EFFECTS OF COMMERCIAL ANTIFUNGALS AND PLANT ESSENTIAL OILS ON NOSOCOMIAL FUNGI ISOLATED FROM SELECTED HOSPITALS IN AKURE METROPOLIS

Abstract

This research evaluated the effects of commercial antifungals and plant essential oils on nosocomial fungi isolated from selected hospitals in Akure metropolis. Samples were collected from fomites in the hospital environment. Fungi were isolated and identified using cultural and microscopy methods. A total of three hundred and three (303) samples were collected, 447 fungal isolates were obtained, 241 (54%) and 206 (46%) from the University of Medical Sciences Teaching Hospital (UNIMEDTH) Akure and FUTA Health Centre respectively. A total of eleven (11) fungal genera with many species were isolated. Fusarium oxysporum and Candida krusei had the highest occurrence rate from UNIMEDTH and FUTA Health Centre with (14.11 %) and (16.82 %) respectively. The results of the antifungal sensitivity test revealed significant differences (p≤0.05) in the sensitivity patterns. Ketoconazole was identified to be the most potent in this study, showing the highest zone of inhibition (25.03 mm) in Aspergillus flavus. The effectiveness of the commercial antifungal agent is in increasing order from Griseofulvin < Clotrimazole < Fluconazole < Ketoconazole. The higher the concentration of the antifungal agents, the higher the zones of inhibition. Most of the fungal isolates were resistant to only Griseofulvin, except for Fusarium oxysporum, Fusarium solani, Aspergillus fumigatus, Alternaria alternata which were all resistant to Griseofulvin and Clotrimazole. All the four (4) isolates screened using disc diffusion method with the essential oils from Khaya senegalensis and Tithonia diversifolia were sensitive. Khaya senegalensis showed higher zones of inhibition against the tested isolates at different concentrations. The essential oil of Khaya senegalensis showed the lowest MIC value of 4 mg/ml and MFC value of 3 mg/ml against Alternaria alternata which shows the highest activity of all the other fungal isolates. The Fourier vii Transform Infrared (FTIR) spectroscopy and the peaks revealed the functional groups of the fractions responsible for antifungal activity. Gas Chromatography Mass Spectrometry (GCMS) analysis of the biologically active compounds in the essential oils of K. senegalensis and T. diversifolia also showed the presence of caryophyllene oxide, isocaryophyllene, α- Pinene and Borneol. Thus, the plant essential oils performed better than the standard antifungal agents used in this study.