| Description |
Flavouring ingredient. Pungent principle of various Capsicum subspecies (Solanaceae)_x000D_
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Capsaicin (pronounced /kæp?se??s?n/) (8-methyl-N-vanillyl-6-nonenamide, (CH3)2CHCH=CH(CH2)4CONHCH2C6H3-4-(OH)-3-(OCH3)) is the active component of chili peppers, which are plants belonging to the genus Capsicum. It is an irritant for mammals, including humans, and produces a sensation of burning in any tissue with which it comes into contact. Capsaicin and several related compounds are called capsaicinoids and are produced as a secondary metabolite by chili peppers, probably as deterrents against certain herbivores and fungi. Pure capsaicin is a hydrophobic, colorless, odorless, crystalline to waxy compound.; Capsaicin is a banned substance in equestrian sports because of its hypersensitizing and pain relieving properties. At the show jumping events of the 2008 Summer Olympics, four horses tested positive for the substance, resulting in disqualification.; Capsaicin is a highly irritant material requiring proper protective goggles, respirators, and proper hazardous material handling procedures. It is hazardous in cases of skin contact (irritant, sensitizer), of eye contact (irritant), of ingestion, of inhalation (lung irritant, lung sensitizer). Severe over-exposure to pure capsaicin can result in death; the lethal dose (LD50 in mice) is 47.2 mg/kg. Numerous other adverse health effects can occur in mammals.; Capsaicin is identified as the primary pungent principle in Capsicum fruits. Hot chili peppers that belong to the plant genus Capsicum (family Solanaceae) are among the most heavily consumed spices throughout the world. The capsaicin content of green and red peppers ranges from 0.1 to 1%. Capsaicin evokes numerous biological effects and thus has been the target of extensive., investigations since its initial identification in 1919. One of the most recognized physiological properties of capsaicin is its selective effects on the peripheral part of the sensory nervous system, particularly on the primary afferent neurons. The compound is known to deplete the neurotransmitter of painful impulses known as substance P from the sensory nerve terminals, which provides a rationale for its use as a versatile experimental tool for studying pain mechanisms and also for pharmacotherapy to treat some peripheral painful states, such as rheumatoid arthritis, post-herpetic neuralgia, post-mastectomy pain syndrome and diabetic neuropathy. Considering the frequent consumption of capsaicin as a food additive and its current therapeutic application, correct assessment of any harmful effects of this compound is important from the public health standpoint. Ingestion of large amounts of capsaicin has been reported to cause histopathological and biochemical changes, including erosion of gastric mucosa and hepatic necrosis. However, there are contradictory data on the mutagenicity of capsaicin. A recent epidemiological study conducted in Mexico revealed that consumers of chili pepper were at higher risk for gastric cancer than non-consumers. However, it remains unclear whether capsaicin present in hot chili pepper is a major causative factor in the aetiology of gastric cancer in humans. A growing number of recent studies have focused on anticarcinogenic or antimutagenic phytochemicals, particularly those included in human diet. In summary, capsaicin has dual effects on chemically induced carcinogenesis and mutagenesis. Although a minute amount of capsaicin displays few or no deleterious effects, heavy ingestion of the compound has been associated with necrosis, ulceration and even carcinogenesis. Capsaicin is considered to be metabolized by cytochrome P-450-dependent mixed-function oxidases to reactive species. (PMID: 8621114); Prolonged activation of these neurons by capsaicin depletes presynaptic substance P, one of the body's neurotransmitters for pain and heat. Neurons that do not contain TRPV1 are unaffected. This causes extended numbness following surgery, and the patient does not feel pain as the capsaicin is applied under anesthesia.; The burning and painful sensations associated with capsaicin result from its chemical interaction with sensory neurons. Capsaicin, as a member of the vanilloid family, binds to a receptor called the vanilloid receptor subtype 1 (VR1). First cloned in 1997, VR1 is an ion channel-type receptor. VR1, which can also be stimulated with heat and physical abrasion, permits cations to pass through the cell membrane and into the cell when activated. The resulting depolarization of the neuron stimulates it to signal the brain. By binding to the VR1 receptor, the capsaicin molecule produces the same sensation that excessive heat or abrasive damage would cause, explaining why the spiciness of capsaicin is described as a burning sensation.; The research team led by David Julius of UCSF showed in 1997 that capsaicin selectively binds to a protein known as TRPV1 that resides on the membranes of pain and heat sensing neurons. TRPV1 is a heat activated calcium channel, which opens between 37 and 45 °C. When capsaicin binds to TRPV1, it causes the channel to open below 37 °C (normal human body temperature), which is why capsaicin is linked to the sensation of heat. Capsaicin is found in many foods, some of which are pepper (c. annuum), red bell pepper, green bell pepper, and orange bell pepper. |
