What are some examples of methylxanthines?
Caffeine (present in coffee) and theobromine (present in chocolate) are also methylxanthines. Theophylline is the most well known and most commonly used methylxanthine.
What are methylxanthines and why are they in coffee?
Methylxanthines are a group of naturally occurring substances found in coffee, tea, chocolate and related foodstuffs. Naturally occurring theophylline (1,3-dimethylxanthine), and its ester derivative aminophylline, are the only compounds in clinical use. They are chemically similar to caffeine.
What foods and beverages contain xanthine?
Xanthine is found in coffee, tea and cola drinks as well as substances like caffeine, theobromine and theophylline. Caffeine is found in chocolate and cocoa, while theobromine is present in cocoa, tea and foods containing these things. Theophylline is present in all of the above foods and beverages.
What is methylxanthine used to treat?
The methylxanthines, theophylline, and dyphylline are used in the treatment of airways obstruction caused by conditions such as asthma, chronic bronchitis, or emphysema. Caffeine (present in coffee) and theobromine (present in chocolate) are also methylxanthines. Theophylline is the most well known and most commonly used methylxanthine.
What foods contain theophylline?
Theophylline is found in black tea and to a lesser extent in green coffee, cocoa cotyledon and dried mate.
Does coffee contain methylxanthines?
Linked to three of the most consumed beverages (coffee, tea, and cacao) are the most popular methylxanthines: caffeine, theophylline, and theobromine (Table 1). Caffeine is the most abundant methylxanthine in coffee, its level being smaller in chocolate than in coffee.
Does tea have methylxanthine?
Tea leaves contain methylxanthines, such as caffeine, which have various physiological and pharmacological effects in vivo. Caffeine, theobromine and theophylline were analysed in various teas to determine the exposure amount and health risk of methylxanthine intake from tea.
Which chocolate contains the most methylxanthine?
Generally, unsweetened baker's chocolate and dark chocolates are the most dangerous as they will contain a very high level of methylxanthines. Milk chocolate has a much lower concentration, and white chocolate has a nearly negligible amount of these compounds.
Does green tea contain methylxanthines?
Caffeine (1,3,7-trimethylxanthine), theobromine (3,7-dimethylxanthine), and theophylline (1,3-dimethylxanthine) are the most well-known compounds of the family of methylxanthines and are naturally present in tea leaves, yerba mate, coffee beans, cocoa beans, kola nuts and guarana berries.
What are the 3 methylxanthines?
3 MethylxanthineTheobromine.Theophylline.Bronchodilating Agent.Caffeine.Hydrogen.Carbon 14.Methyltransferase.7 Methylxanthine.More items...
Why does tea keep me awake more than coffee?
Tea leaves have more caffeine than coffee beans before they are brewed. Prepared, however, tea is diluted quite a bit more than most coffees. Each will vary depending on how strong you like it, though.
What foods should be avoided when taking theophylline?
This medicine may add to the central nervous system (CNS) stimulant effects of caffeine-containing foods or beverages such as chocolate, cocoa, tea, coffee, and cola drinks. Avoid eating or drinking large amounts of these foods or beverages while using this medicine.
What are the side effects of methylxanthines?
Common side effects of methylxanthines include:Stomach upset and heartburn. The heartburn may make breathing more difficult, especially for people with asthma.Trouble sleeping (insomnia).Headache.Nervousness or irritability.Rapid heart rate (tachycardia).Rapid breathing (tachypnea).
Does all chocolate have methylxanthines?
Chocolate bars labeled as a percentage of cocoa/cacao are based on unsweetened chocolate, ie, a 65% cacao bar would contain ~293 mg (450 mg × 0.65) of methylxanthines per ounce (10.4 mg/g). White chocolate is a negligible source of methylxanthines.
What if my dog ate chocolate but seems fine?
Chocolate is poisonous to dogs mostly because of its theobromine content, which dogs are unable to metabolize effectively. If your dog eats chocolate, you should monitor them closely and seek veterinary attention if they show any symptoms, or if they are very young, pregnant or have other health concerns.
Why do dogs get sick when they eat chocolate?
Yes, chocolate is toxic to dogs. While rarely fatal, chocolate ingestion can result in significant illness. Chocolate is toxic because it contains a chemical called theobromine, as well as caffeine. Theobromine is the main toxin in chocolate and is very similar to caffeine.
How much methylxanthines are in cocoa powder?
In general, however, the total methylxanthine concentration of dry cocoa powder is ~800 mg/oz (28.5 mg/g), unsweetened (baker's) chocolate is ~450 mg/oz (16 mg/g), semisweet chocolate and sweet dark chocolate is ~150–160 mg/oz (5.4–5.7 mg/g), and milk chocolate is ~64 mg/oz (2.3 mg/g).
