Antibacterial and antibiofilm activity of the bacteriocin-producing strain Leuconostoc mesenteroides CHBY46 isolated from Algerian dromedary milk against Pseudomonas aeruginosa and Staphylococcus aureus biofilms

Abstract

In order to control biofilm formation of pathogenic and spoilage bacteria in foods, some species of Leuconostoc are very important in food industries, as they increase the shelf life of foods during preservation. In this study the strain CHBY46 a bacteriocin-producing strain belonging to Leuconostoc ge-nus isolated from dromedary milk in the south of Algeria was characterized by 16S rRNA gene sequencing and MALDITOF MS mass spectrometry, tested for its antibacterial and antibiofilm activities against Pseudomonas aeruginosa and Staphylococcus aureus. The produced bacteriocin was partially puri-fied with sulfate ammonium precipitation and RP-HPLC. The strain CHBY46 was classified as Leuc. mesenteroides after molecular identification. Among the bacteria tested the pathogens Staph. aureus ATCC 29213 and Ps. aeru-ginosa ATCC 27653 were sensitive to this bacteriocin with 480 AU/ml. Antibi-ofilm activity was investigated by crystal violet assay. The bacteriocin of Leuc. mesenteroides CHBY 46 exhibited significant biofilm inhibition ; 35.58% with Ps. aeruginosa, and 42.11% with Staph. aureus. Tricine-SDS-PAGE analysis of the partially purified bacteriocin indicated a low molecular weight of approximately 3.5 kDa. Therfore, we conclude that bacteriocins from Leuco-nostoc have the potential as a therapeutic strategy against pathogen’s bio-films, which contribute, to bacterial pathogenicity and resistance toward antibiotics or being used in foods as adjunsts to contribute food safety.