Applied Microbiology

Biography

Biography: Parvin Dehghan

Abstract

Despite intensive investigation, the taxonomy of Aspergillus is still highly complex. Recent data indicate that several of the species of this genus cannot be distinguished based on morphological or molecular methods, alone. Aspergillus section Flavi includes more than 25 species and this number is likely to increase significantly in the near future because of increasing application of the phylogenetic species concept based on DNA sequence data rather than on visible morphological characters. A.oryzae and A. sojae species have been used for centuries to make traditional foods and are generally regarded as Safe. The data support the concept that they are derived (domesticated) from the naturally occurring A. flavus and A. parasiticus through adaptation in food industry fermentation. These two latter species produce the potent carcinogen aflatoxin and show many phenotypic similarities with the non-aflatoxignic species. The source of A.parasiticus is soil and it has not been isolated from infections. A. flavus is the major agent responsible for fungal sinusitis, keratits and onychomychosis in tropical and subtropical areas and surpasses A. fumigatus (belongs to section Fumigati) a common etiologic agent of aspergillosis. The genomic size of A. flavus is bigger than the A. fumigatus and that is believed the latter has lost some parts of its genome during the lifetimes. Identification of the organisms are more complex and a combination techniques including morphological characterization, physiological behaviors and molecular methods or an ITS based sequencing strategy are necessary to identify them.