Removal of estrogenic activity of 4‐tert‐octylphenol by ligninolytic enzymes from white rot fungi

Abstract

4‐tert‐Octylphenol (4‐t‐OP) was treated with the white rot fungus Phanerochaete sordida YK‐624 under ligninolytic condition with low‐nitrogen and high‐carbon culture medium. 4‐t‐OP completely disappeared after 5 days of treatment and the activities of ligninolytic enzymes, laccase and manganese peroxidase (MnP), were detected during this period, thus suggesting that the disappearance of 4‐t‐OP is related to these extracellular enzymes. Therefore, 4‐t‐OP was treated with laccase and MnP prepared from white rot fungi cultures. HPLC analysis demonstrated that 4‐t‐OP completely disappeared in the reaction mixture after 1 h of treatment with either laccase or MnP. Using the yeast two‐hybrid assay system, it was also confirmed that laccase and MnP substantially removed the estrogenic activity of 4‐t‐OP after 1 and 2 h of treatment, respectively. These results strongly demonstrate that ligninolytic enzymes are effective in removing the estrogenic activity of 4‐t‐OP. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 281–286, 2007.