Production of L-Asparaginase by Yemeni Filamentous Fungi

Abstract

Yemen with its diverse climatic regions represents a rich resource for bioactive compounds obtained from microorganisms. This study was designed to screen fungal isolates obtained from the Microbiology branch, Biological Sciences Department, Faculty of Science, Sana’a University for their ability to produce L-asparaginase enzyme. In preliminary screening for L-asparaginase, among 77 fungal isolates about 29 fungal isolates representing 37.66% were high producers of L-asparaginase. These fungal isolates belonged to the genera Aspergillus, Eupenicillium, Fusarium, Penicillium, and Stachyobotrys. These 29 fungal isolates were screened for their ability to produce L-asparaginase using the agar well diffusion method. 12 fungal isolates out of 29 showed the ability to produce extracellular L-asparaginase. These isolates belonged to 8 species which were: A. sulphurs, A. ustus, F. sacchari, P. chrysogenum, P. citrinum, P. corylophilum, P. melinii, and P. subturcoseum. Only 5 isolates were obtained for the determination of enzymatic activity, among them P. chrysogenum showed the highest activity (279.8696U ml-1) followed by A. ustus (170.9435U ml-1). This finding is the first report on the L-asparaginase production from filamentous fungi in Yemen.