Content Of Tea Research Articles

VARIATION OF HEMIN PROTEIN CONCENTRATION IN GREEN TEA AFTER SWEETENING

Green tea is obtained by processing the leaves of the Camellia sinensis plant. Tea contains active substances that act on the central nervous system, the circulatory system and is a good diuretic. It is rich in mineral salts and vitamins, especially vitamin C, and helps to strengthen the immune system. Tea leaves contain tannins, amino acids, carbohydrates and essential oils that give the tea its colour and flavour. Green tea is recognized for its high antioxidant potential, being very rich in polyphenolic compounds, vitamins, and pro-vitamins.Chlorophyll is remarkably similar in structure to hemoglobin, the oxygen-carrying pigment found in the red blood cells of mammals and other vertebratesHemoproteins are the photosynthetic and respiratory cytochromes, involved in electron transfer, and the globin that bind oxygen.In order to determine the variation of heme protein concentration in green tea after sweetening, UV-VIS optical spectrometry and mathematical statistics were used.

Impact of Tea and Coffee Polyphenol Concentration on the Syneresis and Physicochemical Properties of Set Yogurt during Refrigerated Storage

Impact of Tea and Coffee Polyphenol Concentration on the Syneresis and Physicochemical Properties of Set Yogurt during Refrigerated Storage

Assessment of Heavy Metals in Tea Plantation Soil and Their Uptake by Tieguanyin Tea Leaves and Potential Health Risk Assessment in Anxi County in Southeast China

Evaluating heavy metal pollution in tea plantation soil and conducting potential health risk assessments are crucial for ensuring the safety of tea consumers. However, soil heavy metal pollution levels and dietary exposure risk remain poorly understood, and there is no consensus on how soil physicochemical properties affect heavy metal concentrations. In this study, seventy-three soil samples and corresponding tea leaves from main tea-producing regions in Anxi County were analyzed for arsenic (As), chromium (Cr), lead (Pb) and copper (Cu) concentrations. The results showed that mean concentrations of As, Cr, Cu and Pb in the soil did not exceed respective risk screening values in China (GB 15618-2018). The concentrations of As, Cr, Cu and Pb in the tea leaves were within limiting values of the Chinese National Food Safety Standard, and the bioaccumulation factor of heavy metals in descending order was Cu > Pb > As > Cr. The hazard index values of heavy metals indicated no potential human health risk. Soil pH, EAl, EA and AP were the main controlling factors for heavy metal in soil and tea leaves. Cu and Pb concentrations in tea leaves were positively correlated with soil Cu and Pb concentrations. These results provide a scientific basis for effective monitoring and management in tea plantations and for controlling potential risks in tea leaves.

Influence of Soursop Fruit Tea Concentration on the Fermentation and Quality Attributes of Water Kefir Beverages

Soursop is a seasonal and highly perishable fruit with a short shelf life after harvest. Therefore, fermentation with water kefir could be a great combination to develop a novel probiotic and dairy-free alternative beverage with distinctive flavors all year round. Therefore, this study aimed to formulate and characterize fermented beverages utilizing soursop fruit tea and water kefir microorganisms. An evaluation of physical parameters, antioxidant capacity, microbiological profiles, and sensory attributes was conducted after the fermentation process of the soursop water kefir. The result indicated that pH and Brix values remained in the acceptance range for consumption. According to microbiological results, all water kefir samples provided a high number of lactic acid bacteria and yeasts, although no significant differences were observed in microbial counts. Furthermore, the organoleptic acceptability of the fruit water kefirs was encouraging, particularly at a 1% initial soursop fruit tea concentration, with favorable ratings for taste and overall acceptability.

Effects of protein on green tea quality in a milk-tea model during heat treatment: Antioxidant activity, foaming properties, and unbound small-molecule metabolome

