Header

UZH-Logo

Maintenance Infos

Additive antimicrobial [corrected] effects of the active components of the essential oil of Thymus vulgaris--chemotype carvacrol


Iten, F; Saller, R; Abel, G; Reichling, J (2009). Additive antimicrobial [corrected] effects of the active components of the essential oil of Thymus vulgaris--chemotype carvacrol. Planta Medica, 75(11):1231-1236.

Abstract

Herbal remedies are multicomponent mixtures by their nature as well as by pharmaceutical definition. Being a multicomponent mixture is not only a crucial property of herbal remedies, it also represents a precondition for interactions such as synergism or antagonism. Until now, only a few phytomedicines are accurately described concerning the interactions of their active components. The aim of this study was to search for interactions within such a naturally given multi-component mixture and to discuss the pharmaceutical and clinical impacts. The thyme oil chosen for the examination belongs to the essential oils with the most pronounced antimicrobial activity. Antibiotic activity of thyme oil and single active components were tested against six different strains of microorganisms. The checkerboard assay was used to search for interactions. The time-kill assay was used to verify the observed effects and to get information about the temporal resolution of the antimicrobial activity. The degree of the detected interactions corresponded with the demarcating FICI measure of 0.5, which separates the additive from the over-additive (synergistic) effects. Therefore, the observed effect was called a "borderline case of synergism" or, respectively, "partial synergism". Partial synergism was observed only in the presence of Klebsiella pneumoniae. Additive antimicrobial activity was observed for the combination of the two monosubstances carvacrol plus linalool and thymol plus linalool as well as with the combination of the two essential oils of the carvacrol and linalool chemotypes. An increase of the carvacrol oil concentration from one to two times the MIC resulted in a considerable acceleration of the kill-rate. Thyme oil is composed of several different components that show antimicrobial activity (at least: carvacrol, thymol and linalool). The antimicrobial activity of thyme oil is partly based on additive effects, which might especially enhance the rapidity of the antimicrobial action. In addition, a mixture of several active ingredients that varies in its composition from year to year and from lot to lot as is the case with herbal remedies may be more stable concerning the antimicrobial activity than mixtures containing just a single active component.

Abstract

Herbal remedies are multicomponent mixtures by their nature as well as by pharmaceutical definition. Being a multicomponent mixture is not only a crucial property of herbal remedies, it also represents a precondition for interactions such as synergism or antagonism. Until now, only a few phytomedicines are accurately described concerning the interactions of their active components. The aim of this study was to search for interactions within such a naturally given multi-component mixture and to discuss the pharmaceutical and clinical impacts. The thyme oil chosen for the examination belongs to the essential oils with the most pronounced antimicrobial activity. Antibiotic activity of thyme oil and single active components were tested against six different strains of microorganisms. The checkerboard assay was used to search for interactions. The time-kill assay was used to verify the observed effects and to get information about the temporal resolution of the antimicrobial activity. The degree of the detected interactions corresponded with the demarcating FICI measure of 0.5, which separates the additive from the over-additive (synergistic) effects. Therefore, the observed effect was called a "borderline case of synergism" or, respectively, "partial synergism". Partial synergism was observed only in the presence of Klebsiella pneumoniae. Additive antimicrobial activity was observed for the combination of the two monosubstances carvacrol plus linalool and thymol plus linalool as well as with the combination of the two essential oils of the carvacrol and linalool chemotypes. An increase of the carvacrol oil concentration from one to two times the MIC resulted in a considerable acceleration of the kill-rate. Thyme oil is composed of several different components that show antimicrobial activity (at least: carvacrol, thymol and linalool). The antimicrobial activity of thyme oil is partly based on additive effects, which might especially enhance the rapidity of the antimicrobial action. In addition, a mixture of several active ingredients that varies in its composition from year to year and from lot to lot as is the case with herbal remedies may be more stable concerning the antimicrobial activity than mixtures containing just a single active component.

Statistics

Citations

Dimensions.ai Metrics
41 citations in Web of Science®
44 citations in Scopus®
Google Scholar™

Altmetrics

Downloads

339 downloads since deposited on 03 Jun 2009
38 downloads since 12 months
Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:04 Faculty of Medicine > University Hospital Zurich > Institute of Complementary Medicine
Dewey Decimal Classification:610 Medicine & health
Language:English
Date:2009
Deposited On:03 Jun 2009 08:35
Last Modified:17 Feb 2018 22:52
Publisher:Thieme
ISSN:0032-0943
Additional Information:Copyright: Georg Thieme Verlag Erratum in: Planta Med. 2009 Sep;75(11):1236
OA Status:Green
Publisher DOI:https://doi.org/10.1055/s-0029-1185541
PubMed ID:19347798

Download

Download PDF  'Additive antimicrobial [corrected] effects of the active components of the essential oil of Thymus vulgaris--chemotype carvacrol'.
Preview
Content: Accepted Version
Filetype: PDF
Size: 1MB
View at publisher