Source
Instituto de Fermentaciones Industriales, Spanish National Research Council, Juan de la Cierva 3, 28006, Madrid, Spain. ifiht16@ifi.csic.es
Abstract
Tetrahydro-beta-carbolines (THbetaCs), potential neuroactive alkaloids, were found in chocolate and cocoa. 6-Hydroxy-1-methyl-1,2, 3,4-tetrahydro-beta-carboline (6OHMTHbetaC), 1,2,3, 4-tetrahydro-beta-carboline-3-carboxylic acid (THCA), 1-methyl-1,2,3, 4-tetrahydro-beta-carboline-3-carboxylic acid (MTCA) in both diastereoisomers (1S,3S and 1R,3S), and 1-methyl-1,2,3, 4-tetrahydro-beta-carboline (MTHbetaC), besides serotonin and tryptamine biogenic amines, were identified and quantified in dark chocolate, milk chocolate, cocoa, and chocolate-containing cereals by RP-HPLC-fluorescence and HPLC-MS. For each THbetaC, the concentration ranges were determined: 6OHMTHbetaC (0.16-3.92 microg/g), THCA (0.01-0.85 microg/g), 1S,3S-MTCA (0.35-2 microg/g), 1R,3S-MTCA (0.14-0.88 microg/g), and MTHbetaC (nd-0.21 microg/g). The highest content was generally found in chocolates and cocoas, but cereals containing chocolate also showed an appreciable amount of THbetaCs. The possible biological implications of this novel group of alkaloids in chocolate are discussed.