Some probiotic properties of <i>Lactobacillus</i> species isolated from honey and their antimicrobial activity against foodborne pathogens

Abstract

Lactobacilli commonly used as a probiotic and they can be isolated from various sources such as fermented foods and gastrointestinal tracts of humans and animals. The aims of this study were isolation and identification of lactobacilli from honey and investigation of some probiotic properties and antimicrobial effects against foodborne bacterial pathogens. A total of 88 honey samples were collected from different areas in Iran. About 1.00 g of each honey was cultured in de Man, Rogosa, and Sharpe (MRS) broth and then sub-cultured on MRS agar. The isolates were assessed for probiotic potentials such as tolerance to acid and bile. Then, antimicrobial activity of isolates against seven foodborne pathogens including <em>Listeria monocytogenes</em>, <em>Shigella flexneri</em>, <em>Staphylococcus aureus</em>, <em>Salmonella</em> <em>enteritidis</em>, Enteropathogenic <em>Escherichia</em> <em>coli</em>, <em>Escherichia</em> <em>coli</em> O157 H7 and <em>Bacillus</em> <em>cereus</em> was investigated. From 88 honey samples, 39 isolates were identified by 16S rDNA gene sequencing method. Fructophilic lactic acid bacteria (FLAB) with 29 (74.00%) isolates were dominant identified bacteria (27 <em>L. kunkeei</em> and two <em>Fructobacillus fructosus</em>). Also, four <em>L. plantarum, </em>two L<em>. paracasei, </em>one <em>L. brevis, </em>one <em>L. rhamnosus, </em>one <em>L. casei</em> and one<em> L. fermentum</em> were identified. Two <em>L. kunkeei</em> isolates and one <em>F. fructosus</em> isolate were resistant to acid and bile salt. Two <em>L. rhamnosus</em> isolates and one <em>L. paracasei </em>isolate inhibited all pathogens (100%). This is the first study in Iran that isolated lactobacilli from honey. The FLAB especially <em>L. kunkeei </em>were isolated as dominated species from honey. Some lactobacilli isolates have probiotic potential and may be useful for the prevention and treatment of infections, but more investigations are needed.