Although it is a protein, this enzyme is not damaged by heat. The crude extract consist of two crystallized enzymes called ' papain ' and ' chymopapain '. The enzyme is similar to pepsin and hence it helps to digest protein in the body. It is therefore used to relieve indigestion. Externally the papaya latex is an irritant to the skin and internally it causes severe gastritis.
Some people are allergic to various parts of the fruit.
Papain can induce asthma and rhinitis and the related enzyme carpaine can cause paralysis, numbing of the nerve centers and cardiac depression. Papain has an anticoagulant effect. Injection of the extract in a dog increases prothrombin and coagulation threefold. It is also claimed that the enzyme eliminates necrotic tissues in chronic wounds, burns and ulcers. As mentioned before crude papain is also of commercial importance in the brewery industry, in the food industry and in the textile industry.