Environmental pollution is becoming one of the major threats around the world because of the release of toxic and hazardous substances from food, pharmaceutical, and other industries as well. These wastes are mainly dumped indiscriminately which ultimately reached water bodies, thereby affecting marine ecosystem. Therefore, effective effluent treatment is an important step which can help in conserving our water resources. White rot fungus (WRF) have been shown to degrade and mineralize a wide variety of wastes because of their nonspecific extracellular lignin mineralizing enzymes (LMEs). These enzymes are used for the decolorization of synthetic dyes. They help in the degradation of pesticides, polycyclic aromatic hydrocarbons (PAHs), and pharmaceuticals wastes like- anti-inflammatory, lipid regulatory, antiepileptic drugs, endocrine disrupting chemicals, etc. They also help in degrading the food waste and convert them into useful products which can be used as food, feed, fodder; some of these wastes are lignocellulosic waste, viticulture waste, olive mill waste, molasses waste, etc.
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Wastes from different industries like food industry, pharma industry, paper and mill industry, dye industry, etc. are hazardous in nature and their proper treatment is necessary. These wastes after conventional treatment are mainly dumped into water bodies or spilled on the land. The organic micropollutants in the effluent of waste water treatment plants (WWTPs) still include toxic substances which usually settle on the banks of the river or are present on the soil (Marco-Urrea, Pérez-Trujillo, Vicent, & Caminal, 2009). Generally, conventional biological treatment technologies do not remove pollutants effectively. These pollutants can adversely affect key biotransformation process of other pollutants, like denitrification, nitrogen fixation, degradation of organic compounds, etc (Heberer, 2002; Rooklidge, 2004). Therefore, an efficient technique for their total destruction is very necessary, and one such process is bioprocess involving micro-organisms and their enzymes as biocatalysts. This technique is cost effective with attractive properties, such as low energy requirements, easy process, broad range specificity and operational over wide range of pH, temperature and ionic strengths (Torres, 2003). White rot fungi (WRF) and their lignin modifying enzymes (LMEs) have been used extensively for the treatment of these toxic compounds. They help in the bioremediation and biodegradation of many toxic compounds like dye stuffs, PAHs, pesticides, antibiotics, phenols, polychlorinated biphenyls (PCBs), anti-depressants, endocrine disrupting chemicals, agricultural waste, etc (Torres, 2003; Mayer, 2002; Reddy, 1995; Pointing, 2001). WRF includes basidiomycetes and litter-decomposing fungi which are capable of extensive aerobic lignin polymerization and mineralization. They produce extracellular enzymes which help in the degradation of wide range of xenobiotics because of their low substrate specificity. Peroxidases are widely distributed in nature. They (EC 1.11.1.7) are heme proteins and contain iron (III) protoporphyrin IX (ferriprotoporphyrin IX) as the prosthetic group. Their molecular weight ranges from 30,000 to150,000 Da. These are a group of oxidoreductases that catalysethe reduction of peroxides, such as hydrogen peroxide and the oxidation of a variety of organic and inorganic compounds. They secrete low molecular weight mediators that enlarge the spectrum of compounds they are able to oxidize. The LMEs of WRF are lignin peroxidases (LiP, E.C. 1.11.1.14), manganese- dependent peroxidases (MnP, E.C. 1.11.1.13), versatile peoxidases (VP, E.C. 1.11.1.16) and laccases (Lac, E.C. 1.10.3.2). These enzymes are produced during WRF secondary metabolism since lignin oxidation provides no net energy to the fungus (Cabana, 2007).