Biological Removing and Isothermal Absorption Studies of Copper by Fungal Biomass of Trichoderma

Abstract

The environment suffers from the harmful effects of industrial pollution, including heavy metals. Nowadays, due to the low cost, high efficiency and environmental sustainability, biological techniques have been used to reduce or eliminate pollutants. Trichoderma species are free living fungi existing in the soil that produce antimicrobial materials. They inhibit the growth of pathogenic fungi and play a useful role in agriculture and ecosystem management. In this study, the uptake of copper ions was studied by three species of Trichoderma influenced by environmental variables such as the pH and the concentration of metal ions in a liquid medium containing potato extract and dextrose. Three different pH values (5, 7, 9) were selected for the solution and the initial concentration of copper ions was selected 1, 50, and 100 ppm. The remaining amounts of Cu in the media were measured after two months of exposure to pollutants with fungi; the measurements were performed using atomic absorption. Results showed that all three fungal species were able to absorb and reduce the amount of Cu in all three pH values; some case, their performances varied depending on the species as well as the culture conditions. T. harzianum species had the maximum efficiency for removing copper (79.92%), (3.94 mg/g, at fungal dry weight). Based on our results, the most efficiency of the three fungal species was obtained at the alkaline pH (78.09%). Also, Frindlych and Langmuir isotherm models were used to obtain isotherm equilibrium curves. Our results showed that the Langmuir isotherm model at pH 9 and the initial concentration of 50 ppm for copper ions was the most consistent.