Human health benefits, antimicrobial properties and the future of phenolic compounds as preservatives in the food industry

Abstract

Phenolic compounds are found in fruit, vegetables, nuts, seeds, stems and flowers as well as tea, wine, propolis and honey, and represent a common constituent of the human diet. Dietary flavonoids have attracted interest because they have a variety of beneficial biological properties, which may play an important role in the maintenance of human health. Flavonoids are potent antioxidants, free radical scavengers and metal chelators; they inhibit lipid peroxidation and exhibit various physiological activities including anti-inflammatory, antiallergic, anticarcinogenic, antihypertensive, antiarthritic and antimicrobial activities. Consumption of phenol-rich beverages, fruit and vegetables has commonly been associated to a reduction of the risk of cardiovascular diseases in epidemiological studies and the regular consumption, during several weeks or months, was shown to reduce cholesterolemia, and oxidative stress. The total polyphenols amounts determined from the same plant and their corresponding antioxidant and antimicrobial activities may vary widely, depending on extraction conditions applied. Food contamination and spoilage by microorganisms are a serious problem because they have not yet been brought under adequate control despite the news preservation techniques available. Food-borne illness resulting from consumption of food contaminated with pathogenic bacteria has been of vital concern to public health. Unfortunately there is a dramatic increase throughout the world in the number of reported cases of food-borne illness. To reduce the incidence of food poisoning and spoilage by pathogenic microorganisms many synthetic chemicals were utilized. The exploration of natural antimicrobials for food preservation receives increased attention due to consumer awareness of natural food products and a growing concern of microbial resistance towards conventional preservatives. The use of phenolic compounds as antimicrobial agents would provide an additional benefits, including dual-function effects of both preservation and delivery health benefits. Knowing the antimicrobial effect of the phenolic compounds from vegetables on the principal pathogenic microorganisms from the different foods, it is possible to search strategies to combine the synergic antimicrobial effects of phenolic compounds with their natural biological properties. The results will permit to formulate new products to be used as food preservatives or to be included in the human diet.