Tea drinks/beverage has a long history and milk is often added to enhance its taste and nutritional value, whereas the interaction between the tea bioactive compounds with proteins has not been systematically investigated. In this study, a milk-tea model was prepared by mixing green tea solution with milk and then heated at 100°C for 15 min. The milk tea was then measured using biochemical assay, antioxidant detection kit, microscopy as well as HPLC-QTOF-MS/MS after ultrafiltration. The study found that as the concentration of milk protein increased in the milk-tea system, the total phenol-protein binding rate raised from 19.63% to 51.08%, which led to a decrease in free polyphenol content. This decrease of polyphenol was also revealed in the antioxidant capacity, including 2,2-diphenyl-1-picrylhydrazyl radical scavenging ability and ferric ion reducing antioxidant power, in a dose-dependent manner. Untargeted metabolomics results revealed that the majority of small-molecule compounds/polyphenols in tea, such as epigallocatechin gallate, (-)-epicatechin gallate, and Catechin 5,7,-di-O-gallate, bound to milk proteins and were removed by ultrafiltration after addition of milk and heat treatment. The SDS-PAGE and Native-PAGE results further indicated that small molecule compounds in tea formed covalent and non-covalent complexes by binding to milk proteins. All above results partially explained that milk proteins form conjugates with tea small-molecule compounds. Consistently, the particle size of the tea-milk system increased as the tea concentration increased, but the polymer dispersity index decreased, indicating a more uniform molecular weight distribution of the particles in the system. Addition of milk protein enhanced foam ability in the milk-tea system but reduced foam stability. In summary, our findings suggest that the proportion of milk added to tea infusion needs to be considered to maintain the quality of milk-tea from multiple perspectives, including stability, nutritional quality and antioxidant activity.

Mathematical optimization of multilinear and artificial neural network regressions for mineral composition of different tea types infusions

The objective of this study was to investigate the change in mineral composition depending on tea variety, tea concentration, and steeping time. Four different tea varieties, black Ceylon (BC), black Turkish (BT), green Ceylon (GC), and green Turkish (GT), were used to produce teas at concentrations of 1, 2, and 3%, respectively. These teas were produced using 7 different steeping times: 2, 5, 10, 20, 30, 45, and 60 min. It was also aimed to optimize the regression equations utilizing these factors to identify parameters conducive to maximizing Zn, K, Cu, Mg, Ca, Na, and Fe levels; minimizing Al content, and maintaining Mn level at 5.3 mg/L. The optimal conditions for achieving a Mn content of 5.3 mg/L in black Turkish tea entailed steeping at a concentration of 1.94% for 11.4 min. Variations in K and Mg levels across teas were inconsistent with those observed for other minerals, whereas variations in Al, Cu, Fe, Mn, Na, and Zn levels exhibited a close relationship. Overall, mineral levels in tea can be predicted through regression analysis, and by mathematically optimizing the resultant equations, the requisite conditions for tea production can be determined to achieve maximum, minimum, or target mineral values.

Medicinal cannabis tea contains variable doses of cannabinoids and no terpenes.

Tea is a recommended way of administration of prescribed cannabis plant products in Denmark. We aimed to investigate the cannabinoid and terpene doses contained in different teas. We analysed tetrahydrocannabinol (THC), tetrahydrocannabinolic acid (THCA), cannabidiol (CBD), cannabidiolic acid (CBDA), and terpene concentrations in three repeated preparations of each type of tea, and in plant material. In standard tea, concentrations of THC were [median (min-max)] 9.5 (2.3-15), 19 (13-34), and 36 (26-57) μg/mL for products with a labelled content of 6.3%, 14%, and 22% total THC (THC + THCA), respectively. The CBD concentration in tea from a product labelled with 8% total CBD (CBD + CBDA) was 7.5 (1.9-10) μg/mL. Based on this, the recommended starting amount of 0.2L of the different teas would contain between 0.46 and 11.3mg THC, and 0.38 to 2.0mg CBD. Adding creamer before, but not after boiling, increased the THC and CBD concentration 2.3-4.4 and 2.1-fold, respectively. Terpenes were detected in plant material, but not in tea. The study elucidates THC and CBD doses in different teas, which may assist the clinician's choice of cannabis product. Moreover, it underscores the need for caution as administration as tea can result in exposure to different doses, even when the same cannabis product is used.

