Tea Caffeine Research Articles

Black tea caffeine in the radiochemical separation of 89Zr produced from alpha particle irradiation on natY

Black tea caffeine in the radiochemical separation of 89Zr produced from alpha particle irradiation on natY

Metabolomic profiling of in vitro and in situ grown Nilgiris tea reveals unique signatures for breeding decaffeinated varieties

This study was begun by establishing an in vitro culture in UPASI 9, a Nilgiris tea clone (Camellia sinensis) by optimising various factors. Anatomical studies demonstrated that use of lower carbendazim concentration for sterilisation (0.2%) produced viable and healthy explants for callus initiation. To confirm the genetic consistency of the regenerated plants, gene-specific SSR markers were developed and utilised. GC-MS was employed to analyse volatile metabolites extracted from callus, stem, micro shoots, and leaves of the UPASI 9 tea genotype. The results revealed distinct compositions of metabolites in each sample. More interestingly, caffeine was exclusively detected in leaf samples but absent in all other investigated tissues, despite the presence of Tea Caffeine Synthase (TCS) gene-specific SSRs. Thus, this study provided unique information on the absence of caffeine in in vitro grown Nilgiris tea clone, UPASI 9, as decaffeinated tea has a unique niche in the global market.

Analysis of Caffeine, Tannin and Total Phenol Content of Tea Leaves from Sirah Kencong Blitar Plantation

Analysis of Caffeine, Tannin and Total Phenol Content of Tea Leaves from Sirah Kencong Blitar Plantation

Caffeine and Purine Derivatives: A Comprehensive Review on the Chemistry, Biosynthetic Pathways, Synthesis-Related Reactions, Biomedical Prospectives and Clinical Applications.

Caffeine and purine derivatives represent interesting chemical moieties, which show various biological activities. Caffeine is an alkaloid that belongs to the family of methylxanthine alkaloids and it is present in food, beverages, and drugs. Coffee, tea, and some other beverages are a major source of caffeine in the human diet. Caffeine can be extracted from tea or coffee using hot water with dichloromethane or chloroform and the leftover is known as decaffeinated coffee or tea. Caffeine and its derivatives were synthesized via different procedures on small and large scales. It competitively antagonizes the adenosine receptors (ARs), which are G protein-coupled receptors largely distributed in the human body, including the heart, vessels, brain, and kidneys. Recently, many reports showed the effect of caffeine derivatives in the treatment of many diseases such as Alzheimer's, asthma, parkinsonism, and cancer. Also, it is used as an antioxidant, anti-inflammatory, analgesic, and hypocholesterolemic agent. The present review article discusses the synthesis, reactivity, and biological and pharmacological properties of caffeine and its derivatives. The biosynthesis and biotransformation of caffeine in coffee and tea leaves and the human body were summarized in the review.

Simultaneous determination of six catechins and caffeine in tea and wine using salting-out assisted liquid-liquid extraction and high-performance liquid chromatography with ultraviolet detection.

Catechins, renowned for their antioxidant properties and health benefits, are commonly present in beverages, particularly tea and wine. An efficient and cost-effective salting-out assisted liquid-liquid extraction (SALLE) method has been developed and validated for the simultaneous determination of six catechins and caffeine in tea and wine samples using high-performance liquid chromatography-ultraviolet (HPLC-UV). This method demonstrates outstanding performance: linearity (1-120µg/mL, r2>0.999), accuracy (96.5%-103.4% recovery), and precision (≤14.7% relative standard deviation), meeting validation requirements set by the US Food and Drug Administration. The reduced sample size (0.1g) minimizes matrix interferences and costs without compromising sensitivity. All analytes were detected in Camellia sinensis teas, with green tea displaying the highest total catechin content (47.5-100.1mg/mL), followed by white and black teas. Analysis of wine samples reveals the presence of catechin in all red and white wines, and epigallocatechin gallate in all red wine samples, highlighting the impact of winemaking processes on catechin content. The SALLE-HPLC-UV approach represents a green alternative by eliminating organic waste, surpassing conventional dilution methods in specificity and sensitivity for catechin determination. AGREEprep assessment emphasizes the strengths of the SALLE procedure, including material reusability, throughput efficiency, minimal sample requirements, low energy consumption, and the absence of organic waste generation.

