Insight into the sorption and desorption pattern of pyrrolizidine alkaloids and their N-oxides in acidic tea (Camellia sinensis) plantation soils.

Pyrrolizidine alkaloids (PAs) and their N-oxides (PANOs) are phytotoxins produced by various plant species and have been emerged as environmental pollutants. The sorption/desorption behaviors of PAs/PANOs in soil are crucial due to the horizontal transfer of these natural products from PA-producing plants to soil and subsequently absorbed by plant roots. This study firstly investigated the sorption/desorption behaviors of PAs/PANOs in tea plantation soils with distinct characteristics. Sorption amounts for seneciphylline (Sp) and seneciphylline-N-oxide (SpNO) in three acidic soils ranged from 2.9 to 5.9 µg/g and 1.7 to 2.8 µg/g, respectively. Desorption percentages for Sp and SpNO were from 22.2% to 30.5% and 36.1% to 43.9%. In the mixed PAs/PANOs systems, stronger sorption of PAs over PANOs was occurred in tested soils. Additionally, the Freundlich models more precisely described the sorption/desorption isotherms. Cation exchange capacity, sand content and total nitrogen were identified as major influencing factors by linear regression models. Overall, the soils exhibiting higher sorption capacities for compounds with greater hydrophobicity. PANOs were more likely to migrate within soils and be absorbed by tea plants. It contributes to the understanding of environmental fate of PAs/PANOs in tea plantations and provides basic data and clues for the development of PAs/PANOs reduction technology.

The effect of Camellia sinensis ointment on perineal pain and episiotomy wound healing in primiparous women: A triple-blind randomized clinical trial.

BACKGROUND AND OBJECTIVE: Episiotomy is one of the most commonly performed procedures in obstetrics. complications of episiotomy are pain, bleeding, infection, pain in the sitting position, and difficulty in taking care of the baby. This study aimed to investigate the effect of Camellia sinensis ointment on perineal pain and episiotomy wound healing in primiparous women. METHODS: This triple-blinded randomized clinical trial was conducted on 60 primiparous women who were referred to the maternity ward of Al-Hadi hospital in Shoushtar and Ganjovian hospital in Dezful, Iran, from 2020 to 2021. Participants were randomly assigned into two groups of intervention (Camellia sinensis extract ointment) and control (placebo) with a follow-up of 14 days. REEDA scale (redness, edema, ecchymosis, discharge, and approximation) was used to measure wound healing and the Visual Analog Scale (VAS) was used to measure the pain intensity. RESULTS: There was no significant difference between two groups before intervention in terms of sociodemographic characteristics, pain intensity, and episiotomy wound status. Scores of pain intensity and wound healing reduced on days 7, 10, and 14 post-intervention in the intervention group compared to placebo. There was a significant decrease between the groups of intervention and control in terms of the mean score of pain intensity (VAS scale) on day 10 (1.33 ± 0.71, 1.77 ± 0.93) and day 14 (0.73 ± 0.74, 1.13 ± 0.81) post-intervention (P < 0.05). Also, on day 14 post-intervention, there was a significant decrease between the groups of intervention and control in terms of the mean score of episiotomy wound healing (REEDA index) (0.53 ± 0.77, 1.77 ± 1.46) (P < 0.05). The GLM test was applied for repeated measures. REEDA index and VAS scale changed during different times (time-variable) (p < .001). But, the studied groups (group variable) and the studied groups (interaction effect of group * time) did not affect the changes in the REEDA index (p = .292, p = .306) and VAS scale (p = .47) during different times. CONCLUSION: Our study showed that Camellia sinensis extract ointment has a small effect on the healing process and pain reduction of episiotomy wounds. to confirm its effect, a study with a larger sample size should be conducted. TRIAL REGISTRATION: This trial was registered in the Iranian Registry of Clinical Trials on 04/10/2019 with the IRCT ID: IRCT20190804044428N1. Participants were enrolled between 11 April 2020 and 20 January 2021. URL of registry: https://en.irct.ir/trial/41326.

