Enzymes are proteins that are found in every living organism: man, animals, plants and microorganisms. Nature — including human digestive systems — relies on enzymes to break down proteins, starches and fats. The same types of enzymes can be used in detergents to break down the stains that bind to fabrics.
Enzymes are produced by living organisms (though they are not themselves alive) and are used in cleaning to "digest" organic matter, proteins, oils and grease. The use of enzymes in laundry detergents since the 1960s has yielded products that remove organic, oil-based and protein-based stains and work well in cold water.
Enzyme-containing products can consume and remove residue from feces, vomit and urine. Enzymes are also effective in drain cleaning products to help dissolve organic matter and eliminate bacterial odor.