Essential Oils from Fruit and Vegetables, Aromatic Herbs, and Spices: Composition, Antioxidant, and Antimicrobial Activities

Abstract

The use of essential oils (EOs) in the food industry is a popular research topic, as they have antioxidant and antimicrobial activity and could be used as ingredients directly in food or as bioactive component in food coating and food packaging. Thus, the study of their antioxidant and antimicrobial activity is a crucial step to evaluate their use in food packaging/coating. In this work, we evaluate the antioxidant and antimicrobial activities of 13 EOs from herbs, spices, fruits, and vegetables. Briefly, the EOs from aromatic herbs and spices showed the highest antioxidant and antimicrobial activity. Fennel essential oil reported the lowest antioxidant activity, however it showed very good antimicrobial activity against Botrytis cinerea, one of the post-harvest pathogen microorganisms in fruits and vegetables.

In the field of food preservation, encapsulated Essential Oils (EOs) could be the best non-toxic and eco-friendly tool for food preservative applications substituting the chemicals ones that have several disadvantages for the environment and health. Thirteen commercial EOs from plants, fruits, and vegetables were characterized by GC-MS. The antioxidant activity was measured by DPPH and ABTS techniques. Antimicrobial activity was assessed by agar well-diffusion method and the Minimum Inhibitory Concentration (MIC) by agar dilution method against six bacteria, Candida albicans, and Botrytis cinerea. All the EOs tested have demonstrated antioxidant activity in the range of IC50 0.01–105.32 mg/mL. Between them, cinnamon EOs were the best, followed by oregano and thyme EOs. Fennel EO showed the lowest radical scavenging. MIC values ranged from 0.14 to 9 mg/mL. C. cassia, thyme, and oregano EOs were the most effective against the bacterial species tested, and the yeast C. albicans. On the contrary, citric fruit EOs showed low or no inhibition against most bacterial strains. The percentages of inhibition of mycelia growth of B. cinerea ranged from 3.4 to 98.5%. Thyme, oregano, mint, and fennel EOs showed the highest inhibition.