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Introduction: Although, Rhizopus species, are the main causative agents of mucormycosis, we know a little about these pathogens. We investigated the virulence potential of Rhizopus arrhizus and R. microsporus strains, obtained from a wide selection of clinical and environmental sources, in Galleria mellonella larvae and a mice model. Methods: In this experiment, a total of 26 strains, 13 for each species of R. microsporus, R. arrhizus were tested in larvae with final concentration of 106/ml per strain. Eight strains were tested in mice model. Inoculated samples were monitored in insect larvae for 6 days and in mice for 14 days. Statistical data were performed using Graphpad Prism software (GraphPad Software, San Diego, CA). Survival data of the samples were plotted using Kaplen-Meyer diagrams and analyzed using log rank test P value was considered 0.05%. Results: R. arrhizus showed higher virulence compare to R. microsporus in both models. No specific difference was seen in pathogenicity between the two varieties of R. arrhizus. Virulence was not affected by source of isolation or production of toxin in some strains of R. microsporus. Virulence pattern was similar in both models. Conclusion: Considering the mortality rate which was happened with strains from environmental sources, we conclude that these fungi have an opportunistic nature, which make them pathogen in susceptible hosts in favorite conditions. Larvae model showed reliable results compare to mice model.

Background: Nowadays, the prevalence of onychomycosis caused by non-dermatophyte molds is increasing. As Aspergillus is the most common etiologic agents of the disease, this study was performed to evaluate the susceptibility of clinical isolates of Aspergillus as the cause of onychomycosis to itraconazole, voriconazole, and amphotericin B. Methods: This cross-sectional study was performed on 50 Aspergillus strains isolated from the patients with onychomycosis referred to diagnostic laboratories of university hospitals in Mashhad, Iran. According to the phenotypic and molecular analysis of Aspergillus isolates, the most frequent species was Aspergillus flavus (A. flavus) with 34 cases. The drug susceptibility test was performed according to Clinical and Laboratory Standards Institute-M38-A2 (CLSI-M38-A2) protocol, and the minimum inhibitory concentration (MIC) of the drugs was determined. Findings: From 50 patients with dystrophic nails, 13 were men and 37 were women. 15 patients had fungal infection of fingernails, and 33 patients had fungal infection on toenails; 2 patients had both infections of finger and toe nails. 14.7% of A. flavus isolates with MIC > 2 μg/ml to amphotericin B were considered as resistant clinical isolates. The sensitivity to itraconazole and voriconazole was 100%. MIC90 of amphotericin B, itraconazole, and voriconazole were obtained by broth microdilution method for A. flavus species as 4, 0.25, and 1 μg/ml, respectively. Significant difference was observed in MIC between itraconazole and amphotericin B (P < 0.050). Conclusion: All Aspergillus species are susceptible to itraconazole and voriconazole, and these two drugs are more effective than amphotericin B on Aspergillus species. Due to the different susceptibility of these species to antifungal agents, it is necessary to perform drug susceptibility testing in order to select the appropriate drug.

Introduction: Little is known about the pathogenicity and virulence properties of the Rhizopus species used in food fermentation. This study aimed to investigate the virulence potential of Rhizopus arrhizus and R. microsporus strains obtained from a wide selection of clinical and environmental sources in an embryonated chicken egg model. Materials & Methods: In total, 26 strains (13 strains from each species) were inoculated in embryonated eggs with final concentration of 106 spore/ml/egg. The eggs were inoculated (0.1 ml) through chorio-allantoic membrane in day 10 and incubated at 37.6 °C and 60% humidity and monitored for 7 days. Ethics code: IR.MUMS.fm.REC.1396.457 Findings: The mortality rate for R. microsporus was slightly higher than that of R. arrhizus. The ability of R. arrhizus and R. microsporus to cause infection was strain-specific but source-independent in the embryonated chicken eggs. The presence of endosymbiont bacteria (Burkhulderia) in some strains of R. microspores did not show any effect on their virulence. Discussion & Conclusions: The occurrence of virulence in strains isolated from fermented food indicates the opportunistic nature of these fungi and possibility of a public health risk for consumers.

Background: Dermatophytes are a group of fungi that attack keratinous tissues of the skin, hair, and nail in humans and animals, and cause infections called dermatophytosis (tinea). Since identification of pathogenic fungi at the species level is essential for the detection of the source, control and prevention, and identifying epidemiology of infection, it is necessary to use specific and sensitive diagnostic methods to identify the causes of dermatophytosis. Methods: The clinical samples (skin, nail, and hair) of patients with dermatophytosis in Mashhad City, Iran, were cultured in Mycosyl Agar culture media, and the DNA of obtained dermatophyte colonies were extracted by specific kit. The internal transcribed spacer (ITS) gene was amplified and sequenced by ITS1, ITS4 primers. Finally, the sequencing results were analyzed using SeqMan software, and were compared with the data of the global genebank. Findings: In this study, 80 dermatophyte isolates were sequenced, which included 9 dermatophyte species as 23 (28.8%) Trichophyton (T.) interdigital, 18 (22.5%) T. tunsorans, 10 (12.5%) Epidermophyton fluccosum, 10 (12.5%) of T. mentagrophytes, 8 (10%) Microsporum canis, 4 (5%) T. rubrum, 4 (5%) T. benhamiae, 2 (2.5%) Nannizzia (N.) fulvum, 1 (1.2%) N. persicolor. Conclusion: According to report the rare species of dermatophytes in this study, the use of molecular methods such as sequencing of the ITS gene can determine the diversity of dermatophytes in a region more precisely than morphological methods.

Background and Aim: The occurrence of fungal species resistant to antifungal drugs and also their numerous side-effects have persuaded researchers to work on new therapeutic methods. The aim of the present study was to assess anticandidal activities of aqueous and methanol. extracts of walnut fruit, peel, and leaves on different Candida species. Materials and Methods: In the current study, antifungal effects of aqueous and methanolic extracts of fruit peel and leaves of walnut (Juglans regia) against four Candida species (Candida albicans, Candida glabrata, Candida tropicalis and Candida krusei) were examined using broth microdilution method. The tested fungal species were associated with different concentrations of the plant extracts , and then, the Minimum Inhibitory Concentration (MIC) and Minimum Fungicidal Concentration (MFC) of these extracts were obtained for tested Candida species. Results: Both aqueous and methanol extracts of fruit peel .and leaves of walnut showed antifungal effects against candida species. The MICS of fluconazole, clotimazole, nystatin and aqueous and methanol extracts of fruit peel and leaves of walnut for different Candida species were 6.25-50, 3.125-25, 12.5-50 and 3.125- 25 mg/ml, respectively. MFCs of methanol extracts of fruit peel and leaves of walnut were 6.25-25 mg/ml. The aqueous extracts of fruit peel and leaves of walnut were without fungicidal effects only through inhibiting fungal growth. Conclusion: It was found that methanol extracts of walnut leaves and peels contain compounds with thrapeutic potential against candida species and it looks promising that some effective antifungal agents with minimal side effects from walnut leaves and pills extract can be obtained in the future.