RESUMO
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.
Assuntos
Resíduos de Praguicidas , Praguicidas , Chá , Chá/química , Medição de Risco , Praguicidas/análise , Resíduos de Praguicidas/análise , Monitoramento Ambiental , Humanos , Fazendeiros , Agricultura , Camellia sinensis/química , Piretrinas/análise , China , Exposição Ocupacional/análiseRESUMO
The issue of soil acidification in tea plantations has become a critical concern due to its potential impact on tea quality and plant health. Understanding the factors contributing to soil acidification is essential for implementing effective soil management strategies in tea-growing regions. In this study, a field study was conducted to investigate the effects of tea plantations on soil acidification and the associated acid-base buffering capacity (pHBC). We assessed acidification, pHBC, nutrient concentrations, and cation contents in the top 0-20 cm layer of soil across forty tea gardens of varying stand ages (0-5, 5-10, 10-20, and 20-40 years old) in Anji County, Zhejiang Province, China. The results revealed evident soil acidification due to tea plantation activities, with the lowest soil pH observed in tea gardens aged 10-20 and 20-40 years. Higher levels of soil organic matter (SOM), total nitrogen (TN), Olsen phosphorus (Olsen-P), available iron (Fe), and exchangeable hydrogen (H+) were notably recorded in 10-20 and 20-40 years old tea garden soils, suggesting an increased risk of soil acidification with prolonged tea cultivation. Furthermore, prolonged tea cultivation correlated with increased pHBC, which amplified with tea stand ages. The investigation of the relationship between soil pHBC and various parameters highlighted significant influences from soil pH, SOM, cation exchange capacity, TN, available potassium, Olsen-P, exchangeable acids (including H+ and aluminum), available Fe, and available zinc. Consequently, these findings underscore a substantial risk of soil acidification in tea gardens within the monitored region, with SOM and TN content being key driving factors influencing pHBC.
Assuntos
Camellia sinensis , Monitoramento Ambiental , Nitrogênio , Solo , Solo/química , Camellia sinensis/química , Nitrogênio/análise , China , Concentração de Íons de Hidrogênio , Ecossistema , Fósforo/análise , Chá/química , AgriculturaRESUMO
BACKGROUND: The perennial evergreen tea (Camellia sinensis) plant is one of the most popular nonalcoholic drinks in the world. Fertilizers and industrial, agricultural, and municipal activities are the usual drivers of soil contamination, contaminating tea plants with potentially toxic elements (PTEs). These elements might potentially accumulate to larger amounts in the leaves of plants after being taken up from the soil. Thus, frequent monitoring of these elements is critically important. METHODS: The present study intended to determine PTEs (Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb) in both tea leaves and infusions using ICP-OES. Various multivariate data analysis methods such as principal component analysis (PCA) and hierarchical cluster analysis (HCA) were employed to elucidate the potential sources of PTEs contamination, whether from anthropogenic activities or natural origins. Additionally, Pearson's correlation coefficient (PCC) was calculated to assess the relationships between the variables under study. RESULTS: The mean contents (mg/L) of all studied elements in tea infusions decreased in order Mn (150.59⯱â¯1.66)â¯>â¯Fe (11.39⯱â¯0.99)â¯>â¯Zn (6.62⯱â¯0.89)â¯>â¯Cu (5.86⯱â¯0.62)â¯>â¯Co (3.25⯱â¯0.64)â¯>â¯Ni (1.69⯱â¯0.23)â¯>â¯Pb (1.08⯱â¯0.16)â¯>â¯Cr (0.57⯱â¯0.09)â¯>â¯Cd (0.46⯱â¯0.09)â¯>â¯Al (0.05⯱â¯0.008), indicating that Mn exhibits the highest abundance. The mean concentration trend in tea leaf samples mirrored that of infusions, albeit with higher concentrations of PTEs in the former. The tolerable dietary intake (TDI) value for Ni and provisional tolerable monthly intake (PTMI) value for Cd surpassed the standards set by the WHO and EFSA. Calculated hazard index (HIâ¯<â¯1) and cumulative cancer risk (CCR) values suggest negligible exposure risk. CONCLUSION: Elevated levels of PTEs in commonly consumed tea products concern the public and regulatory agencies.
