Topic
Theobromine
About: Theobromine is a research topic. Over the lifetime, 1137 publications have been published within this topic receiving 29723 citations. The topic is also known as: 3,7-Dimethylxanthine & Theobromin.
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TL;DR: Theobromine, theophylline, and caffeine are determined simultaneously by a rapid and selective reversed-phase high-performance liquid chromatography (HPLC) method with UV detection in by-products of cupuacu and cacao seeds.
Abstract: Theobromine, theophylline, and caffeine are determined simultaneously by a rapid and selective reversed-phase high-performance liquid chromatography (HPLC) method with UV detection in by-products of cupuacu and cacao seeds. The determination is carried out in the raw and roasted ground cupuacu seeds and in the corresponding powders obtained after pressure treatment. The by-products of both cupuacu seeds and cacao seeds are obtained under the same technological conditions. The HPLC method uses isocratic elution with a mobile phase of methanol-water-acetic acid (80:19:1) (v/v) at a flow rate of 1 mL/min and UV absorbance detection at 275 nm. Total elution time for these analytes is less than 10 min, and the detection limit for all analytes is 0.1 mg/g. The amounts of theobromine and caffeine found in all the cupuacu samples are one or more orders of magnitude lower than those from cacao. Theophylline is found in all cacao samples except for the roasted ground paste, and it is only found in the roasted ground paste in the cupuacu samples.
33 citations
TL;DR: It was demonstrated that the altered endocrine environment caused by caffeine consumption could be equated with a stress-like pattern of response and suggested that high steroid levels may in the long-term cause an altered hepatic clearance pattern affecting both steroid metabolism and caffeine elimination.
Abstract: It was demonstrated that the altered endocrine environment caused by caffeine consumption could be equated with a stress-like pattern of response. A single acute treatment with caffeine (30 or 60 mg/kg) to male rats approximately 85 days old caused plasma concentrations of corticosterone, progesterone, testosterone and Na+ to rise significantly above control values. These changes were evident 3 min after caffeine administration and were maintained for 1-4 h before returning to normal. In animals exposed to daily chronic caffeine treatment for 10 days or more the levels of progesterone fell and Na+ rose significantly compared with control values at 24 h after administration. Following a single treatment of 30 mg/kg, caffeine was detected in blood plasma after 3 min, and reached peak levels by 1 h. After 24 h, less than 2% of the peak levels of caffeine remained. Metabolites of caffeine were detectable within 6 min and reached their peak levels 4 and 12 h later for theophylline and theobromine respectively. It is suggested that high steroid levels may in the long-term cause an altered hepatic clearance pattern affecting both steroid metabolism and caffeine elimination. A preliminary study of the morphology of livers from males chronically exposed to caffeine revealed that the hepatic cells lost cytoplasmic matrix, and that the sinusoids did not show up as clear spaces, compared with those in the controls.
33 citations
TL;DR: Caffeine and the dimethylxanthines cause breakage at 750 mug/ml, with caffeine the most, and paraxanthine the least clastogenic.
Abstract: The effect of caffeine (1,3,7-trimethylxanthine), theophylline (1,3-dimethyl-xanthine), theobromine (3,7-dimethylxanthine), paraxanthine (1,7-dimethylxanthine) 1-methylxanthine, 3-methylxanthine, and 7-methylxanthine added at the 48th h on the chromosomes of human lymphocytes in 72-h cultures has been investigated. Caffeine and the dimethylxanthines cause breakage at 750 μg/ml, with caffeine the most, and paraxanthine the least clastogenic. 1-methylxanthine and dimethylxanthines with a methyl group in the 1-position are the most effctive in depressing mitotic indices. No chromosome damage was exhibited by the monomethylxanthines.
33 citations
TL;DR: Synchronous growth studies indicated that a particular growth stage of the organisms was most susceptible to the synergistic effect, and the mutation studied was that of Escherichia coli B/r to high-level streptomycin resistance.
Abstract: Doneson, Ira N. (University of Kansas, Lawrence), and Delbert M. Shankel. Mutational synergism between radiations and methylalted purines in Escherichia coli. J. Bacteriol. 87:61-67. 1964.-A synergistic mutational effect was demonstrated between low doses of ultraviolet light and the methylated purines caffeine, theophylline, and theobromine. Caffeine produced the greatest effect and theobromine the least effect. The magnitude of the synergism was inversely related to the ultraviolet dosage. A large percentage of the synergistic effect could be "photoprevented" by exposure of the ultraviolet-treated cells to white light prior to exposure to the analogues. The consequence of the combined treatment occurred only when the chemical treatment followed the ultraviolet treatment. Furthermore, it was necessary to administer the chemical treatment soon after the ultraviolet treatment or the mutants were "lost." When cells were treated with low dosages of ultraviolet light and of X irradiation (X ray), the result was merely additive, and combinations of X ray and chemical treatment yielded no synergism. Synchronous growth studies indicated that a particular growth stage of the organisms was most susceptible to the synergistic effect. The mutation studied was that of Escherichia coli B/r to high-level streptomycin resistance.
32 citations
Journal Article•
32 citations