Caffeine biological activities

Foods derived from cocoa beans have been consumed by humans since at least 460 to 480 AD. The source of cocoa beans, the species Theobroma, contains a variety of biologically active components. These include the purine alkaloids theobromine, caffeine, and theophylline. Structurally, they are methylated xanthines and, thus, are often referred to as methylxanthines. Theobromine (3, 7-dimethylxanthine) is the predominant purine alkaloid in cocoa and chocolate. Caffeine (1, 3, 7-trimethylxanthine), the major purine alkaloid found in coffee and tea, is found in cocoa and chocolate at about one eighth the concentration of theobromine. Only trace amounts of theophylline (1, 3-dimethylxanthine) are detected in cocoa and chocolate products. 

Three of the most important methylxanthenes are theophylline, theobromine, and caffeine. Methylxanthenes exhibit a similar range of biological activity. 

The creatures of the world, both animals and plants, produce a wide range of biologically active substances. Biologically active substances produced by animals or plants that cause an adverse effect are called toxins. Toxins refers only to toxic agents produced by animals and plants, not toxic substances such a lead or pesticides. The classification of a substance as a toxin tends to be in the eye of the beholder. Is caffeine, a naturally occurring agent in many plants, a toxin or just a pharmacologically active compound or both ... 

In general, plants do very well in their environments, notwithstanding the omnipresence of a multitude of potential insect herbivores and a number of vertebrate herbivores as well. Some plant species are very insecticidal, as a consequence of their producing a variety of alkaloids including nicotine, piperine, lupine alkaloids, steroidal alkaloids, ephedrine, berberine, strychnine, gramine, and caffeine.37 These biologically active alkaloids also function as deterrents. In terms of families, caffeine is the the most widely distributed alkaloid, a fact that may be... 

Despite this diversity, the alkaloids are still considered as reference standards for bitter taste in sensory evaluation methodologies caffeine and quinine solutions are used to train panelists to recognize the bitter taste and to give comparative evaluations of other bitter principles. This is obviously also due to the fact that these two alkaloids are among the most important for their use in food, not only as contaminants but as active principles selected for their taste profile and biological activity. 

To test the predictive power of this relationship, six biologically active molecules were used as a validation set. Vanillin was included in this set to investigate the predictive capability for molecules with internal hydrogen bonds. The predicted log Pqw for this data set are listed in Table 3 together with experimentally determined values. Several of the predicted values are very close to the experimental, e.g. caffeine and vanillin The largest deviation is found for clonidine, for which our relationship overestimate the log Pqw value by only 0.51 units. These results clearly indicate that eq. 20 has a predictive capability also for more complex molecules. 

Despite the fact that a plethora of dietary factors could, and will, affect the absorption characteristics of phytochemicals, this area has not been systematically explored. One reason might be the complexity of dietary factors and their interactions that could affect absorption. A nonexhaustive list would include the volume and composition of the food consumed, pH, caloric density, viscosity, nutrients (carbohydrates, protein, fat, fibers), alcohol, caffeine, and the presence of other phytochemicals. Such dietary factors affect the functional status, motility, and acidity of the gastrointestinal tract in a complex manner and modify the physicochemical properties, formulation, and dissolution characteristics of the compound of interest. Calcium in dairy products, for example, has the potential to chelate tetracyclines and fluoroquinolones and, thereby, reduce their bioavailability and biological activity [31]. 

There are many components in chocolate. The biologically active stimulants are caffeine and theobromine. The amine compounds are tyramine and phenylethylamine or PEA. 

Documented effects The biological activity is due to the presence of saponins, and removal of the saponins from the tincture leads to complete loss of the pharmacological properties (Ivanova 1963). The sedative effect of this species is nearly twice as strong as that of Valeriana (Tolmachev 1976). The roots of this species reduce excitability of the nervous system. Clinical tests showed that application of an alcohol infusion stopped or noticeably reduced chest pain as well as nervous and cardiovascular excitation caused by hypodermic introduction of caffeine (Akopov 1990). 

The purine bases, caffeine, theophylline, and theobromine, yield the corresponding 6-monothio- and 2,6-dithio derivatives upon reaction with LR without a solvent under microwave irradiation. Thionation of the carbonyl groups in the nucleobases of nucleotides leads to interesting special types of thiolactams, which are expected to exhibit modified biological activities. P3u imidine nucleosides are selectively thionated in the 4-position of the nu-cleobase. The mild reaction conditions applied allow the conversion of nucleosides with labile glycosidic bonds, such as 5,6-dihydropyrimidine-(113) and 2, 3 -dideoxynucleosides. Thiononucleosides with unnatural bases (114) or sugar moieties (115), (116) can also be prepared. 

Apart from the biological activities of caffeine, those of chlorogenic acid (which is present in substantial quantities in coffee) should not he ignored, as chlorogenic acid is reported to have stimulant, diuretic, and choleretic properties (see artichoke and honeysuckle)-, it also has allergenic properties (morton 3). 

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