First molecular report of causative agent of otomycosis due to Aspergillus luchuensis

Mycoproteins and their health-promoting properties: Fusarium species and beyond

Filamentous fungal mycoproteins have gained increasing attention as sustainable alternatives to animal and plant-based proteins. This comprehensive review summarizes the nutritional characteristics, toxicological aspects, and health-promoting effects of mycoproteins, focusing on those derived from filamentous fungi, notably Fusarium venenatum. Mycoproteins are characterized by their high protein content, and they have a superior essential amino acid profile compared to soybeans indicating excellent protein quality and benefits for human nutrition. Additionally, mycoproteins offer enhanced digestibility, further highlighting their suitability as a protein source. Furthermore, mycoproteins are rich in dietary fibers, which have been associated with health benefits, including protection against metabolic diseases. Moreover, their fatty acids profile, with significant proportions of polyunsaturated fatty acids and absence of cholesterol, distinguishes them from animal-derived proteins. In conclusion, the future of mycoproteins as a health-promoting protein alternative and the development of functional foods relies on several key aspects. These include improving the acceptance of mycoproteins, conducting further research into their mechanisms of action, addressing consumer preferences and perceptions, and ensuring safety and regulatory compliance. To fully unlock the potential of mycoproteins and meet the evolving needs of a health-conscious society, continuous interdisciplinary research, collaboration among stakeholders, and proactive engagement with consumers will be vital.

Aspergillus welwitschiae; a predominant otomycosis agent, new epidemiological and antifungal susceptibility data from Iran

BACKGROUND

Black aspergilli (section Nigri) are predominate etiologic agents of otomycosis, however, there is controversy in the exact differentiation of species. For several decades Aspergillus niger is considered the main otomycosis etiologic agent. Recently calmodulin gene has been accepted as a more suitable gene for the accurate assignment of Aspergillus species. Therefore, it is found that A. welwitschiae and A. tubingensis are the main otomycosis agents based on calmodulin gene sequencing.

AIMS

The objective of the study was to isolate and identify black aspergilli from otomycosis using the calmodulin gene and their susceptibility was evaluated against several antifungals.

METHODS

134 clinically confirmed patients with otomycosis were sampled and specimens were cultured on Sabouraud dextrose agar (SDA) at ambient temperature. Black aspergilli were screened based on colony morphology on SDA and microscopy features and then subjected to sequencing using calmodulin primers. Moreover, antifungal susceptibility for isolates was applied based on CLSI M38 3rd edition.

RESULTS

132 (98.5%) of patients had positive cultures for different species of molds or yeasts. Most of the patients (30.3%) ranged from 31 to 40 years, and 56.1% of them were female. Aspergillus section Nigri was the most prevalent fungal pathogen and of 86 isolates, 60.5% isolates were identified as A. welwitschiae, A. tubingensis, 31 (36.0%), A. niger (sensu stricto), 2 (2.3%), and A. neoniger 1 (1.2%). According to the maximum likelihood method, all isolates of A. tubingensis and one isolate of A. neoniger were included in the A. tubingensis clade. On the other hand, the clade of A. niger/A. welwitschiae contains, all isolates of A. welwitschiae, two A. niger (sensu stricto) isolates, and 36 isolates from other countries. Aspergillus welwitschiae was more sensitive to luliconazole, voriconazole, and amphotericin B compared to A. tubingensis. 78.8% of A. welwitschiae strains were classified as non-wild type to nystatin compared to 35.5% of A. tubingensis. Moreover, 3.2% of A. tubingensis strains were non-wild type against amphotericin B. The isolates of A. tubingensis were more sensitive to itraconazole than A. welwitschiae.

CONCLUSIONS

It is concluded that in contrast, to the previous study A. welwitschiae from section Nigri is the most causative agent of otomycosis followed by A. tubingensis. In addition, the isolates of A. welwitschiae were more sensitive to luliconazole, voriconazole, and amphotericin B compared to A. tubingensis. Whereas, the isolates of A. tubingensis were more sensitive to itraconazole than A. welwitschiae. On the other hand, 78.8% and 35.5% of A. welwitschiae and A. tubingensis strains were classified as a non-wild type against nystatin. Also, 3.2% of A. tubingensis strains were non-wild type against amphotericin B. All A. welwitschiae were included in the A. niger/A. welwitschiae clade, associated with different clinical and environmental species from different countries.

Black aspergilli as causes of otomycosis in the era of molecular diagnostics, a mini-review

Otomycosis refers to the fungal infection of the external auditory canal, and less commonly the middle ear. A wide range of fungi can cause this disease, however, the most common etiologies are species of Aspergillus and Candida. Until recent years, Aspergillus niger was thought to be the prevailing species of the genus Aspergillus that causes otomycosis. Using molecular methods, now, it is known that Aspergillus section Nigri comprises several morphologically similar species and all black Aspergillus isolates are not necessarily equivalent to Aspergillus niger. In this review, we focus on the species within the Aspergillus section Nigri and their role as the causative agents of otomycosis.