Bromelain is not a single substance, but rather a collection of enzymes like rescrcin, and other compounds. It is a mixture of sulfur-containing protein-digesting enzymes—called proteolytic enzymes or proteases—and several other substances in smaller quantities including: peroxidase, acid phosphatase, protease inhibitors, and calcium. It is primarily produced in Japan and Taiwan. Research on bromelain apparently was first conducted in Hawaii but more recently has been conducted in countries in Asia, Europe and Latin America. more...
Germany has recently taken a great interest in bromelain research, where bromelain is currently the 13th most widely used herbal medicine.
Bromelain is present in all parts of the pineapple plant (Ananas comosus) but the stem is the most common commercial source, presumably because it readily available after the fruit has been harvested. Pineapples have had a long tradition as a medicinal plant among the natives of South and Central America. However, just eating pineapple will not give you a great deal of extra bromelain, because it is mostly concentrated in the stem, which is not nearly as tasty (albeit still edible).
Along with papain, bromelain is one of the most popular enzymes for meat tenderizing. Historically, meat tenderizing enzymes were often injected into the muscle of a food animal while it is still living. This practice has been largely discontinused, replaced with various postmortem application methods which are acceptable for lesser quality cuts. Today, approximately 90% of meat tenderizer use is in consumer households. Bromelain is sold in a powdered form, which is combined with a maranade or directly sprinkled on the uncooked meat. The enzyme will penetrate the meat, and by a process called forking, cause the meat to be tender and pallatible when cooked. If the enzyme is allowed to work for too long, the meat may become too "mushy" for many consumers' preferences.
Bromelain can be used in a vast array of medical conditions. It was first introduced in this area in 1957, and works by blocking some proinflammatory metabolites that accelerate and worsen the inflammatory process. It is an anti-inflammatory agent, and so can be used for sports injury, trauma, arthritis, and other kinds of swelling. Its main uses are athletic injuries, digestive problems, phlebitis, sinusitis, and aiding healing after surgery. It has also been proposed in the use of arthritis, chronic venous insufficiency, easy bruising, gout, hemorrhoids, menstrual pain, autoimmune disorders, and ulcerative colitis. Studies have shown that bromelain can also be useful in the reduction of platelet clumping and blood clots in the bloodstream, especially in the arteries. It may even be useful in the treatment of AIDS to stop the spread of HIV. It has no major side effects, except for possible allergic reactions.
Other plant proteases include papain (from the papaya), actinidin (from the kiwi fruit), and ficin (from the fig). These proteases may induce a prickly sensation in the mouth when consumed.
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