Influence of Aphanizomenon flos-aquae and two of its extracts on growth ability and antimicrobial properties of Lactobacillus acidophilus DDS-1

•Aphanizomenon flos-aquae (AFA) as prebiotic substrate for L. acidophilus.•Positive effect of media with AFA, Blue Extract, Pure-PC on L. acidophilus growth.•AFA, Blue Extract and Pure-PC maximized antimicrobial activity of L. acidophilus.•AFA and its extracts could be considered for new synbiotic formulation.

The aim of this research was to investigate the effect of Aphanizomenon flos-aquae (AFA) and two of its extracts, Blue extract and Pure-PC on Lactobacillus acidophilus DDS-1 growth ability and antimicrobial activity. The influence of these compounds on the viability and the resistance to simulated gastrointestinal conditions of L. acidophilus DDS-1 was monitored by plate count agar. The antimicrobial activity of cell-free culture supernatants (CFCSs) of L. acidophilus grown with or without AFA, Blue extract or Pure-PC, was determined against Escherichia coli O157:H7 ATCC 35150 and Candida albicans ATCC 14053 by agar well diffusion and time kill-studies. Media supplemented with AFA, Blue extract or Pure-PC, stimulated the growth of L. acidophilus as compared to the standard MRS broth and enhanced the CFCSs antimicrobial effects. The highest stimulation was observed in media containing Pure-PC, that prolonged L. acidophilus growth up to 72 h.Our data could suggest the use of AFA and its extracts as potential prebiotic substratum, while the combination of Pure-PC with L. acidophilus could be proposed to design synbiotic products playing beneficial effects on humans.