Caffeine: Benefits and Risks for Health and Wellbeing

Background: Tea contains a variety of compounds, including caffeine, which have a range of health impacts. The presence of caffeine in tea often raises questions about the benefits of its consumption, including potential effects on cognition, behavior, mood and exercise performance as well as areas of concern such as anxiety, stress, hydration and heart health. The aim of this review is to evaluate the benefits and risks of caffeine consumption with a focus on tea and other compounds present in tea, which may interact with caffeine. Methods: Evidence was considered from Randomised Controlled Trials (RCTs) published over the last 15 years investigating the effects of caffeine on cognition, alertness, behavior, hydration and mood. Systematic reviews, meta-analyses and expert panel reviews were included in the wider discussion. Results: Evidence suggests that caffeine intakes of 3-6mg/kg/bw/(body weight)/day may benefit cognitive function and exercise performance in adults. Many expert bodies state that there are no safety concerns with daily intakes of ≤ 200mg caffeine in pregnant women and ≤ 400mg in other adults. Evidence indicates that children and adolescents should limit their daily caffeine intake to 2.5mg/kg/bw. Tea contains a lower concentration of caffeine than most other caffeinated drinks as well as providing fluid for hydration and polyphenolic compounds for health, particularly cardiovascular health. L-theanine in tea moderates the potential negative impact of caffeine on stress and anxiety whilst improving attention and speed of mental performance. Conclusion: On balance, moderate amounts of caffeine provide benefits in terms of cognitive function, alertness and exercise performance in adults with minimal risk of adverse effects. Further research is required to determine safe, beneficial intakes in children and adolescents. Tea, with its lower caffeine content, in combination with flavonoid polyphenols, fluoride and L-theanine, may provide an acceptable benefit/risk ratio for people aged 4 years and over, assuming age-appropriate intakes of 1-8 daily servings.

Utilizing a cell-free protein synthesis platform for the biosynthesis of a natural product, caffeine.

Natural products are a valuable source of pharmaceuticals, providing a majority of the small-molecule drugs in use today. However, their production through organic synthesis or in heterologous hosts can be difficult and time-consuming. Therefore, to allow for easier screening and production of natural products, we demonstrated the use of a cell-free protein synthesis system to partially assemble natural products in vitro using S-Adenosyl Methionine (SAM)-dependent methyltransferase enzyme reactions. The tea caffeine synthase, TCS1, was utilized to synthesize caffeine within a cell-free protein synthesis system. Cell-free systems also provide the benefit of allowing the use of substrates that would normally be toxic in a cellular environment to synthesize novel products. However, TCS1 is unable to utilize a compound like S-adenosyl ethionine as a cofactor to create ethylated caffeine analogs. The automation and reduced metabolic engineering requirements of cell-free protein synthesis systems, in combination with other synthesis methods, may enable the more efficient generation of new compounds. Graphical Abstract.

Effect of Fermentation Time on Antioxidants Activity and Sensory Evaluation of the Kombucha Tea Beverage Prepared with Hibiscus and Tamarind

A fermented beverage called kombucha is made by fermenting green or black tea with sugar and adding the SCOBY symbiotic bacteria under aerobic conditions. Hibiscus and tamarind drinks are traditional drinks that are distinguished in their functional and sensory characteristics. Therefore, in this research, work has been done to transform hibiscus and tamarind drinks from traditional and functional drinks into fermented drinks with new functional and therapeutic properties as well as sensory distinctiveness in taste and color. Also, the study estimated the pH, total phenolic and flavonoid content, as well as DPPH and sensory evaluation in the novel drinks and compared them with traditional kombucha tea. In addition, the study determined the proper fermentation time with incubated yeast (SCOBY). The measurements of day seven and fourteen fermentation were taken for Kombucha tea, Kombucha tea with hibiscus, and Kombucha tea with tamarind then compared with black tea. Caffeine in black tea was more than in Kombucha tea and others may be due to the black tea contained the highest total phenolic and flavonoids which were 164.53 and 12.91 μg/mL, respectively. Moreover, the radical scavenging ability of the hibiscus and tamarind seems to point out at act as functional foods. Fermented hibiscus beverage has the best sensory evaluation among all resulting beverages. The juice showed a difference in color according to the drink and the fermentation period, in addition to the different colors of the SCOBY With different beverages. So, it could be recommended that the fortification of the Kombucha tea beverage with hibiscus and tamarind enhances its nutritional qualities and phytochemical compositions.

