Enzymes in Environment Management

• Published in: Emerging Trends in Environmental Biotechnology pp. 203 - 220
• Main Authors: Bhalla, Tek Chand, Thakur, Neerja, Sheetal, Monika, Bhatia, Shashi Kant, Raj, Jog
• Format: Book Chapter
• Language: English
• Published: United Kingdom CRC Press 2023; Taylor & Francis Group
• Edition: 1
• Subjects: PTE; Pah Degradation; TCDD; Polydiallyl Dimethyl Ammonium Chloride; Aromatic Contaminants; PAHs Bioaccumulation; Cyclohexane Carboxylic Acid; Food Waste Streams; AOPs; enzymatic treatments; Azo Reductase; Wood Treatment Facilities; Phosphotriesterases; Manganese Peroxidase; MFO; Recalcitrant Organic Pollutants; White Rot Fungi; Lignin Peroxidase Enzymes; Lignin Peroxidase; Parathion Hydrolase; Mixed Function Oxidases; industrial effluents; PAHs Production; Contaminants; microbial enzymes; Azo Dyes
• ISBN: 9781032030258; 1032030283; 1032030259; 9781032030289
• DOI: 10.1201/9781003186304-15

This chapter describes the effluent released in the environment from various industries, such as leather, textile, petroleum, food processing, paper, and pulp mill, with contaminants and their hazardous effects. The physico-chemical methods used to treat various types of environmental contaminants are coagulation, flocculation, chemical precipitation, chemical oxidation and reduction, advanced oxidation processes (AOPs), ozonation, sonolysis, photocatalysis, ion exchange and solvent extraction. These conventional methods used for the treatment of industrial effluents have many limitations due to the high concentration, cost and toxicity of chemicals involved and the formation of toxic by-products that adversely affect the environment. Microbial enzymes have potential applications in the remediation of industrial pollution as these are specific in action and eco-friendly in use. Therefore, enzymatic treatments of pollutants have been proposed as a potential alternative to physicochemical methods as they are highly selective, efficient, cost-effective and work over a wide range of pH, temperature and salinity. Due to the potential advantages of enzymatic treatment methods, recent research has focused on the development of enzymatic processes targeting effluents from a particular industry. The major categories of enzymes involved in the degradation of pollutants are hydrolases, oxidoreductases and halogenases. The enzymes, for example, laccase, tyrosinase, lignin peroxidase and Mn-peroxidase, are used for the treatment of phenols and aromatic compounds; lactases for dairy wastes; cellulases for paper and pulp wastes; laccase, peroxidases, cellulase and xylanase for textile wastes; phosphatase for heavy metals; and cyanide hydratase and cyanidase for cyanide treatment. Thus, the enzymes are promising candidates for industrial effluent treatment and remediation of polluted habitats. Microorganisms degrading a range of aliphatic, aromatic and heterocyclic compounds have been isolated, identified and their enzymes chemical pollutants degradations pathways have been well characterized. Microorganisms degrading a range of aliphatic, aromatic, and heterocyclic compounds have been isolated, identified and their enzymes chemical pollutants degradations pathways have been well characterized. All these are present as pollutants in the effluents of such industries. The main enzymes involved are discussed in the following subsections. The most commonly used enzymes in food waste treatment are discussed in the following subsections. Peroxidases and laccases are the enzymes that can perform the task to treat the bleaching effluents. Kraft mill effluents colors can be removed by the use of horseradish peroxidase and lignin peroxidase enzymes. The cellulolytic enzymes can be used in the treatment of sludge from pulping and ink removal operations, thereby converting sludge into fermentable sugars.