Ovicidal activity and cytotoxicity of ethanolic extract of turmeric (Curcuma longa) and green tea (Camellia sinensis) to treat digestive parasite of sheep.

Background: The Trichuris eggs are collected from naturally infected sheep. Natural antihelmintics such as herbal medicines are needed as an alternative, such as natural compounds from endemic plants. Aim: This present study aims to evaluate the ovicidal activity and cytotoxicity effects of ethanolic extract of Curcuma longa (EECL) and Camelia sinensis (EECS) as a biological anthelmintic against the egg of Trichuris sp. Methods: The Trichuris eggs are collected from naturally infected sheep. CMC-Na solution 1% was used as a control. The treatments were 0.12% EECL; 0.24% EECL; 0.15% EECS; 0.30% EECS; a combination of 0.12% EECL and 0.30% EECS; a combination of 0.24% EECL; and 0.15% EECS. Ovicidal activity testing by microscopic examination of eggs treated using different concentrations of EECL extract, EECS, and a combination of them. They were exposed for various times (7, 14, 21, and 28 days) and incubated at room temperature. Results: The study shows that a combination of C. longa extract and tea extract exhibits good ovicidal anthelmintic activity against Trichuris sp. in sheep. Cytotoxicity examination using the 3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyl tetrazolium bromide (MTT) test. Based on MTT data processed using regression analysis, the obtained LC50 from the administration of EECL, EECS, and a combination of both in a ratio of 1:1, 2:2, 1:2, and 2:1. The combination of EECL extract and EECS with the highest concentration produced cell viability of 28.46%, 17.25%, 56.01%, and 46.47%, respectively. Conclusion: It can be concluded that the most cytotoxic ingredient is found in the combination of EECL and EECS (2:2) at 17.25% and the safest is in the ratio (1:2) at 56.01%.

Interactive Effects of Arabinoxylan Oligosaccharides and Green Tea Polyphenols on Obesity Management and Gut Microbiota Modulation in High-Fat Diet-Fed Mice.

Dietary fiber and polyphenols have been shown to possess antiobesity properties. However, their combined effects need further investigation. This study investigated the individual and combined effects of arabinoxylan oligosaccharides (AXOS) from rice bran and green tea polyphenols (GTP) in high-fat diet-induced obese mice. We found that the combination of AXOS and GTP (A + G) significantly reduced overall fat mass and improved lipid profiles, although the effects were not synergistic. AXOS and GTP regulated lipid metabolism in different tissues and exhibited counteractive effects on gut microbiota. AXOS decreased α diversity and promoted Bifidobacterium, with GTP counteracting these effects. In vitro fermentation confirmed that GTP counteracted AXOS-induced microbiota changes in a dose-dependent manner. This study highlights the potential of tailored combinations of dietary fiber and polyphenols to treat obesity while considering their complex microbial interplay.

Sustainable regulation of calcium magnesium phosphate and rapeseed cake on soil-tea system in Mount Lushan, China.

Lushan Yunwu tea quality is limited by soil acidity and sterility. This article examined a 3-year localization experiment at 1100 m altitude to demonstrate the sustainable management of conditioners, calcium magnesium phosphate (P), rapeseed cake (C), and combination application (P + C) by one-time application on the soil-tea system in Mount Lushan. The study found that conditioners (P, C, P + C) reduced soil acidification and maintained a pH of 4.75-5.34, ideal for tea tree development for 3 years. Phosphorus activation coefficient (PAC), nitrogen activation coefficient (NAC), and organic matter (OM) content were significantly higher (P < 0.05) in the first year after conditioner treatment, with P + C being the best. After P + C, PAC, NAC, and OM rose by 31.25%, 47.70%, and 10.06 g kg-1 compared to CK. In comparison to the CK, tea's hundred-bud weight (BW), free amino acids (AA), tea polyphenols (TPC), and chlorophyll (Chl) content of P + C treatment got 29.98%, 14.41%, 22.49%, and 28.85% increase compared to that of the CK, respectively. In the second year, the three treatments of P, C and P + C still had significant moderating effects on the physicochemical properties of the soil and the quality indexes of the tea leaves. The PAC of the soil under the three treatments increased by 0.06%, 0.07% and 0.18%, respectively, as compared to the control.P + C increased BW, AA, TPC and Chl of tea for 2 years. Three conditioners had 2-year regulatory impacts on soil fertility indicators, tea output, and quality. C and P + C both increased soil OM by 18.59% and 21.78% compared to CK in the third year, outperforming P treatment. Redundancy analysis revealed that the primary physicochemical factors influencing tea output and quality were soil OM and pH, with available phosphorus, urease, acid phosphatase, and available nitrogen following closely afterwards.

