Chemical composition and antifungal activity of essential oil from Eucalyptus smithii against dermatophytes

ABSTRACT INTRODUCTION: In this study, we evaluated the chemical composition of a commercial sample of essential oil from Eucalyptus smithii R.T. Baker and its antifungal activity against Microsporum canis ATCC 32903, Microsporum gypseum ATCC 14683, Trichophyton mentagrophytes ATCC 9533, T. mentagrophytes ATCC 11480, T. mentagrophytes ATCC 11481, and Trichophyton rubrum CCT 5507. METHODS: Morphological changes in these fungi after treatment with the oil were determined by scanning electron microscopy (SEM). The antifungal activity of the oil was determined on the basis of minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) values. RESULTS: The compound 1,8-cineole was found to be the predominant component (72.2%) of the essential oil. The MIC values of the oil ranged from 62.5μg·mL−1 to >1,000μg·mL−1, and the MFC values of the oil ranged from 125μg·mL−1 to >1,000μg·mL−1. SEM analysis showed physical damage and morphological alterations in the fungi exposed to this oil. CONCLUSIONS: We demonstrated the potential of Eucalyptus smithii essential oil as a natural therapeutic agent for the treatment of dermatophytosis

Applied Research Note: Pulsed-field gel electrophoresis and antimicrobial resistance profiles of Campylobacter jejuni isolated from Brazilian broiler farms

SUMMARY: We studied the on-farm variety of thermotolerant Campylobacter strains isolated from field samples received over a 12-mo period from four broiler-producing companies in southern Brazil. In total, 515 of 807 (63.8%) of analyzed samples were found to be Campylobacter-positive. Campylobacter jejuni and C. coli were detected; the first one being more frequently isolated (98.2%). The highest antimicrobial resistance levels in a subset of 80 C. jejuni strains were found against enrofloxacin (89.5%) and ciprofloxacin (83.3%). Most of the 28 DNA macrorestriction profiles identified in C. jejuni were unique to each sampled broiler company. Genetically related C. jejuni populations were detected on different broiler farms integrated to the same company on different sampling occasions. Undistinguished strains were found in the indoor environment and in broilers on the same farm. The finding of recurrent strains on integrated farms suggests that particular factors or management practices may play a role in the dispersion or carry-over of C. jejuni in the studied broiler companies