The effect of element type and sintering temperature of MFe2O4 sensing electrode on gadolinium doped cerium oxide-based mixed potential triethylamine sensor

The effect of element type and sintering temperature of MFe2O4 sensing electrode on gadolinium doped cerium oxide-based mixed potential triethylamine sensor

Polyphenol content, antioxidant and anti-inflammatory activities of Georgian wine and green Tea

This comprehensive study explores the health-promoting properties of Georgian green tea and red wine, focusing on their antioxidant and anti-inflammatory activities, as well as polyphenol content. Utilizing the DPPH and FRAP methods, we observed impressive results, with green tea showcasing a remarkable FRAP activity of 61.2 % of ascorbic acid activity set as 100 %, surpassing red wine at 18.2 %. Comparative assessments against ascorbic acid for antioxidant activity and Sodium diclofenac for anti-inflammatory effects further underscored green tea's prowess. Intriguingly, green tea exhibited a substantial anti-inflammatory activity of 20 % of Sodium diclofenac also set as 100 %, outshining red wine at 3.7 %. Polyphenol content, a key contributor to health benefits, revealed green tea's concentration at 7.5 % (w/w), red wine's - 4.4 % g/l. These findings highlight the potential of green tea and red wine as a potent source of bioactive compounds with implications for cellular health, inflammation mitigation, and chronic disease prevention. The results prompt a closer look at dietary choices, advocating for the incorporation of green tea to harness its multifaceted health benefits. As we delve into the molecular richness of these beverages, our findings provide valuable insights into the potential therapeutic avenues offered by these popular and culturally significant drinks.

Estimation of annual effective radiation dose and cancer risk due to tea consumption

The current study aims to assess the radioactive health risks and their levels due to tea consumption. Fresh tea leaves were plucked from different locations in the Gumero tea farmland in Ilubabour zone, Ethiopia. High-resolution gamma-ray spectroscopy was used to measure the activity concentrations of artificial and natural radionuclides (e.g., 40K, 232Th, and 238U) in the samples. Radiological indicators such as committed dose rate (DR) and excess lifetime cancer risk, LCR (i.e., the cancer death risk due to lifetime exposure to carcinogens, ignoring the contribution of natural background risk) were evaluated to ascertain the radioactive risk to humans in the tea samples. DR and LCR, two radiological markers, were assessed to determine the radioactive risk to humans in the tea samples. The finding shows that the radiological hazards assessment of 238U and 232Th revealed that the Gumero tea leaves have natural radioactivity levels within the internationally recommended limit, while that of 40K was higher than the limit. Comparing the current study with other studies, it was found that the yearly effective doses and nuclide radioactivity concentrations in tea leaves were similar.

Determination of Element Concentration of Brewed Tea Consumed in Iran Using ICP-OES: A Risk Assessment Study.

Tea is a popular drink enjoyed by many people around the world. However, it is important to note that impurities and contaminants in tea can potentially threaten human health when consumed. The main objective of this research is to assess the concentration of 16 trace elements (As, Fe, Al, Co, B, Li, Cd, Ba, Pb, Cr, Zn, Hg, Ni, Mn, Sb, and Sn) present in different types brewed of tea by using the ICP-OES (the inductively coupled plasma optical emission spectrometer) device, and the human health risks related to its use were evaluated. In this study, manganese (Mn) indicated the highest mean concentration in black (917.64µg/kg) and green tea (912.89µg/kg), respectively. Our study showed that the highest mean concentration of element boron (B) was (44.36µg/kg) in Stachys lavandulifolia brewed tea. Among different packaging, tea bag samples had the highest concentration of Mn (1025.65µg/kg) and aluminum (Al) (396.63µg/kg). However, those unpacked posed the lowest content of Mn (188.13µg/kg) and Al (100.47µg/kg). The lead (Pb), mercury (Hg), and cadmium (Cd) concentrations in all samples were lower than the maximum limit of the Iranian standard and the WHO. In general, the amount of tea metal in Iranian samples was higher than in imported samples. Also, increasing the brewing time (10 min) can be effective in the solubility and extraction of metals such as B, Hg, cobalt (Co), iron (Fe), and lithium (Li). Further, the correlation between the amount of metals and type in tea samples was evaluated with principal component analysis. Based on the conducted non-carcinogenic risk assessment by the Monte Carlo simulation, the hazard index (HI), due to ingestion of heavy metals via tea in the 5-min brewing of tea, was 7.39E - 03 and 2.09E - 03, and in the 10-min brewing of tea, it was 3.20E - 02 and 9.07E - 03 for children and adults, respectively. Therefore, there was no significant non-carcinogenic risk from tea consumption.

