Insights into the Relationships Between Herbicide Activities, Molecular Structure and Membrane Interaction of Cinnamon and Citronella Essential Oils Components

Abstract

Since the 50’s, the massive and “environmental naïve” use of synthetic chemistry has revolutionized the farming community facing the dramatic growth of demography. However, nowadays, the controversy grows regarding the long-term harmful effects of these products on human health and the environment. In this context, the use of essential oils (EOs) could be an alternative to chemical products and a better understanding of their mode of biological action for new and optimal applications is of importance. Indeed, if the biocidal effects of some EOs or their components have been at least partly elucidated at the molecular level, very little is currently known regarding their mechanism of action as herbicides at the molecular level. Here, we showed that cinnamon and Java citronella essential oils and some of their main components, i.e.,, cinnamaldehyde (CIN), citronellal (CitA), and citronellol (CitO) could act as efficient herbicides when spread on A. thaliana leaves. The individual EO molecules are small amphiphiles, allowing for them to cross the mesh of cell wall and directly interact with the plant plasma membrane (PPM), which is one of the potential cellular targets of EOs. Hence, we investigated and characterized their interaction with biomimetic PPM while using an integrative biophysical approach. If CitO and CitA, maintaining a similar chemical structure, are able to interact with the model membranes without permeabilizing effect, CIN belonging to the phenylpropanoid family, is not. We suggested that different mechanisms of action for the two types of molecules can occur: while the monoterpenes could disturb the lipid organization and/or domain formation, the phenylpropanoid CIN could interact with membrane receptors.

Thymol Chemotype Origanum vulgare L. Essential Oil as a Potential Selective Bio-Based Herbicide on Monocot Plant Species

“…hirtum EO against monocot plant species (Echinochloa crus-galli and Oryza sativa) compared to the other tested plant species; both monocot species were less sensitive [36]. The molecular structure of each component can be responsible for the specific MOA as was previously mentioned [9]. Developing a selective herbicide, even if some data are promising, is difficult in the moment.…”

“…Essential oils (EOs) are complex mixtures of mostly terpenoids as plant secondary metabolites. It has been recognized that various EO components act as multi-target molecules exerting several MOAs in the recipient-organism [7,8], that can be beneficial compared to conventional herbicides which induce resistance [9]. Single EO molecules are able to cross the cell wall and directly interact with the plant plasma membrane, which is one of the potential cellular targets of EOs.…”

“…Single EO molecules are able to cross the cell wall and directly interact with the plant plasma membrane, which is one of the potential cellular targets of EOs. It is known that while monoterpenes disturb the lipid organization and/or domain formation, phenylpropanoid could interact with membrane receptors [9].…”

Phytotoxicity of Essential Oils: Opportunities and Constraints for the Development of Biopesticides. A Review

“…Similar work on model bilayer interactions with related monoterpenes, including limonene, perillyl alcohol and aldehyde, demonstrates the diffusion across the membrane and an ordering effect on the lipid bilayer [34]. More recently, novel molecular techniques of dynamic interaction were applied to study the interaction between citronellal (monoterpene), citronellol (monoterpene) and cinnamaldehyde (phenylpropanoids) with a biomimetic membrane [35]. Briefly, the in silico insertion model predicted different behaviors between the two classes (monoterpenes and phenylpropanoids).…”

Seasonal Effect on the Chemical Composition, Insecticidal Properties and Other Biological Activities of Zanthoxylum leprieurii Guill. & Perr. Essential Oils

“…Essential oil dilutions (10,14,18,22,26 and 30 µL/mL) were prepared in acetone. Talisma UL (Biosix, Hermalle-sous-Huy, Belgium), a classical chemical insecticide used for the protection of stored grains against insects, was also used at the same concentrations.…”