The hydroxyl moiety on carbon one (C1) in the monoterpene nucleus of thymol is indispensable for anti-bacterial effect of thymol.
Biological sciences
E. coli
Essential oils
Ester-substitution
Ether-substitution
Ethnopharmacology
Food toxicology
Health sciences
Monoterpenes
P. aeruginosa
Pharmacology
S. aureus
Structure activity relation
Thymol
Toxicology
Journal
Heliyon
ISSN: 2405-8440
Titre abrégé: Heliyon
Pays: England
ID NLM: 101672560
Informations de publication
Date de publication:
Mar 2020
Mar 2020
Historique:
received:
05
01
2020
revised:
05
02
2020
accepted:
21
02
2020
entrez:
21
3
2020
pubmed:
21
3
2020
medline:
21
3
2020
Statut:
epublish
Résumé
Thymol, a natural monoterpene phenol is not only relevant clinically as an anti-microbial, anti-oxidant and anti-inflammatory agent but also holds the prospect as a natural template for pharmaceutical semi-synthesis of therapeutic agents. It is a major component of essential oils from many plants. Evidence abound linking overall bioactivity of thymol to its monoterpene nucleus, specifically, the hydroxyl (-OH) substituent on carbon number one (C1) on the monoterpene nucleus. Other studies have posited that the overall bioactivity of thymol is not substantially altered by chemical modification of - OH on the C1 of the monoterpene nucleus. In view of this, it is still unclear as to whether removal or modification of the -OH on C1 of the monoterpene nucleus relates generally or context-dependently to bioactivity of thymol. The present study investigated anti-bacterial effects of ester-and-ether substituted derivatives of thymol on twelve ester-and-ether substituted derivatives of thymol (6TM1s and 6TM2s) were synthesized and characterized by using HPLC, Mass spectrometry, and IR techniques. Anti-bacterial activity of the 12 thymol derivatives was evaluated using broth macrodilution and turbidimetric methods against pure clinical isolates ( Thymol produced broad-spectrum growth inhibition on all isolates. At equimolar concentrations, thymol and reference drugs produced concentration-dependent growth inhibition against the isolates ( Thymol has demonstrated broad-spectrum anti-bacterial effects attributable to the hydroxyl moiety on C1 of the monoterpene nucleus. Structural modification of the hydroxyl moiety on C1 of the monoterpene nucleus of thymol with either ether-or-ester substitutions yielded no significant anti-bacterial effects.
Sections du résumé
BACKGROUND
BACKGROUND
Thymol, a natural monoterpene phenol is not only relevant clinically as an anti-microbial, anti-oxidant and anti-inflammatory agent but also holds the prospect as a natural template for pharmaceutical semi-synthesis of therapeutic agents. It is a major component of essential oils from many plants. Evidence abound linking overall bioactivity of thymol to its monoterpene nucleus, specifically, the hydroxyl (-OH) substituent on carbon number one (C1) on the monoterpene nucleus. Other studies have posited that the overall bioactivity of thymol is not substantially altered by chemical modification of - OH on the C1 of the monoterpene nucleus. In view of this, it is still unclear as to whether removal or modification of the -OH on C1 of the monoterpene nucleus relates generally or context-dependently to bioactivity of thymol.
OBJECTIVE
OBJECTIVE
The present study investigated anti-bacterial effects of ester-and-ether substituted derivatives of thymol on
MATERIALS AND METHODS
METHODS
twelve ester-and-ether substituted derivatives of thymol (6TM1s and 6TM2s) were synthesized and characterized by using HPLC, Mass spectrometry, and IR techniques. Anti-bacterial activity of the 12 thymol derivatives was evaluated using broth macrodilution and turbidimetric methods against pure clinical isolates (
RESULTS
RESULTS
Thymol produced broad-spectrum growth inhibition on all isolates. At equimolar concentrations, thymol and reference drugs produced concentration-dependent growth inhibition against the isolates (
CONCLUSION
CONCLUSIONS
Thymol has demonstrated broad-spectrum anti-bacterial effects attributable to the hydroxyl moiety on C1 of the monoterpene nucleus. Structural modification of the hydroxyl moiety on C1 of the monoterpene nucleus of thymol with either ether-or-ester substitutions yielded no significant anti-bacterial effects.
Identifiants
pubmed: 32195386
doi: 10.1016/j.heliyon.2020.e03492
pii: S2405-8440(20)30337-6
pii: e03492
pmc: PMC7078539
doi:
Types de publication
Journal Article
Langues
eng
Pagination
e03492Informations de copyright
© 2020 The Author(s).
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