Assuntos
Chá , Chá/química , Análise Multivariada , Análise de Componente Principal , Carcinógenos/análise , Oligoelementos/análise , Humanos , Folhas de Planta/química , Camellia sinensis/químicaRESUMO
Tea is the world's most common drink after water, and the world's annual sales exceed $43 billion, of which more than $11 billion is green tea (Camellia sinensis (L.)). Increasing evidence continues to show that green tea consumption and its ingredients have a variety of potential health benefits. The aim of the study was to control and assess the toxicological risk (TRA) of three heavy metals (As, Pb, and Cd) in infusions of green tea (n = 12) from Polish markets. We applied the method of inductive coupled plasma mass spectrometry (ICP-MS) to determine the selected heavy metal and designed a specific toxicological risk assessment with three crucial tiers. The first tier of our strategy was to determine the elements investigated (heavy metal impurities, µg/L). The second step was to estimate the weekly intake of green tea infusions (µg/week) based on weekly consumption. The third tier was to estimate the weekly intake per weight (µg/L/week/bw), based on the average weekly intake of green tea infusion per adult compared to the provisional weekly intake (PTWI) established by the FAO/WHO Joint Food Additives Expert Committee (JECFA). The levels of the investigated heavy metals occur at different levels in all of the investigated green tea infusions. The heavy metal profile indicated that As (0.0721-10.585 µg/L), Pb (0.386-1.695 µg/L), and Cd (0.126-0.346 µg/L) were present in all samples. Basic analysis of general content shows that As (average = 0.325 µg/L) was at a level similar to Cd (average = 0.214 µg/L). Surprisingly, the Pb content (average 0.891 µg/L) was approximately 2.75-4 times higher than that of As and Cd, respectively. The application of our proposed safety assessment methodology (three tiers) provides satisfactory results for regulatory purposes. The evaluation of the investigated heavy metals in all products analysed from green tea samples (infusions) showed that there were no health hazards to consumers due to weekly exposure. The results indicated that after drinking green tea infusions from Polish markets, the amount of investigated elements in weekly doses does not represent any health risks to consumers.
Assuntos
Camellia sinensis , Metais Pesados , Humanos , Adulto , Camellia sinensis/química , Chá/química , Cádmio/análise , Polônia , Chumbo/análise , Metais Pesados/análise , Medição de RiscoRESUMO
The metabolites of pesticides usually require rational risk assessment. In the present study, the metabolites of tolfenpyrad (TFP) in tea plants were identified using UPLC-QToF/MS analysis, and the transfer of TFP and its metabolites from tea bushes to consumption was studied for a comprehensive risk assessment. Four metabolites, PT-CA, PT-OH, OH-T-CA, and CA-T-CA, were identified, and PT-CA and PT-OH were detected along with dissipation of the parent TFP under field conditions. During processing, 3.11-50.00 % of TFP was further eliminated. Both PT-CA and PT-OH presented a downward trend (7.97-57.89 %) during green tea processing but an upward trend (34.48-124.17 %) during black tea manufacturing. The leaching rate (LR) of PT-CA (63.04-101.03 %) from dry tea to infusion was much higher than that of TFP (3.06-6.14 %). As PT-OH was no longer detected in tea infusions after 1 d of TFP application, TFP and PT-CA were taken into account in the comprehensive risk assessment. The risk quotient (RQ) assessment indicated a negligible health risk, but PT-CA posed a greater potential risk than TFP to tea consumers. Therefore, this study provides guidance for rational TFP application and suggests the sum of TFP and PT-CA residues as the maximum residual limit (MRL) in tea.