Pruned tea biomass plays a significant role in functional food production: A review on characterization and comprehensive utilization of abandon-plucked fresh tea leaves.

Tea is the second largest nonalcoholic beverage in the world due to its characteristic flavor and well-known functional properties in vitro and in vivo. Global tea production reaches 6.397 million tons in 2022 and continues to rise. Fresh tea leaves are mainly harvested in spring, whereas thousands of tons are discarded in summer and autumn. Herein, pruned tea biomass refers to abandon-plucked leaves being pruned in the non-plucking period, especially in summer and autumn. At present, no relevant concluding remarks have been made on this undervalued biomass. This review summarizes the seasonal differences of intrinsic metabolites and pays special attention to the most critical bioactive and flavor compounds, including polyphenols, theanine, and caffeine. Additionally, meaningful and profound methods to transform abandon-plucked fresh tea leaves into high-value products are reviewed. In summer and autumn, tea plants accumulate much more phenols than in spring, especially epigallocatechin gallate (galloyl catechin), anthocyanins (catechin derivatives), and proanthocyanidins (polymerized catechins). Vigorous carbon metabolism induced by high light intensity and temperature in summer and autumn also accumulates carbohydrates, such as soluble sugars and cellulose. The characteristics of abandon-plucked tea leaves make them not ideal raw materials for tea, but suitable for novel tea products like beverages and food ingredients using traditional or hybrid technologies such as enzymatic transformation, microbial fermentation, formula screening, and extraction, with the abundant polyphenols in summer and autumn tea serving as prominent flavor and bioactive contributors.

LC-MS and GC-MS based metabolomics analysis revealed the impact of tea trichomes on the chemical and flavor characteristics of white tea.

To explore the influence of tea trichomes on the quality of white tea, liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS), and headspace solid phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) were used to identify non-volatile and volatile compounds white tea without trichomes (WTwt) and pure trichomes (PT). It was found that the bitter and astringent compounds, caffeine (CAF), epigallocatechin gallate (EGCG), epicatechin gallate (ECG) and flavonol glycosides, were mainly enriched in the WTwt, with 16.3-fold, 47.1-fold and 28.7-fold decrease in CAF and EGCG and ECG, respectively, and the content of these compounds in PT were lower than the taste thresholds. In PT, kaempferol-3-O-(p-coumaroyl)-glucoside and kaempferol-3-O-(di-p-coumaroyl)-glucoside were non-volatile marker compounds, and decanal was significant aroma contributor with rOAV = 250.86. Moreover, the compounds in trichomes mainly contributed to the fruity and floral aroma of white tea, among which benzyl alcohol, (E)-geranylacetone, decanal, dodecanal and 6-methyl-5-hepten-2-one were the crucial aroma components, which were 2.1, 1.7, 1.8, 1.4 and 2.2 times as much as the WTwt in the PT, respectively. In conclusion, trichomes can improve the quality of white tea by reducing the bitterness and astringency, increasing the umami, as well as enhancing the fruity and floral aromas.

Analysis and classification of tea varieties using high-performance liquid chromatography and global retention models.

