## 1 Introduction
However, while refrigeration is effective against mesophilic pathogens, it is unable to slow down the development of a psychrophilic microorganisms such as listeria which survives and grows at 2-4 \({}^{\circ}\)C. For this reason, most current research is aimed at identifying natural additives that can contribute to overcoming this problem [18; 19]. Following the ever-increasing demand from consumers for foods free from chemical preservatives, while also wanting to guarantee quality and safe products, many recent studies have been oriented towards a bio-preservation approach. Bio-preservation is a technique of food preservation in which the antimicrobial potential of selected microorganisms, their metabolites or other natural substances against spoilage and pathogenic bacteria are exploited. Notably, the antimicrobial properties of biomolecules (bacteriocins) produced by Lactic Acid Bacteria (LAB), and of plant-derived compounds such as essential oils [20], have been widely investigated. LAB possess a major potential for use in bio-preservation. They are commonly used in food fermentation, may produce several metabolites with beneficial health effects, and thus are generally recognized as safe (GRAS). LAB exert strong antagonist activity against many related and unrelated microorganisms, including food spoilage and pathogenic bacteria such as _Listeria_ and _Staphylococcus_ spp. The antagonistic effect of LAB is due to lowering the pH of the food, the competition for nutrients, and the production of inhibitory metabolites such as organic acid (lactic acid or acetic acid), hydrogen peroxide and antimicrobial peptides such as bacteriocins active against bacterial pathogens [21]. The beneficial characteristics of Essential Oils (EOs) have long been known and have attracted the attention of researchers for their biological properties, such as anti-inflammatory, antioxidant, fungicidal, anticancer and antimicrobial activities. Their wide range of antimicrobial activity, in particular, is extensively studied in the food field, as they are natural products endowed with many characteristics that make them suitable for food preservation [22]. EOs are volatile compounds of vegetable origin produced by plants as defensive agents against herbivores, insects and phytopathogenic microorganisms. The discovery of the inhibitory activity of EOs against human pathogens has also led to the development of numerous studies on their mode of action. Interaction with the microbial cell membrane seems to be the main target of the EOs [23; 24; 25]. The damage of this microbial structure is the main cause of the growth inhibition of some Gram-positive and Gram-negative bacteria, which, however, show a differential sensitivity to these compounds, being more marked in Gram-positive pathogens, including _L. monocytogenes_[26]. A further step forward was taken when different categories of these natural antimicrobial compounds were added to edible films and coatings, leading to significantly improved antimicrobial properties of packaging [27; 28; 29]. Both companies and research in the food industry are increasingly aiming at developing packaging materials of natural origin, which are made with renewable polymers, derived from by-products, biodegradable and/or produced in total respect for the environment [30]. Moreover, the study of edible packaging for use in fresh foods aligns with this trend, where such materials can represent an edible barrier capable of prolonging the preservation of fresh foods [31; 32]. Edible coatings or films may be a new green preservation method, notably if they are based on the addition of natural substances which make it possible to reduce the use of synthetic polymers. Therefore, bacterios, EOs and edible coatings represent a natural promise in food preservation and the food industry to reduce the addition of chemical preservatives and antibiotics.