Screening for Biosurfactant Production from Lactic Acid Bacteria isolated from African fermented milk ‘Wara’

Abstract

Lactic Acid Bacteria (LAB) from ‘wara’, an African fermented milk (cheese), was screened for the production of surface-active agents (biosurfactants) from five species of Lactobacillus: Lactobacillus plantarum, Lactobacillus fermentum, Lactobacillus brevis, Lactobacillus casei, and Lactococcus lactis using red blood cell haemolysis test, emulsification index, and oil spreading assay. Lactobacillus fermentum and Lactobacillus brevis showed the largest zones of haemolysis when screened on blood agar. The highest emulsification index of 20% was recorded by Lactobacillus plantarum, while the least emulsification index of 11% was recorded for Lactobacillus casei. All the isolates demonstrated surface activity after being grown in 2%, 4%, and 8% glucose and lactose, respectively.