As a result of their metabolic processes, medicinal plants produce bioactive molecules with significant implications for human health, used directly for treatment or for pharmaceutical development. Chromatographic fingerprints with solvent gradients authenticate and categorise medicinal plants by capturing chemical diversity. This work focuses on optimising tea sample analysis in HPLC, using a model-based approach without requiring standards. Predicting the gradient profile effects on full signals was the basis to identify optimal separation conditions. Global models characterised retention and bandwidth for 14 peaks in the chromatograms across varied elution conditions, facilitating resolution optimisation of 63 peaks, covering 99.95 % of total peak area. The identified optimal gradient was applied to classify 40 samples representing six tea varieties. Matrices of baseline-corrected signals, elution bands, and band ratios, were evaluated to select the best dataset. Principal Component Analysis (PCA), k-means clustering, and Partial Least Squares-Discriminant Analysis (PLS-DA) assessed classification feasibility. Classification limitations were found reasonable due to tea processing complexities, involving drying and fermentation influenced by environmental conditions.

Comparison of microtensile bond strength of prepared teeth treated with proanthocyanidin, Camellia sinensis - Polyphenols, and metal crowns luted with resin-modified glass ionomer cement: An in vitro study.

AIM: The aim of this study was to evaluate the effect of proanthocyanidin and C. sinensis-polyphenols on microtensile bonding properties of prepared teeth with resin-modified glass ionomer cement (GIC). SETTING AND DESIGN: This was an in vitro study. MATERIALS AND METHODS: Seventy-eight maxillary premolars were selected and mounted into auto-polymerizing acrylic resin blocks. The samples were prepared and metal crowns were fabricated. The samples were randomly divided into three groups. Samples under Group 1 were not treated with any of the extracts and followed conventional bonding protocol. Samples under Group 2 and Group 3 were treated with proanthocyanidin and C. sinensis-polyphenols, respectively. After dentin treatment, these samples were luted to metal crowns using resin-modified GIC. Universal testing machine was used to measure the load at which the crowns were debonded and microtensile bond strength in MPa was calculated. STATISTICAL ANALYSIS: The results were statistically analyzed using one-way ANOVA and post hoc Tukey HSD. RESULTS: Samples treated with C. sinensis polyphenols (Group 3) had maximum bond strength followed by Group 2, where the samples were treated with proanthocyanidin. CONCLUSION: C. sinensis polyphenols due to their anti-proteolytic and antioxidant properties showed improved bond strength compared to proanthocyanidin, a cross-linking agent, followed by conventional bonding protocol.

Systematic review assessing the effects of amendments on acidic soils pH in tea plantations.

Soil acidification has emerged as a critical limiting factor for the sustainable development of the tea industry. In this article, a comprehensive review of 63 original research articles focusing on the impact of amendments on the pH in tea plantations soil was conducted. Through meta-analysis, the effect of applying soil amendments to increase the pH of tea plantation soil and its influencing factors were investigated. The results revealed that lime had a significant impact, increasing the pH by 18% in tea plantation soil, while rapeseed cake had a minimal (2%) effect. It was observed that as the quantity of amendments and pH levels increased, so did their impact on the pH of tea plantation soil. Subgroup analysis within biochar showed varying effects, depending on soil pH, with an 11% increase in acidic soil. Among these amendments, biochar produced at pyrolysis temperature ranging from 501-600 °C and derived from animal waste demonstrated significant effect on increasing soil pH in tea plantations by 9% and 12%, respectively. This study offers valuable insights into improving and ensuring the health and sustainability of tea plantations.

Efficacy of green tea ( Camellia sinensis Linn) 3% extract cream on improvement of striae distensae.

Background: Striae distensae (SD) is a skin condition that frequently causes dermatological consultations and although asymptomatic, it may can cause itch and burning sensation. Green tea extract contains polyphenol, including flavanol, flavandiol, flavonoid, phenolic acid, amino acids and minerals which play a role in the repair of stretch marks through anti-inflammatory mechanism, increase collagen production, fibroblast proliferation, and skin hydration. Objective: To determine the efficacy of green tea extract cream on striae distensae. Methods: This is a pre-experimental clinical trial with a pretest-posttest design on 36 subjects with striae distensae. Diagnosis establishes through history taking and clinical evaluation. Imam Nelva Alviera (INA) score was used as SD severity before and after the application of the 3% green tea extract cream carried out at weeks 0, 2, 4, 6, and 8. Side effects and subjects' satisfaction were also recorded. Cochran test was carried out to see the difference before and after treatment, with a p-value <0.05 considered significant. Results: Majority of study subjects were 18-25 years (77.8%), had history of pregnancy (75%), had a history of menarche at the age of 12 years (27.8%) and all subjects had striae alba. There was significant decrement in INA score for striae distensae (p<0.001) after eight weeks administration of 3% green tea extract cream. Clinical improvement and no side effects were also noted. All subjects were satisfied. Conclusions: The use of 3% green tea extract cream can improve the appearance of SD.

