Tea Extract Research Articles

Brewing method-dependent changes of volatile aroma constituents of green tea (Camellia sinensis L.).

The determination of optimal levels of green tea amount and brewing time would have a crucial role in the accumulation of desired aromatic volatile compounds to meet worldwide market demand. Aroma is the most important factor influencing tea consumers' choices along with taste, price, and brand. This study aims to determine how the brewing time and amount of green tea affect the aroma profile of green tea infusion. The effect of the amount of Turkish green tea (5-10 g) and brewing time (5-60 min) on aromatic volatile compounds was evaluated using solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) technique. The SPME/GC-MS analysis identified 57 components in the aroma profile of green tea infusions including 13 esters, 12 alkanes, 7 unknowns, 6 ketones, 3 alcohols, 2 terpenes, 2 terpenoids, 1 alkaloid, 1 phenolic compound, 1 lactone, 1 pyrazine, and 1 norisoprenoid. The green tea amount and brewing time had significant effects on the number of chemical compounds. A total of 42, 47, and 36 aromatic volatile compounds were determined by brewing 5, 7.5, and 10 g of green tea. The most abundant constituents in green tea infusions were phytone, 2-decenal, lauric acid, unknown 1, methoxy-1-methylethyl pyrazine, α-ionone, β-ionone, and diethyl phthalate (DEP). With this study, the aroma structures of green tea infusion have been revealed for the first time depending on the brewing time and quantity.

Acute, dose-response effects of guayusa leaf extract on mood, cognitive and motor-cognitive performance, and blood pressure, heart rate, and ventricular repolarization.

We conducted a randomized, double-blind, placebo-controlled crossover trial in young adults to examine the dose-dependent (600 mg versus 1200 mg), acute effects of consumption of an Ilex guayusa tea extract (GLE) on mood, cognitive and motor-cognitive performance, as well as its acute cardiovascular effects. Twenty-five adults (mean ± SD, age = 28 ± 7 y; 9 M/16 F) completed familiarization and then three randomly ordered experimental visits where they consumed either 600 mg (GLE600) or 1200 mg (GLE1200) GLE or placebo (PLA). Following supplement consumption, participants completed a mood state survey, assessments of perceived jitteriness, energy, and focus, and neurocognitive and motor-cognitive testing. Blood pressure (BP), heart rate, and QT interval length were determined before and after supplementation. GLE600 significantly improved total mood disturbance (mean ± SE difference = -6.9 ± 2.6 au, p = 0.034), fatigue-inertia (-2.84 ± 0.89 au, p = 0.008), perceived energy (+13.00 ± 4.49 au; p = 0.02), motor speed (+4.52 ± 1.42 au, p = 0.008), and psychomotor speed (+7.20 ± 2.16 au, p = 0.005) relative to PLA. GLE1200 also improved psychomotor speed (+5.08 ± 2.16 ms, p = 0.045) and uniquely increased motor-cognitive performance as reflected by a decrease in reaction time (-0.106 ± 0.04 ms, p = 0.026) during a neurocognitive hop test. The effect of GLE on jitteriness was both dose- and sex-dependent. Jitteriness increased with increasing GLE dose in women only (p < 0.001). Both GLE600 and GLE1200 similarly increased systolic and diastolic BP by 4-5 mmHg (p ≤ 0.022). Neither GLE600 nor GLE1200 acutely influenced QTc length (p = 0.31). The goal of GLE supplementation should be considered when selecting a dosing strategy. Lower dosages of GLE (e.g. 600 mg) appear to optimize cognitive and mood-related outcomes while limiting side-effects such as jitteriness in women, and higher dosages may be necessary (e.g. 1200 mg) to promote improvements in motor-cognitive performance.