Electrochemical Sensing Platform Based on Carbon Dots for the Simultaneous Determination of Theophylline and Caffeine in Tea.

A simple and selective method for the determination of caffeine (CAF) and theophylline (THEO) has been developed for a glassy carbon electrode (GCE) modified with a composite including carbon dots (CDs) and chitosan (CS). To our knowledge, there are no previous studies that analyze a CDs-modified GCE for the presence of CAF and THEO. The electrochemical behavior of a GCE modified with a CDs-CS composite was studied in acidic medium by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Considering the sensor analytical parameters, the same linear concentrations range was found for CAF and THEO ranging from 1 × 10-5 to 5 × 10-3 mol L-1 with the same detection limit (LOD) of 1 × 10-6 mol L-1. The reproducibility and repeatability data were satisfactory in terms of RSD%. Moreover, the storage stability was evaluated, evidencing good results whatever the experimental conditions used. The developed sensor was applied for the simultaneous determination of CAF and THEO in tea and drug, and results were compared with those obtained with HPLC-ESI-MS in SIR mode as an independent method optimized on purpose. The electrochemical sensor presents the undoubled advantages in terms of cheapness, portability, and ease of use, since it does not require skilled personnel.

Determination of Caffeine and Few Metals in Halabja Tea and Comparing with Various Tea Samples in Erbil Markets

This paper deals with two main parts: part (I) performed the caffeine levels evaluation in three commercial tea leaves (black, green, and herbal tea) in Erbil markets and Halabja city. The caffeine was extracted by liquid-liquid extraction using dichloromethane and chloroform solvents. The extracted caffeine was purified, and then identified by melting point (M.P), ultraviolet (UV) and Fourier transform infrared (FT-IR) spectroscopy that provides spectra identical to the standard caffeine crystals. The level of caffeine in black tea was found greater than in green tea, presumably because black tea are made of older tea leaves, in contrast, there is no caffeine obtained from Halabja tea. Part (II) mentioned the determination of metal ions (lithium, sodium, potassium, and calcium) in 5 brands of black and green tea (leaves and bags) in addition to Halabja tea; using flame atomic emission (FAES) and flame atomic absorption (FAAS) spectroscopy. The tea beverages were prepared by three different methods: (chemically, infusion, and continuous infusion). There was a moderate quantity of sodium, potassium, and calcium was determined in the 5 brands of tea, while lithium found in the trace. Halabja tea was free from caffeine while lithium, sodium, potassium, and calcium elements of the Halabja herbal tea are all higher than all the other types of tea leaves and bags

Engineering of zeolitic imidazolate frameworks based on magnetic three-dimensional graphene as effective and reusable adsorbent to enhance the adsorption and removal of caffeine from tea samples

As more and more adverse health effects of caffeine are being discovered, decaffeinated drinks are receiving increasing attention. In this work, a magnetic imidazole zeolite backbone compounded with three-dimensional graphene was successfully synthesized as a solid adsorbent using a layer-by-layer self-assembly technique, which can rapidly and effectively adsorb caffeine from tea. Meanwhile, the structure and properties of caffeine in tea were investigated by various physicochemical characterization tools. The analytical data showed that Fe3O4@3DGA@ZIF-8 had a specific surface area of 162.9754 m2/g and an adsorption capacity of up to 19.57 mg/g with a maximum adsorption rate of 96.55%, which could be maintained with good adsorption repeated utilization three times. The adsorption isotherm and the adsorption kinetic better fit with the Langmuir model and the preudo-second order kinetic model, respectively. Therefore, Fe3O4@3DGA@ZIF-8 is a good magnetic adsorbent for the separation and the effective removal of caffeine from tea sample.

The transcription factor CsS40 negatively regulates TCS1 expression and caffeine biosynthesis in connection to leaf senescence in Camellia sinensis.

