Capsaicin is also the active ingredient in riot control and personal defense chemical agents. When the spray comes in contact with , especially or , it is very painful, and breathing small particles of it as it disperses can cause breathing difficulty, which serves to discourage assailants. Refer to the for a comparison of pepper spray to other sources of capsaicin.
Genetic and molecular approaches have also contributed to the knowledge of this biosynthetic pathway; however, more studies are necessary for a better understanding of the regulatory process that accounts for different accumulation levels of capsaicinoids in chili pepper fruits.">
Capsaicin is believed to be synthesized in the interlocular septa of chili peppers by addition of a branched-chain to vanillylamine. Biosynthesis depends on the gene AT3, which resides at the pun1 , and which encodes a putative .
Fresh red peppers were purchased from 74 cultivated samples in the major red pepper production region (Gochang, Koesan, Imsil, Andong, Youngyang province) in 2009. The samples were de-stemmed, cleaned, cut and dried. Seeds were then separated out of the sample followed by milling. To homogenize the particle size of periscarp, all samples were ground to powder using a roll mill, and the particle size of each sample was controlled to below 1.0 mm using a To-Tap sieve shaker (Cheonggesa CG-213, Seoul, Korea). Fructose, glucose, sucrose, capsaicin and dihydrocapsaicin were purchased from Sigma Aldrich Co. (St. Louis, MO, USA). Solvents used for analyses were of HPLC grade and purchased from Fisher Scientific Korea (Seoul, Korea).
Capsaicinoids are synthesized through the convergence of two biosynthetic pathways: the phenylpropanoid and the branched-chain fatty acid pathways, which provide the precursors phenylalanine, and valine or leucine, respectively.
The establishment of cDNA libraries and comparative gene expression studies in pungent and non-pungent chili pepper fruits has identified candidate genes possibly involved in capsaicinoid biosynthesis.
Genetic and molecular approaches have also contributed to the knowledge of this biosynthetic pathway; however, more studies are necessary for a better understanding of the regulatory process that accounts for different accumulation levels of capsaicinoids in chili pepper fruits.
The total free sugar content of the red pepper samples ranged from 16.76 to 29.92%. In particular, the glucose, fructose and sucrose contents were 5.60~11.20%, 8.91 ~16.89% and 1.78~2.97%, respectively. The free sugar-related sweetness of red pepper is a very important quality factor that affects consumer acceptability (). The results were consistent with previous studies, which reported that the Korean red pepper had a free sugar content of about 20% ().