Screening and Characterization of Potential Fungi from Environmental Samples for Extracellular Phytase Production

Abstract

Phytases are enzymes of significant interest due to their ability to hydrolyze phytic acid, releasing inorganic phosphate that is essential for various biological processes. This study aimed to screen and characterize potential phytase-producing fungi isolated from environmental samples for extracellular phytase production. Various environmental samples were collected from different locations in the Khulna region. A total of 15 fungal isolates were obtained, and morphological and microscopic characterization aided in the preliminary identification of these fungal species. Screening for extracellular phytase production was conducted using a plate assay containing phytin as the sole phosphorus source. Five fungal isolates (Isolate 2, Isolate 3, Isolate 5, Isolate 11, and Isolate 12) yielded positive results in the phytase screening test. The total protein concentration of these five fungal isolates was determined using the TCA protein precipitation technique. Isolate 2 (8.84 µg/mL) and Isolate 12 (49.77 µg/mL) were selected for thermostability testing based on their higher protein concentrations. Both isolates exhibited positive results for thermostability, as evaluated through gradual temperature increases ranging from 4°C to 50°C. Notably, the phytase enzyme from Isolate 12 demonstrated 40% greater temperature stability compared to Isolate 2. Further studies will focus on the molecular characterization of Isolate 12 and its potential use as a feed additive. This research contributes to the discovery of potential fungal phytases with enhanced industrial applicability in various sectors.