Proton pumping ATPase mediated fungicidal activity of two essential oil components

Abstract

This work evaluates the antifungal activity of two essential oil components against 28 clinical isolates (17 sensitive, 11 resistant) and 3 standard laboratory strains of Candida. Growth of the organisms was significantly effected in both solid and liquid media at different test compound concentrations. The minimum inhibitory concentrations (MICs) of Isoeugenol (compound 1) against 31 strains of Candida ranged 100-250 μg/ml and those of o -methoxy cinnamaldehyde (compound 2) ranged 200-500 μg/ml, respectively. Insight studies to mechanism suggested that these compounds exert antifungal activity by targeting H(+)-ATPase located in the membranes of pathogenic Candida species. At their respective MIC(90) average inhibition of H(+)-efflux for standard, clinical and resistant isolates caused by compound 1 and compound 2 was 70%, 74%, 82% and 42%, 42% and 43%. Respective inhibition of H(+)-efflux by fluconazole (5 μg/ml) was 94%, 92% and 10%. Inhibition of H(+)-ATPase leads to intracellular acidification and cell death. SEM analysis of Candida cells showed cell membrane breakage and alterations in morphology. Haemolytic activity on human erythrocytes was studied to exclude the possibility of further associated cytotoxicity.

An inclusion complex of eugenol into β-cyclodextrin: Preparation, and physicochemical and antifungal characterization

“…Bhatia et al (2012) reported the fungicidal activity of two essential oil components against Candida species through H + / ATPase-mediated inhibition. In addition, the tolerance of yeast to EG was evaluated by studying the calcium ion influx via a plasma membrane calcium channel (Roberts, McAinsh, Cantopher, & Sandison, 2014).…”

Antifungal Properties of Two Volatile Organic Compounds on Barley Pathogens and Introduction to Their Mechanism of Action

“…In order to promote the use of methyl prop-2-enoate and methyl propanoate in agriculture, the development of cost-effective preparations is highly required. Alginate beads were recently used as vectors to ensure a slow diffusion of volatile molecules in the soil to fight against parasitoids and aphid predators [12,29]. The same strategy could be adopted to coat the antifungal molecules methyl prop-2-enoate and methyl propanoate and ensure their diffusion in the soil.…”

Isoeugenol has a non-disruptive detergent-like mechanism of action

“…In spite of isoeugenol's promising antibacterial activity, no studies have yet been performed to identify how isoeugenol affects bacteria at the molecular scale. One study evaluated isoeugenol's mode of antifungal action against Candida spp., and suggested that isoeugenol inhibits H + -ATPase, which triggers intracellular acidification and cell membrane breakages (Bhatia et al, 2012 ). Focusing on the mode of action of the structurally closely related compound eugenol, studies indicate that the cell structure becomes distorted due to a non-specific cytoplasmic membrane permeabilization effect together with the ability of eugenol to inhibit enzyme or protein functionality (Thoroski et al, 1989 ; Wendakoon and Morihiko, 1995 ; Gill and Holley, 2006b , a ; Hemaiswarya and Doble, 2009 ).…”