and Dung, N.T.P., 2017. Selection of thermotolerant lactic acid bacteria producing high antibacterial activity and production of biomass from tofu sour liquid. Can Tho University Journal of Science. 7: 51-57.