Cleaning agents generally separate soils from fabric or surface substrate by dissolving or suspending them in a water or solvent liquid solution to be carried away when the solution is removed. The cleaning action of the primary formulation components is supplemented by additives to optimize the performance of the cleaners.
Biological additives are used to break down organic soils into smaller particles so that the soils are more readily separated and emulsified by surfactants for subsequent removal. Low levels of residual organic soils may often remain on surfaces due to incomplete solubilization or suspension of imbedded soils or incomplete rinsing of the surface. Biological additives impart a residual activity to the cleaned surface allowing for a slow removal of deeply embedded soils.
Biological additives function through the action of stabilized extracellular enzymes - enzymes that act outside the body of the microbe that produced them. These enzymes may be added as a separate component of the cleaning product or they may be produced as required by microbes added as a component of the cleaning product. Enzymes are organic catalysts found in nature. These catalysts hasten specific chemical reactions. Each enzyme selectively speeds the breakdown of a single type of chemical bond. Four classes of enzymes are commonly used in cleaning: (1) protease which breaks down protein, (2) amylase which breaks down starch; (3) lipase which degrades fats and oils, and (4) cellulase which breaks down cellulose. Microbes are able to detect the organic soils present and, provided they have the genetic capability, produce the specific enzymes needed to degrade those organics.
Enzymes are natural catalysts produced by all living organisms for control of metabolism and growth. They control the rate at which chemical reactions occur. We can now harness specific enzymes produced through fermentation processes to speed a wide range of industrial reactions.
Enzymes help speed and increase the performance of cleaning products in a wide range of applications. Most consumer laundry detergents contain enzymes to help remove stains, increase whiteness, eliminate fabric pills, and prevent resoiling. The inclusion of enzymes in laundry detergents also allows for shorter wash cycles and lower wash temperatures while ensuring the desired cleaning result, thus, providing energy savings Enzymes are also used to improve the performance of automatic dishwashing products by helping to remove protein deposits, starch films, and food particles.
Enzymes perform well under mild temperature and mild pH conditions and are therefore ideally suited for cleaning sensitive materials such as membrane filtration systems and highly sensitive medical equipment such as endoscopes. Commonly used in some food processing facilities, enzyme cleaning removes the residual organics and assists in effective cleaning of equipment.
Bacteria are nature’s primary decomposers. Their action helps nature recycle nutrients to be used again. They act by producing specific enzymes capable of breaking down organics present in their environment.
Most microorganisms used in cleaning applications are Bacillus strains. Bacilli are (excellent producers of extracellular enzymes) and they are resistant to a wide range of formulation ingredients. They produce encapsulated spores that remain inactive for long periods providing shelf stable products. Once exposed to organic substrates they germinate and produce the enzymes required to breakdown the specific organics present. Germination requires some time and thus enzyme cleaning is not ideal for cleaning processes that must occur very quickly, however, once germinated microbes and their extracellular enzymes will continue to act as long as organics are present and conditions favorable.