Xylanase-producing Fungi Diversity in the Soil of Jeddah, Saudi Arabia

Abstract

Aims: To assess the diversity of xylanase-producing fungi in the soil of Jeddah, Saudi Arabia, as well as the xylanase-producing potential of the isolated fungi. Methodology: A total of ten soil samples were collected from five different sites in the Jeddah district, Saudi Arabia. The soil samples were subjected to a soil dilution assay to estimate the total fungal counts and density percentage of isolated fungal species on xylan agar medium. Further, the xylanase activity of the isolated fungi was assayed using xylan from birch wood (0.01%) as the substrate. Results: A total of twelve fungal species (A. alternata, A. flavus, A. niger, A. terreus, B. cinerea, F. roseum, F. solani, P. chrsogenum, P. italicum, P. canescens, R. microsporus, and R. oryzae) related to six genera were isolated from the ten soil samples. The population of different fungi and the isolated species varies at different sites. Overall, A. niger was isolated with the highest occurrence and population density (37.2%). Moderate occurrence was shown by both P. chrsogenum (18.6%) and R. microsporus (23.5%). The maximum significant value (P=0.05) of extracellular xylanase enzyme was observed in the culture filtrate of A. alternata (0.58 units/ml), whereas the minimum value was detected with F. roseum (0.20 units/ml). Conclusion: The soil in the Jeddah district of Saudi Arabia has a good population of xylanase-producing fungi. The relative density of the isolated fungi varied in different soils. The isolated fungal species were capable of producing xylanase. The isolated fungus, A. alternata, should be explored further for its extracellular xylanase production for use in biotechnology applications.