Does cocoa butter contain methylxanthines?
The main toxic components of chocolate are methylxanthine compounds, specifically theobromine and caffeine. Cocoa beans and their hulls have relatively high methylxanthine levels. Cocoa butter (the fat from the cocoa bean) contains very little methylxanthine.
What are the side effects of methylxanthines?
Common side effects of methylxanthines include:Stomach upset and heartburn. The heartburn may make breathing more difficult, especially for people with asthma.Trouble sleeping (insomnia).Headache.Nervousness or irritability.Rapid heart rate (tachycardia).Rapid breathing (tachypnea).
Does tea contain caffeine or theophylline?
Tea contains 4 substances that have stimulating effects on your brain. The best known is caffeine, a potent stimulant that you can also get from coffee, soft drinks, and energy drinks. Tea also contains two substances related to caffeine: theobromine and theophylline.
Where are methylxanthines found?
Methylxanthines are adsorbed in the gastrointestinal tract and can penetrate into the central nervous system, exerting psychostimulant actions, which are more evident in acute intake [ 9 ]. These compounds, and caffeine in particular, are adenosine receptor antagonists in the brain and enhance arousal, mood, and concentration levels [ 10, 11, 12 ]. The toxicity of methylxanthines in humans is relatively low and moderate consumption presents some health benefits [ 9, 13, 14, 15, 16 ]. High levels are required to produce undesirable adverse side effects, such as diuresis, cardiovascular and metabolic effects, bronchial relaxation and increased secretion of gastric acids [ 15, 17 ].
What are the effects of methylxanthine?
Methylxanthines present psychostimulant effects. These compounds have low toxicity and their consumption at moderate levels presents some beneficial health effects, whereas some significant risk appears at high levels. Samples of common types of methylxanthine-containing beverages and foods consumed in Spain were analyzed to determine their content. Caffeine was the methylxanthine that was most found in the samples investigated. Instant coffees gave the highest caffeine percentage (18–44 mg·g −1 ). Green and scented teas were found to have a caffeine dry-weight content (8–26 mg·g −1) equivalent to ground coffees (13–23 mg·g −1 ), but black and pu-erh teas (18–30 mg·g −1) had a higher caffeine content. The evaluation of the most conventional methods for preparing espresso coffees showed that an espresso contains between 88–116 mg of caffeine. In the case of tea beverages, the amount of caffeine present was 2–3 times smaller than in espresso coffees. Energy drinks showed a similar caffeine content (80–106 mg) as espresso coffees. Chocolates had the lowest caffeine content. It has been found that none of the foods evaluated reach the recommended daily intake limit of 400 mg of caffeine with a single dose. This limit can be reached with 4–5 doses in the case of coffees and energy drinks. In the case of chocolates, the methylxanthine compound detected at large levels was theobromine, with amounts ranging from 4 to 10 mg·g −1 for dark chocolates.
What is the most commonly consumed stimulant in the central nervous system?
Caffeine (1,3,7-trimethylxanthine), theobromine (3,7-dimethylxanthine), and theophylline (1,3-dimethylxanthine) are the most well-known compounds of the family of methylxanthines and are naturally present in tea leaves, yerba mate, coffee beans, cocoa beans, kola nuts and guarana berries. Moreover, caffeine is probably the most broadly consumed central nervous system stimulant in the world [ 1, 2, 3 ].
What is the caffeine content of chocolate?
Thirty-one samples of chocolate drinks from 11 commercial brands were also evaluated. A mean caffeine level of 18.4 mg/L (standard deviation (sd) = 5.4) (median = 16.9 (14.9–21.5)) and a mean theobromine level of 205.7 mg/L (sd = 76.6) (median = 192.9 (156.3–266.1)) were found. The reported levels of cocoa content for the different commercial brands evaluated varied from 0.9% to 1.5%. Therefore, five new samples of the commercial brand with the lowest reported cocoa amount (0.9%) and seven new samples of brand with the highest amount of cocoa (1.5%) were analyzed and compared. A significant difference was obtained for the levels of caffeine content ( p = 0.024), which were 13.3 mg/L (sd = 1.5) for the brand with 0.9% cocoa and 23.2 mg/L (sd = 7.2) for the brand with 1.5% cocoa, and for the theobromine content ( p = 0.007), which were 148.4 mg/L (sd = 13.7) and 267.2 mg/L (sd = 79.6), respectively.
Which beverage has the least caffeine?