Theanine Capture of Reactive Carbonyl Species in Humans after Consuming Theanine Capsules or Green Tea.

Acrolein (ACR), methylglyoxal (MGO), and glyoxal (GO) are a class of reactive carbonyl species (RCS), which play a crucial role in the pathogenesis of chronic and age-related diseases. Here, we explored a new RCS inhibitor (theanine, THE) and investigated its capture capacity on RCS in vivo by human experiments. After proving that theanine could efficiently capture ACR instead of MGO/GO by forming adducts under simulated physiological conditions, we further detected the ACR/MGO/GO adducts of theanine in the human urine samples after consumption of theanine capsules (200 and 400 mg) or green tea (4 cups, containing 200 mg of theanine) by using ultraperformance liquid chromatography-time-of-flight-high-resolution mass spectrometry. Quantitative assays revealed that THE-ACR, THE-2ACR-1, THE-MGO, and THE-GO were formed in a dose-dependent manner in the theanine capsule groups; the maximum value of the adducts of theanine was also tested. Furthermore, besides the RCS adducts of theanine, the RCS adducts of catechins could also be detected in the drinking tea group. Whereas, metabolite profile analysis showed that theanine could better capture RCS produced in the renal metabolic pathway than catechins. Our findings indicated that theanine could reduce RCS in the body in two ways: as a pure component or contained in tea leaves.

Dynamic changes and the effects of key procedures on the characteristic aroma compounds of Lu'an Guapian green tea during the manufacturing process.

As a kind of green tea with unique multiple baking processes, the flavor code of Lu'an Guapian (LAGP) has recently been revealed. To improve and stabilize the quality of LAGP, further insight into the dynamic changes in odorants during the whole processing is required. In this study, 50 odorants were identified in processing tea leaves, 14 of which were selected for absolute quantification to profile the effect of processes. The results showed that spreading is crucial for key aroma generation and accumulation, while these odorants undergo significant changes at the deep baking stage. By adjusting the conditions of the spreading and deep baking, it was found that low-temperature (4 °C) spreading for 6 h and low-temperature with long-time baking (final leaf temperature: 102 °C, 45 min) could improve the overall aroma quality. These results provide a new direction for enhancing the quality of LAGP green tea.

Distribution characteristics of potentially toxic metal(loid)s in the soil and in tea plant (Camellia sinensis).

Potentially toxic metal(loid) assessment of tea and tea garden soil is a vital guarantee of tea safety and is very necessary. This study analyzed the distribution of seven potentially toxic metal(loid)s in different organs of the tea plants and soil at various depths in the Yangai tea farm of Guiyang City, Guizhou Province, China. Although soil potentially toxic metal(loid) in the study area is safe, there should be attention to the health risks of Cu, Ni, As, and Pb in the later stages of tea garden management. Soil As and Pb are primarily from anthropogenic sources, soil Zn is mainly affected by natural sources and human activities, and soil with other potentially toxic metal(loid) is predominantly from natural sources. Tea plants might be the enrichment of Zn and the exclusion or tolerance of As, Cu, Ni, and Pb. The tea plant has a strong ability for absorbing Cd and preferentially storing it in its roots, stems, and mature leaves. Although the Cd and other potentially toxic metal(loid)s content of tea in Guizhou Province is generally within the range of edible safety, with the increase of tea planting years, it is essential to take corresponding measures to prevent the potential health risks of Cd and other potentially toxic metal(loid)s in tea.

Facile synthesis of iron nanoparticles from Camellia Sinensis leaves catalysed for biodiesel synthesis from Azolla filiculoides.

