**5. Mechanism of action**

The mechanism of analgesia that capsaicinoids produce is probably due to their counter-intuitive effect [35]. Capsaicinoids applied directly to the skin or injected by intradermal route induce both hyperalgesia and allodynia. Capsaicin causes excitation of certain subsets of dorsal root ganglia giving rise to the stimulation of thin myelinated A-delta and unmyelinated C fibers. These nerve fibers are specific for the transmission of pain signals and therefore seem to be sensitive to vanilloids such as capsaicin, which blocks particularly the transmission of noxious stimuli [36]. Due to the blockade of terminal peripheral nerves, capsaicin inhibits the release of several pro-inflammatory neuropeptides such as Substance P, calcitonin gene-related peptide, and somatostatin [37]. The prolonged stimulation of neurons by capsaicin may deplete the nerve's ability to release the presynaptic neuropeptides, particularly Substance P. The ability of capsaicin to desensitize nociceptors is the main reason behind its therapeutic efficacy [38]. It has also been attributed that capsaicin could modulate the amount of specific neurotransmitter called Substance P, associated with the feeling of pain and thus helps alleviate pain externally [39]. Research findings claim that pure capsaicin could possess similar efficacy in treating joint and muscle pain induced in rheumatism, arthritis, ankylosing spondylitis, and

Capsicum

**Figure 2.**

**Table 2.**

*Chemical structures of capsaicinoids.*

**100**

**4. Medicinal properties**

*Jolokia* is comparable with that of the Red Savina Habanero of Mexico in terms of Scoville Heat Units (SHUs) [17]. The pungency of *Bhut Jolokia* was recorded 855,000 SHU, while it was 577,000 SHU for Red Savina Habanero. Studies at the New Mexico State University also reported that *Bhut Jolokia* possessed 1,001,304 SHUs, whereas Red Savina had 248,556 SHUs [18]. In September 2006, the *Bhut Jolokia* was officially recognized as the world's hottest *Capsicum* variety measuring over 1,000,000 SHUs according to the Guinness Book of World Records [19].

**Species** *Capsicum* **variety Capsaicinoids content (%)**

*Maam Jolokia* 1.38 *Totta Bias* 0.25

*Capsicum annum Jati Jolokia* 0.51 *Capsicum chinense Bhut Jolokia* 2.45 *Capsicum frutescens Dhan Jolokia* 2.14

*Capsicum baccatum Ohm Jolokia* 0.67 *Capsicum pubescens Bhikue Jolokia* 0.92

*Capsaicinoids content (%) of indigenous* Capsicum *varieties of India [15, 16].*

Apart from wide commercial applications of *Capsicum* pods or chili pepper as culinary spice and also their use in various food products such as seasoning blends and in the canning industry, *Capsicum* also possess a diverse range of medicinal and/or pharmacological potential. In medicine, capsaicinoids, the active ingredients of *Capsicum* pods, have been used for the treatment of gastritis, arthritis, toothache, musculoskeletal and neuropathic pain, chronic indigestion, other pharmacological disorders and also microbial infections [20–22]. Capsaicinoids have been reported to exhibit a diverse range of biological effectiveness such as antioxidant, analgesic,

fibromyalgia. Further, clinical reports suggest that capsaicin increases not only the secretion of saliva and gastric juice, but also improves the blood flow in the lining of the gastrointestinal tract, which might be beneficial in gastrointestinal abnormalities [40, 41].
