New antimicrobial ingredients

Overlooked and underused

Bio-preservatives are antimicrobial compounds from plants, animals, and microorganisms that inhibit microorganism growth and enhance food’s microbial durability and quality during storage. Although non- toxic, safe (GRAS), biocompatible, and degradable, they are still vastly overlooked and underused. Some of the reasons are price, stability, and negative impact on organoleptic properties. However, innovative solutions like encapsulation in nanovesicles improve natural compounds’ efficacy and organoleptic properties. Combining novel technologies with traditionally used natural compounds is leading to their re-discovery.

Plant-based

Plant-derived products have been used in medicine and food preservation since ancient times. Well-known spices and herbs extracts, like clove, oregano and cinnamon and essential oils of garlic, rosemary and thyme, prevent oxidative spoilage. The antimicrobial efficacy of these products is attributed to synergism with numerous plant secondary metabolites used by plants as protective agents against pathogens.

The content of these compounds in extracts and oils will depend on many things: from geographical and climate factors to extraction technologies and solvents used. The advance of technology has led to more efficient extracts and formulations appropriate for industrial application.

From animals

Animal-derived antimicrobial proteins are purified from the sources or produced recombinantly. The main source of antimicrobial enzymes like lysozyme, lactoperoxidase, and lactoferrin is milk. Chitosan is a linear complex carbohydrate made from chitin, the principal constituent in the external skeleton of arthropods and the cell walls of fungi. It has antimicrobial activity itself, but this biodegradable polymer is used to encapsulate and enhance the properties of many other antimicrobials.

Renewed potential

Microbes have always been the primary source of antibiotics, as bacteria produce them to fight against the other bacteria, their competition for nutrients. Of course, traditional antibiotics used in medicine are not approved for use in food preservation, but some microbial products, such as bacteriocins, are acceptable and useful. Even the whole microorganisms, lactic acid bacteria or yeasts, compete with pathogenic bacteria and thus, prevent their growth.

Antimicrobial ingredients from plant, animal, and microbial sources are re-discovered and innovated constantly. With the progress of modern extraction, delivery, and encapsulation technologies, they will be used not just to improve our medicines but also to improve our food.