ABSTRACT
Emergence of drug-resistant strains has demanded for alternative means of combating fungal infections. Oils of Carum copticum and Thymus vulgaris have long been used in ethnomedicine for ailments of various fungal infections. Since their activity has not been reported in particular against drug-resistant fungi, this study was aimed to evaluate the effects of oils of C. copticum and T. vulgaris on the growth and virulence of drug-resistant strains of Aspergillus spp. and Trichophyton rubrum. The gas chromatography-mass spectrometry analysis revealed thymol constituting 44.71% and 22.82% of T. vulgaris and C. copticum, respectively. Inhibition of mycelial growth by essential oils was recorded in the order of thymol > T. vulgaris > C. copticum against the tested strains. RBC lysis assay showed no tested oils to be toxic even up to concentration two folds higher than their respective MFCs. Thymol exhibited highest synergy in combination with fluconazole against Aspergillus fumigatus MTCC2550 (FICI value 0.187) and T. rubrum IOA9 (0.156) as determined by checkerboard method. Thymol and T. vulgaris essential oil were equally effective against both the macro and arthroconidia growth (MIC 72 µg/mL). A > 80% reduction in elastase activity was recorded for A. fumigatus MTCC2550 by C. copticum, T. vulgaris oils and thymol. The effectiveness of these oils against arthroconidia and synergistic interaction of thymol and T. vulgaris with fluconazole can be exploited to potentiate the antifungal effects of fluconazole against drug-resistant strains of T. rubrum and Aspergillus spp.
Subject(s)
Antifungal Agents/pharmacology , Aspergillus fumigatus/drug effects , Carum/chemistry , Plant Oils/pharmacology , Thymus Plant/chemistry , Trichophyton/drug effects , Antifungal Agents/isolation & purification , Antifungal Agents/toxicity , Aspergillus fumigatus/growth & development , Aspergillus fumigatus/physiology , Drug Synergism , Erythrocytes/drug effects , Fluconazole/pharmacology , Gas Chromatography-Mass Spectrometry , Pancreatic Elastase/antagonists & inhibitors , Plant Oils/chemistry , Plant Oils/isolation & purification , Plant Oils/toxicity , Spores, Fungal/drug effects , Spores, Fungal/growth & development , Thymol/analysis , Trichophyton/physiology , Virulence/drug effectsABSTRACT
The goals of this study were to evaluate the effectiveness of Cuminum cyminum, Ziziphora clinopodioides and Nigella sativa essential oils to inhibit the growth of Aspergillus fumigatus and A. flavus and to evoke ultrastructural changes. The fungi were cultured into RPMI 1640 media in the presence of oils at concentrations of 8, 6, 5, 4, 3, 2, 1.5, 1.25, 1, 0.75 and 0.5 mg/ml in broth microdilution and 2, 1.5, 1 and 0.5 mg/ml in broth macrodilution methods with shaking for 48 h at 28ºC. Conidial and mycelial samples exposed to 0.25, 0.5, 1, 1.5 and 2 mg essential oils/ml for 5 days in 2 percent yeast extract granulated plus 15 percent Saccharose media were processed for transmission electron microscopy (TEM). Based on broth dilution methods, C. cyminum and to a lesser extent Z. clinopodioides oils exhibited the strongest activity against A. fumigatus and A. flavus with MIC90 ranging from 0.25 to 1.5 mg/ml, while the oil from N. sativa exhibited relatively moderate activity against two above fungi with MIC90 ranging from 1.5 to 2 mg/ml. The main changes observed by TEM were in the cell wall, plasma membrane and membranous organelles; in particular, in the nuclei and mitochondria. These modifications in fungal structure were associated with the interference of the essential oils with the enzymes responsible for cell wall synthesis, which disturbed normal growth. Moreover, the essential oils caused high vacuolation of the cytoplasm, detachment of fibrillar layer of cell wall, plasma membrane disruption and disorganization of the nuclear and mitochondrial structures. Aspergillus fumigatus and A. flavus growth inhibition induced by these oils were found to be well-correlated with subsequent morphological changes of the fungi exposed to different fungistatic concentrations of the oils. Our results show the anti-Aspergillus activities of C. cyminum, Z. clinopodioides and N. sativa essential oils, which strengthens the potential use of these substances as anti-mould in the future.
Subject(s)
Aspergillus flavus/growth & development , Aspergillus fumigatus/growth & development , Cell Wall , Culture Media , Cuminum/growth & development , Enzyme Activation , Oils, Volatile/analysis , Efficacy , Methods , Microscopy, Electron , Plant Preparations , MethodsABSTRACT
A case of invasive multiple paranasal sinus aspergillosis with bony involvement is reported. A young immunocompetent lady presented with bilateral nasal obstruction due to polyps. Radiologically and histopathologically a fungal cause was kept a possibility, and the diagnosis of Aspegillus fumigatus was established by demonstration of acute angle branching septate hyphae on direct wet mount and repeated isolation in culture. Patient responded favourably to surgical excision of polyps and oral itraconazole post operatively.