Showing papers on "Theobromine published in 2008"

Simultaneous HPLC Determination of Caffeine, Theobromine, and Theophylline in Food, Drinks, and Herbal Products

Abstract: A rapid and selective high-performance liquid chromatographic (HPLC) method is developed for the separation and determination of caffeine, theobromine, and theophylline. The chromatography is performed on a Zorbax Eclipse XDB-C8 column (4.6x150 mm i.d., 5-microm particle size) at 25 degrees C, with a mobile phase of water-THF (0.1% THF in water, pH 8)-acetonitrile (90:10, v/v). The flow rate is 0.8 mL/min, and detection is by UV at 273 nm. This method permits the simultaneous determination of caffeine, theobromine, and theophylline in food, drinks, and herbal products with detection limits of 0.07-0.2 mg/L and recoveries of 100.20-100.42%. Correlation coefficients, for the calibration curves in the linear range of 0.2-100 mg/L, are greater than 0.9999 for all compounds. The within- and between-day precision is determined for both retention times and peak area. The data suggests that the proposed HPLC method can be used for routine quality control of food, drinks, and herbal products.

A Novel Caffeine Dehydrogenase in Pseudomonas sp. Strain CBB1 Oxidizes Caffeine to Trimethyluric Acid

Abstract: A unique heterotrimeric caffeine dehydrogenase was purified from Pseudomonas sp. strain CBB1. This enzyme oxidized caffeine to trimethyluric acid stoichiometrically and hydrolytically, without producing hydrogen peroxide. The enzyme was not NAD(P)+ dependent; coenzyme Q0 was the preferred electron acceptor. The enzyme was specific for caffeine and theobromine and showed no activity with xanthine.

Increases in cerebrospinal fluid caffeine concentration are associated with favorable outcome after severe traumatic brain injury in humans

Abstract: Caffeine, the most widely consumed psychoactive drug and a weak adenosine receptor antagonist, can be neuroprotective or neurotoxic depending on the experimental model or neurologic disorder. However, its contribution to pathophysiology and outcome in traumatic brain injury (TBI) in humans is undefined. We assessed serial cerebrospinal fluid (CSF) concentrations of caffeine and its metabolites (theobromine, paraxanthine, and theophylline) by high-pressure liquid chromatography/ultraviolet in 97 ventricular CSF samples from an established bank, from 30 adults with severe TBI. We prospectively selected a threshold caffeine level of > or = 1 micromol/L (194 ng/mL) as clinically significant. Demographics, Glasgow Coma Scale (GCS) score, admission blood alcohol level, and 6-month dichotomized Glasgow Outcome Scale (GOS) score were assessed. Mean time from injury to initial CSF sampling was 10.77+/-3.13 h. On initial sampling, caffeine was detected in 24 of 30 patients, and the threshold was achieved in 9 patients. Favorable GOS was seen more often in patients with CSF caffeine concentration > or = versus or = versus < the threshold. Increases in CSF concentrations of the caffeine metabolites theobromine and paraxanthine were also associated with favorable outcome (P=0.018 and 0.056, respectively). Caffeine and its metabolites are commonly detected in CSF in patients with severe TBI and in an exploratory assessment are associated with favorable outcome. We speculate that caffeine may be neuroprotective by long-term upregulation of adenosine A1 receptors or acute inhibition of A2a receptors.

Chocolate consumption in pregnancy and reduced likelihood of preeclampsia.

Abstract: Recent research suggests that chocolate, particularly dark chocolate, may benefit cardiovascular health. Chocolate contains over 600 chemicals including flavanoids, magnesium, and theobromine. Flavanoids (including flavanols, flavones, flavanones, and others) are potent antioxidants capable of inducing nitric oxide-dependent vasodilation, as well as having antiplatelet and anti-inflammatory effects.1,2 Magnesium deficits have been linked to hypertension, and other cardiovascular disease.3,4 The methylxanthine theobromine is present in very high quantities, with dark chocolate containing the most.5 The primary pharmacologic effects of theobromine include diuresis, myocardial stimulation, vasodilation, and smooth muscle relaxation,6 and it has been used to treat hypertension, angina, and atherosclerosis.7 Theobromine is widely consumed in the form of chocolate and cocoa products, and although theobromine is one of the 3 primary metabolites of caffeine, it accounts for only about 12% of total metabolized caffeine, compared with 70% to 80% for paraxanthine.6 Thus, theobromine is a useful, specific biomarker for chocolate consumption. In addition, theobromine, along with the other methylxanthines, freely crosses the placental barrier in pregnancy. Preeclampsia is a serious maternal complication of pregnancy that affects 3% to 8% of pregnancies.8 Preeclampsia shares many characteristics and risk factors of cardiovascular disease, including endothelial dysfunction, oxidative stress, hypertension, insulin resistance, and hypertriglyceridemia.9 Cardiovascular manifestations of preeclampsia include changes in vascular reactivity, hypertriglyceridemia, endothelial dysfunction, and hypertension.8,10,11 Women with preeclampsia may also be at increased risk of cardiovascular disease and metabolic disturbances in the years following pregnancy.12–16 We investigate whether chocolate consumption, measured by self-reported maternal intake and fetal cord serum concentrations of theobromine, is associated with preeclampsia.

