Control of Lactobacillus plantarum contamination in bioethanol fermentation by adding plantaricins

Abstract

Bacteriocin is considered as a potential biological method for controlling bacterial contamination. Plantaricins can inhibit the growth of Lactobacillus species closely related to the producer. In this study, Lactobacillus plantarum ATCC 8014 was co-cultivated with Saccharomyces cerevisiae S288C to mimic the bacterial contamination in industrial bioethanol fermentation. Plantaricins produced by L. plantarum ATCC BAA-793 was added into the co-cultivation system to control L. plantarum 8014 contamination. The final ethanol content and cell number of S. cerevisiae and L. plantarum 8014 were determined to assess the controlling effect. Results showed that plantaricins could effectively control L. plantarum contamination and remarkably reduce the inhibition effect on S. cerevisiae. Furthermore, plantaricins did no harm to the S. cerevisiae growth and bioethanol yield. These results suggested the potential of plantaricins as a novel antibacterial agent for controlling L. plantarum contamination during the bioethanol fermentation.