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Goldfish were exposed to either treated municipal effluent (FE wastewater) or reuse water produced through membrane ultrafiltration (MF reuse water) or membrane ultrafiltration followed by activated carbon filtration (MCF wastewater) for up to 90 days. The xenobiotics present in the wastewater were identified using gas chromatography - mass spectroscopy and the efficacy of their removal by membrane ultrafiltration and activated carbon filtration were determined. At various time points post-exposure to wastewater or reuse water the following biological parameters were assessed: vitellogenin (Vtg) induction, immune gene expression, and mitogen-induced proliferation of blood leukocytes. Membrane ultrafiltration alone did not remove xenobiotics from FE wastewater, while activated carbon filtration efficiently reduced the levels of most xenobiotics. Vitellogenin was induced in fish exposed to both FE wastewater and MF reuse water, but not in fish exposed to MCF reuse water. Messenger ribonucleic acid (mRNA) expression of select immune genes (tumor necrosis factor alpha, colony stimulating factor receptor-1) were up-regulated in FE and MF exposed fish on days 7 and 21 post exposure, while Toll-like receptor 22 mRNA level was similar in fish exposed to wastewater or control water. Prolonged exposure of fish to FE and MF wastewaters caused a significant reduction in the mitogen-induced proliferation of blood leukocytes. Our results suggest that goldfish may be used as biosentinels for xenobiotics present in wastewater and reuse water. [ABSTRACT FROM AUTHOR]

The use of enzymes for the treatment or the removal of environmental and industrial pollutants has attracted increasing attention because of their high efficiency, high selectivity, and environmentally benign reactions. Of these enzymes studied for such purposes, extracellular fungal peroxidases, such as lignin peroxidase, manganese peroxidase and Coprinus cinereus peroxidase, and fungal laccases are the two major classes of enzymes that have been evaluated for the removal of toxic phenolic compounds from industrial wastewater and the degradation of recalcitrant xenobiotics. Numerous reports have been published recently on the improvements of the production of these enzymes, such as discovery of new fungal strains, modification of growth conditions, use of inducers, and use of cheaper growth substrates such as agricultural and food wastes. In this review, these recent advances in the production of extracellular fungal peroxidases and laccases, along with brief summaries of background of these enzymes and their applications, are discussed. [ABSTRACT FROM AUTHOR]