Root Rot Management in Common Bean (Phaseolus vulgaris L.) Through Integrated Biocontrol Strategies using Metabolites from Trichoderma harzianum, Serratia marcescens, and Vermicompost Tea

Common bean (Phaseolus vulgaris L.) is an essential food staple and source of income for small-holder farmers across Africa. However, yields are greatly threatened by fungal diseases like root rot induced by Rhizoctonia solani. This study aimed to evaluate an integrated approach utilizing vermicompost tea (VCT) and antagonistic microbes for effective and sustainable management of R. solani root rot in common beans. Fourteen fungal strains were first isolated from infected common bean plants collected across three Egyptian governorates, with R. solani being the most virulent isolate with 50% dominance. Subsequently, the antagonistic potential of vermicompost tea (VCT), Serratia sp., and Trichoderma sp. was assessed against this destructive pathogen. Combinations of 10% VCT and the biocontrol agent isolates displayed potent inhibition of R. solani growth in vitro, prompting in planta testing. Under greenhouse conditions, integrated applications of 5 or 10% VCT with Serratia marcescens, Trichoderma harzianum, or effective microorganisms (EM1) afforded up to 95% protection against pre- and post-emergence damping-off induced by R. solani in common bean cv. Giza 6. Similarly, under field conditions, combining VCT with EM1 (VCT + EM1) or Trichoderma harzianum (VCT + Trichoderma harzianum) substantially suppressed disease severity by 65.6% and 64.34%, respectively, relative to untreated plants. These treatments also elicited defense enzyme activity and distinctly improved growth parameters including 136.68% and 132.49% increases in pod weight per plant over control plants. GC–MS profiling of Trichoderma harzianum, Serratia marcescens, and vermicompost tea (VCT) extracts revealed unique compounds dominated by cyclic pregnane, fatty acid methyl esters, linoleic acid derivatives, and free fatty acids like oleic, palmitic, and stearic acids with confirmed biocontrol and plant growth-promoting activities. The results verify VCT-mediated delivery of synergistic microbial consortia as a sustainable platform for integrated management of debilitating soil-borne diseases, enhancing productivity and incomes for smallholder bean farmers through regeneration of soil health. Further large-scale validation can pave the adoption of this climate-resilient approach for securing food and nutrition security.

Let the black tea and green tea take care of your oral health — A short review of the antimicrobial activity of black tea and green tea extracts on

Dental caries is a major global concern and source of great trouble worldwide. It is one of the most common chronic oral diseases in the world that affects both adults and children. The prevalence of DMFT index as a diagnostic criterion in the estimation of dental caries in the age group of 3–18 years was found to be 57%, whereas in patients aged above 18 years, it was much higher that is 77%.Many studies have been carried out all over the world to find the cause behind it, and the main cause, which was well accepted by the people, was the action of pathogenic bacterial microflora such as ( in the oral cavity on the tooth surfaces. These bacteria strongly adhere to the tooth surface and produce lactic acid after fermentation of sucrose and various carbohydrates, which is responsible for the cavitation in the teeth. Many experiments and efforts have been made to remove from the oral cavity, like antibiotics, oral drugs, and more, which are beneficial but have side effects after long-term use, such as vomiting, diarrhea, resistance, teeth staining, etc.That's why search ended at tea which is becoming a popular beverage and a widely consumed drink these days that has anti-streptococcal properties with least of side effect.India's tea usage changed over time from being a colonial export to a regular beverage. With over 29% of the global tea production, India is one of the world's biggest producers and consumers. In India, tea has long been closely linked to the medicinal herbs that have long been used for both therapeutic purposes and general well-being.

