Marzieh Halvaeezadeh, Gholam Ali Jalaee, Mahnaz Fatahinia, Ali Zarei Mahmoudabadi
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Abstract
Background and objectives: The ability of Aspergillus species to produce various extracellular enzymes has a pathogenic role in humans. These enzymes not only play a role in metabolism but also act as virulence factors. The secretion of hydrolytic enzymes facilitates tissue invasion and is considered a virulence factor for several fungi. The current study aimed to compare the enzymatic activity of A. flavus section Flavi isolated from otomycosis and environmental samples.
Materials and methods: In the present study, eighty-one isolates of A. flavus including 41 clinical strains from otomycosis and 40 environmental isolates were identified using the calmodulin gene. The enzymatic activity of the isolates was assessed using standard culture media.
Results: All isolates exhibited phospholipase and urease activity. Esterase and hemolysin activity in otomycosis isolates were higher than in environmental isolates (88% > 62%), (98% > 72%). High levels of both extracellular and intracellular catalase activity were detected among otomycosis isolates.
Conclusion: All isolates were phenotypically identified as Aspergillus section Flavi and then characterized using the calmodulin gene. The mean activity of intracellular catalase enzymes (1.29) in both groups was higher than the mean activity of extracellular catalase enzymes (0.85). Additionally, the esterase (88%) and hemolysin (98%) activity of the clinical isolates was higher than that of the environmental isolates (esterase 62%, hemolysin 72%). All isolates exhibited phospholipase and urease activity.
期刊介绍：
The Iranian Journal of Microbiology (IJM) is an international, multi-disciplinary, peer-reviewed journal that provides rapid publication of the most advanced scientific research in the areas of basic and applied research on bacteria and other micro-organisms, including bacteria, viruses, yeasts, fungi, microalgae, and protozoa concerning the development of tools for diagnosis and disease control, epidemiology, antimicrobial agents, clinical microbiology, immunology, Genetics, Genomics and Molecular Biology. Contributions may be in the form of original research papers, review articles, short communications, case reports, technical reports, and letters to the Editor. Research findings must be novel and the original data must be available for review by the Editors, if necessary. Studies that are preliminary, of weak originality or merely descriptive as well as negative results are not appropriate for the journal. Papers considered for publication must be unpublished work (except in an abstract form) that is not under consideration for publication anywhere else, and all co-authors should have agreed to the submission. Manuscripts should be written in English.
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