Food consumers and industries urged the need of natural alternatives to assure food safety and quality. As a response, the use of natural compounds from herbs and spices is an alternative to synthetic additives associated with toxic problems. This review discusses the antimicrobial and antioxidant activity of oregano essential oil (OEO) and its potential as a food additive. Oregano is a plant that has been used as a food seasoning since ancient times. The common name of oregano is given to several species: Origanum (family: Lamiaceae) and Lippia (family: Verbenaceae), amongst others. The main compounds identified in the different OEOs are carvacrol and thymol, which are responsible for the characteristic odor, antimicrobial, and antioxidant activity; however, their content may vary according to the species, harvesting season, and geographical sources. These substances as antibacterial agents make the cell membrane permeable due to its impregnation in the hydrophobic domains, this effect is higher against gram positive bacteria. In addition, the OEO has antioxidant properties effective in retarding the process of lipid peroxidation in fatty foods, and scavenging free radicals. In this perspective, the present review analyzes and discusses the state of the art about the actual and potential uses of OEO as an antimicrobial and antioxidant food additives.

Many food preservation strategies can be used for the control of microbial spoilage and oxidation; however, these quality problems are not yet controlled adequately. Although synthetic antimicrobial and antioxidant agents are approved in many countries, the use of natural safe and effective preservatives is a demand of food consumers and producers. This paper proposes medicinal plants, traditionally used to treat health disorders and prevent diseases, as a source of bioactive compounds having food additive properties. Medicinal plants are rich in terpenes and phenolic compounds that present antimicrobial and antioxidant properties; in addition, the literature revealed that these bioactive compounds extracted from other plants have been effective in food systems. In this context, the present hypothesis paper states that bioactive molecules extracted from medicinal plants can be used as antimicrobial and antioxidant additives in the food industry.

There is renewed interest in the antibacterial and antioxidant properties of essential oils as food additives. Among essential oils, cinnamon leaf oil is a potent antibacterial and antioxidant agent; however, the application in food systems can be affected by its volatility. The use of edible films is a good alternative for incorporating antibacterial agents and antioxidants into foods. This study aimed to develop an edible pectin film enriched with the essential oil from cinnamon leaves and prove that this application can increase the antioxidant status and reduce bacterial growth of fresh‐cut peach. Films with different oil concentrations (0.0, 7.3, 15.7 and 36.1 oil g/l) were evaluated regarding eugenol content, thickness, moisture content, water vapour transmission, in vitro antioxidant activity and antibacterial properties of the films. No significant differences were found for the water vapour transmission among the films with different oil concentrations. The higher the added oil concentration the higher the eugenol content and antioxidant capacity; the films with 36.1 g/l were the only materials showing inhibition zones against Escherichia coli O157:H7, Staphylococcus aureus and Listeria monocytogenes. Peaches were positively affected by the coating treatment, increasing its antioxidant status, odour acceptability and decreasing bacterial growth. These results demonstrate that the development of an edible film formulated with cinnamon leaf oil can be useful to preserve fresh‐cut peach quality. Copyright © 2012 John Wiley & Sons, Ltd.

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Pectin-OEO coatings showed antifungal effect and increased the antioxidant activity without negative effects on the sensorial acceptability of tomatoes. © 2015 Society of Chemical Industry.

In the present study total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity and antimicrobial properties of grape (Vitis vinifera var. Red Globe) stem extract is reported. Also, the identification of main phenolic compounds was carried out by UPLC-PAD analysis. TPC and TFC of extract were 37.25 g GAE kg and 98.07 g QE kg, respectively. Extract showed an antioxidant capacity of 132.60 and 317 g TE kg for DPPH and ABTS radical scavenging capacity, respectively. The main phenolic compounds identified were rutin, gallic acid, chlorogenic acid, caffeic acid, catechin and ferulic acid. Extract inhibited the growth of ,, subsp. serovar Typhimurium, and O157: H7 at MIC range 16-18 g L. Extract affected the different phases of bacterial growth. In addition, application of Extract (25 g L) as a sanitizer was effective to reduce the populations of all bacteria inoculated in lettuce (0.859-1.884 log reduction) and spinach (0.843-2.605 log reduction). This study emphasizes the potential of grape processing byproducts as an emergent and attractive source of bioactive compounds with antioxidant properties and antimicrobial activity against important foodborne pathogens. The study demonstrated that stem extract could be used to control the presence of human pathogenic bacteria in fresh leafy vegetables.

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The objective of the present study is to evaluate the effect of individual and combined coatings of chitosan (0.008 g·mL−1) and carnauba wax (0.1 g·mL−1) with oregano essential oil (OEO, 0.08 g·mL−1) to reduce dehydration and microbial decay of fresh cucumbers stored at 10 °C. Chitosan-OEO-wax films showed the lowest water vapor transmission rate (0.141 g·m−2·h−1), compared to single chitosan films (0.257 g·m−2·h−1). While chitosan-OEO films completely inhibited the in vitro growth of Alternaria alternata and reduced the growth of Salmonella Typhimurium, Escherichia coli O157:H7, mesophilic bacteria, and fungi isolated from decayed cucumbers. Besides, the infrared analysis of chitosan-OEO-wax films showed shifts in O–H and N–H absorption bands, indicating possible hydrogen bonding between the components. Wax and wax-OEO were the most effective coatings to prevent weight loss in cucumbers during 15 days of storage at 10 °C, while the most effective antimicrobial treatments were chitosan and chitosan-OEO. Therefore, these results showed that carnauba wax and carnauba wax-OEO coatings were the most effective in weight loss, whereas chitosan and chitosan-OEO were the most effective to reduce the microbial load of the treated fresh cucumber.