Extraction and Purification of Collagenase Enzymes: A Critical Review

Problem statement: Enzymes have vital roles in several industrial processes (foods, cosmetics, nutraceuticals and pharmaceuticals) due to their highly selective nature and high activity at very low concentrations. Recent efforts to identify new sources of useful enzymes have been concentrated on the marine environment because of the potential to make use of processing wastes. About 35-50% of the mass of the fish caught is a waste that is disposed off at sea or in landfills. The extraction of enzymes from fish processing waste can reduce environment problems and improve the economics of the fish industry. Collagenases are a group of enzymes that can be extracted from fish waste. Approach: Comprehensive reviews of the literature on the extraction, purification, characterization and use of collagenases was carried out. Results: Collagenases have different molecular weights based on their types and sources. They have the ability to break down the peptide bonds in collagen at physiological pH. They are classified into two types: serine and metallocollagenase. Collagenolytic activities have been shown at a wide range of temperatures (20-40°C) and pH (6-8). Many activators can be used to achive collagenase activity including 4-Aminophenylmercuric Acetate (APMA), trypsin, potassium or sodium thiocyanate, iodoacetamide and potassium iodide. Dithiothreitol (DTT), mercaptoethanol, ethylendiaminetetracetic acid, ophenanthroline and cysteine inactivate the enzyme. Collagenases enzymes can be extracted with a variety of techniques using different buffering systems (tris-HCl, sodium bicarbonate, calcium chloride and cacodylate). All techniques involve the use of ammonium sulphate fractionation and centrifugation to precipitate the enzyme. Collagenases are normally purified using chromatographic techniques such as gel-filtration, ion-exchange and affinity column chromatography. Collagenase can be assayed with a number of methods, including: colorimetric absorbance, viscometry, radioactivity and fluorescence spectroscopy. Collagenases are partly responsible for toughness in red meats and are used as tenderizers in food industry, have application in the fur and hide tanning to ensure uniform dying of leather, used in medicine to treat burns and ulcers, eliminate scar tissues, transplantation of organs. Conclusion: Understanding of the nature of the enzymes and identifying the most suitable resources and the methods for their extraction and purification will have significant impact on the fish processing, food and medical industries.