Probiotic Properties and Physicochemical Potential of Lactic Acid Bacteria Isolated from Moroccan Table Olives

Background: Lactic Acid Bacteria are a group of Gram-positive bacteria which are widely used in the food industry as organic ferments called starter cultures. In this study, Enterococcus faecium, Leuconostoc mesenteroides, Lactococcus lactis, Weissella paramesenteroides, and Lactiplantibacillus plantarum isolated from Moroccan table olives were tested for their acquisition of probiotic and technological properties. Methods: The ۵ strains were previously isolated from table olives in ۲۰۱۷. Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometer (MALDI-TOF MS) and intergenic space sequencing were used for molecular identification. Following that, probiotic and physicochemical properties were evaluated, including growth at different pH levels (۲, ۳, and ۱۰), temperatures (۷, ۴۵, and ۵۰ °C), and sodium chloride (NaCl) concentrations (۶.۵ and ۱۸% m/v). Antibacterial activity was tested out against Gram-positive and Gram-negatives bacteria. Results: The ۵ strains (E. faecium ۱۶۸, L. lactis ۹, L. plantarum ۱۱, L. mesenteroides ۶۲, and W. paramesenteroides ۳۶) showed an ability to grow at low temperatures (۷ °C). L. lactis ۹ and L. plantarum ۱۱ showed higher acid (pH ۲) and salt (۱۸% NaCl) tolerances. In addition, L. lactis ۹ and L. plantarum ۱۱ exhibited the highest level of free radical scavenging activity after ۴۸ h of incubation, respectively). L. plantarum ۱۱ and E. faecium ۱۶۸ showed the highest antibacterial capacity. However, E. faecium ۱۶۸ and W. paramesenteroides ۳۶ demonstrated better and more rapid acid production capabilities. Conclusion: L. plantarum ۱۱, E. faecium ۱۶۸, and W. paramesenteroides ۳۶ were considered the best candidates as probiotic cultures for further in vivo studies and functional food product development. DOI: ۱۰.۱۸۵۰۲/jfqhc.۹.۳.۱۱۱۵۵