Capsaicinoids analysis

Although most consumers appreciate the fieriness of chile, capsaicinoids are not perceived through odor or taste receptors but through the nociceptive pain receptors described earlier. The compounds in chile fruit that create the flavor and aroma are produced in the fruit wall. Buttery et al. [90] generated vacuum steam distilled oil from green bell pepper macerate, with well over 40 peaks on subsequent GC/MS analysis. Of these peaks, the major flavor compound associated with bell pepper aroma was 2-methoxy-3-isobutylpyrazine (Fig. 8.1). They also reported several monoterpenoids in abundance, limonene, trans- 3-ocimene, and linalool as well as other aliphatic aldehydes and ketones. The flavor composition of dried red bell pepper powder (sweet paprika) extracted with ether identified 44 key peaks by GC/MS [91]. In these dried samples the key compounds were P-ionone and several furanones. The post-harvest processing and the different fruit maturities as well as possible varietal differences are all causes for the different aromatic profiles. 

Blum E, Mazourek M, O Connell MA, Curry J, Thorup T, Liu K, Jahn MM, Paran I (2003) Molecular mapping of capsaiciniod biosynthesis genes and QTL analysis for capsaicinoid content in Capsicum. Theor Appl Genet 108 79-86... 

Analysis of chemical constituents in fruits of red pepper (cv. Bugang) revealed five natural capsaicinoids. They were capsaicin, nordihydrocapsaicin, dihydrocapsaicin, vanillyl decanamide and homodihydrocap-saicin. The concentration of total capsaicinoids in fruits was 5.4mg/100g FW. Eleven carotenoids were identified, with a total concentration of 65 mg/100g FW. The con-... 

Blum, E., Mazourek, M., O Connell, M., Curry, J., Thorup, T., Liu, K., Jahn, M. and Paran, I. (2004) Molecular mapping of capsaicinoid biosynthesis genes and quantitative trait loci analysis for capsaicinoid content in Capsicum. Theoritical and Applied Genetics 108(1), 79-86. 

Reilly, C.A., Crouch, D.J. and Yost, G.S. (2001) Quantitative analysis of capsaicinoids in fresh peppers, oleoresin capsicum and pepper spray products. Journal of Forensic Sciences 46(3), 502-509. 

Since hot pepper is important for the food and the pharmaceutical industries, a range of different methods have been developed for the analysis of capsaicinoids in plant material and finished products. The separation of CPS (la) and nonivamide (11) is especially challenging, since these compounds have similar behavior in many chromatographic conditions. Since synthetic nonivamide is the most common adulterant of capsicum oleoresin, various strategies have been suggested to overcome this problem. Capillary GC does not require previous derivatization of capsaicinoids, but its separatory power seems lower than that of HPLC, currently the most popular technique for the quantization of capsaicinoids. GC is, however, the method of choice for the analysis of the acyl moieties of capsaicinoids as methyl esters. These can be directly produced from capsaicinoids by oxidative N-dealkylation with DDQ (2,3-dichloro-5,6-dicyanobenzoquinone), followed by alcoholysis of the resulting amides with methanol in the presence of an acidic resin (Scheme 4.4) [41]. 

Combination of UV-visible spectrophotometric wavelength scans and chemometiic (PCA) analysis seems to be a simple and fast way to prospect plant extracts. This analytical strategy revealed to be fruitful for discrimination of habanero peppers according to their content of capsaicinoids, substances responsible for the pungency of their fruits (Davis et... 

Stage that requires high efficiency as well as speed, due to the complexity of the sample matrix, and hence it is particularly challenging to achieve the goals. Therefore, the development of a rapid, sensitive, and reproducible method has been required for separation and determination of capsaicinoid compounds. The addition of ultraperformance liquid chromatography-mass spectrometry (UPLC-MS) method fulfilled these aforementioned demands and showed some complementary advantages to the conventional HPLC-MS, u-HPLC methods in terms of shorter analysis times, low sample volume, and much improved sensitivity [71]. Therefore, nowadays this UPLC-MS technique is routinely performed in pharmaceutical industries and related contract research institutes, laboratories concerned with biochemistry, biotechnology, environmental analysis, natural product research, and several other research fields. The UPLC-MS method has successfully been applied for the determination of n-DHC, C, DHC, h-C, and h-DHC present in the varieties of hot peppers [71]. 

MaiUard, M., Giampaoli, P, and Richard, H. M. J. 1997. Analysis of eleven capsaicinoids by reversed-phase high performance liquid chromatography. Flav. Frag. J. 12 409-113. 

The book begins with an overview of the history, principles, and advancement of chromatography. It discusses the use of UHPLC techniques in food metabolomics, approaches for analysis of foodborne carcinogens, and details of UPLC-MS techniques used for the separation and determination of capsaicinoids. Chapters describe the analysis of contaminants in food, including pesticides, aflatoxin, per-fluorochemicals, and acrylamide, as well as potentially carcinogenic heterocyclic amines in cooked foods. 

Quantitative analysis of capsaicinoids in peppers and pepper spray products)... 

An exhaustive analysis of the structural implications of capsaicinoids on their metabolism by P450 enzymes and how they contribute to both detoxification and bioactivation processes in humans has been proposed. CycUzation, dehydrogenation to afford the terminal diene and imides, oxidatiOTi at the end of the carbon chain to render primary and tertiary alcohols, and demethylation and aromatic hydroxylation, are typical reactions in these processes, yielding metabolites with limited pharmacological and toxicological effects via reduction in their affinity for TRPVl [148]. 

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