Effects of tea infusion on selenium uptake in grapevine

Increased selenium (Se) content in fruits can supply Se in human body, but the effects of teas on the Se uptake in fruit trees are unknown. The effects of infusions of four teas (green, black, dark, and white) on the Se uptake of grapevine were studied to promote the Se uptake in fruit trees in this study. However, only black tea infusion increased the biomass, photosynthetic pigment content, superoxide dismutase (SOD) activity, peroxidase (POD) activity, and soluble protein content of grapevine. Except for white tea infusion, other tea infusions also increased the catalase (CAT) activity of grapevine. Furthermore, the tea infusions increased the activities of adenosine triphosphate sulfurase (ATPS) and adenosine 5’-phosphosulfate reductase (APR), and decreased the activities of serine acetyltransferase (SAT) and selenocysteine methyltransferase (SMT). Only the dark and white tea infusions increased the shoot total Se content by 86.53% and 23.32%, respectively (compared with the control), and also increased the shoot inorganic Se content and shoot organic Se content. Notably, four tea infusions decreased the organic Se proportion and increased the inorganic Se proportion in grapevine. Correlation and grey relational analyses showed that the root total Se content, ATPS activity, and ARP activity were closely associated with the shoot total Se content. The principal component and cluster analyses also showed that the ATPS activity, APR activity, root total Se content, and shoot total Se content were classified into one category. These findings show that black tea infusion can promote grapevine growth, while dark and white tea infusions can promote the Se uptake in grapevine.

Exploring the antioxidant realm of green tea: From extraction to fortification

AbstractGreen tea, a widely consumed beverage with a long history of traditional use has garned renewed scientific interest due to its potential health benefits. Unlike other tea types, green tea undergoes minimal oxidation and thus preserving its potent catechins and antioxidant properties. This review devels into the fascinating chemistry of green tea, exploring how processing steps like fixation and rolling, shape its distinct profile. We will further explore the potential health benefits associated with green tea consumption, acknowledging the existing research focus on tea polyphenols and aiming to provide a broader perspective on its potential health impact. Finally, the review examines the emerging application of green tea extract fortification in food matrices. This innovative approach offers exciting possibilities for enhancing food stability and sensory appeal while potentially contributing to a range of health benefits.

Exploring the relationship between color and taste: Unveiling critical color and taste compounds of Qingxiang Tieguanyin tea infusion

The color and taste of tea infusion play crucial roles in assessing tea quality. While color can be easily quantified, taste perception is subjective in nature. Can the color of tea infusion directly reflect its taste? In this study, spectroscopy and metabolomics techniques combined with machine learning algorithms, were used to identify the key compounds that responsible for both color and taste in Qingxiang Tieguanyin (QXTGY) tea infusion. The results showed strong correlations between almost all of 46 differential compounds and the taste profile of the tea infusion. Notably, quercetin 3-O-glucosyl rutinoside, rutin, and quercetin 3-O-glucoside were found to establish a connection between the color and taste of QXTGY tea infusion. Specifically, within a certain range, these compounds promoted a darker color (deepening the yellowness) in the tea infusion while simultaneously reducing its umami and brisk taste. This indicates that the color of tea infusion can reflect its taste to some extent. Furthermore, quercetin 3-O-glucosyl rutinoside had the most significant impact on the color of the tea infusion. The findings of this study offer an alternative objective approach to evaluate the taste of tea infusion by objectively determining its color.

A Comparative Study of the Effect Coffee and Tea on Some Parameters in the Rats Blood

Abstract Background: Tea and coffee have been consumed since decade ago and became a significant part of social life and cultural traditions. Objective: The study aims to evaluate the effects of coffee and black tea extract on some blood factors in adult albino rats. Materials and Methods: Eighteen adult male albino rats, classified into three groups of six: group 1 (control) received orally drinking water only, group 2 (tea) received orally extract tea, group 3 (coffee) treated orally with coffee. Coffee and tea extracts were prepared daily at a dose of 30 g/L and provided at all times to the rats for 30 day as drinking water. Iron and ferritin levels, cholesterol concentration of low-density lipoprotein (LDL) and high-density lipoprotein (HDL), superoxide dismutase (SOD), glutathione peroxidase (GPx) activities as well as the levels of tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) were compared among these groups. Results: This study inferred, there was a significant decrease the amount of iron in the blood as well as the ferritin. Also consumption of coffee or tea lowers LDL cholesterol and HDL cholesterol and enhanced antioxidant activity by SOD and GPx enzymes more than control group. Furthermore, increased these levels in proinflammatory cytokines (IL-6 and TNF-α) in treated rats with tea and coffee extract more than their levels in the control group. Conclusion: The extracts of tea and coffee lowered the iron and ferritin concentration, have remarkable antioxidant activity, and increased the levels in proinflammatory cytokines (IL-6 and TNF-α) in the rat blood.

