The role of structure and molecular properties of terpenoids in determining their antimicrobial activity

Abstract

The minimum inhibitory concentrations (MIC) of 60 terpenoids against Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus and Candida albicans have been determined. Hierarchical cluster analysis was used to group the compounds into five groups according to their activity patterns against the four microorganisms. K‐Means cluster analysis was then used to confirm these groupings and to show the differences in the activity patterns of the groups. Ten molecular properties of the terpenoids, either calculated via molecular modelling or determined by direct measurement, were then used as variables in a forward stepwise discriminant analysis to identify which variables discriminated between groups. Low water solubility of Group IV compounds, mainly hydrocarbons and acetates, was found to be associated with their relative inactivity. The remaining groups, all containing oxygenated terpenoids, showed characteristic but distinct activity patterns towards the four test organisms. Hydrogen bonding parameters were found to be associated with antimicrobial activity in all cases. Activity against Gram‐negative E. coli and P. aeruginosa was associated with a combination of a hydrogen bonding and size parameters. This was not found to be the case for the Gram‐positive S. aureus or the yeast C. albicans. Copyright © 1999 John Wiley & Sons, Ltd.

Composition chimique et activités antibactériennes, antifongiques et antioxydante de l'huile essentielle dePelargonium asperumEhrh.exWilde des Comores

“…D'une façon générale, les activités antibactériennes et antifongiques de l'huile de géranium Bourbon peuvent être attribuées principalement aux alcools terpéniques (citronellol, géraniol, linalol) qui représentent environ 50,07% des constituants de cette huile. En effet, les terpènes oxygénés sont des agents antimicrobiens très actifs (Gueldener et al, 1985 ;Faid et al, 1996 ;Griffin et al, 1999 ;Dorman & Deans, 2000 ;Kamran et al, 2001 ;Satrani et al, 2006). En outre, plusieurs études ont montré qu'en raison de la complexité chimique des huiles essentielles une activité antimicrobienne beaucoup plus prononcée que celle prévisible pour les composés majoritaires peut être due à la présence d'interactions synergiques entre composés (Franchomme, 1981 ;Kurita & Koik, 1982 ;Gueldener et al, 1985 ;Inouy et al, 2000 ;Burt, 2004 ;vinda-Martos et al, 2008).…”

Isolation and screening of d-limonene-resistant microorganisms

“…activity, but it is an essential characteristic to a biotransforming agent. Generally, the minimum inhibitory concentration (MIC) of limonene against some bacteria and yeasts are lower than 2% (14), although some fungi, e.g. Penicillium digitatum, presents only a small reduction on its bioconversion activity in concentrations of 4-8% limonene (27) and some bacteria, e.g.…”

Carvacrol and thymol components inhibiting Pseudomonas aeruginosa adherence and biofilm formation

“…In the presence of carvacrol and thymol (2 MIC), the mean biofilm formation values were equal to 91±0.8 and 86±2.1% for P. aeruginosa (ATCC 27853), and 62±1.2% and 54±5.9% for P. aeruginosa (CIP A22), and 90±2.5% and 70±4.3 for P. aeruginosa (IL5), respectively. Carvacrol and thymol have a log Po/w of 3.64 and 3.30, respectively (Griffin et al, 1999;Ultee et al, 2002). Weber and de Bont (1996) reported that compounds with a log Po/w value higher than 3 are highly potent on disturbing cell membrane.…”