However, microbial fermentations are been used for long time for industrial scale citric acid production. The citric acids can also be used in remediation aspects. Citric acids are used as chelating agents to remove heavy metals in soils (Sayer and Gadd, 2001). Fungal organic acids usually consisting one or more carboxylic groups which is
responsible for the chelating properties. The citric acids can effectively remove zinc, chromium and nickel from the soil (Elliott and Shastri, 1999; Wasay et al., 2001).