Simultaneous Determination of Theobromine, (+)-Catechin, Caffeine, and (−)-Epicatechin in Standard Reference Material Baking Chocolate 2384, Cocoa, Cocoa Beans, and Cocoa Butter

Abstract: A reverse-phase liquid chromatography analysis is used to access the quantity of theobromine, (+)-catechin, caffeine, and (-)-epicatechin in Standard Reference Material 2384 Baking Chocolate, cocoa, cocoa beans, and cocoa butter using water or a portion of the mobile phase as the extract. The procedure requires minimal sample preparation. Theobromine, (+)-catechin, caffeine, and (-)-epicatechin are detected by UV absorption at 273 nm after separation using a 0.3% acetic acid-methanol gradient (volume fractions) and quantified using external standards. The limit of detection for theobromine, (+)-catechin, caffeine, and (-)-epicatechin averages 0.08, 0.06, 0.06, and 0.06 microg/mL, respectively. The method when applied to Standard Reference Material 2384 Baking Chocolate; baking chocolate reference material yields results that compare to two different, separate procedures. Theobromine ranges from 26000 mg/kg in cocoa to 140 mg/kg in cocoa butter; (+)-catechin from 1800 mg/kg in cocoa to below detection limits of < 32 mg/kg in cocoa butter; caffeine from 2400 mg/kg in cocoa to 400 mg/kg in cocoa butter, and (-)-epicatechin from 3200 mg/kg in cocoa to BDL, < 27 mg/kg, in cocoa butter. The mean recoveries from cocoa are 102.4 +/- 0.6% for theobromine, 100.0 +/- 0.6 for (+)-catechin, 96.2 +/- 2.1 for caffeine, and 106.2 +/- 1.7 for (-)-epicatechin.

Riboflavin-Binding Protein Is a Novel Bitter Inhibitor

Abstract: Riboflavin-binding protein (RBP) from chicken egg, which was recently reported to be a selective sweet inhibitor for protein sweeteners, was also found to be a bitter inhibitor. RBP elicited broadly tuned inhibition of various bitter substances including quinine-HCl, naringin, theobromine, caffeine, glycyl-L-phenylalanine (Gly-Phe), and denatonium benzoate, whereas several other proteins, such as ovalbumin (OVA) and beta-lactoglobulin, were ineffective in reducing bitterness of these same compounds. Both the bitter tastes of quinine and caffeine were reduced following an oral prerinse with RBP. It was found that RBP binds to quinine but not to caffeine, theobromine, naringin, and Gly-Phe. However, the binding of RBP to quinine was probably not responsible for the bitter inhibition because OVA bound to quinine as well as RBP. Based on these results, it is suggested that the bitter inhibitory effect of RBP is the consequence of its ability to interact with taste receptors rather than because it interacts with the bitter tastants themselves. RBP may have practical uses in reducing bitterness of foods and pharmaceuticals. It may also prove a useful tool in studies of mechanisms of bitter taste.

Quantitation of methylxanthinic alkaloids and phenolic compounds in mate (Ilex paraguariensis) and their effects on blood vessel formation in chick embryos.

Abstract: Methylxanthinic alkaloids and phenolic compounds are related to the therapeutic properties of Ilex paraguariensis infusions. Considering the known vascular tropism of xanthines, an aqueous extract (mate) and caffeine were evaluated on blood vessel formation, in connection with the analysis of those secondary metabolites, which was performed in young and mature leaf samples collected in three cultivation systems located in the southern region in Brazil (Santa Catarina State). Samples of young and mature leaves from a monoculture cultivation system (MC) showed the highest content of phenolic compounds (149.68 microg/mL, young leaves; 135.50 microg/mL, mature leaves) and caffeine (young leaves, 148.07 microg/mL; mature leaves, 244.63 microg/mL) as compared to samples from agroforesty (AF) and shaded-native (NT) cultures. Theophylline was not detected in samples by reverse phase-high performance liquid chromatography, and mature leaves showed lower theobromine amounts (11.46 microg/mL). Treatments performed with mate aqueous extract and caffeine (1.03-4.12 microM/disk) in the yolk sac vascular membranes of 2-day-old chick embryos revealed pro-vasculo- and angiogenic properties as well as embryonic growth enhancement. These findings, uncoupled from any detectable embryotoxic effect, suggest a potential therapeutic and/or prophylactic use in cardiovascular disorders for caffeine and related constituents of mate plant extracts, an issue that waits further studies.

