The CFS of all the LAB strains assayed showed antilisterial activity on LM1.
By comparison, some strains showed a lower antagonistic effect while others showed none when LAB supernatants were neutralized.
These results agree with those recently reported by Aguilar and Klotz (2010). They reported antimicrobial activity of CFS from Lactobacillus species and found a higher inhibitory effect with untreated supernatants, as compared to neutralized supernatants.