In modern societies, conscious consumers demand healthy, fresh and natural foods devoid of added chemical preservatives and stabilizers. The use of lactic acid bacteria (LAB) to preserve food is one of the oldest and best characterized approach. Production of organic acids is the main feature LAB use to outcompete spoilage organisms, but several other mechanisms have been demonstrated. In this review, a critical overview of the mechanisms used by LAB to inhibit spoilage organisms will be presented. Discrepancies between the concentrations of compounds resulting from LAB activity and their inhibitory amounts are discussed. Technical limitations hindering discoveries in this field as well as future trends in the application of LAB solutions to food bioprotection will be covered, including antifungal peptides and competitive exclusion.

Since the establishment of the ‘Tunisian Chemical Group’ in Gabes city, Tunisia, no serious investigations were carried out about the heavy metal pollution in Gabes gulf. In the present study, the contents of four heavy metals were assessed in four mollusk species (two gastropods, Gibbula ardens and Patella caerulea, and two bivalves, Pinctada radiata and Pinna nobilis), collected from twelve coastal stations. The results obtained showed generally that high concentrations of heavy metals were recorded in the central area of Gabes gulf, nearer to Gabes city; the low concentrations were in contrast found at the edges of this gulf, which is probably due to the chemical pollution generated from the huge industry of phosphoric acid in Gabes city. Comparing the results found with the four examined species, the lowest concentrations were noted with the two bivalve species P. radiata and P. nobilis. The highest heavy metals’ concentrations, noted during this study, are comparable to the findings of other authors in other areas, but they are considerably beyond the standards. A remediation action is necessarily needed either by reducing the amount of heavy metals in the phosphgypums quantities thrown directly in the sea or by stopping completely this harmful industry to protect the marine life in the area. A remediation action is necessarily needed to protect the marine life in the area.