Transformation of Hormones In Soil Mediated by Enzymes From White-Rot Fungi.

Environmental pollution with hormones has drawn more attention of the public and regulatory agencies. Concentrated animal feeding operations (CAFO-s) are among the major sources of these hormones released into soil via animal manure land-application practices. Recent studies have indicated the potential of adverse human and ecological health effects caused by the presence of hormones in soil and aquatic systems. Among sexual steroidal hormones 17-beta estradiol (E2) is the most potent, and is persistent in environment. Earlier studies have shown that a number of persistent organic pollutants can be transformed in soil by white-rot fungi such as Phanerochaete Chrysosporium, and Trametes Versicolor, and it is proposed that these fungi may be useful in soil remediation. Extracellular enzymes released by these fungi participate in oxidative coupling reactions resulting in humification of hormones. We conducted experiments to examine the transformation of a representative hormone, 17-beta estradiol in a well characterized sandy loam soil to which Phanerochaete Chrysosporium was inoculated and cultured. Significant transformation of 17-beta estradiol was observed. Attempts were made to characterize the products, elucidate the transformation pathways, and identify the responsible enzymes. The primary objective of this study is to develop a cost-effective, efficient and eco-friendly bioremediation technique using fungal systems to mediate hormones in soil.