Comparative evaluation of minimal inhibitory concentration and minimal bactericidal concentration of various herbal irrigants against Enterococcus faecalis.

The purpose of this article is to evaluate the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of Herbal Irrigants. The aim of the study was to evaluate MIC and MBC of herbal extracts of Azadirachta indica, Curcuma longa, and Green Tea Against Enterococcus faecalis. The MIC and MBC of extracts of A . indica (neem), C. longa (turmeric), and Green Tea were evaluated to establish them as standard root canal irrigants against E. faecalis using agar well diffusion method. The collected data were statistically analyzed using the Statistical Package for the Social Sciences (SPSS) software. The present study found that green tea exhibited the most substantial antimicrobial activity among the tested herbal extracts, which was comparable to chlorhexidine. Although A. indica and C. longa required higher concentrations for effectiveness, their antimicrobial properties were also apparent. Within the constraints of this study, it can be concluded that green tea could be considered a promising alternative to chlorhexidine in treating endodontic infections due to its substantial antimicrobial activity against E. faecalis at lower concentrations.

Junshanyinzhen tea extract prevents obesity by regulating gut microbiota and metabolic endotoxemia in high-fat diet fed rats

Obesity is associated with gut dysbiosis and metabolic endotoxin. Junshanyinzhen tea extract (JSTE) reduced fat accumulation and body weight in obese mice. However, the effects and mechanism of JSTE in preventing obesity were unclear. Therefore, we used different doses of JSTE (75, 150 and 300 mg/(kg∙d)) to evaluate the effect on high-fat diet (HFD)-induced rats under 8 weeks of intervention. Here, our results showed that JSTE could significantly reduce body weight gain, blood lipid levels and fat accumulation, improve fatty damage in liver tissue (P < 0.05). In addition, JSTE increased the expression of intestinal tight junction proteins (P < 0.05), relieved metabolic endotoxemia (P < 0.05) and chronic low-grade inflammation in HFD rats. Sequencing of fecal samples showed that JSTE could effectively reverse the microbial diversity and the ratio of Firmicutes to Bacteroidetes to normal levels in HFD-fed rats. Desulfovibrioceae and Erysipelotrichaceae, which are positively related to obesity, were decreased by JSTE intervention (P < 0.05). while Bifidobacteriaceae, Bacteroidaceae, Akkermansia, and Clostridium, which are negatively related to obesity, were increased. Together, these results suggested that JSTE might effectively prevent obesity by modulating gut microbiota dysbiosis, intestinal barrier dysfunction, metabolic endotoxemia and chronic low-grade inflammation in HFD-induced rats.

Improved Gut Health by a Green Tea Extract Confection in Metabolic Syndrome and Healthy Adults Occurred Without Affecting Short-Chain Fatty Acids and Microbiota Diversity

Improved Gut Health by a Green Tea Extract Confection in Metabolic Syndrome and Healthy Adults Occurred Without Affecting Short-Chain Fatty Acids and Microbiota Diversity

Effect of Chlorhexidine Gluconate (0.2%), Combination (0.2% Chlorhexidine and 0.05% Sodium Fluoride), and Green Tea Extract (0.5%) Mouth Rinses on Colony Count Changes of Streptococcus mutans and Lactobacillus in Saliva – A Randomized Controlled Trial

