Plant Extracts: Antimicrobial Properties, Mechanisms of Action and Applications

Abstract

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.

An Eco-friendly Approach to ZnO NP Synthesis Using Citrus reticulata Blanco Peel/Extract: Characterization and Antibacterial and Photocatalytic Activity

“…aureus, suggesting that they are more efficient against this Gram-positive species. Gram-positive bacteria are generally more sensitive to naturally derived compounds or plant extracts due to the lack of an outer membrane as the additional layer of protection . This supports previous reports using ZnO nanoparticles that also showed a much stronger antibacterial effect on Gram-positive bacteria than on Gram-negative ones …”

“…Grampositive bacteria are generally more sensitive to naturally derived compounds or plant extracts due to the lack of an outer membrane as the additional layer of protection. 52 This supports previous reports using ZnO nanoparticles that also showed a much stronger antibacterial effect on Gram-positive bacteria than on Gram-negative ones. 53 The generation of reactive oxygen species (ROS) is the most studied and widely accepted mechanism for the antimicrobial activities of ZnO under both UV−visible and dark conditions.…”

Deciphering the antimicrobial, antibiofilm and membrane stabilizing synergism of Mikania scandens (L.) Willd. leaves and stems substantiation through in vitro and in silico studies

“…Notwithstanding that bacterial structural alterations of efflux and influx system for resistance documented in S. aureus, P. aeruginosa and A. baumannii [ 55 , 56 ]. Importantly, this same ethyl acetate MSL extracts disclosed almost considerable eptitude against both gram positive and negative bacteria opposed to conventional plant extracts resistance towards gram-negative bacteria due to hydrophilic cover over peptidoglycan which accountable for easy accessible of plant extractives in gram positive bacteria [57] .…”

Antimicrobial activity of dietary supplements based on bacterial lysate of Lactobacillus rhamnosus DV

“…It is widely accepted that bioactive compounds extracted from plants significantly impact human health. As a result, it is crucial to comprehend the antimicrobial effectiveness and mode of operation of these plant-derived bioactive compounds ( Kha and Le, 2021 ). Plants with medicinal properties contain various phytochemicals like flavonoids, alkaloids, tannins, and terpenoids.…”