Chromium (VI) bioremediation potential of dark septate endophytic (DSE) fungi

Abstract

Manufacturing activities release an extensive quantity of wastes containing hazardous materials like hexavalent chromium [Chromium VI, Cr(VI)] into the surroundings, threatening human health and the ecosystem. Fungi can be utilized as an efficient Cr(VI) remediation implement. The six isolates of dark septate endophytic (DSE) fungi (KSP, CPP, PP, DD, K.III.3.4, TKC) were evaluated for their tolerance and removal ability of various Cr(VI) concentrations (10, 30, and 50 mg/L). The quantification of Cr(VI) removal was analyzed using the 1,5-diphenylcarbazide method by UV-Visible spectrophotometer (Hitachi-U 2900). The results showed that all the DSE isolates were highly tolerant to Cr(VI) concentrations up to 50 mg/L with a tolerance index (TI) of 0.89-1.22. These fungal strains showed no significant growth (p > 0.05) from the controls. Furthermore, all test fungi exhibited an efficient removal capacity of up to 99% of 50 mg/L Cr(VI). The results indicated that DSE fungi are potential agents for bioremediation of Cr(VI) polluted surroundings like manufacturing wastewater. It is the first report on the ability of DSE fungi to remove Cr(VI).