Caffeine is considered as one of the most important bioactive components in the popular plant beverages tea, cacao, and coffee, but as a wide-spread plant secondary metabolite its biosynthetic regulation at transcription level remains largely unclear. Here, we report a novel transcription factor Camellia sinensis Senescnece 40 (CsS40) as a caffeine biosynthesis regulator, which was discovered during screening a yeast expression library constructed from tea leaf cDNAs for activation of tea caffeine synthase (TCS1) promoter. Besides multiple hits of the non-self-activation CsS40 clones that bound to and activated TCS1 promoter in yeast-one-hybrid assays, a split-luciferase complementation assay demonstrated that CsS40 acts as a transcription factor to activate the CsTCS1 gene and EMSA assay also demonstrated that CsS40 bound to the TCS1 gene promoter. Consistently, immunofluorescence data indicated that CsS40-GFP fusion was localized in the nuclei of tobacco epidermal cells. The expression pattern of CsS40 in 'Fuding Dabai' developing leaves was opposite to that of TCS1; and knockdown and overexpression of CsS40 in tea leaf calli significantly increased and decreased TCS1 expression levels, respectively. The expression levels of CsS40 were also negatively correlated to caffeine accumulation in developing leaves and transgenic calli of 'Fuding Dabai'. Furthermore, overexpression of CsS40 reduced the accumulation of xanthine and hypoxanthine in tobacco plants, meanwhile, increased their susceptibility to aging. CsS40 expression in tea leaves was also induced by senescence-promoting hormones and environmental factors. Taken together, we showed that a novel senescence-related factor CsS40 negatively regulates TCS1 and represses caffeine accumulation in tea cultivar 'Fuding Dabai'. The study provides new insights into caffeine biosynthesis regulation by a plant-specific senescence regulator in tea plants in connection to leaf senescence and hormone signaling.

Artikel Review : Bioaktivitas Bunga Rosella (Hibiscus sabdariffa L.) Beserta Pemanfaatannya

Hibiscus sabdariffa is a species of the Malvaceae family which has long been used by humans as a traditional medicine. The use of Hibiscus sabdariffa as a traditional medicine is related to its bioactivity. Hibiscus sabdariffa has several pharmacological potentials, namely: 1) anticancer; 2) antioxidants; 3) antibacterial; 4) antiaging; 5) antiseptic; and 6) antihypertensive. The method of writing this article is a literature review published online, especially on Google Scholar using the keywords Hibiscus sabdariffa, bioactivity and utilization of Hibiscus sabdariffa. The results of this review state that rosella flowers (Hibiscus sabdariffa L.) have potential as anticancer, antioxidants, antihypertensive antibacterials, and low caffeinated tea drinks.

Miniaturized solid-phase microextraction of caffeine in tea samples: assessing the environmental friendliness of the methods with the GAPI tool

Over the last few decades, there has been a significant increase in tea consumption worldwide, leading to a growing concern for the quality and nutritional value of tea. The demand for high-quality tea has necessitated the development of new analytical approaches to ensure adherence to quality standards and process control. One area of particular importance is the control of caffeine in tea, as regular consumption of caffeine in large quantities can contribute to the leaching of beneficial minerals from the human body. To address this issue, in this work have developed a rapid technique for determining caffeine in tea samples using miniaturized solid-phase microextraction (mini-SPME) combined with chromatography-mass spectrometry (GC-MS). The study included the screening of teas available in the market of Kazakhstan. In this study optimized the basic parameters of miniaturized solid-phase microextraction of caffeine from tea samples, including fiber coating, extraction temperature, extraction time, and pre-incubation time. The fiber coating used in the study was DVB/CAR/PDMS, and the optimal extraction temperature was found to be 90°C, with an extraction time of 20 minutes and a pre-incubation time of 5 minutes. The developed method is efficient and can be used for determination and control of traces of caffeine in tea samples. Furthermore, the study evaluated the environmental friendliness of the methods for analyzing caffeine in teas using the GAPI tool. The GAPI tool is a software program that assesses the environmental impact of a chemical process by considering several parameters, such as toxicity, energy consumption, and waste generation. The results of the study showed that the developed method was environmentally friendly

Genome-Wide Investigation and Functional Analysis Reveal That CsKCS3 and CsKCS18 Are Required for Tea Cuticle Wax Formation.

