Chromium (Cr) is widely used in anthropogenic activities and high amount of chromium is released into the environment. There are many conventional remediation methods developed for Cr(VI), but they are costly and lack efficacy. Hence, mycoremediation could be used as an alternative to remediate Cr(VI) in the environment. The objective of this research is to isolate the potential soil fungi for Cr(VI) bioremediation by means of Cr(VI) tolerance test. The collected soil fungi were screened with rose bengal agar (RBA) and cultured on potato dextrose agar (PDA) to obtain pure cultures. The isolated fungi underwent chromium tolerance test in potato dextrose broth (PDB) with potassium dichromate concentrations up to 500 ppm. After 14 days of culturing, the dry weight of mycelium was measured. The ability of the fungi to remove Cr(VI) was determined through spectrophotometry at 540 nm using diphenylcarbazide complexing agent. The result showed that all fungi can tolerate Cr(VI) up to a concentration of 500 ppm and were able to reduce certain percentage of Cr(VI) in PDB medium. Out of 8 fungi species that were isolated, Aspergillus tamarii, Trichoderma atroviride and Aspergillus niger were identified to be potential fungi based on their satisfactory biomass growth which were 0.20 g, 0.18 g and 0.23 g respectively, indicating that they can tolerance high amount of Cr(VI). The percentages of Cr(VI) reduction were 57.3%, 50.2% and 40.8% for the three aforementioned species, respectively. Although A. niger had the highest biomass growth it exhibited the lowest Cr(VI) reduction, which could be due to the biosorption mechanism in A. niger which allows its biomass production even in the presence of Cr(VI). Hence, it could be concluded that A. tamari is the most ideal fungus for remediating Cr(VI).
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