Chocolate drinks showed the lowest caffeine concentration (mean = 18.4 mg/L) of all the beverages evaluated. As in the case of bottled teas, the source of caffeine for these samples is of natural origin (cocoa beans), which also leads to a large variability between samples (RSD = 29.3%). Despite the fact that the methylxanthine present at the highest concentration in cocoa is theobromine (around 10 times more than caffeine in the samples evaluated), this compound produces very minor subjective effects in comparison with caffeine [ 44 ]. Therefore, taking into account only caffeine concentrations, chocolate drinks are the beverages that would be expected to present the least psychostimulant activity.
What is the solvent used in a gradient elution?
The solvents used were (A) Milli·Q water containing 0.1% acetic acid (pH ≈ 3.2) and (B) methanol. The mobile phase composition started at 10% B for 4 min, increased linearly to 25% B in 1 min and held for 10 min, followed by a linear increase of B to 90% in 7 min. The final conditions were held for 8 min. For the cleaning and regeneration of the column between runs, a linear decrease of B to 10% in 5 min was applied and these conditions were held for 3 min. A total run time of 30 min plus 8 min of regeneration was required for each analysis.
Is caffeine a dietary supplement?
Energy drink manufacturers classify their beverages as liquid dietary supplements because they contain herbs and other natural ingredients and, therefore, have different regulatory issues and there is no limit on the caffeine that can be added to dietary supplements. In the European Union, a beverage is considered to have a high caffeine content when it contains >150 mg/L of caffeine, with the exception of those based on coffee, tea or coffee or tea extract, and its label must indicate “high caffeine content” and express this content in mg per 100 mL [ 31 ]. This regulation requires energy drink manufacturers to label their caffeine content.
What are Methylxanthines?
Methylxanthines are a unique class of drug that are derived from the purine base xanthine. Xanthine is produced naturally by both plants and animals. The methylxanthines, theophylline, and dyphylline are used in the treatment of airways obstruction caused by conditions such as asthma, chronic bronchitis, or emphysema. Caffeine (present in coffee) and theobromine (present in chocolate) are also methylxanthines.
How do methylxanthines work?
Experts are not sure exactly how methylxanthines work but research has shown they inhibit the enzyme phosphodiesterase, antagonize adenosine receptors, and at lower dosages, their effects on histone deacetylase activity are believed to contribute to their immunomodulatory effects.
What is the role of theophylline?
The main role of theophylline and dyphylline is to help maintain good airway control in chronic, persistent, airways disease.
Is coffee a methylxanthine?
Caffeine (present in coffee) and theobromine (present in chocolate) are also methylxanthines. Theophylline is the most well known and most commonly used methylxanthi ne. At low dosages, it has an immunomodulatory, anti-inflammatory and bronchoprotective effect. Higher dosages are needed for its bronchodilator effect; however, ...
Where are methylxanthines found?
However, the methylxanthines have also been found to be antagonists of adenosine at purinergic P 1 receptors and receptors for adenosine have been found in the heart, where adenosine decreases the force of contraction, and in the bronchi, where it causes bronchoconstriction.
What are the effects of methylxanthines on AMP?
All three methylxanthines inhibit the enzyme phosphodiesterase, which is responsible for the breakdown of cyclic AMP. Thus, in those systems where cyclic AMP is a second messenger (see Chapters 3 and 10 ), the effects of the transmitters will be potentiated and prolonged, and it has been demonstrated that inhibitors of phosphodiesterase potentiate responses in the autonomic nervous system which are mediated by β1 and β2 -adrenoceptors. Such an action by the methylxanthines can readily explain the cardiac stimulation and bronchodilation which they produce. This hypothesis is now regarded with suspicion as it has been found that the concentrations of methylxanthines needed to produce appreciable inhibition of phosphodiesterases are much greater than would be expected to occur in vivo. However, the methylxanthines have also been found to be antagonists of adenosine at purinergic P 1 receptors and receptors for adenosine have been found in the heart, where adenosine decreases the force of contraction, and in the bronchi, where it causes bronchoconstriction. Thus an antagonist action by the methylxanthines at adenosine receptors is a more likely mechanism of action. The methylxanthines have other actions, including effects on the translocation of calcium ions intracellularly and the potentiation of inhibitors of the synthesis of prostaglandins; it is possible that either or both of these mechanisms may contribute to their effects.
What is theophylline in tea?