Evaluation of heavy metal concentration in black tea and coffee marketed in Erbil, Iraq: a consumer health risk assessment

ABSTRACT Black tea and coffee are popular and widely consumed beverages worldwide. However, the potential accumulation of heavy metals in food products raises concerns regarding their toxicity. In this study, we investigated the concentrations of arsenic (As), cadmium (Cd), copper (Cu), chromium (Cr), lead (Pb), manganese (Mn), zinc (Zn), and iron (Fe) in 102 samples of black tea and coffee purchased from Erbil city market in Iraq. Additionally, we determined the Hazard Quotient (HQ) and Hazard Index (HI) levels of heavy metal intake to evaluate the non-carcinogenic health risks for adult consumers. The mean concentrations of As, Cd, Cu, Cr, Pb, Mn, Zn, and Fe in black tea and coffee were found to be 0.023, 0.11, 10.29, 0.60, 1.69, 294.99, 25.59, and 39.80 mg/kg, respectively. In the case of black tea, the highest mean concentration observed was 607.28 mg/kg for Mn, while the lowest was 0.035 mg/kg for Cd in coffee. Arsenic was below the detection limit in coffee. Our results revealed that, except for Cd content in some tea samples, the concentrations of the studied metals were within the standard levels. The HQ and HI values for all elements were found to be less than one, indicating no adverse health effects associated with consuming these beverages. However, continuous monitoring is essential to ensure the ongoing safety of black tea and coffee.

Determination of aluminium concentrations in black, green, and white tea samples: effects of different infusion times and teapot species on aluminium release

Tea is the most consumed beverage in the world after water and contains heavy metals and trace elements that may cause potential negative effects on health. Aluminium (Al) concentrations in black, green, and white tea with different infusion times and teapot materials were evaluated in this study. Commercially available tea samples were brewed in 5 different teapots, consisting of aluminium, copper, glass, steel, and porcelain materials for 5, 10, and 15 min. Al concentrations in tea samples were determined by high-performance liquid chromatography with a fluorescence detector. Al concentrations in tea samples were in the range of 38.46 ± 5.08–844.75 ± 10.86 µg/L. Both teapot type (p < 0.001) and infusion time (p < 0.001) significantly influenced Al concentrations in tea samples. The interaction between tea type, teapot material, and infusion time was statistically significant (p < 0.001). The hazard ratio was less than 1 for black and white tea infusions except for one sample whereas it was greater than 1 for green tea. These data suggest that green tea consumption might be a potential risk factor for Al exposure.

Zn-doped CeO2 nanorod based dispersive solid phase micro-extraction of lead in water, black pepper, lentils and tea samples

Zn-doped CeO2 nanorod based dispersive solid phase micro-extraction of lead in water, black pepper, lentils and tea samples

Development of Small-scale Integrated Hydroponics—Animal Waste Bioreactor (AWB) for Romaine Lettuce (Lactuca sativa L. var. longofolia) Production

As improper processing and disposal of animal waste cause negative impacts on the environment, the animal industry sector must shift to more sustainable practices to lessen these effects. Recently, the application of the circular economy concept in agriculture, using animal waste as part of nutrient cycling, has emerged as a sustainable approach. The study aims to develop and test the small-scale integrated hydroponics-animal waste bioreactor (AWB) for romaine lettuce production using chicken manure tea (CMT) derived from dried chicken manure as a primary nutrient source. Three integrated hydroponics-AWB systems, with varying concentrations of CMT at 1,000 ppm, 1,200 ppm, and 1,400 ppm total dissolved solids (maintained within an upper and lower bound of 50 ppm), were constructed, tested, and compared to conventional hydroponics that used a nutrient solution maintained at 1,000 ppm TDS. The test result suggests that the ideal concentration of CMT in the system is 1,000 ppm. Within the optimum manure tea concentration, the small-scale integrated hydroponics-AWB produced romaine lettuce with growth parameters comparable to conventional hydroponics. In addition, increasing the CMT concentration to 1,400 ppm negatively impacts the plant growth parameters of romaine lettuce. The developed small-scale integrated hydroponics-AWB system provides a viable approach for growing lettuce using animal waste as the major source of nutrients. The developed production system could help mitigate the negative environmental effects of improper handling and disposal of animal waste and dependence on chemical-based nutrient solutions in hydroponic crop production.

