ABSTRACT
The dengue virus is transmitted by Aedes aegypti. Several plants are used to control this mosquito. In the present study the chemical composition of the essential oils of Ruta chalepensis, Zanthoxylum fagara and Thymus vulgaris were analyzed, and their activities against larvae of two A. aegypti populations were evaluated. The major compounds found in T vulgaris were thymol and o-cymene at 39.8% and 30.5%, respectively, with the major components being oxygenated monoterpenes and monoterpene hydrocarbons at 55.5% and 40.4%, respectively. For Z. fagara, the major compounds were sylvestrene and E-caryophyllene at 25.3% and 23.6%, respectively, with the major components being sesquiterpene and monoterpene hydrocarbons at 51.1% and 37.5%, respectively. Ketones were the predominant group of compounds found in R. chalepensis, with the major components being 2-undecanone and 2- nonanona at 43.7% and 35.4%, respectively. Essential oils from T vulgaris, Z. fagara and R. chalepensis showed activity against larvae of the A. aegypti New Orleans strain, producing median lethal concentrations [LC[50]] of 2.14, 27.57 and 2.69.Mug/mL, respectively, at 24 h. LC[50] values produced against larvae of a local A. aegypti population in Nuevo Leon, Mexico, were 25.37, 60.42 and 20.13Mug/mL, respectively, at 24 h
ABSTRACT
There have been no reports of antifungal activity and composition of extracts from Thymus vulgaris, Rosmarinus officinalis or Origanum majorana from northeastern Mexico. Antifungal activity of these oils against Trichophyton rubrum, Trichophyton tonsurans, Trichophyton mentagrophytes, Microsporum gypseum, Microsporum canis and Epidermophyton floccosum was measured by diffusion assay. Additionally, antibacterial and antioxidant activities were evaluated. Antibacterial activity against Staphylococcus aureus and Streptococcus pyogenes was examined by microdilution. Antioxidant activity was assessed by 2, 2-difenil-1-picrilhidracil reduction test. The plant oils were characterized by both GC/MS and GC/FID. Oils of T. vulgaris and O. majorana showed growth inhibition activity against dermatophytes, especially T. vulgaris oil, which completely inhibited growth of all tested dermatophytes. The oils also showed bioactivity against bacteria, with minimum inhibitory concentration [MIC] values between 62.5 and 500 micro g/mL. The antioxidant activity of the oils was low, with effective concentration [EC50] values >250 micro g/mL. The major components in the oils were as follows: T. vulgaris, o-cymene, gamma-terpinene, thymol and carvacrol; R. officinalis, terpinen-4-ol and 1,8-cineole; O. majorana, terpinen-4-ol and thymol