Cuticular wax is a complex mixture of very long-chain fatty acids (VLCFAs) and their derivatives that constitute a natural barrier against biotic and abiotic stresses on the aerial surface of terrestrial plants. In tea plants, leaf cuticular wax also contributes to the unique flavor and quality of tea products. However, the mechanism of wax formation in tea cuticles is still unclear. The cuticular wax content of 108 germplasms (Niaowang species) was investigated in this study. The transcriptome analysis of germplasms with high, medium, and low cuticular wax content revealed that the expression levels of CsKCS3 and CsKCS18 were strongly associated with the high content of cuticular wax in leaves. Hence, silencing CsKCS3 and CsKCS18 using virus-induced gene silencing (VIGS) inhibited the synthesis of cuticular wax and caffeine in tea leaves, indicating that expression of these genes is necessary for the synthesis of cuticular wax in tea leaves. The findings contribute to a better understanding of the molecular mechanism of cuticular wax formation in tea leaves. The study also revealed new candidate target genes for further improving tea quality and flavor and cultivating high-stress-resistant tea germplasms.

Circular Economy Electrochemistry: Creating Additive Manufacturing Feedstocks for Caffeine Detection from Post-Industrial Coffee Pod Waste.

The recycling of post-industrial waste poly(lactic acid) (PI-PLA) from coffee machine pods into electroanalytical sensors for the detection of caffeine in real tea and coffee samples is reported herein. The PI-PLA is transformed into both nonconductive and conductive filaments to produce full electroanalytical cells, including additively manufactured electrodes (AMEs). The electroanalytical cell was designed utilizing separate prints for the cell body and electrodes to increase the recyclability of the system. The cell body made from nonconductive filament was able to be recycled three times before the feedstock-induced print failure. Three bespoke formulations of conductive filament were produced, with the PI-PLA (61.62 wt %), carbon black (CB, 29.60 wt %), and poly(ethylene succinate) (PES, 8.78 wt %) chosen as the most suitable for use due to its equivalent electrochemical performance, lower material cost, and improved thermal stability compared to the filaments with higher PES loading and ability to be printable. It was shown that this system could detect caffeine with a sensitivity of 0.055 ± 0.001 μA μM-1, a limit of detection of 0.23 μM, a limit of quantification of 0.76 μM, and a relative standard deviation of 3.14% after activation. Interestingly, the nonactivated 8.78% PES electrodes produced significantly better results in this regard than the activated commercial filament toward the detection of caffeine. The activated 8.78% PES electrode was shown to be able to detect the caffeine content in real and spiked Earl Grey tea and Arabica coffee samples with excellent recoveries (96.7-102%). This work reports a paradigm shift in the way AM, electrochemical research, and sustainability can synergize and feed into part of a circular economy, akin to a circular economy electrochemistry.

Incidental nanoparticles in black tea alleviate DSS-induced ulcerative colitis in BALB/c mice.

As the dominant herbal drink consumed worldwide, black tea exhibits various health promoting benefits including amelioration of inflammatory bowel diseases. Despite extensive studies on the tea's components, little is known about the bioactivities of nanoparticles (NPs) which were incidentally assembled in the tea infusion and represent the major components. This study investigated the alleviative effects of black tea infusion, the isolated black tea NPs, and a mixture of caffeine, epigallocatechin-3-gallate, gallic acid and epicatechin gallate on dextran sodium sulfate (DSS)-induced ulcerative colitis. The results showed that both the black tea infusion and the NPs significantly alleviated colitis, suppressed the mRNA levels of pro-inflammatory cytokines TNF-α, IL-6, and IL-1β, and suppressed the DSS-induced loss of cell-cell junction proteins (e.g., E-cadherin, ZO-1, and claudin-1) and increase of p-STAT3. The mixture of four tea components, which is the analogue of bioactive payloads carried by the NPs, was much less effective than the tea infusion and NPs. It shows that the NPs elevate the efficiency of polyphenols and caffeine in black tea in restoring the intercellular connection in the intestine, inhibiting mucosal inflammation, and alleviating ulcerative colitis. This work may inspire the development of tea-based therapeutics for treating inflammatory bowel diseases and have wide influences on value-added processing, quality evaluation, functionalization, and innovation of tea and other plant-based beverages.

