Plant Extracts: Antimicrobial Properties, Mechanisms of Action and Applications

It is generally agreed that bioactive compounds derived from plants play an important role in human health. Therefore, it is desirable to understand antimicrobial properties and mechanism of action of bioactive compounds from plants. This chapter presents a general overview of the plant extract sources, chemical structures, and antimicrobial properties. Particularly, understanding of the chemical structures of bioactives is of importance for more in-depth understanding of the mechanisms of the antimicrobial actions. The evaluation techniques for antimicrobial activity of the bioactive compounds, broadly classified as diffusion and dilution methods, are also presented in terms of principles, applications, affecting factors, advantages, and drawbacks. Furthermore, applications of plant bioactive compounds as antimicrobial preservatives in foods are also discussed.