Production of a new low-caffeine hybrid coffee and the biochemical mechanism of low caffeine accumulation

Abstract: The GCAs are new tetraploid interspecific hybrids developed in Madagascar from Coffea eugenioides, C. canephora and C. arabica. Selected GCA having genotype UF1023 contained 0.37% DW caffeine and no detectable theobromine in green beans. Low caffeine accumulation in GCA plants is due mainly to the low biosynthetic activity of purine alkaloids, possibly the extremely weak N-methyltransferase reactions in caffeine biosynthesis. No significant catabolic activity of caffeine was found in GCA-UF1023, in common with almost all coffee plants including C. arabica.

Caffeine markedly sensitizes human mesothelioma cell lines to pemetrexed.

Abstract: Pemetrexed is a new generation antifolate approved for the treatment of mesothelioma and non-small cell lung cancer. Caffeine is known to augment radiation or chemotherapeutic drug-induced cell killing. The current study addresses the impact of caffeine on the activity of pemetrexed in mesothelioma cell lines. Caffeine enhanced pemetrexed activity in all four mesothelioma cell lines tested (H2052, H2373, H28 and MSTO-211H). Caffeine sensitized H2052 cells in a dose- and schedule-dependent manner, and was associated with a markedly decreased clonogenic survival. Caffeine sensitization occurred only in cells subjected to pulse, but not continuous, exposure to pemetrexed. Similar pemetrexed sensitization was also observed with the clinically better tolerated caffeine analog, theobromine. Pemetrexed sensitization by caffeine was associated with an increase in pemetrexed-induced phosphorylation of ataxia-telangiectasia-mutated (ATM) and Chk1. These data indicate that caffeine and its analog, theobromine, may be a useful approach to enhance pemetrexed-based chemotherapy.

Comparative effects of theobromine and Cocoa Bean Shell (CBS) extract on the performance, serum constituent profile and physiological parameters in rabbits

Abstract: The effects of theobromine and an extract of cocoa bean shell (CBS) on performance, serum constituent and physiological parameters were compared in rabbits. Synthetic theobromine (300mg/kg) and theobromine from CBS extract (3000mg/kg) were administered through oral gavage for 10 days. Synthetic theobromine and theobromine from CBS caused significant (p 0.05) effect on Na+, K+ and total protein. Synthetic theobromine induced significant (p Keywords : Synthetic theobromine, CBS extract, rabbits Global Journal of Pure and Applied Sciences Vol. 14 (3) 2008: pp. 253-256

Biosynthesis and Catabolism of Purine Alkaloids in Camellia Plants

Abstract: A few Camellia plants accumulate caffeine, theobromine and theacrine. The present article reviews the distribution of purine alkaloids and biosynthetic pathways, including properties and genes of t...

Theobromine production process

Abstract: A process for preparing theobromine by methylating 3-methyl xanthine disodium salt comprises reacting 3-methyl xanthine disodium salt with dimethyl sulfate by using acetone as solvent in the presence of sodium carbonate and acidifying. The present application also provides a process for refining theobromine which comprises dissolving coarse theobromine in liquid alkaline solution, decolorizing, filtering, adding reducing agent in filtrate, and acidifying at 60-80 °C until pH is 5-6, filtering, and drying to obtain theobromine.

Catechins and methylxanthines in twenty-three black tea infusions by hplc : correlations with astringency

Abstract: Simultaneous detection of flavanols [catechin (C), epicatechin (EC), epigallocatechin (EGC), epicatechingallat (ECG), epigallocatechingallate (EGCG)], gallic acid (GA), theogalline, methylxanthines (caffeine, theobromine, theophylline) were performed on 23 black tea infusions. A hypersil-ODS column (4.6 mm I.D. x 250 mm) with methanol: distilled water: formic acid (19.5:80.2:0.3, v:v:v) as a mobile phase was used for optimizing the RP-HPLC separation (R 2 =0.9997). Total flavanols varied from 1.423 to 12.051 mg 100 mg -1 whereas EGCG was the major catechin in all of the infusions (0.356-5.972 mg 100 mg -1 ) (p<0.01). Caffeine levels were high (4.002-8.657 mg 100 mg -1 ) followed by theobromine and theophylline (p<0.01). Black tea contained 0.134-1.392 mg/100 mg of GA, and 0.156-1.241 mg 100 mg -1 of its ester theogalline. An 8-member trained sensory panel judged black tea infusions for astringency. The correlations between the total catechins and astringency (y=1.675+6.631 In X) (R 2 =0.9551) were extremely high at the 95 percent confidence level (X=total catechin, y=astringency) and total interactions on astringency were obtained.

