Analysis by HPLC and LC/MS of Pungent Piperamides in Commercial Black, White, Green, and Red Whole and Ground Peppercorns

• Published in: Journal of agricultural and food chemistry Vol. 56; no. 9; pp. 3028 - 3036
• Main Authors: Friedman, Mendel, Levin, Carol E, Lee, Seung-Un, Lee, Jin-Shik, Ohnisi-Kameyama, Mayumi, Kozukue, Nobuyuki
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 14.05.2008
• Subjects: alkaloids; Alkaloids - analysis; Amides - analysis; Benzodioxoles - analysis; Bioactive Constituents; Biological and medical sciences; black pepper; black peppercorns; Chromatography, High Pressure Liquid; Dioxolanes - analysis; food analysis; food chemistry; Food industries; Fruit and vegetable industries; Fundamental and applied biological sciences. Psychology; green pepper; green peppercorns; high performance liquid chromatography; HPLC; LC-MS; liquid chromatography; Mass Spectrometry; Piper nigrum; Piper nigrum - chemistry; piperamides; Piperanine; piperdardine; piperettine; Piperidines - analysis; piperine; piperines; piperlonguminine; Polyunsaturated Alkamides - analysis; red pepper; red peppercorns; secondary metabolites; white pepper; white peppercorns; piperettine; red pepper; LC-MS; white pepper; piperine; piperdardine; green pepper; black pepper; piperlonguminine; HPLC; Piperanine; Vegetables; Pepper; HPLC chromatography; Bell pepper; Liquid chromatography; Piperamide; Red; Piperine; Green
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/jf703711z

Pepper plants accumulate pungent bioactive alkaloids called piperamides. To facilitate studies in this area, high-performance liquid chromatography (HPLC) and liquid chromatography/mass spectrometry methods were developed and used to measure the following piperamides in 10 commercial whole (peppercorns) and in 10 ground, black, white, green, and red peppers: piperanine, piperdardine, piperine, piperlonguminine, and piperettine. Structural identification of individual compounds in extracts was performed by associating the HPLC peak of each compound with the corresponding mass spectrum. The piperanine content of the peppers (in mg/g piperine equivalents) ranged from 0.3 for the ground white pepper to 1.4 in black peppercorns. The corresponding range for piperdardine was from 0.0 for seven samples to 1.8 in black peppercorns; for four isomeric piperines, from 0.7 for red to 129 in green peppercorns; for piperlonguminine, from 0.0 in red peppercorns to 1.0 in black peppercorns; and for piperyline, from 0.9 in ground black pepper to 5.9 for red peppercorn. Four well-separated stereoisomeric forms of piperettine with the same molecular weight were present in 19 peppers. The sums of the piperamides ranged from 6.6 for red to 153 for green peppercorns. In contrast to large differences in absolute concentrations among the peppers, the ratios of piperines to total piperamide were quite narrow, ranging from 0.76 for black to 0.90 for white peppercorns, with an average value of 0.84 ± 0.04 (n = 19). Thus, on average, the total piperamide content of the peppers consists of 84% piperines and 16% other piperamides. These results demonstrate the utility of the described extraction and analytical methods used to determine the wide-ranging individual and total piperamide contents of widely consumed peppers.