Impact of Enzymes and Toxins Potentiality of Four Aspergillus Species to Cause Aspergillosis

Abstract

Aspergillus species are the main causing agents of invasive apergillosis chest disease. Eighty isolates of Aspergillus species, A. flavus (20), A. fumigatus (15), A. niger (30) and A. terreus (15 isolates), previously isolated and identified from aspergillosis suspected patients at our lab in Assiut university hospitals, were assayed for their enzymes and toxins profile. The results revealed that, all of the tested isolates were able to utilize calf lung tissue and produce catalase and peroxidase enzymes. Meanwhile, 82.5-90% of the fungal isolates had the ability to produce protease, lipase, urease and phospholipase, whereas, 70% of isolates exhibited hemolytic activities. Thin layer chromatography (TLC) of the cleaned extracts of the tested isolates exhibited the ability of all A. flavus isolates assayed to produce aflatoxins B1 and G1, 53%, moreover, A. fumigatus isolates produced fumagillin and gliotoxin. On the other side, 43.3% and 23.3% of A. niger isolates produced ochratoxins and gliotoxin respectively. Virulence assay of 10 μl of gliotoxin standard and cleaned extracts of A. fumigatus toxic isolates showed necrotic area on Guinea Pigs lungs compared to the control. Thus, opportunistic fungi isolated from aspergillosis patients possess high enzymatic and toxic profile that might play an important role in their mycopathy.