Siderophores of fungi from Lipa clay loam soil, Philippines

Abstract

This research was conducted to isolate culturable soil-borne fungi from Lipa clay loam soil and identify the types of siderophores they produce. The frequency of fungal isolates was likewise compared across the soil strata. Soil samples were plated on Rose Bengal Agar (RBA) and incubated for five days. Morpho-culturally unique isolates were transferred in Potato Dextrose Agar (PDA) slants and identified using taxonomic keys and by ITS sequencing. Siderophores of each species were then characterized through colorimetric methods. Twenty-nine species of fungi were identified. Six isolates were Basidiomycetes, 1 Zygomycetes and 22 Ascomycetes. Among ascomycetes, two were teleomorphs: Chaetomium globosum Kunze and Emericella nidulans (Eidam) Vuillemin. Isolates were then characterized in terms of their ability to produce siderophores. Majority produced hydroxamate type of siderophores while only Aspergillus tamarii Kita produced all three types of siderophores. Six other species failed to produce any of the three types. Isolates may further be studied for their metal remediating capacity and other biological activities.