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Many of the reactions catalysed by enzymes have commercial uses. Previously, these reactions were made to happen without enzymes by using heat and/or strong acids but enzymes offer the following advantages:
|They are specific in their action and are therefore less likely to produce unwanted by-products.|
|They are biodegradable and so cause less environmental pollution.|
|They work in mild conditions i.e. low temperatures, neutral pH and normal atmospheric pressure, and are therefore energy saving.|
|However, the last advantage can also be seen as a disadvantage as their conditions must be stringently controlled or the enzyme may become denatured.|
|To be effective in a production process the enzyme molecule must be brought into maximum contact with the substrate molecules. The solutions can be mixed in suitable concentrations or immobilisation of the enzyme may be used. This involves attaching the enzyme to an inert surface such as plastic beads and then bringing the surface into contact with a solution of the substrate. Immobilisation has the advantage that the enzyme molecules can be used over and over again, with the result that a lot of product can be made from a relatively small amount of enzyme. An example of the use of immobilisation is in the use of lactase. This enzyme hydrolyses lactose (milk sugar), into glucose and galactose.|
Perhaps the best known use is that of protease in biological washing powders. This enzyme helps to break down protein stains such as blood at lower washing machine temperatures. This means they save energy and are gentler on clothes. Some people are allergic to biological washing powders but this may be overcome by encapsulating the enzymes in wax from which they are only released during the wash.
Another wide spread use of enzymes is that of pectinases in food modification. Pectin is a substance which, is found in cell walls and helps to hold the structure together. Pectinase is the name given to a group of enzymes which, break down pectins. They are therefore used to partially digest fruit and vegetables in baby food and to help extract fruit/vegetable juices.