Chilli peppers, capsaicin from

Synthesis The synthesis of capsaicin is shown below (Gannett et al., 1988). For clinical use capsaicin is isolated from chilli pepper (Capsicum annum). 

Capsaicin is the major pungent component of Oleoresin Capsicum (OC), commonly known as pepper spray. OC is extracted from dried ripe chilli peppers and is a variable mixture of many compounds. Related irritants (capsaici-noids) present in the mixture include dihydrocap-saicin, nordihydrocapsaicin, homocapsaicin, ho-modihydrocapsaicin and nonivamide. The latter is used as a synthetic substitute for pepper spray. 

Source and Composition. OC is an oily reddish-brown extract of pepper plants of the genus Capsicum, principally from Capsicum an-nuum and Capsicum frutescens. Depending on the variety of the chilli pepper, OC contains from 0.01 to 1.0% capsaicinoids on a dry mass basis. The extract is a complex mixture of fat-soluble phenols (capsaicinoids), some of which are listed in Table 4. The composition of OC is highly variable and depends on factors such as the conditions of extraction, maturity of the fruit and environmental conditions in which the Capsicum plants were grown. Thus, the capsaicinoid content of extracts used in pepper spray varies between manufacturers (1.2-12.6% Smith and Stopford, 1999). Capsaicin and dihydrocapsaicin make up to 80-90% of the total capsaicinoids in OC extract. 

A number of receptors (nociceptors) located on vagal afferent sensory airway nerves are responsive to a variety of noxious stimuli (chemical and mechanical) known to induce cough. In particular, the rapidly adapting receptor present on myelinated A5-type nerves, which appears polymodal (responding to both chemical and mechanical stimuli) and the small umnyelinated C-libres, sensitive to the chemical capsaicin, the tussive extract from hot chilli peppers, are widely believed to... 

Various topical agents have been tested. Capsaicin is an alkaloid and a main ingredient in chilli peppers, and is available in a cream for topical use. This neurotoxin depletes substance P from the terminals of unmyelinated C-fibres. Substance P is considered the primary neurotransmitter of pain from the periphery to the CNS. Data suggest that Capsacain application produces degeneration followed by reinnervation of epidermal nerve fibres. This in combination with inconsistent results from clinical trials as regards its efficacy for treatment of painful diabetic neuropathy has resulted in limitation of its use [37],... 

Due to safety/toxicology concerns, some substances should be restricted not only when added as such (for which reason they appear in Annex III Part A) but also when they are naturally present in avorings and food ingredients with avoring properties (for which reason they appear in Annex III Part B). Others (e.g., capsaicin) are only restricted when added as such (as chemically de ned substance ) and appear in Annex IB Part A but not when naturally present (hence they do not appear in Annex III Part B). One of the reasons could be that the use of natural sources in which capsaicin is present (e.g., chilli peppers—Capsicum) is self-limiting (at least for consumers in the EU), and setting limits for the use of peppers would be extremely dif cult from an implementation point of view and for control authorities (to check the maximum levels). An opinion on the safety of capsaicin was published by the SCF in 2002 [18]. 

The pungency of chilli is measured in multiples of 100 units, from the bell pepper at zero Scoville units to the incendiary Habanero at 300,000 Scoville units. One part of chilli heat per 1,000,000 drops of water rates as only 1.5 Scoville units. The substance that makes a chilli so hot is capsaicin. Pure capsaicin rates over 15,000,000 Scoville units The Red Savina Habanero has been tested at over 577,000 Scoville units (Padilla and Yahia, 1998). Tiwari et al. (2005) identified the hottest chilli variety in the world. A special variety of chilli, Nagarhari, grown in Tezpur (Assam) has been found to possess a pungency of... 

Also knovm as OC (from Oleoresin capsicum), pepper spray produces significant eye irritation with watering, pain and temporary bUndness. It is used as a crowd control agent and for personal defence. The active ingredient in pepper spray is capsaicin, which is a chemical derived from plants in the Capsicum genus, including chillies. 

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