Enhanced photocatalytic performance of polymeric C_3N_4 doped with theobromine composed of an imidazole ring and a pyrimidine ring

Molecular doping has been proven to be an effective approach to adjusting the electronic structure of polymeric carbon nitride(PCN)and thus improving its optical properties and photocatalytic activity.Herein,theobromine,a compound composed of an imidazole ring and a pyrimidine ring,was first copolymerized with urea to prepared doped PCN.Experimental investigations and theoretical calculations indicate that,a narrowing in band gap and a positive shift in valence band positon happened to the theobromine doped PCN,owing to the synergistic effect between the pyrimidine ring and the imidazole ring in the theobromine molecule.Moreover,it is shown that the doping with theobromine at a suitable mass fraction makes the obtained sample exhibit decreased photoluminescent emission,enhanced photocurrent density,and reduced charge-transport resistance.Consequently,an enhancement in the photocatalytic activity for water oxidation is found for the sample,which oxygen evolution rate is 4.43 times higher than that of the undoped PCN.This work sheds light on the choice of the molecular dopants for PCN to improve its photocatalytic performance.

Studies of cocoa tea, a wild tea tree containing theobromine

Camellia ptilophylla Chang is a wild tea tree containing theobromine and is caffeine-free.Lots of researches have been conducted for its domestication since it was discovered to contain theobromine in its shoots.First,its pharmacological and physiological effects have been studied,demonstrating that it can be used as a new resource of tea as daily and healthy beverage.Cocoa tea differs from traditional tea in that it does not excite the nervous system.Second,various ways of propagation have been investigated,and sexless cutting has been the method adopted currently.Third,through selection and breeding,plantation of cocoa tea can be set up to cultivate new varieties,and cocoa tea of different flavors such as green cocoa tea,oolong cocoa tea,and black cocoa tea can be processed.Thus,cocoa tea will become a choice in the tea market.

Controllable Transdermal Drug Delivery of Theobroma cacao Extract Based Polymeric Hydrogel against Dermal Microbial and Oxidative Damage

Human dermal layers are directly bared to the external environmental adversities like pollution, radiation, dust along with various chemical and mechanical stress conditions which constantly lead to the oxidative stress, eventually forming free radicals. These conditions also support the dermal microbial infections by invading the cutaneous layers. Therefore, the most efficient approach accepted globally to combat these complications is to opt for transdermal application of exogenous antioxidants which helps in reducing the ill effects of oxidative stress and promotes the DNA repair. However, many scientific findings exhibited the potential role of Theobroma cacao for providing efficient skin protection. Theobroma cacao known for its vital procyanidin flavonoids, phenolic compounds, methylxanthines, catechin and epicatechin phytoconstituents with numerous health benefits, besides helping in smoothening and softening the damaged skin. These therapeutic benefits of cocoa phytocompounds are attributed to its anti-inflammatory and antioxidative characteristics. This study addresses the fabrication and optimizations of Theobroma cacao extract loaded carbopol hydrogel system for increased antioxidative and antimicrobial effects. It was found in the studies that the hydrogel-based T. cacao extract (TCHG) has significantly improved the therapeutic index of the extract, making it more suitable for transdermal application. The optimized hydrogel was further characterized by physicochemical parameters, SEM analysis and in-vitro release kinetics. The reported findings showed the sustained compound release with comparatively significant antimicrobial activity of TCHG against microbial (Pseudomonas fluorescens, Bacillus licheniformis, Micrococcus luteus, Aspergillus niger, Trichoderma harzianum, Rhizopus oryzae) infections. Also, the higher ROS quenching ability of TCHG as compared to T. cacao extract promises to be an effective transdermal formulation.

Bio-Medical Aspects of Purine Alkaloids

This review shortly summarized bio-medical activities of purine alkaloids, caffeine (caf), theophyline (top) and theobromine (tob). Caffeine potentiates the cytotoxicity of a variety of DNA domaging agents. Caffeine increased antitumor activity of some cancerostatic drugs. Caffeine inhibits the carcinogenic activity of cigarette smoke, significantly potentiating the therapeutic effect of acetaminophenol, cyclophosphoramide, enhances lipid oxidation, affects the central nervous system and alters cardiovascular system. Theophyline has expressive anti-inflammatory and antiasthmatic effect, and enhanced mobilization of lipid reduces the brain regional adenylate cyclase activity, facilitates glucose inhibition. Theophyline is muscle relaxant, vasodilator, diuretic and cardiac stimulant. Theobromine increases antitumor activity of adriamycin and doxorubicin, has expressive anti-inflammatory effect and it is classical diureticum. Several examples of caffeine with some organic substrates as well as with copper are also outlined. Increasing activity of the respective drugs in the present of the purine alkaloids can be ascribed to direct interaction as was proved by X-ray data of some caffeine adducts with organic substances as well as Cu(II) complexes.

Use of the ¹³C/¹²C, ¹⁵N/¹⁴N and ¹⁸O/¹⁶O Isotopic Ratios of Theobromine and Caffeine in the Characterization of Geographic Origin

The aim of this work is to characterize the geographical origin of cocoa beans and coffee beans. This study aims to contribute to the traceability of raw materials in order to fight against falsification. For this purpose, we based our work on the measurement of isotope ratios in 13C, 15N and 18O. The multi-element isotope ratios have been evaluated as a means to distinguish fermented cocoa beans of different geographic and varietal origins. The isotopic ratios of 13C, 15N and 18O were measured in theobromine obtained from samples of fermented cocoa beans. Twenty-two (22) samples of different geographical origins covering the four mainland cocoa producing areas were analyzed on the one hand and on the other hand, 16 caffeine samples from various origins were also analyzed. The treatment of the values resulting from these isotopic analyzes by statistical methods, namely the principal component analysis (PCA) makes it possible to visualize the discriminations between the different origins. The most discriminating variables identified as responsible for the geographic and varietal differences were the δ15N, δ13C and δ18O values of cocoa beans and certain extracts and tissues. We have shown that the isotope ratios are correlated with the altitude and precipitation conditions encountered in the different cocoa growing regions.