Novel method for producing theobromine with 3_methylxanthine disodium salt methylating

Abstract: The invention provides a new method for preparing a theobromine by a 3-methyl xanthine disodium salt methylation with more production value. The theobromine is prepared by using acetone as a solvent to react with a dimethyl sulfate under the existence of a sodium carbonate and then acidified. The invention uses the acetone as the solvent and decreases the hydrolysis loss of the dimethyl sulfate; the sodium carbonate provides an alkaline condition for the methylation reaction and the Ph value is intermediate. The dimethyl sulfate is dropped to carry out the methylation reaction with the advantages of good selectivity and a yield higher than other methylation technique by more than 10 percent. The acetone is recycled and reused, the reaction is relatively complete and has little caffeine by-product, and the acquired analysis content of theobromine crude product HPLC is larger than 99 percent. The invention is extremely applicable to industrial production.

Simultaneous determination of theanine,catechins and alkaloids in tea by HPLC-PDA

Abstract: One method which could simultaneously determine the main components in tea,such as C,EC,EGC,ECG,EGCG,GCG,caffeine,theobromine,theophylline,theanine and gallic acid,was built by using HPLC-PDA.The method performed with a C18 chromatogram column and gradient elution at column temperature 25℃ and PDA detector at 190 nm and 280 nm.Mobile phase A was 0.05% trifluoroacetic acid and mobile phase B was acetonitrile.The flow rate was 1mL·min-1 and injection volume was 5 μL.The results showed that the calibration curves between peak areas and contents of components in tea were linear within the suitable concentration range.R2 was between 0.9989 and 0.9997,the mean recovery rates were from 96.31% to 103.13%.It is proved that this method is convenient and precise,which could be used for determination of catechins,theanine and alkaloids in tea and tea extracts.

A case-series on chocolate poisoning in four Terrier dogs in Tehran

Abstract: Chocolate poisoning occurs most commonly in dogs, although many species are susceptible. Chocolate toxicosis may result in potentially life-threatening cardiac arrhythmias and CNS dysfunction Contributing factors include indiscriminate eating habits and readily available sources of chocolate. Deaths have also been reported in livestock fed cocoa byproducts and in animals consuming much from cocoa-bean hulls.Chocolate is derived from the roasted seeds of Theobroma cacao.The toxic principles in chocolate are the methylxanthines theobromine & caffeine .Although the concentration of theobromine in chocolate is 3-10 times of caffeine, both constituents contribute to the clinical syndrome seen in chocolate toxicosis.However, in general, the total methylxanthine concentration of dry cocoa powder is 28.5 mg/g unsweetened (baker’s) chocolate is 16 mg/g , semisweet chocolate and sweet dark chocolate is 5.4-5.7 mg/g, and milk chocolate is 2.3 mg/g. White chocolate is an insignificant source of methylxanthines. Cocoa bean hulls contain 9.1 mg/g methylxanthines.The LD50 of caffeine and theobromine are reportedly 100-200 mg/kg, but severe signs and deaths may occur at much lower doses and individual sensitivity to methylxanthines varies. In general, mild signs may be seen in dogs ingesting 20 mg/kg, cardiotoxic effects may be seen at 40-50 mg/kg, and seizures may occur at doses ?60 mg/kg.In the summer of 2007 four(2male&2 female) Terrier dogs were referred to a private veterinary clinic in Tehran because of theirs abnormal signs, such as polydipsia, vomiting, diarrhea, abdominal distention, restlessness, hyperactivity, polyuria, ataxia, tremors, and seizures. In ECG, tachycardia and premature ventricular contractions were seen. Diagnosis is based on history of exposure, along with clinical signs that occurred in 8-12 hours of ingestion.Methocarbamol (100 mg/kg, slow IV) and diazepam (0.5 mg/kg, slow IV) administered for tremors and/or mild seizures. Arrhythmias treated with propranolol(0.05 mg/kg).Fluid diuresis used for stabilizing cardiovascular function and hasten urinary excretion of methylxanthines. Partially Improvement was seen by 3days and all of the clinical signs were completely suppressed one week later.