Recent years have seen an increase in research on biodiesel, an environmentally benign and renewable fuel alternative for traditional fossil fuels. Biodiesel might become more cost-effective and competitive with diesel if a solid heterogeneous catalyst is used in its production. One way to make biodiesel more affordable and competitive with diesel is to employ a solid heterogeneous catalyst in its manufacturing. Based on X-ray diffraction (XRD) and Fourier Transform infrared spectroscopy (FTIR), the researchers in this study proved their hypothesis that iron oxide core-shell nanoparticles were generated during the green synthesis of iron-based nanoparticles (FeNPs) from Camellia Sinensis leaves. The fabrication of spherical iron nanoparticles was successfully confirmed using scanning electron microscopy (SEM). As a heterogeneous catalyst, the synthesised catalyst has shown potential in facilitating the conversion of algae oil into biodiesel. With the optimal parameters (0.5 weight percent catalytic load, 1:6 oil-methanol ratio, 60 °C reaction temperature, and 1 h and 30 min reaction duration), a 93.33% yield was attained. This may be due to its acid-base property, chemical stability, stronger metal support interaction. Furthermore, the catalyst was employed for transesterification reactions five times after regeneration with n-hexane washing followed by calcination at 650 °C for 3 h.

Pesticide application behavior in green tea cultivation and risk assessment of tea products: a case study of Rizhao green tea.

Previous research on pesticides in green tea mainly focused on detection technology but lacked insights into pesticide use during cultivation. To address this gap, a survey was conducted among Rizhao green tea farmers. The survey results showed that most tea farmers were approximately 60 years old and managed small, scattered tea gardens (< 0.067 ha). Notably, tea farmers who had received agricultural training executed more standardized pesticide application practices. Matrine and thiazinone are the most used pesticides. A total of 16 types of pesticides were detected in the tested green tea samples, with 65% of the samples containing residues of at least one pesticide. Notably, higher levels of residues were observed for bifenthrin, cyfluthrin, and acetamiprid. The presence of pesticide residues varied significantly between seasons and regions. The risk assessment results indicated that the hazard quotient (HQ) values for all 16 pesticides detected in green tea were < 1, suggesting that these residue levels do not pose a significant public health concern.

Large-leaf yellow tea protein derived-peptides alleviated dextran sodium sulfate-induced acute colitis and restored intestinal microbiota balance in C57BL/6 J mice.

Large-leaf yellow tea (LYT)-derived peptides (TPP) are rich in amino acids required for damage repair, such as Glu, Arg, and Pro, and can be used to alleviate acute colitis. However, its effect and mechanisms against colitis remain unclear. This study utilized TPP to intervene in dextran sodium sulfate-induced acute colitis in C57BL/6 J mice. Results confirmed that TPP ameliorated acute colitis symptoms by inhibiting pro-inflammatory cytokines, restoring gut microbiota dysbiosis, particularly by increasing the abundance of beneficial bacteria Akkermansia and Lactobacillus while declining harmful microbiota Escherichia-Shigella. Besides, TPP intervention reshaped the gut microbiota phenotype by increasing the aerobic phenotype and reducing the potentially pathogenic phenotype. Levels of short-chain fatty acids, including acetic acid, propanoic acid, isobutyric acid, and butyric acid, were also enhanced in a dose-dependent manner to help restore gut microbiota equilibrium. This study supports using TPP as a viable plant protein-derived dietary resource for alleviating inflammatory bowel disease.

The potential protective effect of Camellia Sinensis in mitigating monosodium glutamate-induced neurotoxicity: biochemical and histological study in male albino rats.