Theophylline is a methylated xanthine alkaloid (1,3-dimethylxanthine) that is found naturally in tea. Its half-life is approximately 30 hours in the neonate, compared to 7 hours in adults. 223 Theophylline has more potent inotropic, vasodilator, bronchodilator, and diuretic actions compared to caffeine because of its more efficacious PDE inhibition and adenosine antagonism. Theophylline may cause less respiratory center stimulation than caffeine but enhances diaphragmatic contractility to a greater extent by facilitating increased neuromuscular transmission with increased tidal volumes.158 It is also an inhibitor of lymphocyte function as well as mast cell histamine release; by these mechanisms it can reduce airway inflammation.224 In the adult, theophylline is eliminated by hepatic biotransformation and urinary excretion. In the newborn, however, the hepatic biotransformation with N -demethylation is absent; instead, the occurrence of N -7-methylation produces caffeine. 225 The therapeutic plasma concentration is about 7 to 20 mg/L. In one study, levels greater than 6.6 mg/L controlled apneic spells, whereas cardiovascular toxicity with tachycardia was noted only at levels greater than 13.0 mg/L. 226 Some newborns manifested toxicity at levels of 9.0 mg/L of transplacentally acquired theophylline. Because of the problems at these lower levels and because of the potential additive effects of the caffeine produced from theophylline, 10 mg/L may be a desirable level. Signs of toxicity may include irritability, diaphoresis, diarrhea, seizures, gastroesophageal reflux, and tachycardia.227 The usual intravenous loading dose of theophylline is 4.0 to 6.0 mg/kg, with a maintenance dose of 1 mg/kg every 8 hours or 2 mg/kg every 12 hours. Its low cost makes its use especially advantageous in low-resource settings.
What are the three most important alkaloids derived from xanthine?
Methylxanthines. The three most important alkaloids derived from xanthine are caffeine (Figure 16.2a), theophylline (Figure 16.2b) and theobromine (Figure 16.2c ). They all occur naturally, being found in various plants from which beverages are made. They are therefore present in drinks such as tea, coffee and cocoa, and also cola-flavoured drinks.
Which enzyme is involved in the metabolism of caffeine?
Cytochrome P450 1A2 (CYP1A2) , the principal enzyme involved in caffeine metabolism in the liver, is absent in the placenta and the fetus, therefore the exposure of the fetoplacental unit to caffeine depends on maternal caffeine metabolism, which is influenced by genetic and environmental factors.
Does xanthine help with apnea?
Xanthine therapy appears to increase minute ventilation, improve CO2sensitivity, decrease hypoxic depression of breathing, enhance diaphragmatic activity, and decrease periodic breathing. The likely major mechanism of action is through competitive antagonism of adenosine receptors. Adenosine acts as an inhibitory neuroregulator in the central nervous system via activation of adenosine A1receptors (Herlenius et al, 1997). In addition, activation of adenosine A2Areceptors appears to excite GABAergic interneurons, and released GABA may contribute to the respiratory inhibition induced by adenosine (Mayer et al, 2006).
Does xanthine relax smooth muscle?
These substances have a number of pharmacological actions: they stimulate the CNS; they act on the kidney to cause diuresis; they stimulate cardiac muscle, and they relax smooth muscle, particularly bronchial muscle. All three xanthine derivatives have these actions but vary in potency.
How to get rid of xanthine in kidneys?
Taking care to eat a low-purine diet can help keep xanthine out of the body. Fatty and xanthine-rich foods should be avoided, while eating plenty of carbohydrates may help the body process uric acid. Drinking lots of water is also important. Between 8 and 12 cups of clear fluids daily may reduce the chance of kidney stone formation.
What is the chemical that causes kidney stones?
This chemical is a purine, which is found in many foods. Xanthines are found in certain foods that some people have difficulty processing. The condition known as Xanthinuria can lead to too much xanthine being present in the body. As a result, sufferers are at dramatically increased risk of developing kidney stones, gout and muscle disease.
Can you eat coffee with xanthine?
Medications may be used to help treat symptoms, but doctors recommend avoiding foods that contain xanthines in the first place, as stated by MedicineNet. Xanthine is found in coffee, tea and cola drinks as well as substances like caffeine, theobromine and theophylline.
What is the source of caffeine?
The kola nut is the seed of the kola tree and a natural source of caffeine ( 1, 2, 3, 12 ).
Where is caffeine found in plants?
Caffeine is a substance that’s naturally present in the leaves, seeds, and fruits of many plants, where it acts as an herbicide and insect repellant ( 1, 2 ).
What is the most commonly consumed psychostimulant substance?
Caffeine is the most commonly consumed psychostimulant substance in the world. The term “psychostimulant” means that it increases the activity of the nervous system ( 1, 3 ).
What is coffee made of?
Coffee is a brewed beverage prepared from coffee beans, which are a natural source of caffeine ( 1, 2, 3 ).
Does decaf coffee contain caffeine?
In case you’re wondering, decaffeinated coffee still contains caffeine. However, it has reduced levels compared with regular coffee.
Is yerba mate a good source of caffeine?
Also known as Paraguay tea, yerba mate is a natural source of caffeine. Experts have praised it as a heart-friendly drink with numerous potential health benefits, which include its antimicrobial and antioxidant properties ( 22, 23 ).