Deeply functional identification of TCS1 alleles provides efficient technical paths for low-caffeine breeding of tea plants.

Caffeine is an important functional component in tea, which has the effect of excitement and nerve stimulation, but excessive intake can cause insomnia and dysphoria. Therefore, the production of tea with low-caffeine content can meet the consumption needs of certain people. Here, in addition to the previous alleles of the tea caffeine synthase (TCS1) gene, a new allele (TCS1h) from tea germplasms was identified. Results of in vitro activity analysis showed that TCS1h had both theobromine synthase (TS) and caffeine synthase (CS) activities. Site-directed mutagenesis experiments of TCS1a, TCS1c, and TCS1h demonstrated that apart from the 225th amino acid residue, the 269th amino acid also determined the CS activity. GUS histochemical analysis and dual-luciferase assay indicated the low promoter activity of TCS1e and TCS1f. In parallel, insertion and deletion mutations in large fragments of alleles and experiments of site-directed mutagenesis identified a key cis-acting element (G-box). Furthermore, it was found that the contents of purine alkaloids were related to the expression of corresponding functional genes and alleles, and the absence or presence and level of gene expression determined the content of purine alkaloids in tea plants to a certain extent. In summary, we concluded TCS1 alleles into three types with different functions and proposed a strategy to effectively enhance low-caffeine tea germplasms in breeding practices. This research provided an applicable technical avenue for accelerating the cultivation of specific low-caffeine tea plants.

Estimation of Caffeine in Different Marketed Samples of Tea

The objective of this study was estimate of Caffeine in Different Marketed Samples of Tea Although there were no significant differences between the orders of caffeine content among the tested tea brands, the method with chloroform isolation exhibited significantly lower results and the highest results obtained by the micromethod using H2SO4 at 273 nm UV wavelength with regard to other methods applied for the determination of caffeine. The non-laborious chemical method of determination of caffeine in tea samples using Lead oxide and Chloroform has shown us the caffeine levels in various samples. It is also true that caffeine in tea can have positive and negative effects on the organism consuming it.

Metabolomic and Transcriptomic Analyses Reveal the Characteristics of Tea Flavonoids and Caffeine Accumulation and Regulation between Chinese Varieties (Camellia sinensis var. sinensis) and Assam Varieties (C. sinensis var. assamica).

Flavonoids and caffeine are the major secondary metabolites with beneficial bioactivity for human health in tea plants, and their biosynthesis pathway and regulatory networks have been well-deciphered. However, the accumulation traits of flavonoids and caffeine in different tea cultivars was insufficient in investigation. In this study, metabolomic and transcriptomic analyses were performed to investigate the differences of flavonoids and caffeine accumulation and regulation between Chinese varieties, including the 'BTSC' group with green leaf, the 'BTZY' group with purple foliage, and the 'MYC' group comprising Assam varieties with green leaf. The results showed that most of the flavonoids were down-regulated in the 'MYC' group; however, the total anthocyanin contents were higher than that of the 'BTSC' group while lower than that of the 'BTZY' group. An ANS (Anthocyanin synthase) was significantly up-regulated and supposed to play a key role for anthocyanin accumulation in the 'BTZY' group. In addition, the results showed that esterified catechins were accumulated in the 'BTSC' and 'BTZY' groups with high abundance. In addition, SCPL1A (Type 1A serine carboxypeptidase-like acyltransferases gene) and UGGT (UDP glucose: galloyl-1-O-β-d-glucosyltransferase gene) potentially contributed to the up-accumulation of catechins esterified by gallic acid. Interestingly, the results found that much lower levels of caffeine accumulation were observed in the 'MYC' group. RT-qPCR analysis suggested that the expression deficiency of TCS1 (Tea caffeine synthase 1) was the key factor resulting in the insufficient accumulation of caffeine in the 'MYC' group. Multiple MYB/MYB-like elements were discovered in the promoter region of TCS1 and most of the MYB genes were found preferentially expressed in 'MYC' groups, indicating some of which potentially served as negative factor(s) for biosynthesis of caffeine in tea plants. The present study uncovers the characteristics of metabolite accumulation and the key regulatory network, which provide a research reference to the selection and breeding of tea varieties.