Formation of Tetrahydro-β-carbolines and β-Carbolines during the Reaction of l-Tryptophan with d-Glucose

Abstract

The reaction of L-tryptophan (Trp) with D-glucose under conditions that can occur during food processing and preparation was studied by high-performance liquid chromatography with diode array detection (HPLC/DAD). Besides the well-established glucose-tryptophan Amadori product (AP), (1R,3S)-1-(D-gluco-1,2,3,4,5-pentahydroxypentyl)-1,2,3, 4-tetrahydro-beta-carboline-3-carboxylic acid (PHP-THbetaC) was identified as an important product of this reaction. For preparation, PHP-THbetaC was obtained in high yields when Trp and D-glucose were reacted under strongly acidic conditions after heating in methanol. At elevated reaction temperatures (150 degrees C) 1-acetyl-beta-carboline (acetyl-betaC), was detected in significant concentrations. The mixtures were heated under variations of reaction time and temperature, and AP, PHP-THbetaC, and acetyl-betaC were quantified. In the presence of air oxygen or mild, food relevant oxidants, such as L-dehydroascorbic acid, PHP-THbetaC was readily oxidized to a product that was identified as the previously unknown 1-(D-gluco-1,2,3,4,5-pentahydroxypentyl)-beta-carboline (PHP-betaC). Formation of PHP-THbetaC and PHP-betaC in foodstuffs would deserve particular interest because multiple physiological activity of THbetaC and betaC derivatives has been shown previously.

The intermolecular Pictet-Spengler condensation with chiral carbonyl derivatives in the stereoselective syntheses of optically-active isoquinoline and indole alkaloids

“…A couple of sections are also dedicated each to the use of complex synthetic as well as naturally occurring aldehydes, such as secologanin and ircinal A, as components in the Pictet-Spengler cyclocondensation. alcoholic beverages such as beer, wine and sherry) in the µg/L to mg/L range, Herraiz and Galisteo found that the cis/trans ratio of THBC formed was different in grape juice, pineapple juice and tomato juice, the trans isomer prevailing only in the latter, while Rönner and coworkers 39 investigated the oxidative decarboxylation of 1-(D-gluco-1,2,3,4,5-penta hydroxypentyl)-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid which resulted in formation of 1-(D-gluco-1,2,3,4,5-pentahydroxypentyl)-β-carboline (11→12 …”

Exposure to β-carbolines norharman and harman

“…Originally, it was believed that the carbolines are formed only at high temperatures and have been referred to as protein pyrolysis products [4]. Tryptophan was identified as precursor and glucose is enhancing norharman formation [66,67]. In an aqueous model systems containing creatine, glucose and various single amino acids norharman and harman were formed in mixtures containing isoleucine, arginine, phenylalanine and tryptophane, while tyrosione afforded norharman upon heating at 180 • C for 10 min [68].…”

Influence of β-Carboline Produced from Glucose and Tryptophan on Protein Synthesis of Chicken Embryo Myoblasts

“…The ionization method was FAB. The structure of PHP-THβC was also examined by 1 H-NMR spectroscopy (Nishimagi, Kawashima, Kajita, Namauo, Ogawa, Muraoka, Fujimura and Kita, unpublished results) and NMR data was compared to the literatures (Röper et al, 1983;Rönner et al, 2000).…”