Abstract Introduction Streptococcus mutans and Lactobacillus acidophilus are the well-known etiological factors for dental caries. Chlorhexidine (CHX) gluconate is the “gold-standard” antimicrobial agent but having adverse effects such as brown staining of the teeth and altered taste. Thus, there is a need for an alternative herbal product. Objective This study was done to compare the efficacy of CHX gluconate (0.2%) and combination (0.2% CHX and 0.05% sodium fluoride [NaF]) mouth rinses to that of green tea extract (0.5%) mouth rinse in reducing the salivary count of S. mutans and L. acidophilus in dental students. Materials and Methods The sample size of the study was 75 dental students with ≥4 decayed, missing, and filled teeth (DMFT) index. They were divided into three equal groups to test various mouth rinses against S. mutans and Lactobacillus. Unstimulated salivary samples were collected at baseline and postrinse (14 days) and tested for the colony-forming units of S. mutans and Lactobacillus. The Chi-square test was used to ascertain the demographic characteristics of the study population. One-way ANOVA statistics and paired t-test were applied to calculate the inferential statistics between the variables. The statistical constant was fixed at P &lt; 0.05. Results The results of the study indicated that there was a statistically significant reduction in S. mutans and Lactobacilli count in all the three study groups. Conclusion Green tea mouth rinse can be a promising preventive therapy worldwide for the prevention of dental caries but CHX mouthwashes are superior in reduction of S. mutans and Lactobacillus.

Green Synthesis of Antimicrobial Silver Nanoparticles using Green Tea Extract: The Role of Concentration and pH

ABSTRACTGreen synthesis for silver nanoparticles (AgNPs) is the process of reducing Ag+ ions to Ag0 by using plant bioactive compounds. Green synthesis is safer, environmentally friendly and cost-effective. Plant bioactive compounds from Camellia sinensis L. (green tea) extract containing polyphenols can be used as a reducer in the formation of silver nanoparticles. This study aims to determine the effect of pH (8, 9, and 10), at 1,5mM AgNO3 concentration and 0,75% green tea extract concentration on the physical characteristics and antibacterial activity of silver nanoparticles prepared by green synthesis method. The synthesized results were evaluated by UV-Vis Spectrophotometer, Dynamic Light Scattering (DLS), SEM, and FTIR. The optimal AgNP synthesis process resulted from the AgNO3 concentration of 1.5 mM with 0.75% green tea extract at pH 10 which showed an absorbance value of 4,420 at λ 435,3 nm, with a particle size of 47,1 nm and a PDI of 0,243. The formation of AgNPs was observed by a change in color to brownish yellow. Antibacterial activity of AgNPs using liquid diffusion method. The results obtained AgNPs for Staphylococcus aureus bacteria has had inhibition at a concentration of 0,187mM and Escherichia coli at a concentration of 0,375mM.Keywords: Silver nanoparticles; green synthesis; green tea extract; pH; antibacterial activity

Malodor Control Effect by Using Dentifrice Containing Sodium Monofluorophosphate, Sodium Pyrophosphate, Green Tea Extract and Dental Type Silica

Malodor Control Effect by Using Dentifrice Containing Sodium Monofluorophosphate, Sodium Pyrophosphate, Green Tea Extract and Dental Type Silica

Green tea extracts clinical examination in humans’ wounds healing process: A case study

Green tea extracts clinical examination in humans’ wounds healing process: A case study

Biological Activity and Phenolic Content of Kombucha Beverages under the Influence of Different Tea Extract Substrates

Biological Activity and Phenolic Content of Kombucha Beverages under the Influence of Different Tea Extract Substrates

Investigation of the quality of Lu'an Guapian tea during Grain Rain period by sensory evaluation, objective quantitative indexes and metabolomics

The harvest date is a crucial factor in determining tea quality. For Lu'an Guapian (LAGP) tea, Grain Rain period (GRP) represents a pivotal phase in the transformation of tea quality. The sensory evaluation, computer vision and E-tongue revealed that the liquor color score, B and G values of tea infusion were increased during GRP, while the astringency, bitterness intensities and the R value of the tea infusion were decreased. Consequently, the tea infusion exhibited a greener hue and the taste became appropriate during GRP. Non-targeted metabolomics revealed that the majority of amino acids and derivatives was reduced during GRP. Furthermore, flavonoids, in particular flavonol glycosides, exhibited considerable variation during GRP. Finally, nine metabolites were identified as markers for quality transformation during GRP by PLS and Random Forest. This study investigated the quality of LAGP teas during GRP and filled the gap in the variation of LAGP tea quality during GRP.