Assuntos
Camellia sinensis , Resíduos de Praguicidas , Praguicidas , Chá/química , Camellia sinensis/química , Praguicidas/análise , Medição de Risco , Contaminação de Alimentos/análise , Resíduos de Praguicidas/análiseRESUMO
The scientific interest in the medicinal properties of Kombucha beverages, a carbonated drink with live microorganisms, has increased recently. Hence, the aim of this study was to determine the chemical profile and to examine the antioxidant, antidiabetic and antineurodegenerative potential of unfermented and also Kombucha fermented Camellia sinensis (green tea), Coffea arabica (coffee), and Ganoderma lucidum (Reishi) extracts. The extracts were prepared as follows: the first (unfermented) set contained 1 L of water, 50 g of sucrose and 20 g of dried and ground green tea, coffee, or Reishi basidiocarp, while the second (fermented) set contained all of the aforementioned ingredients individually inoculated with Kombucha and fermented for 21 days. The chemical analysis was conducted using liquid chromatography-mass spectrometry (LC-MS). The antioxidant activity was assessed by DPPH, total reducing power (TRP), and ß-carotene bleaching assays. The inhibition of α-amylase and α-glucosidase activity was used to estimate the antidiabetic potential, while the level of inhibition of acetylcholinesterase (AChE) and tyrosinase (TYR) was used to evaluate the antineurodegenerative activity. The results suggested that the fermented extracts of green tea, coffee, and Reishi exert significant antioxidant effects, although they were lower compared to the unfermented extracts. The unfermented green tea extract exhibited the highest DPPH-scavenging activity (87.46%) and the highest preservation of ß-carotene (92.41%), while the fermented coffee extract showed the highest TRP (120.14 mg AAE per g) at 10 mg mL-1. Although the extracts did not inhibit the activity of α-amylase, they were quite effective at inhibiting α-glucosidase, especially the unfermented Reishi extract, inhibiting 95.16% (at a concentration of 10 mg mL-1) of α-glucosidase activity, which was slightly higher than the positive control at the same concentration. The most effective AChE inhibitor was unfermented green tea extract (68.51%), while the fermented coffee extract inhibited 34.66% of TYR activity at 10 mg mL-1. Altogether, these results are in accordance with the differences found in the extracts' chemical composition. Finally, this is the first report that highlights the differences in the chemical profile between the unfermented and Kombucha fermented green tea, coffee and Reishi extracts, while it also reveals, for the first time, the antineurodegenerative potential of Kombucha fermented Reishi extract. The examined extracts represent potent functional foods, while their more detailed mechanisms of action are expected to be revealed in future research.
Assuntos
Camellia sinensis , Coffea , Reishi , Antioxidantes/farmacologia , Antioxidantes/análise , Camellia sinensis/química , Hipoglicemiantes/farmacologia , Hipoglicemiantes/análise , alfa-Glucosidases , Acetilcolinesterase , beta Caroteno/análise , Cromatografia Gasosa-Espectrometria de Massas , Chá/química , alfa-Amilases , Extratos Vegetais/farmacologia , Extratos Vegetais/químicaRESUMO
BACKGROUND: Tea is one of the most popular drinks in the world. The growth of tea plant is inseparable from the control of pesticides on diseases and pests. Pyriproxyfen is used as a pesticide substitute to control insect pests in tea gardens, but little is known about its residue degradation. Here, we performed an integrative study of the degradation and metabolism of pyriproxyfen from the tea garden to the cup. RESULTS: The dissipation half-life of pyriproxyfen during tea growth was 2.74 days, and five metabolites PYPAC, PYPA, DPH-Pyr, 5''-OH-Pyr, and 4'-OH-Pyr were generated. The total processing factors for pyriproxyfen in green tea and black tea were 2.41-2.83 and 2.77-3.70, respectively. The residues of pyriproxyfen and its metabolites were affected by different processing steps. The total leaching rates of pyriproxyfen from green tea and black tea into their infusions were 9.8-12.3% and 5.3-13.8%, respectively. The leaching rates of the five metabolites were higher than that of pyriproxyfen and increased the intake risk. CONCLUSION: To ensure safe consumption, the recommended maximum residue limit value of pyriproxyfen in tea can be set to 5 mg kg-1 and the pre-harvest interval can be set to 5 days. © 2022 Society of Chemical Industry.
Assuntos
Camellia sinensis , Resíduos de Praguicidas , Camellia sinensis/química , Cromatografia Líquida , Resíduos de Praguicidas/análise , Piridinas , Medição de Risco , Espectrometria de Massas em Tandem , Chá/químicaRESUMO
BACKGROUND: Water-soluble fluoride (WS-F) can be absorbed directly by tea plants from soil and comprises a major source of dietary F in tea consumers. To reveal the WS-F accumulation in tea leaves and assess WS-F health risks, 70 sets of samples including tea leaves at three maturity stages and corresponding topsoil were collected from Xinyang, China. The WS-F contents in tea samples and pH values in soil samples were determined. RESULTS: The contents of WS-F in tea leaves exhibited a positive correlation with leaf maturity. The contents of WS-F in tea leaves showed a positive correlation with WS-F contents in the soil as the soil pH value exceeds 5. All the bud with two leaves samples, 84.29% of the third to sixth leaves samples, and 78.57% mature leaves samples in 5-min infusion tend to be no health threat. The leaching characteristics of WS-F from tea leaves were influenced by the leaf maturity and soaking time. CONCLUSION: Taking measures to control pH and WS-F concentration of plantations soil, as well as drinking tea infusion made from young leaves or reducing soaking time could decrease the WS-F health risk. © 2021 Society of Chemical Industry.
Assuntos
Camellia sinensis , Solo , Camellia sinensis/química , China , Fluoretos/análise , Folhas de Planta/química , Medição de Risco , Solo/química , Chá/química , Água/análiseRESUMO
The edible parts of the plants Camellia sinensis, Vitis vinifera and Withania somnifera were extensively used in ancient practices such as Ayurveda, owing to their potent biomedical significance. They are very rich in secondary metabolites such as polyphenols, which are very good antioxidants and exhibit anti-carcinogenic properties. This study aims to evaluate the anti-cancerous properties of these plant crude extracts on human liver cancer HepG2 cells. The leaves of Camellia sinensis, Withania somnifera and the seeds of Vitis vinifera were collected and methanolic extracts were prepared. Then, these extracts were subjected to DPPH, α- amylase assays to determine the antioxidant properties. A MTT assay was performed to investigate the viability of the extracts of HepG2 cells, and the mode of cell death was detected by Ao/EtBr staining and flow cytometry with PI Annexin- V FITC dual staining. Then, the protein expression of BAX and BCl2 was studied using fluorescent dye to determine the regulation of the BAX and BCl2 genes. We observed that all the three extracts showed the presence of bioactive compounds such as polyphenols or phytochemicals. The W. somnifera bioactive compounds were found to have the highest anti-proliferative activity on human liver cancer cells.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Camellia sinensis/química , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Vitis/química , Withania/química , Alcaloides/química , Alcaloides/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/antagonistas & inibidores , Compostos de Bifenilo/química , Morte Celular/efeitos dos fármacos , Flavonoides/química , Flavonoides/isolamento & purificação , Células Hep G2 , Humanos , Picratos/antagonistas & inibidores , Picratos/química , Extratos Vegetais/química , Folhas de Planta/química , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Sementes/química , Transdução de Sinais , Taninos/química , Taninos/isolamento & purificação , Terpenos/química , Terpenos/isolamento & purificação , alfa-Amilases/genética , alfa-Amilases/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismoRESUMO
BACKGROUND: Tolfenpyrad and dinotefuran are two representative pesticides used for pest control in tea gardens. Their application may bring about a potential risk to the health of consumers. Therefore, it is essential to investigate the residue behavior, transfer and risk assessment of tolfenpyrad, dinotefuran and metabolites from tea garden to teacup. RESULTS: An effective analytical method was established and validated to simultaneously determine tolfenpyrad, dinotefuran and its metabolites (DN and UF) in tea. The average recoveries of tolfenpyrad, dinotefuran, DN and UF were in the range 72.1-106.3%, with relative standard deviations lower than 11.8%. On the basis of the proposed method, the dissipation of tolfenpyrad and dinotefuran in fresh tea leaves followed first-order kinetics models with half-lives of 4.30-7.33 days and 4.65-5.50 days, respectively. With application amounts of 112.5-168.75 g a.i. ha-1 once or twice, the terminal residues of tolfenpyrad and total dinotefuran in green tea were lower than 19.6 and 7.13 mg kg-1 , respectively, and below their corresponding maximum residue limits . The leaching rates of tolfenpyrad and total dinotefuran during the tea brewing were in the ranges 1.4-2.3% and 93.7-98.1%, respectively. CONCLUSION: Tolfenpyrad and dinotefuran in tea were easily degraded. The RQc and RQa values for tolfenpyrad were 37.6% and 5.4%, which were much higher than for dinotefuran at 24.7% and 0.84%, respectively. The data indicated that there was no significant health risk in tea for consumers at the recommended dosages. The results provide scientific data regarding the reasonable use of tolfenpyrad and dinotefuran aiming to ensure safe tea consuption. © 2021 Society of Chemical Industry.
Assuntos
Camellia sinensis/crescimento & desenvolvimento , Guanidinas/química , Neonicotinoides/química , Nitrocompostos/química , Resíduos de Praguicidas/química , Pirazóis/química , Chá/química , Camellia sinensis/química , Camellia sinensis/metabolismo , Qualidade de Produtos para o Consumidor , Culinária , Contaminação de Alimentos/análise , Guanidinas/metabolismo , Humanos , Cinética , Neonicotinoides/metabolismo , Nitrocompostos/metabolismo , Resíduos de Praguicidas/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Pirazóis/metabolismo , Medição de Risco , Chá/metabolismoRESUMO
Tea is the one of the most popular non-alcoholic caffeinated beverages in the world. Tea is produced from the tea plant (Camellia sinensis (L.) O. Kuntze), which is known to accumulate fluoride. This article systematically analyzes the literature concerning fluoride absorption, transportation and fluoride tolerance mechanisms in tea plants. Fluoride bioavailability and exposure levels in tea infusions are also reviewed. The circulation of fluoride within the tea plantation ecosystems is in a positive equilibrium, with greater amounts of fluoride introduced to tea orchards than removed. Water extractable fluoride and magnesium chloride (MgCl2 ) extractable fluoride in plantation soil are the main sources of absorption by tea plant root via active trans-membrane transport and anion channels. Most fluoride is readily transported through the xylem as F- /F-Al complexes to leaf cell walls and vacuole. The findings indicate that tea plants employ cell wall accumulation, vacuole compartmentalization, and F-Al complexes to co-detoxify fluoride and aluminum, a possible tolerance mechanism through which tea tolerates higher levels of fluoride than most plants. Furthermore, dietary and endogenous factors influence fluoride bioavailability and should be considered when exposure levels of fluoride in commercially available dried tea leaves are interpreted. The relevant current challenges and future perspectives are also discussed. © 2020 Society of Chemical Industry.
Assuntos
Camellia sinensis/química , Fluoretos/análise , Fluoretos/metabolismo , Alumínio/análise , Alumínio/metabolismo , Disponibilidade Biológica , Transporte Biológico , Camellia sinensis/metabolismo , Parede Celular/química , Parede Celular/metabolismo , Exposição Dietética/efeitos adversos , Exposição Dietética/análise , Humanos , Folhas de Planta/química , Folhas de Planta/metabolismo , Medição de Risco , Solo/química , Chá/químicaRESUMO
Near-infrared (NIR) spectroscopy is an effective tool for analyzing components relevant to tea quality, especially catechins and caffeine. In this study, we predicted catechins and caffeine content in green and black tea, the main consumed tea types worldwide, by using a micro-NIR spectrometer connected to a smartphone. Local models were established separately for green and black tea samples, and these samples were combined to create global models. Different spectral preprocessing methods were combined with linear partial-least squares regression and nonlinear support vector machine regression (SVR) to obtain accurate models. Standard normal variate (SNV)-based SNV-SVR models exhibited accurate predictive performance for both catechins and caffeine. For the prediction of quality components of tea, the global models obtained results comparable to those of the local models. The optimal global models for catechins and caffeine were SNV-SVR and particle swarm optimization (PSO)-simplified SNV-PSO-SVR, which achieved the best predictive performance with correlation coefficients in prediction (Rp) of 0.98 and 0.93, root mean square errors in prediction of 9.83 and 2.71, and residual predictive deviations of 4.44 and 2.60, respectively. Therefore, the proposed low-price, compact, and portable micro-NIR spectrometer connected to smartphones is an effective tool for analyzing tea quality.
Assuntos
Cafeína/análise , Catequina/análise , Análise de Alimentos/instrumentação , Espectroscopia de Luz Próxima ao Infravermelho/instrumentação , Chá/química , Algoritmos , Cafeína/química , Calibragem , Camellia sinensis/química , Catequina/química , Quimioinformática/métodos , Análise de Alimentos/métodos , Qualidade dos Alimentos , Modelos Lineares , Modelos Químicos , Dinâmica não Linear , Smartphone , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Máquina de Vetores de SuporteRESUMO
Tea, a popular aromatic infusion and food supplement, prepared from Camellia sinensis (L.) Kuntze leaves, is often subjected to adulteration with various undeclared inorganic and plant-derived materials. Cashew (Anacardium occidentale L.) nut husk is one of the most common plant tea adulterants. To date, there are limited DNA-based technologies for tea authentication and quantitative detection of adulterants. Herein, we used a universal plant DNA barcoding marker coupled with High Resolution Melting (Bar-HRM) analysis to authenticate tea products from cashew ground nut. Additionally, cashew-specific markers coupled with HRM technology were used to detect and quantify adulteration of tea with cashew DNA. This methodology can reliably detect admixtures as low as 1% v/v cashew in commercial tea products. Overall, our results demonstrate that the HRM technology is a strong molecular approach in tea authentication, capable of detecting very low adulterations in DNA admixtures. PRACTICAL APPLICATION: In this study, we established the use of high-resolution DNA-based technologies for the detection of cashew adulteration in tea, even in very low quantities. The technology could be applied to a greater range of plant-based tea adulterants. This work is expected to facilitate the traceability and authenticity of tea products and form the basis for the development of strategies against fraudulent practices.
Assuntos
Anacardium/genética , Camellia sinensis/genética , Contaminação de Alimentos/análise , Chá/química , Anacardium/química , Camellia sinensis/química , Código de Barras de DNA Taxonômico/métodos , DNA de Plantas/química , DNA de Plantas/genética , Contaminação de Alimentos/economia , Marcadores Genéticos , Chá/economia , Temperatura de TransiçãoRESUMO
The total mean ∑[Formula: see text] in samples were from 75.3 to 387.0 ng/g dry weight (d.w) and showed high value in black dry tea, followed by herbal, oolong, and green tea. The mean ∑[Formula: see text] (a combination of benz[a]anthracene, chrysene, benzo[b]fluoranthene, and benzo[a]pyrene) values were 54.3 ng/g, 16.4 ng/g, 14.2 ng/g, and 6.6 ng/g for black, herbal, green, and oolong teas, respectively. Concentration for benzo[a]pyrene (BaP) was from 0.4 to 35.8 ng/g, and the BaP equivalent concentration values ranged from 0.3 to 48.1 ng/g. There was only 1 black tea sample that BaP concentration exceeded the maximum level according to European Union (EU) standards. Tea samples marketed in Vietnam showed insignificant difference with the samples from other origins by same analytical method. Black teas showed high PAHs contents in dry tea samples but the released percentage of sum of PAHs from tea-to-tea infusion was lower than that in other tea type samples. The released percentages of PAH4 from tea-to-tea infusion were 40.7, 15.4, and 1.9 for green, herbal, and black tea. High temperature in black tea manufacturing processes might reduce essential oil content in tea that might effect on the PAHs partially release into the infusion. Indeed, based on EU regulations, we may conclude that tea consumers are safe in risk of exposure to PAHs obtained from teas.
Assuntos
Exposição Dietética/análise , Contaminação de Alimentos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Chá/química , Benzo(a)pireno/análise , Camellia sinensis/química , Crisenos/análise , Exposição Dietética/efeitos adversos , Fluorenos/análise , Humanos , Folhas de Planta/química , Medição de Risco/métodos , Chás de Ervas/análise , VietnãRESUMO
Multiple pesticide residues are frequently present in tea leaves and while the majority of residues satisfy Taiwan's current health regulations, there are potential health effects from pesticide exposure that are of great concern for tea drinkers. We undertook a systematic probabilistic risk assessment of 59 pesticides in tea leaves from 1629 tea leaf samples obtained by Taiwan's Food and Drug Administration in two monitoring surveys in 2015. Bayesian statistics used a Markov Chain Monte Carlo approach to estimate posterior distributions of pesticide residues in tea leaves, lifetime average daily doses and hazard quotients (HQs) of evaluated pesticides. We classified 95th percentile values of HQs into three categories: 0 < HQ < 0.5, 0.5 ≤ HQ ≤ 1 and 1 < HQ. The 95th percentiles of HQs for triazophos (3.39), carbofuran (2.04) and endosulfan (1.80) exceeded 1 in the adult population; the HQ for 3-OH carbofuran was 0.97 and was less than 0.5 for the remaining 55 pesticides. The health risk posed by pesticide residues for tea drinkers is negligible, if triazophos, carbofuran, endosulfan, and 3-OH carbofuran residues satisfy regulatory standards. However, five legacy pesticides, DDT, methomyl, carbofuran, dicofol and endosulfan, were identified. To reduce uncertainties, this study combined Bayesian statistics with a mode of action approach for systematic risk assessment of co-exposure to multiple pesticide residues in tea leaf samples. Measuring pesticide transfer rates will improve the quality of future risk assessments concerning residues in tea leaves. Appropriate management of pesticides in Taiwanese tea farms and monitoring of pesticide residues in imported tea is warranted to protect Taiwan's tea drinkers.
Assuntos
Exposição Ambiental/análise , Resíduos de Praguicidas/análise , Praguicidas/análise , Folhas de Planta/química , Medição de Risco/métodos , Chá/química , Adulto , Teorema de Bayes , Camellia sinensis/química , Carbofurano/análise , Endossulfano/análise , Contaminação de Alimentos/análise , Humanos , TaiwanRESUMO
BACKGROUND: Methoxyfenozide possesses efficacy against a variety of lepidopteron pests, including the major pests in cauliflower and tea, so it is of great importance to generalize the practical use of methoxyfenozide in the field. RESULTS: An efficient method was developed and validated in both vegetable matrix and extract-rich matrix (cauliflower and tea) using modified QuEChERS combined with UPLC/MS/MS analysis. The recoveries in cauliflower, made tea and tea shoots ranged from 94.5 to 108.0%, from 85.0 to 91.6% and from 77.3 to 82.0% respectively, with relative standard deviations (RSDs) below 17.3% in all cases. The field results showed that methoxyfenozide dissipated in cauliflower with half-life (t1/2 ) at 2.5-3.5 days and in tea with t1/2 at 1.2 days. Combining the above experimental data and statistical food intake values, the risk quotient (RQ) values were significantly lower than 1. CONCLUSION: The quantification method of methoxyfenozide in cauliflower or tea has not been established until this study. The dissipation and dietary exposure risk assessment of methoxyfenozide in cauliflower and tea were investigated in the field. Methoxyfenozide dissipated rapidly in cauliflower despite different climates, and it dissipated faster in tea. The dietary risk of methoxyfenozide through cauliflower or tea was negligible to humans. This study not only provides guidance for the safe use of methoxyfenozide but also serves as a reference for the establishment of maximum residue limits (MRLs) in China. © 2019 Society of Chemical Industry.
Assuntos
Brassica/química , Camellia sinensis/química , Hidrazinas/análise , Hormônios Juvenis/análise , Resíduos de Praguicidas/análise , China , Cromatografia Líquida/métodos , Contaminação de Alimentos/análise , Meia-Vida , Humanos , Hidrazinas/química , Inseticidas/análise , Hormônios Juvenis/química , Brotos de Planta/química , Medição de Risco , Espectrometria de Massas em Tandem/métodos , Chá/químicaRESUMO
Cosmetic ingredients derived from Camellia sinensis (tea) plant parts function as antioxidants and skin conditioning agents-humectant and miscellaneous. The Cosmetic Ingredient Review (CIR) Expert Panel (Panel) reviewed relevant animal and human data related to these ingredients. The use of the leaf ingredients in beverages results in much larger systemic exposures than those possible from cosmetic use. Accordingly, concern over the systemic toxicity potential of leaf-derived ingredients is mitigated. Because product formulations may contain multiple botanical ingredients, each containing the same constituents of concern, formulators are advised to be aware of these constituents and to avoid reaching levels that may lead to sensitization or other toxic effects. The Panel concluded that the C sinensis leaf-derived ingredients are safe in the present practices of use and concentration described in this safety assessment when formulated to be nonsensitizing. However, the available data are insufficient to determine whether the non-leaf-derived ingredients are safe for use in cosmetics.
Assuntos
Camellia sinensis/química , Qualidade de Produtos para o Consumidor , Cosméticos/química , Extratos Vegetais/toxicidade , Animais , Humanos , Medição de RiscoRESUMO
Methylxanthines, purine alkaloids found in plants, are found in beverages (coffee, tea, cocoa) and foods (chocolate and other cocoa-containing foods) commonly consumed worldwide. Members of this family include caffeine, theophylline and theobromine. Methylxanthines have a variety of pharmacological effects, and caffeine and theophylline are used as pharmaceuticals. Methylxanthines are metabolized in the liver predominantly by the enzyme CYP1A2. Their co-administration with CYP1A2 inhibitors may lead to pharmacokinetic interactions. Little is known about the possible drug interactions between caffeine and substrates of other CYP450 enzymes. In our study, methylxanthine fractions inhibited CYP3A4 in a concentration-dependent manner. Concomitant consumption of green tea with CYP3A4 substrates could increase the possibility of interactions, and this requires further clarification. The inhibition of CYP3A4 is not only due to the presence of catechin derivatives but methylxanthines may also contribute to this effect.
Assuntos
Camellia sinensis/química , Inibidores do Citocromo P-450 CYP3A/química , Chá/química , Xantinas/química , Citocromo P-450 CYP3A/metabolismo , Inibidores do Citocromo P-450 CYP3A/farmacologia , Humanos , Xantinas/farmacologiaRESUMO
Tea is a natural resource of catechins and exhibits antioxidative and anticancer activities. This study was designed to elucidate the comparative efficacy of white tea and pure EGCG in containing benzo (a) pyrene (BaP)-induced pulmonary stress. Rats were treated with white tea extract (WT) (1%) and pure EGCG at a dose of 80µg/ml in drinking water on alternate days for 12 weeks (4 weeks prior, during and after BaP treatment). BaP(50â¯mg/kg b. wt) was administered to rats orally in olive oil twice a week for four weeks. The indices such as stress biomarkers (LPO, PCC & ROS), antioxidant enzymes (SOD, CAT, GSH, GST, GR, GPx) activities and lung histoarchitecture were assessed. BaP administration enhanced the levels of inflammatory markers (NO and citrulline) and reduced activities of antioxidant enzymes. We observed similar antioxidant efficacy by both WT and EGCG as seen by their ameliorative action in restoring BaP induced oxidative and inflammatory stress as well as lung histoarchitecture. Our findings suggest that WT is equally beneficial as EGCG in maintaining the integrity of alveoli and is a potential candidate to be used as a cost effective and protective agent in conditions of BaP-induced lung damage.
Assuntos
Benzo(a)pireno/toxicidade , Catequina/análogos & derivados , Sequestradores de Radicais Livres/uso terapêutico , Lesão Pulmonar/prevenção & controle , Extratos Vegetais/uso terapêutico , Chá/química , Animais , Biomarcadores/metabolismo , Camellia sinensis/química , Catequina/uso terapêutico , Citrulina/metabolismo , Feminino , Inflamação/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Carbonilação Proteica/efeitos dos fármacos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismoRESUMO
Tea and herbal infusions have been known for millennia for their health benefits. However for plants and active ingredients (of mineral and animal origin), it is necessary to consume very large quantities to achieve what is called the health claim dose, i.e., the dose for which the effect on health claim is established. Camellia sinensis leaves is traditionally used as plant infusion. This article aims to review the innovation afforded by the ABC (Bio Concentrate Assets®) patent. The ABC patent has developed an exclusive method of enriching organic tea leaves with organic herbal dry plant extracts using organic acacia gum. This method allows the coupling of concentrated dry extracts from medicinal plants on the Camellia sinensis leave extracts using acacia gum (arabic gum) and to reach to low enough health claim doses thanks to a higher concentration of active ingredients (tested until 10 ingredients). An example of ABC application is provided in a brief overview of manufacturing process for the "Gingo® tea" preparation. The main advantages of the ABC patent application are discussed. In conclusion, the ABC process offers a real breakthrough in the market of teas and herbal teas for health and wellness.