Effects of cannabis tea on the development of zebrafish embryo and larval behaviour

Cannabis is a known illicit substance that is often used by pregnant women, however its potential impact on the developing embryo is unknown. Thus, this experiment used a zebrafish model to investigate how chronic exposure to cannabis tea affected zebrafish development and behaviour. Zebrafish embryos were exposed to cannabis tea prepared at concentrations of 5, 10 and 15 mg/L for 96 hours. The resulting mortality, hatching duration, morphological abnormalities, startle response, light-dark preference and optokinetic response were then assessed. The cannabis tea had a significant impact on the mortality, hatching duration, startle response and optokinetic response. The tea had a LC50 of 11.20 mg/L with mortality increasing with the tea concentration. The hatching duration increased with cannabis exposure (p = 0.046). For the startle response, the effect of the cannabis tea was concentration dependent, with higher concentrations reducing the startle response (p &lt; 0.001). The optokinetic response initially increased at the lowest cannabis dose, but subsequent increase caused reductions in the response (p &lt; 0.001). As for the morphological abnormalities, deformities were only observed in larvae exposed to cannabis. The cannabis tea also showed both anxiolytic and anxiogenic effects on the larvae in the light-dark preference assay. These results were comparable to studies investigating THC and CBD separately. Although more comprehensive research is required to offer a better understanding, these findings aid in our knowledge of how a cannabis whole extract influences development.

Targeting Cancer Hallmarks with Epigallocatechin Gallate (EGCG): Mechanistic Basis and Therapeutic Targets.

Epigallocatechin gallate (EGCG) is a catechin, which is a type of flavonoid found in high concentrations in green tea. EGCG has been studied extensively for its potential health benefits, particularly in cancer. EGCG has been found to exhibit anti-proliferative, anti-angiogenic, and pro-apoptotic effects in numerous cancer cell lines and animal models. EGCG has demonstrated the ability to interrupt various signaling pathways associated with cellular proliferation and division in different cancer types. EGCG anticancer activity is mediated by interfering with various cancer hallmarks. This article summarize and highlight the effects of EGCG on cancer hallmarks and focused on the impacts of EGCG on these cancer-related hallmarks. The studies discussed in this review enrich the understanding of EGCG's potential as a therapeutic tool against cancer, offering a substantial foundation for scientists and medical experts to advance scientific and clinical investigations regarding EGCG's possibility as a potential anticancer treatment.

Effect of Various Types of Sugars on Antioxidant Activity and Physico-chemical Properties of Kombucha Fermented Whey

Kombucha or known as SCOBY (Symbiotic Culture of Bacteria and Yeast) is a fermented tea beverage with the addition of sugar then fermented for 7-14 days. Recent studies showed kombucha conceivably used for milk fermentation, such as fermented whey, yogurt, and fermented milks. Sugar is added to kombucha as carbon source for microorganisms in kombucha. Type of sugar, sugar concentration, tea concentration, temperature and incubation time are factors that affect kombucha fermentation. The aims of this study were to determine the effect of various types of sugars on antioxidant activity (2,2-diphenyl-1-picrylhydrazyl (DPPH)) and physicochemical properties (pH, titratable acidity, total dissolved solid, and CIE L* a* b* color space value). The various types of sugars were granulated white sugar (G1), coconut sugar (G2), palm sugar (G3) and no sugar addition as control (G0). Fermented whey using 10% kombucha liquor, 3% kombucha cellulose and 10% sugar addition, whey then fermented at 37oC for 14 hours. Result demonstrated that using of various types of sugars significantly affected antioxidant activity, CIE L*a*b* color space value, pH, titratable acidity, total dissolved solid and vitamin C content. The highest vitamin C content was G3 (0.91±0.05 mg/100ml), kombucha fermented whey using palm sugar. Any type of sugar could be used on kombucha fermented whey, and the highest antioxidant activity (DPPH) was fermented whey kombucha with the addition of coconut sugar (G2) (86.79±10.94%).

Enhancing classification rate of electronic nose system and piecewise feature extraction method to classify black tea with superior quality

Enhancing classification rate of electronic nose system and piecewise feature extraction method to classify black tea with superior quality

Role of triethanolamine complexing agent in chemical bath deposition of tin sulfide thin films: Microstructural and optical properties

Role of triethanolamine complexing agent in chemical bath deposition of tin sulfide thin films: Microstructural and optical properties