Analysis of pivotal compounds in NanLuShuiXian tea infusion that connect its color and taste

The infusion color and taste serve as pivotal benchmarks reflecting the quality of tea, yet the specific compounds responsible for the distinctive color and taste of the NanLuShuiXian (NLSX) tea infusion remain unknown. In this study, colorimetry, spectroscopy, and quantitative descriptive analysis (QDA) were employed to quantify the color and taste of 10 NLSX tea infusions. Furthermore, metabolomics techniques combined with correlation analysis were used to identify the key color and taste compounds and explore the relationship among color, taste, and compounds in NLSX tea infusion. The results showed that a total of 78 compounds were identified. It was observed that both the color and taste features of NLSX tea infusion and its metabolites exhibited certain patterns of variation. Within a certain range, heightened concentrations of carthamidin diglucoside isomer 2, theanine, and quercetin 3-O-caffeyl-glucoside within NLSX correlate inversely with the levels of 4′-methyl-epigallocatechin (4′-methyl-EGC), ellagic acid, quercetin, camellikaempferoside C isomer 1, and chicoric acid. This competitive relationship among metabolites corresponded to a lighter infusion color and a fresher and sweeter taste. Conversely, decreased carthamidin diglucoside isomer 2, theanine, and quercetin 3-O-caffeyl-glucoside in NLSX will lead to a deeper infusion color and diminish taste quality.

Effect of tea extract (Camellia sinensis) on shelf life and intrinsic quality of tempe

Tempe is Indonesian traditional food made from fermented soybeans. Tempe has a short shelf life due to its high moisture content and the activity of microorganisms. The shelf life of tempe can be increased by using tea extract in tempe processing because tea contains antioxidant and antimicrobial components. This research aims to evaluate the effect of using tea extract in tempe processing on the shelf life, physicochemical characteristics, and sensory profile of tempe. During storage, the shelf-life test used the descriptive observation method on the colour, flavour, taste, and texture. The use of 0.5% black tea extract in the initial soaking of soybeans can increase the shelf life of tempe to 4 and 6 days at room and refrigerator temperature, respectively. The result showed that tempe had significantly (p&lt;0.05) lower ash content (0.81% wb), brightness (65.37), and pH (6.50), while the texture (15.3 Kg force) was significantly higher (p&lt;0.05) than the control (untreated tempe). The results of sensory evaluation using the hedonic rating test showed that fresh tempe with black tea extract treatment had significantly lower (p&lt;0.05) colour, texture, and overall attributes than the control one. The same evaluation on fried tempe showed that the black tea extract treatment significantly increased (p&lt;0.05) the texture attribute compared to the control.

Green synthesis structural, morphological and sonocatalytic properties of CuO nanoparticles assisted by Camellia sinensis (Tea) extract

In this green synthesis approach for copper oxide (CuO) nanoparticles (NPs), the reducing agent obtained from Camellia sinensis (Tea) extract was used. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), ultraviolet visible (UV-Vis) spectroscopy, field emission scanning electron microscope (FESEM) with energy-dispersive X-ray (EDX), high resolution transmission electron microscope (HRTEM) and Selected Area Electron Diffraction (SAED) techniques were used for as-prepared sample characterization. From XRD result, the crystallite size estimated by Scherrer method was found to be 35 nm. Morphological results reveals that the CuO NPs possesses small particle size with the range of 40–45 nm, led to high surface area, which enhances the absorption of more number of dye molecules, which results in high degradation efficiency. Present work reveals that degradation of malachite green (MG) dye in aqueous solutions under sonocatalytic treatment. CuO NPs exhibit excellent degradation efficiency against MG dye (95 % removal in 70 min). Moreover, the rate constant for the degradation efficiency was investigated with pseudo- first and second order kinetics. Moreover, CuO NPs possesses potential antibacterial activity against human pathogens such as Gram-positive (Staphylococcus pyogenes) and Gram-negative (Pseudomonas aeruginosa).