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: It was found that large doses of theophylline and theobromine clearly reduced the duration of cortical afterdischarge, and Repeated administration of caffeine appeared to cause no further or even less prolongation of after discharge than that produced by the first dose suggesting that tachyphylaxis occurred.
4 citations
TL;DR: Xanthines (caffeine, theophylline and theobromine) and purine have very low quantum yields of fluorescence in ethanol and acetonitrile solutions at room temperature ( Φ f ) as mentioned in this paper.
4 citations
TL;DR: In this article , HPLC analysis assessed 126 unique Camellia germplasms belonging to three camellia species, C. sinensis var. pubilimba Chang (Csp), C. gymnogyna Chang and C. crassicolumna Chang (ccC), and concluded that theobromine was the predominant purine alkaloid in all species.
Abstract: Tea (Camellia sinensis var. sinensis) is a widely consumed caffeine-containing beverage, however the Camellia genus also includes other species, which are consumed as tea in their local growing regions. Presently, HPLC analysis assessed 126 unique Camellia germplasms belonging to three Camellia species, C. sinensis var. pubilimba Chang (Csp), C. gymnogyna Chang (CgC) and C. crassicolumna Chang (CcC). Theobromine was the predominant purine alkaloid in all species, representing over 90% of purine alkaloids in Csp and CgC, and 50% in CcC. Significant variability existed in purine alkaloid patterns both between and within species, and some germplasms possessed highly unique alkaloid profiles. Sensory evaluation and quality composition analysis of green tea products produced from the three Camellia species suggested their unsuitability for use in tea production due to their unpalatable flavor. The results of this study revealed the differences in purine alkaloids and main quality components between Camellia species and tea, which contributed to understand why tea, rather than other Camellia species, has become a popular beverage in the world after long-term artificial selection. In addition, unique alkaloid profiles suggest usefulness of these germplasm resources in future breeding of decaffeinated tea plant varieties and alkaloid metabolism research.
4 citations
TL;DR: In this article , the effects of in vitro digestion on the antioxidant activity and release of phenolics, xanthine alkaloids, and L-theanine contents of matcha were investigated.
Abstract: This study investigates the effects of in vitro digestion on the antioxidant activity and release of phenolics, xanthine alkaloids, and L-theanine contents of matcha. It establishes digestibility values between 61.2–65.8%. Considering native matcha, the rutin content (303–479 µg/g) reached higher values than catechin (10.2–23.1 µg/g). Chlorogenic acid (2090–2460 µg/g) was determined as predominant. Rutin, quercetin, ferulic, ellagic, and caffeic acid were the least-released phenolics, and their remaining residues reached 76–84%. Protocatechuic, hydroxybenzoic acid, epigallocatechin, and epigallocatechin-3-gallate were the best-released phenolics, with the remaining residues under 1%. Caffeine, L-theanine, and theobromine contents in native matcha reached 16.1, 9.85, and 0.27 mg/g, respectively. Only caffeine (3.66–5.26 mg/g) and L-theanine (0.09–0.15 mg/g) were monitored in the undigested residue, representing 13 and 0.1% of the remaining part, respectively. A chemiluminescence assay showed that water-soluble antioxidants showed significant antioxidant activity in native matcha, while lipid-soluble compounds showed higher antioxidant activity in the undigested samples. Cinnamic and neochlorogenic acids were determined as the main contributors to the ACW values in the undigested matcha, epicatechin, and quercetin in the ACL fraction. The application of the digestion process reduced the antioxidant activity by more than 94%. SEM has proved specific digestion patterns of in vitro digestibility of matcha.
4 citations
TL;DR: In this article, the apparent molar volumes (V2,ϕ) and viscosity B-coefficients for xanthine drugs (caffeine, theophylline, and theobromine) in aqueous (0.09999-0.99989) mol·kg−1 MgCl2 solutions have been determined from measured densities ρ and visosities η, respectively at T = (288.15 to 318.15) K and at pressure p = 101.3 kPa.
Abstract: Apparent molar volumes (V2,ϕ) and viscosity B-coefficients for xanthine drugs (caffeine, theophylline, and theobromine) in aqueous (0.09999–0.99989) mol·kg–1 MgCl2 solutions have been determined from measured densities ρ and viscosities η, respectively at T = (288.15 to 318.15) K and at pressure p = 101.3 kPa. These studies indicate the decrease in solubilization of xanthine drugs with increasing ionic strengths of MgCl2 solutions. The results have also been interpreted in terms of structure making/breaking ability of solutes. Spectroscopic studies also support that hydrophilic–ionic interactions are greater at lower concentrations of MgCl2, which descend and finally become weaker at higher concentrations of MgCl2. This type of behavior may also be understood in terms of a large dehydration effect.
4 citations