Monosodium glutamate (MSG) is the sodium compound derived from glutamic acid. Excessive daily ingestion of MSG leads to elevated amounts of glutamic acid in the bloodstream, which can be detrimental to brain structures. Camellia sinensis, often known as green tea (GT), is a rich source of essential hexogen antioxidants that are necessary for the body. Thirty-two adult male albino rats were divided into four groups (n = 8). Group 1 served as a control -ve group. Group 2 was given GT (1.5 ml/rat/day). Group 3 was given MSG (600 mg/kg/day). Group 4 was given MSG (600 mg/kg/day) and GT (1.5 ml/rat/day). All treatments were given orally for 28 days. MSG administration resulted in significant neurotoxicity in rats that was revealed by the significant reduction of serum concentration of glutathione peroxidase (GPx) and nitric oxide (NO), and the significant elevation of total antioxidant capacity (TAC) accompanied by the significant reduction of levels of serum monoamines (dopamine, serotonin, and norepinephrine) and histological changes in the hippocampus area CA1, dentate gyrus, and cerebellar cortex and positive immunohistochemical staining of glial fibrillary acidic proteins (GFAP) and calretinin. Administration of GT with MSG counteracted the MSG-mediated oxidative stress by significantly increasing serum concentrations of GPX and NO and significantly decreasing concentrations of TAC. Furthermore, GT significantly increased levels of serum monoamines (dopamine, serotonin, and norepinephrine). Moreover, it ameliorated the histological changes, GFAP, and calretinin immunostaining in brain tissues. It is envisaged that GT will serve as a viable protective choice for the inclusion of the neurotoxicity treatment procedure.

Catechins and caffeine absorption, and antioxidant activity of tea-macerated wine in a Caco-2 intestinal cell culture model.

A novel style of flavored wine was developed via infusion of either black tea or green tea into Chardonnay wine. The bioaccessibility and bioavailability of phenolic substances in green/black tea-infused Chardonnay wine were investigated. Catechin, caffeine, and epicatechin gallate, originating from the tea, displayed high absorption rates with apparent permeability coefficient values above 10 × 10-6 cm/s in a human Caco-2 intestinal cell model. A paracellular pathway was proposed to drive the transport of catechin and epicatechin gallate, while the possible transport pathway of caffeine is passive transcellular diffusion route. Co-supplementation of flavonoids of quercetin or naringenin (20 µM) could further enhance the uptake of catechin and epicatechin gallate, but reduce the absorption of caffeine. Great in vitro and cellular antioxidant capacities were witnessed in the tea-macerated wine samples. The wine samples also neutralized the negative impact of tert-butyl hydroperoxide (25 µM) on glutathione S-transferase and glutathione levels, apoptosis induction, and intracellular malondialdehyde levels. RNA sequencing with limma method revealed a total of 1473 and 406 differentially expressed genes in the 21-day-old Caco-2 intestinal cells treated with the green and black tea-macerated wines for 5 h respectively, indicating metabolic changes in the cells from the different wines.

Zinc Treatment of Tea Plants Improves the Synthesis of Trihydroxylated Catechins via Regulation of the Zinc-Sensitive Protein CsHIPP3.

The tea plant (Camellia sinensis [L.] O. Kussntze) is a global economic crop. Zinc treatment of tea plants can enhance catechin biosynthesis. However, the underlying molecular mechanism behind catechin formation through zinc regulation remains unclear. This study identified a zinc-responsive protein, C. sinensis heavy metal-associated isoprenylated plant protein 3 (CsHIPP3), from zinc-treated tea seedlings. CsHIPP3 expression was positively correlated with trihydroxylated catechin (TRIC) content. CsF3'5'H1 is a crucial regulator of the TRIC synthesis pathway. The interaction between CsHIPP3 and CsF3'5'H1 was assessed using bimolecular fluorescence complementation, firefly luciferase complementation imaging, and pulldown experiments. CsHIPP3 knockdown using virus-induced gene silencing technology decreased the content of each component of TRICs. Compared with the control, the relative catechin content was reduced by 40.12-55.39%. Co-overexpression of CsHIPP3 and CsF3'5'H1 significantly elevated the TRIC content in tea leaves and calli. Moreover, the TRIC content in transient co-overexpression leaves was 1.44-fold higher than that of the control group, and tea callus was 50.83% higher in transient co-overexpression than in the wild type. Thus, zinc-regulated TRIC synthesis in a zinc-rich environment was mediated by binding CsHIPP3 with CsF3'5'H1 to promote TRIC synthesis and accumulation.