Exploring the functional and probiotic potential of bacteriocin-producing lactobacilli from Algerian Kaddid

Research on lactobacilli from traditional food niches have received increasing attention for theirbeneficial properties. In this study, selected bacteriocin-producing lactobacilli strains previouslyisolated and characterized from laboratory-prepared Kaddid were used. The lactobacilli werescreened in vitro for their probiotic potential including inhibition of Listeria (L.) monocytogenesFBUNT biofilm formation, antioxidant capacity and γ-aminobutyric acid (GABA) production.When probiotic features were investigated, surface characterization of bacteriocinogenic lactobacilli revealed most of them as hydrophilic, however Latilactobacillus (Lat.) sakei subsp. sakei K26 exhibited strong auto-aggregative and hydrophobic character with a positive Pearson (r) correlation between the two characteristics. In addition, Lactiplantibacillus (Lpb.) paraplantarum K18 was the most resistant to assayed low pHs and bile salts being able to withstand gastrointestinal tract (GIT) conditions. Variable biofilm formation patterns were displayed by adhesion in polystyrene plates depending on the modified MRS media composition, higher production for Lat. sakei subsp. sakei K26 and Lpb. paraplantarum K18 was found. When bacteriocin-like inhibitory substances were tested against L. monocytogenes biofilm, Lat. sakei subsp. sakei K26, Lat. sakei K25 and Lpb. paraplantarum K18 were the most efficient at reduced the pathogen in correlation with their ability to produce bacteriocins and biosurfactants. Variable free radical scavenging activity (DPPH˙ and HO˙) and anti-lipid peroxidation was found in lactobacilli strains, while GABA production assay showed Lpb. paraplantarum K18 to reach 18.63 mM with a conversion rate of ~6.9% after incubation at 30 ◦C for 15 days. On these bases and together with previous results, the beneficial effect of Lpb. paraplantarum K18 support its potential to be used as functional/probiotic starter culture for the development of new and safety fermented meat products. Fil: Boubakri, Kamel. Yahia Fares University of Medea ; Argelia Fil: Melian, Constanza Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentina