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A minireview of effects of white tea consumption on diseases

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... 25 There are several studies that highlight the effects of green and white teas and their bioactive compounds both in in vitro and in animal studies. 22,25,[45][46][47] The research carried out by Xia et al. showed a significant reduction in blood glucose and an improvement in glucose intolerance in mice after drinking white tea. In addition, a protective activity of the β-cells in the Langerhans islets against oxidative and inflammatory damage was observed. ...
... Although a poor hypoglycaemic effect was observed, it was able to reduce diabetic complications by inhibiting inflammatory factors and reducing ROS. 46 EGCG supplementation has also showed to improve glucose tolerance and to prevent the destruction of the Langerhans islets, modulate gene expression of relevant enzymes 25 and reducing serum glucose levels. 45 Tea flavonoids, on the other hand, can suppress the intestinal absorption of glucose by inhibiting the activity of -glucosidase and stimulating the glucose transporter 4 (GLUT4) by mediating glucose absorption and increasing insulin sensitivity. ...
... 45 Tea flavonoids, on the other hand, can suppress the intestinal absorption of glucose by inhibiting the activity of -glucosidase and stimulating the glucose transporter 4 (GLUT4) by mediating glucose absorption and increasing insulin sensitivity. 46 In addition, green tea quercetin and genistein inhibited the activity of the insulin receptor tyrosine kinase IRS-1, IRS-2. 22 Other in vitro studies in rats show that catechins and theaflavins help prevent hyperglycaemia by inhibiting β-cell damage and increasing insulin activity. ...
Article
Tea is one of the most consumed beverages around the world and as such, it is constantly the object of novel research. This review focuses on the research performed during the last five years to provide an updated view of the current position of tea regarding human health. According to most authors, tea health benefits can be traced back to its bioactive components, mostly phenolic compounds. Among them, catechins are the most abundant. Tea has an important antioxidant capacity and anti-inflammatory properties, which make this beverage (or its extracts) a potential aid in the fight against several chronic diseases. On the other hand, some studies report the possibility of toxic effects and it is advisable to reduce tea consumption, such as in the last trimester of pregnancy. Additionally, new technologies are increasing researchers' possibilities to study the effect of tea on human gut microbiota and even against SARS CoV-2. This beverage favours some beneficial gut microbes, which could have important repercussions due to the influence of gut microbiota on human health.
... However, no significant difference was observed between the average fluoride content in Tieguanyin tea from different production areas. A plausible explanation could be the different manufacturing procedure of the white tea in comparison to the Tieguanyin tea Sanlier et al., 2018). Tieguanyin tea was often processed from one bud and four or five leaves, while only one bud and three leaves were picked for white tea, and their tea plant varieties were different (Sanlier et al., 2018;Xu et al., 2018). ...
... A plausible explanation could be the different manufacturing procedure of the white tea in comparison to the Tieguanyin tea Sanlier et al., 2018). Tieguanyin tea was often processed from one bud and four or five leaves, while only one bud and three leaves were picked for white tea, and their tea plant varieties were different (Sanlier et al., 2018;Xu et al., 2018). Simultaneously, Tieguanyin tea is semi-fermented and white tea is not fermented. ...
... The significantly higher mean lead content for Tieguanyin tea than for that of white tea can be explained by the different types of leaves which are picked for them. With the different tea plant varieties, Tieguanyin tea was processed from one bud and four or five leaves, while white tea was processed from one bud and three leaves (Sanlier et al., 2018;Xu et al., 2018). Furthermore, older tea leaves tend to contain higher concentrations of lead than younger leaves (Natesan & Ranganathan. ...
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Food and beverage consumption is the most possible route of human exposure to undesirable elements. Tieguanyin tea and white tea are widely-consumed beverage, which may be contaminated by fluoride (F), lead (Pb), chromium (Cr), and cadmium (Cd). For this study, the contamination levels and dietary exposure risks of these elements were studied from 72 Tieguanyin tea samples and 40 white tea samples from Fujian Province, China. The average concentrations of these elements decreased in order from F, Pb, Cr to Cd in Tieguanyin tea, while white tea in order from F, Cr, Pb to Cd. Metal-to-metal correlation indicated a weak positive correlation between Pb/Cd pairs (Tieguanyin tea) and Pb/Cr pairs (white tea). A weak negative correlation pair was found for Cr/Cd in Tieguanyin tea. The hazard index levels were below one, suggesting that there was no significant non-carcinogenic health risk to tea drinking consumers under the current dietary intake. The total cancer risk values of Pb, Cd, and Cr via the consumption of Tieguanyin tea and white tea were 4.01×10-5 and 7.64×10-6, fell into the acceptable range of 10-6~10-4. It demonstrated that the cancer risk for consumers via drinking Tieguanyin tea and white tea was acceptable.
... It is made from tea leaves only by a prolonged withering process and a drying process [9,20]. White tea has protective effects against cardiovascular diseases, cancer, diabetes mellitus, obesity, central nervous system and microorganism-based diseases [21]. In addition, white tea has unique sweet and umami tastes as well as smoothly fresh and green odors [20]. ...
... The market and production of white tea is increasing in recent years due to the desirable flavor and excellent health benefits. Its production was 5140 tons in China in 2009, while rapidly reached 15,700 tons in 2014 [21]. The main volatile compounds in white tea were hexanal, linalool, 2-methyl-butanal, phenylethyl alcohol, benzaldehyde, benzene acetaldehyde, (Z)-3-hexen-1-ol, 1-hexanol, (E)-2-hexenal, geraniol, etc. [20]. ...
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The aroma of an instant white tea (IWT) was extracted through simultaneous distillation–extraction (SDE) and analyzed by sensory evaluation, gas chromatography-mass spectrometry-olfactometry (GC-MS-O), aroma reconstruction, omission test and synergistic interaction analysis. Sensory evaluation showed the IWT was dominated with floral and sweet notes. The SDE extract had the aroma similar to the IWT. The main volatile components in the SDE extract were benzyl alcohol, linalool, hotrienol, geraniol, α-terpineol, coumarin, camphene, benzeneacetaldehyde, 2-hexanone, cis-jasmin lactone and phenylethyl alcohol. GC-MS-O and aroma reconstruction experiments showed 16 aroma-active compounds. Linalool, trans-β-damascenone and camphene were the major contributors to floral, sweet and green notes based on flavor dilution analysis and omission test. Linalool and trans-β-damascenone had synergistic effect to promote floral and sweet notes. Camphene and trans-β-damascenone had synergistic effect to reduce green and sweet notes. The study helps to understand the aroma of IWT and antagonism interactions among aroma-active volatiles.
... White tea (WT) differs from other tea types by being produced from young shoots and leaves of the plant, which undergoes minimal processing (Alcazar et al., 2007). Several biologic properties of WT, such as antioxidant, anti-inflammatory, anti-viral, anti-carcinogenic, and DNA protection, are attributed to its high content of polyphenols, especially catechins (Hajiaghaalipour et al., 2015;Pastoriza et al., 2017;Sanlier et al., 2018), besides gallic acid is also present in large amounts (Damiani et al., 2014;Lin et al., 2017). ...
... The most abundant phenolic compounds present in WT were gallic acid, quercetin, and catechin, according to UPLC-MS/MS analyses. Catechins have been identified as the major class of polyphenols in WT in many studies, whose antioxidant effects are attributed (Damiani et al., 2014;Tan et al., 2017;Sanlier et al., 2018). The (− )-epigallocatechin and (− )-epigallocatechin gallate were the catechins found in higher concentrations in WT by Tan et al. (2017) and Damiani et al. (2014). ...
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The interest in nutritional strategies that may counteract the deleterious oxidative effects induced by strenuous exercises is remarkable. Herein, the impact of white tea (Camellia sinensis) (WT), a polyphenol-rich beverage, on antioxidant status in endurance-trained rats after one session of exhaustive exercise were evaluated. Male Wistar rats were divided into groups, which received: control groups - water, and testing groups - WT1 (0.25%; w/v) or WT2 (0.5%; w/v). Drinks were consumed, ad libitum, for 5 or 10 weeks, concomitantly with the running training. Exhaustive running tests were applied before and after the experimental periods. WT intake increased the serum antioxidant capacity of rats in a dose-dependent manner (P < 0.001), which was unaccompanied by the activity of endogenous antioxidant enzymes SOD, GPx, and GR, and GSH content. Inflammatory markers in serum [IL-1β (P = 0.004) and IL-6 (P = 0.001)] could be downregulated by tea intake. In liver tissue, lower levels of lipid oxidation (P < 0.05) and improved antioxidant defenses (SOD, GPx, GR, and GSH, P < 0.05) were related to the consumption of WT in both doses, supporting protective effects in this responsible metabolic organ. In conclusion, long-term consumption of WT could be a promising adjuvant to exercise-stress management, emphasizing its ability to regulate antioxidant responses and prevent oxidative tissue damage.
... Based on the literature review, the infusions of white, green, and black teas have many benefits including antioxidant and anticancer effects (4)(5)(6)(7). However, all kinds of teas (black, green, oolong, and white tea) possess anti-oxidative, anti-inflammatory, anti-mutagenic, anti-carcinogenic, anti-microbial, anti-viral, anti-fungal effects, and offering resistance to obesity and cardiovascular complications (3,(8)(9)(10)(11)(12). ...
... Based on the literature, when the catechin and epigallocatechin gallate contents of white and green tea were compared, it was higher in green tea (12,(24)(25)(26). Furthermore, these results that showed higher catechin proportions found in white tea could explain its high biological activities (anti-oxidant, anti-inflammatory, anti-cancer, anti-diabetic, anti-microbial, and reduced cardiovascular diseases) in comparison to green and black teas (11,(27)(28). In conclusion, the literature reviews have shown that there are no detailed scientific studies on white, green, and black tea grown in Turkey and white tea has been considered as requiring clinical trials. ...
... White tea, one of six kinds of teas in China, originates from, and is mainly produced in, the northeast of Fujian province, and has received increasing attention in China owing to its charming flavors and significant health benefits [1]. Based on the tenderness level of fresh tea leaves, white teas are generally 22 aromatic hydrocarbons, 27 alcohols, 45 aldehydes, 39 ketones, 29 esters, 3 acids, 15 oxygen heterocyclic compounds, 10 nitrogen compounds, 1 sulfur compound, and 2 other compounds (Supplementary Table S2). ...
... cis-3-hexenyl butyrate (2.3), with an herbal and fresh scent, was only detected in SM. Note: [1] The presented aroma intensity of each compound was the average value obtained from the effective assessors; [2] STD means the compound was identified by authentic standards; [3] the classification of odor characteristics of each compound, Class A: herbal-like scents; Class B: pleasant (floral, fruity, sweet) scents; Class C: baked scents; Class D: unpleasant scents. ...
Article
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The identification of aroma composition and key odorants contributing to aroma characteristics of white tea is urgently needed, owing to white tea’s charming flavors and significant health benefits. In this study, a total of 238 volatile components were identified in the three subtypes of white teas using headspace solid-phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (GC × GC–TOFMS). The multivariate statistical analysis demonstrated that the contents of 103 volatile compounds showed extremely significant differences, of which 44 compounds presented higher contents in Baihaoyinzhen and Baimudan, while the other 59 compounds exhibited higher contents in Shoumei. The sensory evaluation experiment carried out by gas chromatography–olfactometry/mass spectrometry (GC–O/MS) revealed 44 aroma-active compounds, of which 25 compounds were identified, including 9 alcohols, 6 aldehydes, 5 ketones, and 5 other compounds. These odorants mostly presented green, fresh, floral, fruity, or sweet odors. Multivariate analyses of chemical characterization and sensory evaluation results showed that high proportions of alcohols and aldehydes form the basis of green and fresh aroma characteristic of white teas, and phenylethyl alcohol, γ-Nonalactone, trans-β-ionone, trans-linalool oxide (furanoid), α-ionone, and cis-3-hexenyl butyrate were considered as the key odorants accounting for the different aroma characteristics of the three subtypes of white tea. The results will contribute to in-depth understand chemical and sensory markers associated with different subtypes of white tea, and provide a solid foundation for tea aroma quality control and improvement.
... The synthesis of nanoparticles (NPs) of silver nitrate (AgNO 3 ) may become the desired convenient drug as chemopreventive agent is taken orally that directly reaches specific target cancer site [4]. White tea, which the hydrophilic extracts were used for synthesizing nanoparticles (WTNPs), contain high antioxidant which may attribute to anti-cancer effect [5]. On top of that, this was the first innovated investigation of WTNPs in vivo. ...
... EGCG is further classified under the epicatechin group which is found abundant in WT. It has previously seen to suppress cancer formation including CRC, on top of other benefits such as inverse association with kidney stones, neurodegenerative disease and diabetes mellitus [5]. However, the bioavailability of EGCG was reported low in solubility in gastrointestinal fluid, low absorption ability, easily metabolized and eliminated before directly targeting affected site and unspecific distribution [7]. ...
Article
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White tea (WT) has the highest amount of catechin which previously was found to enhance anti-cancer activity. To enhance the bioavailability of WT, silver nanoparticle (AgNP) was used to synthesize WT nanoparticle (WTNP). This present study aimed to determine the effectiveness of WTNP alone and co-administered with 5FU in the prophylactic study. WTNP was characterized by UV–Vis spectra, X-ray diffraction (XRD) spectra, transmission electron microscope (TEM) and Fourier-transform infrared spectroscopy (FTIR) and tested for their acute toxicity. In animal studies, all groups except the naïve group were given once a week 65 mg/kg of 1,2-dimethylhydrazine (DMH) subcutaneously, intraperitoneal injection of 50 mg/kg 5FU and daily administration of DMH 50 mg/kg WT and 5FU WTNPs. Aberrant crypt foci (ACF) and histology were determined and analysed. WTNP showed circular and pseudospherical shaped and 25–50 nm size range with no acute toxicity observed on rats. The DMH group was the highest in average ACF count (37.3 ± 3.18), which ACF was shown to decrease using the treatment, WT group (16.67 ± 3.28), 5FU monotherapy (5.67 ± 2.19) and WTFU (6.33 ± 1.33). The highest AC frequency was found at the DMH group (24.67 ± 1.20, 12.67 ± 1.45) compared to other groups. The chemo-suppressive effect of WTNP and WTFU combined effects was observed in the present study. WTNP expresses anti-cancer properties; however, it does not produce any synergistic effect.
... is plant is a species belonging to the eaceae family and has small perennial shrubs, widely used to produce teas, especially green and black [9]. ese teas have several pharmacological properties, with their production being carried out mainly in regions of tropical and subtropical climate, with abundant and regular rainfall [9,10]. According to its fermentation and maturation process, C. sinensis tea can be classified as green, white, yellow, red, and black, where important differences can be verified according to its cultivation and leaf processing [6,11]. ...
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Purpose. This study aimed to evaluate reports of patents for oral care formulations, based on Camellia sinensis (C. sinensis), deposited and granted in intellectual property banks. Methods. A survey was conducted through collection, treatment, and analysis of extracted information from patent reports selected. The documentary research was conducted in January 2021 on formulations with C. sinensis for dental applications, including since the first patent deposits until the current time. The risk of bias of clinical trials with these formulations was analyzed to verify the scientific evidence. The data extracted represent the distribution of the number of patents by banks, annual evolution of patent deposits, applicant of patents by country, distribution of patents according to International Patent Classification codes, and the types of patented products. Results. Data and information from 20 selected patents were extracted. The United States Patent and Trademark Office (USPTO) and World Intellectual Property Organization (WIPO) were the banks with the largest number of patents for products/formulations with C. sinensis for oral care applications with 7 (35%) and 6 (30%) patent registrations, respectively. Other banks did not provide patents related to the search. Patents of compositions were the largest with 14 filings, and the remainder of formulations are represented specially by mouthwashes and toothpastes. As for clinical application, 18 patents were filed as products with antimicrobial and antibiofilm action, while 2 patents are directed to the treatment of xerostomia. In general, the aspects of the studies of clinical efficacy pointed to a low risk of bias. Conclusion. The study pointed out a small number of products protected by patents for Camellia sinensis for oral care indication, highlighting mainly mouthwash compositions and formulations. In the methodological parameters of clinical trials carried out with the formulations, the majority pointed out a low risk of bias. 1. Introduction The practice of using medicinal plants with pharmacological activities for the treatment of diseases is ancient, including for conditions related to oral health. The use of natural products as medicinal therapy existed long before the pharmaceutical industry and after the emergence of these products has been incorporated into the development of formulations to the present day [1–3]. Herbs and medicinal plants can be used in different ways, including whole herb, leaves, roots, essential oils, and prepared as teas, syrups, creams, ointments, and even capsules or pills that contain a powdered form of the plant [4]. Tea constitutes an infusion prepared from dry leaves and is the second most consumed drink in the world, its consumption being surpassed only by water, in addition to having great cultural and economic relevance in several countries. Among the most varied types of teas, Camellia sinensis (C. sinensis) teas stand out as one of the most popular and used worldwide [5–7]. C. sinensis is a plant rich in polysaccharides, caffeine, polyphenols, amino acids, and antioxidants, in addition to micro and macronutrients beneficial to human health [8]. It has different important pharmacological properties such as antimicrobial, antioxidant, antidiabetic, and anti-inflammatory activities, in addition to its consumption presenting several documented benefits related to oral health, especially regarding caries and periodontal diseases [3, 6]. This plant is a species belonging to the Theaceae family and has small perennial shrubs, widely used to produce teas, especially green and black [9]. These teas have several pharmacological properties, with their production being carried out mainly in regions of tropical and subtropical climate, with abundant and regular rainfall [9, 10]. According to its fermentation and maturation process, C. sinensis tea can be classified as green, white, yellow, red, and black, where important differences can be verified according to its cultivation and leaf processing [6, 11]. Green tea from C. sinensis has a strong antioxidant power through its polyphenolic chemical constituents, beneficial in several clinical conditions such as dental caries, gingivitis, periodontitis, and halitosis, in addition to neuroprotection in the oral cavity [1]. Since it has a high concentration of fluoride in its nutrient composition, the consumption of this tea is extremely beneficial in repairing dental tissue in an acidic environment and improving resistance to demineralization [12, 13]. Furthermore, it has been shown that this tea has other properties, such as antiviral action against influenza viruses, herpes viruses, and antifungal action against Candida albicans, Trichophyton mentagrophytes, and Trichophyton rubrum [14]. Black tea is a product of C. sinensis treated with an oxidation process that requires longer steps and contains a greater amount of caffeine when compared to other teas from this plant. Its continued use can reduce blood pressure, the risks of type 2 diabetes, and improve the lipid profile. Its polyphenolic constituents promote health benefits, mainly in obesity, diabetes, cancer, atherosclerosis, inflammatory diseases, and osteoporosis [15–18]. In recent years, the search for new substances and formulations with pharmacological potential and biocompatibility has increased, which is revealed by the growing number of studies on the use of natural products. Often these studies seek to generate new technologies for society with a natural raw material traditionally used, giving rise to the development of innovations and patents [19, 20]. The elaboration of an invention patent or utility model is an extremely relevant indicator to mainly evaluate the level of development and technological innovation in industries and research institutions. Therefore, natural products are sources of biomolecules or therapeutic complexes that can be used for technological innovation and maintain competition in the market in several areas, including products for dental applications [21, 22]. Given the economic importance and medicinal products of C. sinensis, as well as its several benefits to systemic and mainly oral health, this study aimed to evaluate reports of patents deposited and granted on dental formulations based on C. sinensis in intellectual property banks. 2. Materials and Methods 2.1. Elaboration of the Technological Prospective Study The survey was conducted through collection and analysis of extracted information from patent reports selected. The documentary research was conducted in January 2021 about formulations with C. sinensis for dental applications, including since the first patent deposit in 2004 until all the year of 2020. The searches were direct with access to reports of patents deposited and granted in the following intellectual property banks of worldwide references:(1)Canadian Intellectual Property Office (CIPO)—Canada(2)China National Intellectual Property Administration (CNIPA)—China(3)Espacenet—European Patent Office (EPO)—Europe(4)German Patent and Trademark Office (DPMA)—Germany(5)Intellectual Property India—India(6)Japanese Patent Office (JPO)—Japan(7)National Institute of Intellectual Property (INPI)—Brazil(8)Swiss Federal Institute of Patent Office (IGE-IPI)—Switzerland(9)United States Patent and Trademark Office (USPTO)—United States(10)World Intellectual Property Organization (WIPO)—Europe 2.2. Search Strategy and Data Extraction For the preparation of the study, we conducted a mapping of patent applications using the keyword “Camellia sinensis” in the search field. All patent documents that included this term were initially considered in the search with the exploratory reading of titles and summaries, as a criterion for inclusion of the patents found. Then, only the active reports related to dentistry were selected; expired, abandoned, or denied patents were not included. Relevant information that describes the invention in the patent reports was selected and organized in graphics in GraphPad Prism 6 program to analyze descriptive statistics. The data extracted represent the distribution of the number of patents by banks, annual evolution of patent deposits, applicant of patents by country, distribution of patents according to International Patent Classification (IPC) codes, and the types of patented products. 2.3. Scientific Evidence According to the patents selected at the end of the search, the described inventions and their purposes with dental applications were evaluated and were searched clinical trials related to each selected patent in PubMed. 2.4. Risk of Bias Assessment Trials were assessed using Cochrane’s tool for assessing the risk of bias in randomized trials [23]. The tool includes the following domains: random sequence generation, allocation concealment, blinding of participants and personnel, blinding of outcome assessment, incomplete outcome data, selective reporting, and other sources of bias. We rated each domain as low risk, unclear risk, or high risk of bias. We classified the overall risk of bias as low if all domains were at low risk of bias, as high if at least one domain was at high risk of bias, or as unclear if at least one domain was at unclear risk of bias, and no domain was at high risk. This rule is specified by the Cochrane tool for assessing the risk of bias in randomized controlled trials because any source of bias in a trial is problematic, and there is a paucity of empirical research to prioritize one domain over the other. 3. Results The initial search resulted in 5126 patents found with the term “Camellia sinensis” in the intellectual property banks selected, followed by the stage title and abstract read targeting dental applications from the first patent deposited until the last one that had a total of 28 patent registrations. Then, the repeated records (8) were deleted. At the end of the search, data and information from 20 selected patents were extracted (Table 1). Title Publication number Product Country Year Classification IPC Inventor 1 Oral care composition containing extract of unoxidized Camellia 4852/DELNP/2007 Composition US 2005 A61K Colgate–Palmolive® 2 Oral compositions containing oxidized Camellia 4860/DELNP/2007 Composition US 2005 A61K/A61Q Colgate–Palmolive® 3 Oral composition comprising Camellia extract of semioxidized tissue from a member of the genus Camellia and an enhancing agent 2387/KOLNP/2009 Composition UK 2006 A01N Kingston University 4 Composição de higiene oral, método de tratamento ou prevenção de xerostomia e uso de polifenol de chá verde (gtp) (in Portuguese) BRPI1008380 Composition US 2008 A01N/A61K Georgia Health Sciences University Research Institute, Inc. 5 Composição oral, e, métodos para a promoção da saúde oral de um paciente animal, e para a redução da extensão de descoloração em uma pasta de dentes (in Portuguese) BRPI0519427 (A2) Toothpaste US 2004 A61K/A61Q Colgate–Palmolive® 6 Formulação tópica de uso bucal e seu uso (in Portuguese) BR102016237505 Composition BR 2016 A61K/A61P University of São Paulo 7 Composições odontológicas contendo inibidores de metaloproteinases e seus usos (in Portuguese) PI 1003771-3 Composition BR 2010 A61K/A61Q University of São Paulo 8 Oral care composition WO2017/199453 Toothpaste IN 2012 A61K/A61Q Nippon Zettoc Co., Ltd. 9 Oral care compositions for treating xerostomia PCT/US2010/024906 Composition US 2009 A01N/A61K University of São Paulo 10 Compositions for the treatment and prevention of infections of the oral cavity PCT/EP2009/002515 Composition IT 2009 A61K/A61P Indena SpA Company 11 Noncarious material and anticarious agent containing rare sugar US 20100166678 A1 Composition JP 2006 A61K/A61P Matsutani Chemical Industry Co., Ltd./National University Corporation Kagawa University 12 Antibacterial oral rinse formulation for preventing coronary artery disease US 20070154414 A1 Mouthwash US 2005 A61K Richard Paul Bonfiglio 13 Epigallocatechin-3-gallate crystal compositions WO2008/153938 Composition US 2007 C09K/A61P/C07D/A61K University of South Florida 14 Oral care compositions containing combinations of antibacterial and host-response modulating agents US 20070053849 A1 Composition US 2006 A61K/A61P/A61Q The Procter & Gamble Company 15 Use of a phenol-containing extract from Camellia sinensisin oral and dental cleaning agents for improving the visual appearance of the gums WO/2016/062449 Composition DE 2016 A61K/A61Q Henkel Ag & Co., KGaA 16 Oral composition containing saponin extracted from the root of Camellia sinensis for effectively preventing or treating periodontal diseases KR1020130035323 Composition KR 2013 A61K/A61Q/Y10S Jeong Kee Kim; Su Kyung Kim; Dae Bang Seo; Seok Sik Moon 17 Composition for enhancing oral hygiene comprising natural extract as active ingredient and use thereof KR1020160050108 Composition KR 2016 A61K/A61P/A61Q Dongguk University Gyeongju Campus Industry-Academy Cooperation Foundation 18 Effervescent mouthwash US20130149359 Mouthwash KR 2011 A61K/A61Q Eric M. Sanders 19 Health care buccal bag for refreshing mouth smell CN101015516 Bagged tea CN 2007 A61K/A61Q/A61P/A23F Zhu Huagang 20 Foamable mouthwash solid formulation and preparation method therefor WO/2020/054996 Mouthwash KR 2020 A61K Eun Sang Lee
... According to the complex production processes, tea can be classified into six categories, including white, green, yellow, oolong, black, and dark teas. White and green teas are not fermented, yellow tea is just slightly fermented, while oolong, black, and dark teas are more deeply fermented [2][3][4][5][6][7]. Tea contains various bioactive components, such as polyphenols, pigments, polysaccharides, alkaloids, free amino acids, and saponins [8][9][10][11][12][13]. ...
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Tea is widely consumed all over the world. Generally, tea is divided into six categories: White, green, yellow, oolong, black, and dark teas, based on the fermentation degree. Tea contains abundant phytochemicals, such as polyphenols, pigments, polysaccharides, alkaloids, free amino acids, and saponins. However, the bioavailability of tea phytochemicals is relatively low. Thus, some novel technologies like nanotechnology have been developed to improve the bioavailability of tea bioactive components and consequently enhance the bioactivity. So far, many studies have demonstrated that tea shows various health functions, such as antioxidant, anti-inflammatory, immuno-regulatory, anticancer, cardiovascular-protective, anti-diabetic, anti-obesity, and hepato-protective effects. Moreover, it is also considered that drinking tea is safe to humans, since reports about the severe adverse effects of tea consumption are rare. In order to provide a better understanding of tea and its health potential, this review summarizes and discusses recent literature on the bioactive components, bioavailability, health functions, and safety issues of tea, with special attention paid to the related molecular mechanisms of tea health functions.
... EGCG is the most abundant and active compound in green tea (Mir, Rasool, Rehman, Amin, & Ali, 2019). EGCG consumption has been associated with prevention of cardiovascular diseases, cancers and neurodegenerative disease (Sanlier, Atik, & Atik, 2018). Modulation of epigenetic processes such as DNA methylation is linked to this green tea catechin anticancer effects (Table 1). ...
Article
Consumption of bioactive compounds such as polyphenols, isothiocyanates, sulfur-containing compounds and terpenoids, found in fruits and vegetables, is associated with prevention of chronic disease. These bioactive food compounds elicit their protective effects through complex mechanisms at the cellular and molecular, including epigenetic levels. According to the Developmental Origins of Health and Disease (DOHaD) paradigm, in utero exposure to stressors such as malnutrition through maternal diet would impair fetal development and epigenetically program increased risk of metabolic diseases and some cancers in adult life. In addition, a role for fathers´ diet during preconception on their offspring health and chronic disease susceptibility has also emerged. This highlights early life as a promising window of opportunity for starting dietary interventions focusing on preventing chronic diseases. However, knowledge on the potential beneficial impact of early life exposure to bioactive food compounds is limited. Among the studies that have investigated bioactive food compounds in the context of DOHaD, most have focused on the impact of dietary polyphenols. Thus, in this review we discuss experimental evidence supporting a role for the dietary polyphenols resveratrol, genistein, epigallocatechin-3-gallate and anthocyanins in chronic disease prevention considering a perspective from early-life interventions through maternal and paternal diets and focusing on epigenetics as a potential underlying mechanism.
... Gallic acid, containing multiple hydroxyl groups, inhibits lipid peroxidase, and it breaks free radical chains by providing multiple protons 18) . Gallic acid has been shown in experiments to have anti-hyperlipidemic, cardioprotective, and anti-diabetic effects 25,27) . Additionally, gallic acid can exert neuroprotective effects as a result of its mono-and poly-targeted behavior 31,33) . ...
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Objective: Peripheral nerve injuries occur mostly as a result of mechanical trauma. Due to the microvascular deterioration in peripheral nerve damage, it becomes challenging to remove free oxygen radicals. Gallic acid is a powerful antioxidant with anti-inflammatory effects and a free radical scavenger. The purpose of the study is to show that gallic acid contributes to the restorative effect in mechanical nerve damage, considering its antioxidant and anti-inflammatory effects. Methods: Thirty male Sprague Dawley albino mature rats were included in the study. Ten of them constituted the control group, 10 out of 20 rats for which sciatic nerve damage was caused, constituted the saline group, and 10 formed the gallic acid group. Post-treatment motor functions, histological, immunohistochemical, and biochemical parameters of the rats were evaluated. Results: Compared to the surgery+saline group, lower compound muscle action potential (CMAP) latency, higher CMAP amplitude, and higher inclined plane test values were found in the surgery+gallic acid group. Similarly, a higher nerve growth factor (NGF) percentage, a higher number of axons, and a lower percentage of fibrosis scores were observed in the surgery+gallic acid group. Finally, lower tissue malondialdehyde (MDA) and higher heat shock protein-70 (HSP-70) values were determined in the surgery+gallic acid group. Conclusion: Gallic acid positively affects peripheral nerve injury healing due to its anti-inflammatory and antioxidant effects. It has been thought that gallic acid can be used as a supportive treatment in peripheral nerve damage.
... Immediately after collection, the white tea is evaporated and dried to prevent oxidation. It has a light and delicate taste (Sanlier et al., 2018). To produce green tea, young leaves are rolled and steamed to minimize oxidation. ...
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The effects of powder and infusions of white, black and green teas on the physicohemical and sensory characteristics of minced beef during refrigerated storage for 7 days. Seven groups were prepared: control (C), powder and infusion forms of black (BTP and BTI), green (GTP and GTI) and white (WTP and WTI) teas. Lipid oxidation (TBARS), antioxidant activity (DPPH), pH and color analyses were conducted on the 1st, 3rd, 5th and 7th days. The pH values of the samples increased with the progress of the storage and were found to be in the range of 5.44‐5.86 throughout the storage. Different tea treatments significantly (P<0.05) decreased the TBARS numbers of samples compared to control group. At the end of the storage, the lowest TBARS was found in the groups of GTI and WTI as 0.10 mg MA/kg sample. The highest DPPH values were found in WTP (50.50‐57.45%) during 7 days of storage.
... It was prepared by applying the only discoloration and drying processes without fermenting the young leaves and buds of Camellia sinensis. Epigallocatechin gallates have been indicated as major polyphenols in white tea as such in green tea 36 . Although it was shown by glycerol measurement that white tea extract induced the increase of lipolysis activity in differentiated adipocytes, it was inadequate to explain the decrease in triglycerides. ...
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The replacement of consumed with foods containing high carbohydrates, fats and proteins exceed that the daily needs of body, causes many health problems, especially obesity. Complicated health problems have been trying to be solved with drugs, but it is not possible to control diseases if obesity is not resolved. Obesity causes inflammation, insulin resistance, vascular endoth elial dysfunction, and Low-Density Lipoprotein (LDL) increase. There are very few weight loss drugs with acceptable side effects, and these drugs are not given to people who are not considered obese according to their body mass index. For this reason, people seek the remedy in over the counter (OTC) (mostly products with active ingredients derived from plants) products or herbal teas. These products, which do not have direct effects, have mechanisms that can help and can be supportive with diet and sports. However, these products and teas that cannot be dosed by a knowledgeable healthcare professional can disrupt the balance of the body and cause various diseases. In this study, the effect levels with the mechanisms supporting weight loss on the biochemical parame ters of the active substances in the herbal forms sold and consumed as diet tea, were evaluated.
... Its taste contributes to the fresh taste of green tea infusion. It has also many biological activities, such as relaxation, antihypertension, and hepatic protective effects (Sanlier, Atik, & Atik, 2018;Sanlier, Gokcen, & Altug, 2018). In addition, theanine participates in the development of tea aroma by the Maillard reaction, thus producing the caramel and roasted flavor. ...
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Tea is a typical processed beverage from the fresh leaves of Camellia sinensis [Camellia sinensis (L.) O. Kuntze] or Camellia assamica [Camellia sinensis var. assamica (Mast.) Kitamura] through different manufacturing techniques. The secondary metabolites of fresh tea leaves are mainly flavan-3-ols, phenolic acids, purine alkaloids, condensed tannins, hydrolysable tannins, saponins, flavonols, and their glycoside forms. During the processing, tea leaves go through several steps, such as withering, rolling, fermentation, postfermentation, and roasting (drying) to produce different types of tea. After processing, theaflavins, thearubigins, and flavan-3-ols derivatives emerge as the newly formed compounds with a corresponding decrease in concentrations of catechins. Each type of tea has its own critical process and presents unique chemical composition and flavor. The components among different teas also cause significant changes in their biological activities both in vitro and in vivo. In the present review, the progress of tea chemistry and the effects of individual unit operation on components were comprehensively described. The health benefits of tea were also reviewed based on the human epidemiological and clinical studies. Although there have been multiple studies about the tea chemistry and biological activities, most of existing results are related to tea polyphenols, especially (-)-epigallocatechin gallate. Other compounds, including the novel compounds, as well as isomers of amino acids and catechins, have not been explored in depth.
... Tea has antibacterial activity due to the abundant polyphenols (Sanlier, Atik, and Atik 2018). The extract of FBT showed significant inhibition of Shigella sonnei and Staphylococcus aureus with more than 50% growth inhibition at a concentration of 5 mg/mL or less (Keller et al. 2013). ...
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Fuzhuan brick tea (FBT) is a traditional popular beverage in the border regions of China. Nowadays, FBT has been attracted great attention due to its uniquely flavor and various health-promoting functions. An increasing number of efforts have been devoted to the studies on health benefits and chemistry of FBT over the last decades. However, FBT was still received much less attention than green tea, oolong tea and black tea. Therefore, it is necessary to review the current encouraging findings about processing, microorganisms, chemical constituents, health benefits and potential risk of FBT. The fungus fermentation is the key stage for processing of FBT, which is involved in a complex and unique microbial fermentation process. The fungal community in FBT is mainly dominated by “golden flower” fungi, which is identified as Aspergillus cristatus. A great diversity of novel compounds is formed and identified after a series of biochemical reactions during the fermentation process of FBT. FBT shows various biological activities, such as antioxidant, anti-inflammatory, anti-obesity, anti-bacterial, and anti-tumor activities. Furthermore, the potential risk of FBT was also discussed. It is expected that this review could be useful for stimulating further research of FBT.
... The intake of flavonoid containing foods can vary depending on the culinary habits of different countries. For instance, soybean consumption has been historically associated with oriental cultures or tea consumption is higher in countries such as United Kingdom, Ireland or Turkey, among others (Sanlier, Atik, & Atik, 2018;Shukla et al., 2016). ...
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Inflammation plays a key role in diseases such as diabetes, asthma, cardiovascular diseases and cancer. Diet can influence different stages of inflammation and can have an important impact on several inflammatory diseases. Increasing scientific evidence has shown that polyphenolic compounds, such as flavonoids, which are found in fruits, vegetables, legumes, or cocoa, can have anti-inflammatory properties. Recent studies have demonstrated that flavonoids can inhibit regulatory enzymes or transcription factors important for controlling mediators involved in inflammation. Flavonoids are also known as potent antioxidants with the potential to attenuate tissue damage or fibrosis. Consequently, numerous studies in vitro and in animal models have found that flavonoids have the potential to inhibit the onset and development of inflammatory diseases. In the present review, we focused in flavonoids, the most abundant polyphenols in the diet, to give an overview of the most recent scientific knowledge about their impact on different inflammatory diseases.
... Ayurvedic herbs have large quantities of GA [26,30,31]. Experimentally, GA has been documented to produce anti-hyperlipidemic, cardioprotective, anti-diabetic activity [32,33]. Furthermore, GA has potential neuroprotective action due to mono and poly-targeted actions [34,35]. ...
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The present study has been investigated the role of gallic acid (GA) in paclitaxel-induced neuropathic pain. The neuropathic pain was developed with paclitaxel (PT: 2 mg/kg, i.p.) administration in mice. GA (20 and 40 mg/kg) and pregabalin (PreG: 5 mg/kg) were administered intravenously for 10 consecutive days. The neuralgic sensations were investigated by assessing various pain tests like acetone drop, pinprick, plantar, tail flick, and tail pinch test. Mice pain behaviors were evaluated on 0, 4th, 8th, 12th and 16th days. The levels of sciatic nerve thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH), superoxide anion, calcium, myeloperoxidase (MPO), and TNF-α were estimated. Treatment of GA and PreG attenuate PT induced thermal &mechanical hyperalgesia and allodynia symptoms along with the reduction of TBARS, total calcium, TNF-α, superoxide anion, and MPO activity levels; and decreased GSH level. Therefore, it has been concluded that GA has potential neuroprotective actions against PT induced neuropathic pain due to it's anti-oxidant, anti-inflammation and regulation of intracellular calcium ion concentration.
... Studies found that white tea had higher levels of tea polyphenols and better antioxidant activity than black tea [60]. White tea could exhibit antidiabetic activity by reducing insulin resistance, hyperlipidemia, and oxidative stress [61]. Additionally, white tea lowered blood sugar level by increasing insulin sensitivity and the synthesis of liver glycogen in T2DM rats [62]. ...
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Diabetes mellitus has become a serious and growing public health concern. It has high morbidity and mortality because of its complications, such as diabetic nephropathy, diabetic cardiovascular complication, diabetic neuropathy, diabetic retinopathy, and diabetic hepatopathy. Epidemiological studies revealed that the consumption of tea was inversely associated with the risk of diabetes mellitus and its complications. Experimental studies demonstrated that tea had protective effects against diabetes mellitus and its complications via several possible mechanisms, including enhancing insulin action, ameliorating insulin resistance, activating insulin signaling pathway, protecting islet β-cells, scavenging free radicals, and decreasing inflammation. Moreover, clinical trials also confirmed that tea intervention is effective in patients with diabetes mellitus and its complications. Therefore, in order to highlight the importance of tea in the prevention and management of diabetes mellitus and its complications, this article summarizes and discusses the effects of tea against diabetes mellitus and its complications based on the findings from epidemiological, experimental, and clinical studies, with the special attention paid to the mechanisms of action.
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Herbal Teas prepared from leaves, roots, fruits and flowers of different herbs contain many useful nutrients that may be a good replacement for medicating of certain specific diseases. These herbal teas are very rich in poly-phenols so these are very much significant for their antioxidant, anti-inflammation, anticancer, anticardiovascular, antimicrobial, antihyperglycemic, and antiobesity properties. Medical chronic conditions such as cardiovascular disease, cancer, Alzheimer’s disease, Parkinson’s disease, constipation, diabetes and bed wetting in children can be easily cured by the use of these herbal teas in regular and moderate amounts. This Review focuses on the diverse constituents of herbal tea due to which it can be an attractive alternative toward promoting human health.
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Catechins belong to the group of flavonoids. Numerous studies show that consuming foods rich in catechins such as vegetables, fruits and especially teas may decrease the risk of developing various diseases. Therefore, we present in this compilation a critical and detailed analysis of the works published in the last six years and a guide for the reader with the main analytical techniques of quantification, in vitro and in vivo biological activities, the mechanisms of action in the organism and the bioaccessibility in treating the gastrointestinal effects of catechins from different matrices. The information presented in this review is important for a broad understanding of benefits that catechins can bring to human health and can be taken as an example for the study of new matrices, new effects and possible forms of application, such as dietary supplements or functional food ingredients for health promotion and the reduced risk for developing diseases. This article is protected by copyright. All rights reserved.
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White tea is a special tea product with increasing market demand. The assessment of white tea quality is mainly based on panel sensory by sensory evaluation experts, which is time costly and is limited by many uncertainties. This study established a rapid and accurate method for classification of white teas produced from buds and young leaves and that produced from mature leaves and shoots using near-infrared spectroscopy (NIR). Back propagation neural network modelling and support vector machine (SVM) modelling were compared with six pre-processing methods. The best performance was provided by SVM with particle swarm optimization combined with Savitzky-Golay filter pre-processing method, achieving the accuracy of 98.92% in test samples. The NIR-related chemical compounds of two categories of white teas produced from fresh leaves with different maturity were analyzed, including catechins, alkaloids, amino acids and flavonol glycosides. Compared with chemical component concentration, NIR absorbance had a distinct advantage in quick classification of white teas based on the principal components analysis. In addition, the sensory characteristics of two categories white teas produced from fresh leaves with different maturity were also assessed by panelist. The result showed that characteristics of "umami-like" and "smooth" were more likely present in white teas produced from buds and young leaves, while "woody" and "coarse" characteristics were usually present in white teas produced from mature leaves and shoots. Thus, NIR technique is a rapid and reliable method for discrimination of white teas produced from fresh leaves with different maturity, and is a potential method to discriminate sensory characteristics of white teas.
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Bioactive dietary polyphenols have health benefits against a variety of disorders, but some benefits of polyphenols may be not directly related to them but rather to their metabolites. Recently, we have identified the brain-available phenol glucuronide metabolite deoxyrhapontigenin-3-O-β-d-glucuronide (5) in perfused rat brains following subacute treatment with the stilbene resveratrol (1). However, the role of such a metabolite in the neuroprotective activity of resveratrol (1) is not understood, in part due to the noncommercial availability of 5 for performing biological evaluation in animal models of Alzheimer's disease or other neurological disorders. Here, we describe a concise chemical synthesis of deoxyrhapontigenin-3-O-β-d-glucuronide (5) and its precursor 4-O-Me-resveratrol (2), accomplished in four and six steps with 74 and 21% overall yields, respectively, starting from commercially available 3,5-dihydroxybenzaldehyde. Pivotal reactions employed in the synthesis include the palladium-catalyzed C-C coupling between 3,5-di-tert-butyldiphenylsilyloxystyrene and p-iodoanisole in the presence of tributylamine and the acid-catalyzed glucuronidation between the trichloroacetimidate-activated glucuronic acid and 4-O-Me-resveratrol.
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Storage has a dramatic influence on the chemical composition, sensory qualities, biological activity, and therefore the commercial value of white tea. In this study, the metabolites in white teas stored for 1, 3, 7, and ≥ 10 years were comprehensively compared by a nontargeted metabolomics investigation. Most metabolites, including catechins, flavonol/flavone glycosides, amino acids, nucleosides, organic acids, aroma precursors, lipids, and carbohydrates, decreased with increasing storage duration, while 8-C N-ethyl-2-pyrrolidinone-substituted flavan-3-ols (EPSFs) and pyroglutamic acid increased. The absolute quantifications of 24 storage-related compounds combined with linear regression analysis showed that a panel of 5 indexes based on EPSFs has a good predictive ability for the storage duration of white teas (correlation coefficients were 0.9294 and 0.8812 in the model and test sets, respectively). The errors between the predicted and the actual storage durations ranged from -1.75 to 1.84 years for the white teas stored for <10 years.
Chapter
These studies include some novel cold unit operation applied on bioactive foods. There are some novel cold unit operations applied on bioactive foods like fish, pollen, and white in literature. In this regard, the preservative effects of novel low-temperature withering, brewing, smoking, brining, and Low-Temperature High-Velocity drying application on bioactive components of some bioactive foods were discussed. As bioactive foods, the white tea, bee pollen, fish and some common fruits were discussed. Accordingly, we explained some important preservative effects of novel low-temperature unit operation application on some bioactive components like as ω-3 fatty acid, phenol components, volatile content and vitamins.
Article
In this study, metabolomics and proteomics were employed to investigate the change mechanism of nonvolatile compounds during white tea processing. A total of 99 nonvolatile compounds were identified, among which the contents of 13 free amino acids, caffeine, theaflavins, 7 nucleosides and nucleotides, and 5 flavone glycosides increased significantly, while the contents of theanine, catechins, theasinesins, 3 proanthocyanidins, and phenolic acids decreased significantly during the withering period. The results of proteomics indicated that the degradation of proteins accounted for the increase in free amino acid levels; the weakened biosynthesis, in addition to oxidation, also contributed to the decrease in flavonoid levels; the degradation of ribonucleic acids contributed to the increase in nucleoside and nucleotide levels during the withering period. In addition, the drying process was found to slightly promote the formation of white tea taste. Our study provides a novel characterization of white tea taste formation during processing.
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The utilization of fuzzy logic in WSNs is demonstrated to be a promising procedure since it permits joining and assessing various parameters in an effective way. Fuzzy logic is a decent methodology because of the execution prerequisites can be effectively supported by sensor hubs, while it can improve the general system execution. This paper studies the robust H∞ control considering time delay and packet loss related uncertainty in wireless sensor network system based on the basic theory of intelligent fuzzy systems. The model of a wireless sensor network with questionable time lag and packet loss is given first. The stability of the system is proved by the augmented Lyapunov functional and the linear matrix inequality (LMIs) method, with its demonstrated H∞ property. In order to solve the uncertain time delay and packet loss, the memory robust H∞ controller is proposed based on LMIs. Numerical examples and simulation results examines the potency of the presented method in solving the delay and packet loss of wireless sensor networks as well as the accuracy and precision of the system.
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The aroma changes in instant white tea resulting from β-glucosidase treatment was investigated by quantitative descriptive analysis (QDA), gas chromatography-mass spectrometry (GC–MS), odour activity value analysis (OAV), aroma reconstruction and omission tests. The grassy, floral and sweet notes increased significantly (P < 0.05), and the roasted note decreased significantly (P < 0.05) upon β-glucosidase treatment. Quantitative analysis showed that the concentrations of benzaldehyde, benzeneacetaldehyde, (Z)-3-hexen-1-ol, linalool, phenylethyl alcohol, cis-linalool oxide, trans-linalool oxide, hexanol, hotrienol and (E)-2-hexen-1-ol increased significantly (P < 0.05) after treatment; however, (Z)-3-hexen-1-ol isomerized to (E)-2-hexen-1-ol. OAV analysis, aroma reconstruction and the omission test showed that the grassy, floral and sweet notes increased as the (Z)-3-hexen-1-ol, cis/trans-linalool oxide and benzeneacetaldehyde increased, whereas the roasted note declined under the same conditions. The enzymatic hydrolysis of glycosidic precursors and the auto-isomerization of volatile compounds provide new information for understanding how β-glucosidase treatment improves the aroma of tea products.
Article
Ethnopharmacological relevance Diabetic kidney damage (DKD) is one of the most common complications of diabetes, which is known as a chronic inflammatory kidney disease caused by persistent hyperglycemia. White tea was originally used as a folk medicine to treat measles in ancient China. What arouses our interest is that there is a traditional method to treat diabetes with white tea taken from over 30-year-old tree of Camellia sinensis L. However, there are few reports on the renal protection of white tea. Aim of the study: This present study was designed to study the potential protective effects of white tea (WT) and old tree white tea (OTWT) on high-fat-diet (HFD) combined with streptozotocin (STZ)-induced type 2 diabetic mice to explore the possible mechanism of WT/OTWT against DKD. Materials and methods C57BL/6 mice were randomly divided into four groups: NC, T2D, WT (400 mg/kg·b.w, p.o.), OTWT (400 mg/kg·b.w, p.o.). Diabetes was established in all groups except NC group, by six weeks of HFD feeding combined with STZ (50 mg/kg, i.p.) for 3 times, treatments were administered for six weeks and then all the animals were decapitated; kidney tissues and blood samples were collected for the further analysis, including: levels of insulin, lipid metabolism (TG, TC, HDL, LDL, FFA), antioxidative enzymes (catalase (CAT), super oxide dismutase (SOD), glutathione peroxidase (GPx)), blood urea nitrogen (BUN) and creatine, inflammatory cytokines (TNF-α, IL-1β, COX-2, iNOS, MCP-1), advanced glycation end products (AGE), receptor of AGE (RAGE), Nrf2, AMPK, SIRT1, and PGC-1α. H&E, PAS and Masson staining were performed to examine the histopathological alterations of the kidneys. Results Our data showed that WT and OTWT reversed the abnormal serum lipids (TG, TC, HDL, LDL, FFA) in T2D mice, upregulated antioxidative enzymes levels (CAT, SOD, GPx) and inhibit the excessive production of proinflammatory mediators (including MCP-1, TNF-α, IL1β, COX-2 and iNOS) by varying degrees, and OTWT was more effective. In histopathology, OTWT could significantly alleviate the accumulation of renal AGE in T2D mice, thereby improving the structural changes of the kidneys, such as glomerular hypertrophy, glomerular basement membrane thickening and kidney FIbrosis. Conclusions Both WT and OTWT could alleviate the diabetic changes in T2D mice via hypoglycemic, hypolipidemic, anti-oxidative and anti-inflammatory effects, while OTWT was more evident. OTWT could prominently alleviate the accumulation of AGE in the kidneys of T2D mice, thereby ameliorating the renal oxidative stress and inflammatory damage, which was associated with the activation of SIRT1/AMPK pathway.
Article
Tea catechins are a group of flavonoids that show many bioactivities. Catechins have been extensively reported as a potential treatment for skin disorders, including skin cancers, acne, photoaging, cutaneous wounds, scars, alopecia, psoriasis, atopic dermatitis, and microbial infection. In particular, there has been an increasing interest in the discovery of cosmetic applications using catechins as the active ingredient because of their antioxidant and anti-aging activities. However, active molecules with limited lipophilicity have difficulty penetrating the skin barrier, resulting in low bioavailability. Nevertheless, topical application is a convenient method for delivering catechins into the skin. Nanomedicine offers an opportunity to improve the delivery efficiency of tea catechins and related compounds. The advantages of catechin-loaded nanocarriers for topical application include high catechin loading efficiency, sustained or prolonged release, increased catechin stability, improved bioavailability, and enhanced accumulation or targeting to the nidus. Further, various types of nanoparticles, including liposomes, niosomes, micelles, lipid-based nanoparticles, polymeric nanoparticles, liquid crystalline nanoparticles, and nanocrystals, have been employed for topical catechin delivery. These nanoparticles can improve catechin permeation via close skin contact, increased skin hydration, skin structure disorganization, and follicular uptake. In this review, we describe the catechin skin delivery approaches based on nanomedicine for treating skin disorders. We also provide an in-depth description of how nanoparticles effectively improve the skin absorption of tea catechins and related compounds, such as caffeine. Furthermore, we summarize the possible future applications and the limitations of nanocarriers for topical delivery at the end of this review article.
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White tea has been of increasing public interest worldwide owing to its health benefits. Based on 2 years of surveillance, the long-term and cumulative chronic exposure risks of pesticide residues through white tea drinking were assessed for different subpopulations in Fujian, China. Twenty-five different pesticides were found, and 74.8% of samples contained at least one pesticide residue. The most frequently detected pesticide was bifenthrin with detection rates of 61.6%. Risk assessment was performed using both the deterministic approach and semiprobabilistic model under the best-case and the worst-case scenarios. The results demonstrated that the dietary risks were extremely low for six different subpopulations in which the risks for adults over the age of 41 were relatively higher. The risk ranking scheme indicated that isocarbophos and triazophos were considered to be of medium risk. The different use suggestions for the 25 positive pesticides are proposed to further minimize the exposure risk to consumer health. Practical Application Tea is the second most popular nonalcoholic beverage throughout the world. Pesticides are used to improve the yield of tea. Pesticide residues in tea could be one of the exposure pathways for consumers. Monitoring residual levels and assessing the health risk assessment in tea are thus in an urge.
Article
BACKGROUND In the present work, an extraction method affected by sonication intensity (40, 70, and 100%), sonication time (5, 10, and 15 min), and different solvents (ethanol, methanol, and a combination of ethanol/methanol) was optimized to extract the white tea with the greatest polyphenolic compounds by using response surface methodology. To prepare the Nano-liposomal vesicles, phospholipids and cholesterol in various proportions (60:0, 40:20, 30:30, and 20:40) were applied based on thin-film hydration and ultrasound method. The Nano-capsules enriched in bioactive compounds were examined through particle characteristics, encapsulation efficiency, morphological analysis, thermal properties, and FTIR. RESULTS The observations showed that the extraction yield highly depended on the type of solvent with varying permeability, sonication time and power. The highest total phenolic content (68.38 mg GA/g) and free radical scavenging activity (77.65%) were observed in the following optimal conditions: 70% for sonication intensity, 15 min for sonication time, and methanol as solvent. Characteristics of nanoliposomes within a compositional ratio of lecithin/Cholesterol (40:20) having a zeta potential of -56 ± 0.01 mV, WTE samples average particle diameter of 82.20 ± 0.08, microencapsulation efficiency of 76.5% ± 0.081, PDI of 0.06± 0.02, and span value of 0.69 ± 0.03 are used as the optimal formulation for microencapsulation of antioxidant white tea extract. Results displayed an increment in thermal stability of liposomal WTE samples compared to other samples. CONCLUSION The findings of the present study indicated that Nano-liposome was an effective technology to coat the white tea extract as well as to increase its stability and thermal properties. This article is protected by copyright. All rights reserved.
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South African rooibos (Aspalathus linearis) tea is globally consumed for its health benefits and caffeine free nature, but no information is available on the neuroprotective capacity of (unfermented) green rooibos....
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Hyperuricemia is an abnormal purine metabolic disease that occurs when there is an excess of uric acid in the blood, associated with cardiovascular diseases, hypertension, gout, and renal disease. Dietary intervention is one of the most promising strategies for preventing hyperuricemia and controlling uric acid concentrations. Tea (Camellia sinensis) is known as one of the most common beverages and the source of dietary polyphenols. However, the effect of tea on hyperuricemia is unclear. Recent evidence shows that a lower risk of hyperuricemia is associated with tea intake. To better understand the anti-hyperuricemia effect of tea, this review first briefly describes the pathogenesis of hyperuricemia and the processing techniques of different types of tea. Next, the epidemiological and experimental studies of tea and its bioactive compounds on hyperuricemia in recent years were reviewed. Particular attention was paid to the anti-hyperuricemia mechanisms targeting the hepatic uric acid synthase, renal uric acid transporters, and intestinal microbiota. Additionally, the desirable intake of tea for preventing hyperuricemia is provided. Understanding the anti-hyperuricemia effect and mechanisms of tea can better utilize it as a preventive dietary strategy.HighlightsHigh purine diet, excessive alcohol/fructose consumption, and less exercise/sleep are the induction factors of hyperuricemia.Tea and tea compounds showed alleviated effects for hyperuricemia, especially polyphenols.Tea (containing caffeine or not) is not associated with a higher risk of hyperuricemia.Xanthine oxidase inhibition (reduce uric acid production), Nrf2 activation, and urate transporters regulation (increase uric acid excretion) are the potential molecular targets of anti-hyperuricemic effect of tea.About 5 g tea intake per day may be beneficial for hyperuricemia prevention.
Article
Tea is consumed widely around the world owing to its refreshing taste and potential health benefits. However, drinking tea is considered a major route for dietary aluminum exposure in areas where tea consumption is relatively large. To assess the health risk associated with drinking tea, the contamination level of aluminum was determined in 81 tea samples. The transfer rate of aluminum during tea brewing was investigated. Then based on the site-specific exposure parameters such as consumption data and body weight for six different subpopulations in Fujian, the exposure risks were estimated using a probabilistic approach. Results demonstrate that the contents of aluminum in green tea, white tea, oolong tea, and black tea were significantly different according to the one-way ANOVA analysis (p<0.05). The transfer rate of aluminum were 32.6%, 31.6%, 26.3%, and 14% for white tea, black tea, oolong tea, and green tea, respectively. With respect to the oral reference dose, the exposure of inhabitants in Fujian to aluminum through drinking tea is under control (even at the 99th percentile).
Article
Tea is one of the biggest categories of modern non‐alcoholic beverages with health benefits. Through different processes, tea products are divided into six main types: green tea, yellow tea, white tea, oolong tea, black tea, and dark tea. Metabolomics is helpful for the comprehensive, accurate, and rapid determination of tea metabolites in different types of tea products and tea processing materials. It has been widely applied in studying the relationship of tea metabolites and its quality. Therefore, it is necessary to summarize the application of metabolomics in tea. In this review, we described and summarized 1) the main metabolites of six types of tea and their implications on tea quality with emphasis on the content differences of the main metabolites in different types of tea; 2) the research on optimizing the key processing steps of six types of tea based on metabolomics and the discussion of various new strategies for effectively improving their quality; and 3) the advanced approach to characterize and distinguish different grades of tea products via metabolomics. The current review offers guidance for the improvement of tea quality by metabolomics and its potential challenges.
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Cadmium contamination is a serious environmental issue and its detection is important. In this study, tea residue after pretreatment by the deep eutectic solvent of choline chloride/urea was used for one-pot solvothermal synthesis of carbon dots (CDs) applied in cadmium detection for the first time. The effect of choline chloride/urea molar ratio, reaction period, and reaction temperature on the CDs synthesis was learned and a promising synthesis system (choline chloride/urea molar ratio of 1:2, reaction at 200 °C for 8 h) was built. Under this reaction condition, the CDs yield and the quantum yield were 2.25% and 16.99%, respectively. The optical properties and structure of CDs were learned by fluorescence spectrophotometer, UV–vis spectrophotometer, transmission electron microscope (TEM), field emission scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffractometer (XRD), and X-ray photoelectron spectrometer (XPS). According to the characterization, the CDs had a strong peak at 410 nm with the corresponding excitation wavelength of 330 nm and contained various functional groups including hydroxyl, amino, and carbonyl. The CDs were suitable for cadmium detection by a linear standard curve with a high correlation coefficient (R² =0.99). Overall, this study offers a promising method for utilization of waste biomass (tea residue) for fluorescent materials (CDs) production.
Article
A high-fat diet results in obesity through white fat accumulation. Although tea extracts alleviate lipid metabolism disorders and decrease white fat accumulation, the mechanisms underlying the therapeutic actions of different types of Chinese tea are unclear. We established murine model of obesity by feeding the mice with high fat diet (HFD), and treated them with atorvastatin (positive control) or the water extracts (WEATs) of different tea types. The food and water intake, body weight gain, white fat accumulation, triglyceride (TG) and total cholesterol (TC) levels were evaluated to assess the effects of the WEATs on obesity. And the levels of the lipid metabolism enzymes p-AMPK, CPT-1A and FAS, and the pro-inflammatory factors iNOS and IL-6 were determined. The WEATs, not only reduced the body weight and white fat accumulation in the HFD-induced obese mice, but also relieved hepatic steatosis. Comparing the effects of six kinds of tea showed that white tea has the best anti-obesity effects. Yellow tea and raw pu-erh tea significantly upregulated p-AMPK, green tea, white tea and raw pu-erh tea markedly inhibited FAS, and white tea, yellow tea and oolong tea upregulated CPT-1. Therefore, it is possible that white tea, yellow tea and oolong tea inhibit obesity by increasing energy expenditure and fatty acid oxidation, while green tea, white tea and raw pu-erh tea exert their effects by inhibiting fatty acid synthesis. In addition, the WEATs also significantly decreased the levels of IL-6, while green tea, yellow tea and oolong tea significantly inhibited iNOS. Different types of tea have the specific chemical composition, and can regulate different lipid metabolism related protein. In conclusion, despite variations in composition and mechanism of action, tea is a potent anti-obesity agent.
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Amphotericin B is a fungicidal substance that is treatment of choice for most systemic fungal infections affecting immunocompromised patients. However, severe side effects have limited the utility of this drug. The aim of this study was to evaluate the antifungal effect of the combination of amphotericin B with black tea or white tea and protective of citotoxic effect. The present study shows that white and black teas have additive effects with amphotericin B against some species Candida. In addition, the combination of white and black tea with amphotericin B may reduce the toxicity of amphotericin B to red blood cells. Our results suggest that white and black tea is a potential agent to combine with amphotericin for antifungal efficacy and to reduce the amphotericin dose to lessen side effects.
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Çay, bileşiminde bulunan biyoaktif maddeler nedeniyle pek çok araştırıcının dikkatini çeken bir içecektir. Son yıllarda özellikle yeşil çayın sağlık üzerine etkilerini inceleyen yoğun araştırmalar yapılmaktadır. Genellikle mikrobiyal sistemler ile memeli hücre sistemleri ve deney hayvanları üzerinde gerçekleştirilen bu çalışmalarda, yeşil çayın mide, kolon, meme, prostat ve pankreas kanserleri gibi değişik kanser türlerini, kalp damar hastalıklarını, iltihabi ve nörodejeneratif hastalıkları önleyici ve tedaviyi destekleyici etki gösterebileceği bildirilmektedir. Bu derlemede konuyla ilgili son yıllarda yapılan araştırma sonuçları irdelenecektir.
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Abstract Tea (Camellia sinensis) has a long history of medicinal use in the world. The chemical components of tea mainly consist of polyphenols, proteins, polysaccharides, chlorophyll, alkaloids, and so on. Great advances have been made in chemical and bioactive studies of catechins and polyphenols from tea in recent decades. However, the polysaccharides from tea materials have received much less consideration than that of polyphenols. The number of relevant publications on the polysaccharides from tea leaves and flowers has increased rapidly in recent years. This mini-review summarizes the structure-function relationship of polysaccharides from tea leaves and flowers. The application of purified polysaccharides from tea material as functional or nutritional foods was still little. It will help to develop the function foods with tea polysaccharides and better understand the structure-bioactivity relationship of tea polysaccharides.
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For centuries tea is a popular beverage and has also been used as medicine. While green and black teas are very healthy, white tea is a superb tonic and one of the nature's great gifts. It is the least processed tea and has the highest antioxidant levels as compare to black and green tea. A supreme drink for health ―white tea‖ plays an important role in preventing diseases and disorders. White tea protects against cancer, heart disease, and stroke, the leading causes of death in the industrial world, as well as numerous other conditions. The symptoms of illness reduce and it promotes recovery. White tea strengthens the circulatory, immune systems as well as bones and teeth, and builds healthy skin. White tea has many other benefits to offer like it may reduce blood sugar and help prevent symptoms of diabetes to elevate. It reduces stress and increases energy. The aim of this present article is to enlist various health benefits of white tea especially its role in prevention of cardio-vascular diseases, cancer, obesity, skin and eye disorders. An attempt is also made to highlight the history, contents, manufacturing, production, varieties as well as the past and the ongoing researches on white tea related to the clinical uses of white tea.
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Tea is one of the most widely consumed beverages in the world, next to water. It can be categorized into three major types, depending on the level of fermentation, i.e., green and white (unfermented), oolong (partially fermented) and black (fermented) tea. Each type of tea has a distinct composition, dependent on how the leaves are processed, as well as maturation, geographical location and agricultural practices. White tea (WT), the least processed tea, is one of the less studied and is ascribed to have the highest content of phenolic compounds. Tea polyphenols, especially catechin derivatives, are potent antioxidant agents, with positive effects on human health. Antioxidant components have aroused great interest because of their ability to scavenge free radicals, thereby inhibiting oxidative stress. During the past years, oxidative damage induced by reactive species has been linked to the development of several human diseases such as cardiovascular diseases, diabetes mellitus, neurodegenerative disorders and certain types of cancer. Therefore, tea antioxidants may be of great value in preventing the onset and/or the progression of oxidative stress mediated diseases, when endogenous defences are insufficient against reactive species. The possible beneficial health effects of WT are being investigated and have received considerable attention in recent years. In this review, we aim to explore the new findings concerning WT effects on health.
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An overview is given on the manufacture of the different types of tea along with the most important phenolics present in tea and methods of analysis. Compositional data are presented for green, white and black teas. A differentiation of green and black tea by using the ratio between total phenolics and sum of the major catechins seems to be feasible. For white tea there is no general accepted definition. Possible approaches are geographic origin, the botanical variety and the manufacture or the appearance. The differentiation between green and white teas by the ratio mentioned above is not possible. Eswird eine Übersicht über die Teemanufaktur und die resultierenden Arten von Tee gegeben, begleitet von einer Übersicht über einige wichtige Inhaltsstoffe (Flavanole, Zusammenstellung analytischer Methoden zur Bestimmung von (Poly)-phenolen und Daten über grüne, schwarze undweiße Tees). Derzeit scheint eine Differenzierung von grünem und schwarzem Tee über das Flavanol:Gesamtphenolverhältnis möglich. Für weißen Tee gibt es derzeit keine allgemein akzeptierte Definition. Mögliche Ansätze für diese sind die geographische Herkunft, die botanische Varietät oder die Art der Herstellung. Eine Differenzierung durch das Flavanol:Gesamtphenolverhältnis von grünem und weißen Tee ist nicht realistisch.
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Tea polyphenols, especially the catechins, are potent antimicrobial and antioxidant agents, with positive effects on human health. White tea is one of the less studied teas but the flavour is more accepted than that of green tea in Europe. The concentrations of various catechins in 13 different kinds of infusion were determined by capillary electrophoresis. The total polyphenol content (Folin–Ciocalteu method), the trolox equivalent antioxidant capacity (TEAC value determined with the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation) and the inhibitory effects of infusions on the growth of some microorganisms were determined. Five different infusions (black, white, green and red teas and rooibos infusion) were added to a model food system, comprising a sunflower oil-in-water emulsion containing 0% or 0.2% bovine serum albumin (BSA), and the oxidative stability was studied during storage at 37 °C. Oxidation of the oil was monitored by determination of the peroxide value.The highest radical-scavenging activity observed was for the green and white teas. Emulsions containing these extracts from these teas were much more stable during storage when BSA was present than when it was not present, even though BSA itself did not provide an antioxidant effect (at 0.2% concentration). Rooibos infusion did not show the same synergy with BSA. Green tea and white tea showed similar inhibitions of several microorganisms and the magnitude of this was comparable to that of the commercial infusion 2 (C.I.2), “té de la belleza”. This tea also had an antioxidant activity comparable to green tea.
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The medicinal effects of tea have a history dating back almost 5000 years. The chemical components of green tea chiefly include polyphenols, caffeine and amino acids. Tea also contains flavonoids, compounds reported to have anti-oxidant properties having many beneficial effects. Tea flavonoids reduce inflammation, have antimicrobial effects and prevent tooth decay. Consumption of tea may have diuretic effects due to the caffeine. A related compound found in tea is theophylline, a licensed medicine for the treatment of respiratory diseases such as asthma. Today’s computer-driven world can generate complicated lifestyle-related disorders and consumption of certain natural product like tea may very well replace the ill-effects of chemical drugs leading to a safer world with happier life. The paper is an overview of revealing all such ethno medicinal research efforts throughout the world over the times.
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Epidemiological studies beginning in the 1990s have reported that intake of quercetin, a polyphenolic flavonoid found in a wide variety of plant-based foods, such as apples, onions, berries, and red wine, is inversely related to cardiovascular disease. More recent work using hypertensive animals and humans (>140 mm Hg systolic and >90 mm Hg diastolic) indicates a decrease in blood pressure after quercetin supplementation. A number of proposed mechanisms may be responsible for the observed blood pressure decrease such as antioxidant effects, inhibition of angiotensin-converting enzyme activity, and improved endothelium-dependent and -independent function. The majority of these mechanisms have been identified using animal models treated with quercetin, and relatively few have been corroborated in human studies. The purpose of this review is to examine the evidence supporting the role of quercetin as a potential therapeutic agent and the mechanisms by which quercetin might exert its blood pressure-lowering effect.
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This review summarizes the literature on the association between tea consumption and cognitive health in late life. Population-based studies reviewed in this article suggest that tea drinking has beneficial effects on cognitive function of elderly persons. However, a cause-effect relationship between tea consumption and cognitive decline and dementia could not be drawn given inconsistent findings from only two longitudinal cohort studies. The neuroprotective effects of tea consumption could be due to catechins, L-theanine and other compounds in tea leaves. More longitudinal observational study is needed. Information on life-time tea consumption and blood concentrations of catechins and L-theanine could be collected in future studies.
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Coffee has been hypothesized to have pro- and anticarcinogenic properties, whereas tea may contain anticarcinogenic compounds. Studies assessing coffee intake and pancreatic cancer risk have yielded mixed results, whereas findings for tea intake have mostly been null. Sugar-sweetened carbonated soft drink (SSB) intake has been associated with higher circulating levels of insulin, which may promote carcinogenesis. Few prospective studies have examined SSB intake and pancreatic cancer risk; results have been heterogeneous. In this pooled analysis from 14 prospective cohort studies, 2,185 incident pancreatic cancer cases were identified among 853,894 individuals during follow-up. Multivariate (MV) study-specific relative risks (RR) and 95% confidence intervals (CI) were calculated using Cox proportional hazards models and then pooled using a random-effects model. No statistically significant associations were observed between pancreatic cancer risk and intake of coffee (MVRR = 1.10; 95% CI, 0.81-1.48 comparing ≥900 to <0 g/d; 237g ≈ 8oz), tea (MVRR = 0.96; 95% CI, 0.78-1.16 comparing ≥400 to 0 g/d; 237g ≈ 8oz), or SSB (MVRR = 1.19; 95% CI, 0.98-1.46 comparing ≥250 to 0 g/d; 355g ≈ 12oz; P value, test for between-studies heterogeneity > 0.05). These associations were consistent across levels of sex, smoking status, and body mass index. When modeled as a continuous variable, a positive association was evident for SSB (MVRR = 1.06; 95% CI, 1.02-1.12). Conclusion and Impact: Overall, no associations were observed for intakes of coffee or tea during adulthood and pancreatic cancer risk. Although we were only able to examine modest intake of SSB, there was a suggestive, modest positive association for risk of pancreatic cancer for intakes of SSB.
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The present study was conducted to unravel the comparative efficacy of White Tea (WT) and Epigallocatechin gallate (EGCG) in affording protection against benzo (a) pyrene (BaP) induced hepatotoxicity. The animals were randomly divided into six groups viz., normal control (NC), BaP, EGCG, WT, WT + BaP and EGCG + BaP treated. 50 mg/kg of BaP was given orally twice a week for 4 weeks. WT extract (1%) and EGCG (1% WT equivalent) were given on alternate days for 12 weeks (4 weeks prior, during and after BaP treatment). BaP treated animals showed a significant increase in the activities of biomarkers in conditions of inflammatory, oxidative and liver stress. However, the levels of these biomarkers were decreased appreciably upon treatment with WT and EGCG. Interestingly, no marked differences in these indices were experienced in animals treated with either EGCG or WT. Further, BaP treatment decreased significantly the amount of endogenous antioxidants which however were increased substantially when WT and EGCG were supplemented to BaP treated animals. BaP induced hepatic histoarchitectural alterations also showed an appreciable improvement when these animals were supplemented with WT or EGCG. The present study thus recommends the usefulness of WT extract vis-a -vis EGCG in mitigating BaP induced hepatic dysfunctions.
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The use of nontoxic biological compounds in the synthesis of nanomaterials is an ecofriendly and cost-effective approach in nanotechnology. The present work was carried out to develop silver nanoparticles (Ag-NPs) by a green method using white tea (Wt) extract as reducing agent for reduction of silver nitrate as silver precursor into the lamellar space of inorganic polymer montmorillonite (Mt) as an effective protective reagent and support as well. The bioformed Wt/[email protected] nanocomposite (NCs) was compared with pure biosynthesized Wt/Ag-NPs under free stabilizer condition and effect of Mt stabilizer on antioxidant, cytotoxicity and structural properties were also investigated. The prepared Wt/Ag-NPs and Wt/[email protected] were characterized by UV–vis spectroscopy, FTIR, XRD, TEM, SEM and EDX. The interlamellar space limits were without many changes, therefore Ag-NPs formed on the exterior surface of Mt. The XRD study showed that the particles are crystalline structure in nature, with a facecentered cubic (fcc) structure. The TEM result shows the bioformed Ag-NPs are spherical in shapes with mean particle size of 19.77 ± 3.82 for Wt/Ag-NPs and 15.87 ± 2.38 nm for Wt/[email protected] In vitro cytotoxicity studies on MOLT-4 cells, a dose dependent toxicity with non-toxic effect of concentration below 40 μg/mL was shown. The outcome shows that IC50 of our green synthesized Wt/[email protected] was 0.0039 in comparison to 2.13329 for Doxorubicin and 0.013 μM for Cisplatin which is much better than IC50 of these anticancer drugs and more active than them for MOLT-4 cell line. Antioxidant activity indicated that they can be applied as potential radical scavenger and also showed that DPPH activity increased in a dose dependent manner. The bio-synthesized nanoparticles can potentially useful in pharmaceutical and biomedical applications.
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Background: Treatment for type-2 diabetes mellitus focuses on the incretin hormone, Glucagon-Like Peptide-1 (GLP-1). However, it has a short half-life. Inhibition of the enzyme Dipeptidyl peptidase IV (DPP IV) required maintaining the active form of GLP-1. Based on the previous studies on the highest activity of DPP IV enzyme inhibition of white tea extract, this study conducted on the fraction of white tea extract using rat blood serum (ex vivo). Objectives: This study aims to evaluate the inhibitory activity of fraction from white tea extract. Methods: White tea leaves extracted with ethanol. The inhibitory activity determined by using rat blood serum as DPP IV enzyme source (ex vivo), AMC (7-amino 4-methyl coumarin) as fluorescence substrate of DPP IV and sitagliptin as the standard reference. The the cleavage of fluorescence reaction product observed by a microplate reader with λex = 360 nm and λem=460 nm at 37oC. Data expressed as mean ± SD and the IC50 value determined by nonlinear regression curve and fit using Prism Graph 7. Result: methanol fraction (250 μg/mL) has the greater inhibition percentage (50.487%), and the fraction of n-hexane and ethyl acetate are 32.417% and 36.541%. The methanol fraction IC50 value is 227 μg /mL. Conclusion: The methanol fraction is the most active to inhibit DPP IV enzyme.
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Aim: To compare the antimicrobial effect of black tea, green tea, white tea on Streptococcus mutans by tube dilution methods. Background: Medicinal plants have been a major source of therapeutic agents and cure diseases. In the present investigation comparative analysis of the potential antibacterial activity of aqueous extracts of white tea, black tea, green tea which were obtained by infusion of leaves. It was performed by using minimal inhibitory concentration and minimal bactericidal concentration against bacteria as Streptococcus mutans which is the potent initiator and leading cause of dental caries of world wide. Black tea is generally stronger in flavor than the less oxidized teas. Green tea is non-fermented tea which is valued for its medicinal properties. White tea contains the most antioxidants and also contains the poly phenols, phyto nutrients. Materials And Methods: In this experimental study black tea, green tea and white tea were used on the organism Streptococcus mutans to compare the antimicrobial effect by minimal inhibitory concentration and minimal bactericidal concentration. Reason: The extracts of black tea, green tea and white tea are found to hane unique antimicrobial properties. They are find to have more effectiveness on treating caries caused by S.mutans.
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Oolong tea (OT) is a traditional Chinese tea (Camellia sinensis) and is especially popular in south China. This review is to comprehensively summarize the miscellaneous research that has been done towards to the processing, phytochemistry, health benefit, and risk of OT. These literatures were carried out not only from different electronic databases but also from text books written in English, Japanese and Chinese, including those traditional records tracing back to the Tang Dynasty (A.D. 618–907). The full process OT producing is depicted below in this review. The phytochemistry of oolong tea has been comprehensively investigated. More than 100 chemical compositions have been isolated and identified. In health benefit, OT performs outstandingly in reducing obesity and controlling diabetes explained by modern pharmacological studies. (−)-Epigallocatechin-3-gallate (6) in OT prevention of cancerous cells developing. OT can also improve and reduce on heart and vascular disease, protect teeth and bone, function as anti-oxidative and antibacterial agents. This review also mentioned the risk, summarized briefly on various forms of toxicity and harmful associated with OT. In short, this review can provided a natural product library of OT, gave inspirations for further new garden systems, designed idea on quality, bioactivity-oriented screening. In addition, it is suggested more scientists and education is necessary to guarantee the stability and safety of drinking OT.
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Green tea has been consumed for centuries in Japan, China and Morocco. White tea, which is considered a variety of green tea, is mostly consumed in China and is very appreciated for its flavor. Currently the consumption of both teas has been extended to the Western countries even as a functional ingredient. A group of polyphenols called catechins highlights among their bioactive components, the most abundant being the (-) epigallocatechin gallate, with a high antioxidant power. Teas also contain other phenolic compounds such as gallic, caffeic, chlorogenic or cinnamic acids, quercetin and proanthocyanidols, caffeine, theophylline, L-theanine and minerals such as fluorine, manganese or chromium. Investigations have mainly been focused on their antioxidant potential and their implication in the prevention and treatment of degenerative diseases. Several studies have evaluated their role in cardiovascular diseases, body weight control, bone mass increase, protection against neurodegenerative diseases and improvement of type 2 diabetes, among other pathologies. The main points of controversy are the design and the interpretation of epidemiological and human intervention studies and the lack of information on catechins availability, metabolism and biotransformation. This review compiles and analyzes the latest peer-reviewed papers published from 2002 up to February 2017, including systematic reviews and meta-analyses
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Tea, one of the most widely consumed beverages in the world, is produced from the leaves of the plant Camellia sinensis L.. Tea has important physiological properties and potential health benefits due to the presence of compounds such as polyphenols, amino acids, vitamins, carbohydrates, caffeine, and purine alkaloids. Tea is produced in three types as green tea (unfermented), oolong tea (partially fermented), and black tea (fully fermented). Black tea is consumed worldwide, whereas green and oolong teas are consumed mainly in Asia and North Africa. The total tea production in the world consists of about 78% black tea, 20% green tea and
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In this work extraction kinetics of typical ingredients in representative white teas was investigated. Aqueous extraction of 4 epicatechins (EGC, EC, EGCG, ECG), 4 trans-catechins (GC, C, GCG, CG), gallic acid (GA) and caffeine at 65 °C, 75 °C, 85 °C, 95 °C respectively from Fuding Silver Needle (FSN), Fuding White Peony (FWP), Zhenghe Silver Needle (ZSN) and Zhenghe White Peony (ZWP) was examined. The total catechins, gallic acid, caffeine, EGCG, epicatechins, trans-catechins were compared in terms of rate, peak value, peak time and the extraction kinetics at different temperatures. It is exhibited that the contents of 8 catechins in ZWP, ZSN and FSN follow the order of EGCG > ECG > GC > EGC > GCG > CG > EC > C, and that in FWP is EGCG > ECG > EGC > GC > EC > GCG > CG > C. Structural transformation from epicatechins to trans-catechins and dissociation of gallic acid were observed during extraction by data analysis. Extraction kinetics over 240 min period were successfully modeled using Peleg's model with low MSR (0–2.232) and high R2 adj (0.903–0.999). Optimal extraction conditions (FSN(43.3 min, 95 °C); FWP(43.3 min, 95 °C); ZSN(53.8 min, 95 °C); ZWP(41.5 min, 95 °C)) were suggested by Peleg's model. As a result, this study will facilitate quality control of white tea during processing.
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White tea is considered the least processed form of tea and is reported to have a series of potent bioactivities, such as antioxidant, anti-inflammatory, anti-mutagenic, and anti-cancer activities. However, the chemical composition of white tea and the dynamic changes of the metabolites during the manufacturing process are far from clear. In this study, we applied a nontargeted metabolomics approach based on ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-QTOF/MS) to comprehensively profile the characteristic metabolites of white tea. There were significant differences in the content of amino acids, catechins, dimeric catechins, flavonol and flavone glycosides, and aroma precursors in white tea compared with green and black teas that were manufactured from the same fresh tea leaves. Furthermore, the dynamic changes of the metabolites in the tea samples with various withering durations of 0, 4, 8, 12, 16, 20, 24, 28, and 36 h were also profiled. This study offers a comprehensive characterization of the metabolites and their changes in white tea.
Article
The aim of the study was to generate compositional data for authentic white tea samples from China to serve as a starting point for a database and aid the definition of white teas. Quantitative data for the major catechins, hydrolysable tannins, phenolic acids, flavonol glycosides, alkaloids and theanine in 58 Chinese white teas were obtained based on HPLC methods Data for the major theaflavins in white teas are provided for the first time. Measurements of 29 metabolomics showed there were distinct differences among the different types of white teas such as silver needle white tea (BHYZ), white peony white tea (WP), ShouMei white tea (SM) and compressed brick white tea (CP). In our investigation, catechins, hydrolysable tannins, phenolic acids, theanine and caffeine had higher levels in early spring produced BHYZ than teas in late spring produced WP and autumn produced ShouMei. Theaflavins were found highest in mature autumn white tea samples, and lower in spring. Flavonol glycosides showed a different aglycone pattern. In early spring harvest BHYZ, kaempferol was the most abundant aglycone followed by quercetin and myricetin, while in autumn harvest ShouMei and CP samples, quercetin was most abundant followed by kaempferol and myricetin.
Article
Prediabetes represents a major risk factor for the development of type 2 diabetes mellitus (T2DM). It encompasses some, but not all, T2DM diagnostic criteria. Prediabetes has been recently associated with altered testicular function and increased testicular oxidative stress (OS). Tea is widely consumed and its anti-hyperglycaemic/antioxidant properties are known. This study aimed to evaluate whether white tea (WTEA) consumption by prediabetic rats could prevent testicular OS, preserving sperm quality. For that purpose, WTEA (presenting a high catechin content) was given to 30-day-old streptozotocin-induced prediabetic rats for 2 months. Testicular antioxidant potential and OS were evaluated, as well as sperm parameters, by standard techniques. WTEA consumption improved glucose tolerance and insulin sensitivity in prediabetic rats. Testicular antioxidant potential was increased by WTEA consumption, restoring protein oxidation and lipid peroxidation, although glutathione content and redox state were not altered. WTEA consumption improved sperm concentration and sperm quality (motility, viability and abnormality) was restored. Overall, WTEA consumption improved reproductive health of male prediabetic rats. Based on the study results, WTEA consumption appears to be a natural, economical and effective strategy to counteract the deleterious effects of prediabetes on male reproductive health, but further studies will be needed before a definitive recommendation is made. Copyright © 2015 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.
Article
Prediabetes is associated with cardiovascular diseases. We hypothesized that white tea (WTEA) consumption by prediabetic rats improved cardiac glycolytic and oxidative profile. Prenatal male Wistar rats were divided in control group and prediabetes (PrDM) group which received a streptozotocin injection. After one month, PrDM rats were divided: half consumed water and half WTEA during two months. WTEA phytochemical profile was determined. Rats were then subjected to glucose tolerance and insulin resistance tests. Cardiac glycolytic and oxidative profiles were determined. Prediabetes decreased glucose transporters (GLUT1 and GLUT3) mRNA expression, lactate and acetate content and lactate dehydrogenase activity in cardiac tissue. Prediabetes also decreased heart antioxidant capacity, increasing lipid peroxidation and protein oxidation. WTEA consumption improved glucose tolerance and insulin sensitivity in prediabetic rats and increased cardiac acetate and alanine contents and protein oxidation levels. WTEA consumption ameliorated overall metabolic status of prediabetic rats and prevented most of heart-related deleterious effects evaluated.
Article
An accurate method for the determination of 19 amino acids in tea with HPLC-UV after precolumn derivatization using 9-fluorenylmethyloxycarbonyl chloride (FMOC-Cl) has been developed. The gradient consisted of 0.1 M sodium acetate buffer pH (5.8) containing 0.05% (v/v) triethylamine (A) and 80% acetonitrile-water (B). The separation was performed on a Kinetex C18 column at 40 degrees C and 262 nm detection wavelength. The developed method was validated showing an excellent linearity (R-2 > 0.999), high recovery rates (>91%) and low detection and quantification limits (LOD: 0.057-0.534 mu g/mL; LOQ: 0.235-1.849 mu g/mL). Free amino acids were determined in 86 tea samples and found to be the highest in white tea with an average of 25 mg/g and elevated contents of GABA and asparagine. An inverse relationship was observed between the degree of aeration (fermentation) and the content of amino acids, especially of arginine. In addition, two steeping time experiments were carried out and the extraction kinetics of individual amino acids was studied. The results obtained demonstrated the high extraction efficiency of theanine with about 50% of its total quantity after 2 min brewing time. Furthermore, a comparison with the proposed ISO method for theanine gave very similar results.
Article
The study investigates the antioxidant characteristics of various white teas steeped in either hot or room-temperature water in relation to grade of tea and brewing conditions. Antioxidant activity, chelating activity, total phenol (TPC), flavonoids (TFC), theaflavins and individual catechin content were examined. The results confirm that extraction of tea leaves carried out with water at room temperature leads to the formation of infusions particularly rich in compounds with antioxidant activity. In fact, for all the white teas studied, cold infusions had a higher content of phenols (4.77÷7.63 mmol/L Gallic Acid Equivalents GAE), flavonoids (1.47÷2.53 mmol/L Catechin Equivalents CE) and catechins (441.5÷1328.2 μg/mL) compared to hot infusions (1.43÷4.02 mmol/L GAE, 0.70÷1.13 mmol/L CE, 83.4÷534.8 μg/mL, respectively). The same trend was also observed for antioxidant activities examined using the ABTS assay (cold: 17.09÷34.23; hot: 5.26÷17.07 mmol/L Trolox Equivalents) and by monitoring the effects of the infusions on LDL oxidation (lag time, cold: 172.4÷271.2; hot: 88.4÷145.9 min). A general trend in antioxidant activity and in polyphenolic compound content can be delineated between Chinese teas, i.e. Bai Mu Dan ≥ Xue Ya ≥ White Lung Ching > Anji Needle Mao Feng > Yhin Zhen Bai Hao and between African teas, i.e. White Salima Peony > Thyolo Bsp > Bvumbwe Bsp. Concerning metal chelating activity, all the white teas displayed similar levels (0.3÷0.6 mmol/L EDTA Equivalents) with no significant differences between the hot and cold infusions (except Bvumbwe Bsp and Thyolo Bsp). This paper contains key information on the antioxidant properties, TPC, TFC, and individual catechin content of several white teas commercially available and the outcomes suggest that preparing tea infused in room temperature water for approximately 2 hours may constitute an alternative tea beverage potentially richer in healthful bioactive compounds compared to the more commonly consumed hot tea infusions.
Article
Free amino acids are closely related to the savory taste and beneficial effects of tea, and high-performance liquid chromatography (HPLC) is the most widespread analytical approach for simultaneous determination of free amino acids in tea. However, the reported HPLC methods have drawbacks such as long run times, low resolution, or poor efficiency. In this study, a special amino acid analysis column was used to separate and verify 21 amino acids including l-theanine, the predominant amino acid in tea. The mobile phases, including the sodium acetate and acetic acid concentration in buffer B, and the pH and concentration of sodium acetate in buffer A were optimized. The elution gradients were optimized using DryLab 2000 Plus software. In this way, an online o-phthaldialdehyde precolumn derivatization HPLC-fluorescence detection method was developed for simultaneous determination of 21 amino acids. Comparison to other HPLC methods for simultaneous determination of free amino acids in tea showed that our method is easy (automated derivatization), quick (30 min), inexpensive, and green (using a minimum of solution). It has good resolution (≥1.8) and high selectivity (interpark time ≥ 0.5 min). Free amino acids in six tea samples were analyzed. This work provides an HPLC method to simultaneously measure 21 amino acids in tea and potential in other food products.
Article
The leaves at different processing stages of a single tea cultivar in order to obtain white (WT), green (GT) and black tea (BT) samples, were analysed. The capacities of tea polyphenolics to influence the glucose and lipid metabolism in HepG2 cell lines were evaluated. WT appeared the most active in reducing the glucose and cholesterol uptake (+17.7% and +32.4% in the glucose and cholesterol cell medium concentration, respectively). Incubation with WT enhanced LDL receptor binding activity by 40% (+20% for GT and +0% for BT) and led to an increase in HDL cell medium concentration of 33.3% (+20% for GT and +0% for BT). Finally, WT revealed the best inhibition capacity against lipase activity, and triglyceride levels in the cell medium increased by 400% (+382.6% for GT and +191.3% for BT). The present study intended to contribute to the little knowledge about the potential health benefits of white tea in individuals affected by metabolic syndrome.
Article
Theanine is the main amino acid component in tea. It usually constitutes between 1 and 2% of the dry weight of the tea leaves. It is as prevalent in tea as all other free amino acids combined. Both enantiomers of theanine were found to have a similar sweet taste, with little or no aftertaste. It was found that black and half-green teas (except for Formosa Oolong) contained as much, or more, theanine as green teas. No correlation was found between the absolute concentration of theanine in tea and its enantiomeric composition. An inverse correlation was found between certain grades of tea (e.g., pekoe, Flowery Orange Pekoe, etc.) and the percent of d-theanine present. This could provide the basis for a reproducible, scientific method to grade and/or evaluate teas. Theanine slowly racemizes in aqueous solution. It also undergoes hydrolysis, particularly at basic pH values. By monitoring these processes, information may be gleaned on the production, storage, handling, and shipping of tea and tea products. Keywords: Racemization; beverage; d-amino acid; tea grades; cyclodextrin column; column switching
Article
Green tea contains a high percentage of polyphenols, which are potent antioxidant and antimicrobial agents. However, interactions between polyphenols and food components may decrease their potential benefits. The aim of the study was to evaluate whether the antioxidant and antimicrobial capacities of different Argentinean green tea varieties could be affected by whey proteins. The results showed some degree of masking in the antioxidant and antimicrobial activity of green tea infusions when whey proteins are present. The degree of inhibition of antioxidant activity in each variety did not depend on the polyphenol concentration, indicating the importance of the particular polyphenol composition of each variety. The CH 410 variety exhibited the best performance as antioxidant and antimicrobial, even in the presence of whey proteins. The antimicrobial effects in the presence of whey proteins correlated with the polyphenol content of the green tea infusions and increased with the reduction of whey protein concentration. The antimicrobial effectiveness was similar within a pH range from 4.0 to 7.0, allowing its application to a wide group of foods.
Article
The efficiencies of different solvents in the extraction of phenolics from bagged and loose leaves of white and green tea, after different extraction times, as well as the antioxidative capacity of the obtained extracts, were investigated. The developed HPLC method has the potential to separate and determinate 17 phenolics widely distributed in plants, but in investigated tea extracts only four catechins and traces of three flavonols and one flavone were separated and detected based on comparison with authentic standards. The extraction efficiency of phenolics depended strongly on the time of extraction and the solvents used. The extraction of catechins from green tea was significantly affected by the form (bagged or loose) of the tea, whereas this effect was shown not to be statistically significant for white tea. Green tea was a richer source of phenolics than was white tea. The extraction of phenolics from white tea by water could be accelerated by the addition of lemon juice. Aqueous ethanol (40%) was most effective in the prolonged extraction of catechins. The antioxidative capacity of the investigated tea extracts correlated with their phenolic content. Copyright © 2008 Elsevier Ltd. All rights reserved.
Article
Renal cell carcinoma (RCC) is one of the most lethal amongst the urologic malignancies, comprising three percent of all human neoplasms, and its incidence appears to be rising. RCC is refractory to both chemotherapy and radiotherapy. Therefore, the discovery of new strategies for therapeutic intervention remains a priority. Green tea (Camellia sinensis) and tea polyphenols have been proposed to exert protective effects against several types of cancer, based on preclinical and clinical trial data; however, the anticarcinogenic activity of green tea towards RCC is unknown. In this study, a targeted metabolite analysis on a green tea leaves methanolic extract was performed by HPLC/DAD and the antiproliferative activity of the extract was assayed using human renal cancer cell lines A-498 and 769-P. The total phenolic content was very high (31.8% of methanolic extract), and the main compounds were flavan-3-ols (94.3% of the total phenolic content), and especially (−)-epigallocatechin-3-gallate (35.9% of the total phenolic content). In addition, two methylxanthines – theophylline and caffeine – were also present in the extract, caffeine being the most abundant. Green tea extract strongly inhibited the growth of both RCC cell lines in a concentration-dependent manner, with IC50 values of 54 ± 10 and 129 ± 28 μg/ml for A-498 and 769-P cells, respectively. This is the first report showing that green tea is likely to be an effective anticancer agent for renal cell carcinoma.
Article
The three main categories of tea: green, black and oolong, result from different processing procedures. In recent years tea has attracted more and more attention because of reported health benefits, in particularly as an antioxidant, but also as an anticarcinogenic and antiarteriosclerotic agent. It is generally believed that flavonoids are mainly responsible for these actions. Tea is now consumed throughout the world not just as a popular beverage, but, because its extracts have been prepared in a variety of physical forms, for example, strong infusions, soft extracts and powders, it is now widely available in a range of food, beverage, and toiletry and cosmetic products.
Article
The use of many antimicrobial compounds in combination can achieve a good microbiological safety in food while decreasing the doses of each compound in the product. This is interesting in terms of consumer demand. In that context, combinations of five aromatic compounds (thymol, carvacrol, citral, eugenol, geraniol) and four acidic compounds (acetic acid, citric acid, lactic acid, pyropolyphosphoric acid) were investigated for their ability to inhibit the growth of Salmonella sv. Typhimurium. Many combinations of either acidic or aromatic compounds appear to be promising. Some antimicrobials, like citric acid or thymol, lead to a better amplification of inhibition than others, but no real synergistic effect has been demonstrated between compounds. Moreover, our results underline that it is important to take into account the cumulative effect of each compound when compounds are mixed.