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1.
ACS Appl Mater Interfaces ; 13(33): 39126-39134, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34383476

RESUMO

The usage of exogenous antioxidant materials to relieve oxidative stress offers an important strategy for the therapy of oxidative stress-induced injuries. However, the fabrication processes toward the antioxidant materials usually require the involvement of extra metal ions and organic agents, as well as sophisticated purification steps, which might cause tremendous environmental stress and induce unpredictable side effects in vivo. To address these issues, herein, we proposed a novel strategy to fabricate green nanoparticles for efficiently modulating oxidative stress, which was facilely prepared from tea polyphenol extracts (originated from green tea) via a green enzymatic polymerization-based chemistry method. The resulting nanoparticles possessed a uniform spherical morphology and good stability in water and biomedium and demonstrated excellent radical scavenging properties. These nanoparticle scavengers could effectively prevent intracellular oxidative damage, accelerate wound recovery, and protect the kidneys from reactive oxygen species damaging in the acute kidney injury model. We hope this work will inspire the further development of more types of green nanoparticles for antioxidant therapies via similar synthetic strategies using green biomass materials.


Assuntos
Injúria Renal Aguda/prevenção & controle , Antioxidantes/química , Nanopartículas/química , Estresse Oxidativo/efeitos dos fármacos , Polifenóis/química , Chá/química , Células 3T3 , Células A549 , Animais , Antioxidantes/farmacologia , Catecóis/química , Sobrevivência Celular/efeitos dos fármacos , Feminino , Sequestradores de Radicais Livres/metabolismo , Química Verde , Peroxidase do Rábano Silvestre/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Peróxido de Hidrogênio/química , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Nanomedicina Teranóstica , Cicatrização/efeitos dos fármacos
2.
Molecules ; 26(16)2021 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-34443390

RESUMO

Since severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is producing a large number of infections and deaths globally, the development of supportive and auxiliary treatments is attracting increasing attention. Here, we evaluated SARS-CoV-2-inactivation activity of the polyphenol-rich tea leaf extract TY-1 containing concentrated theaflavins and other virucidal catechins. The TY-1 was mixed with SARS-CoV-2 solution, and its virucidal activity was evaluated. To evaluate the inhibition activity of TY-1 in SARS-CoV-2 infection, TY-1 was co-added with SARS-CoV-2 into cell culture media. After 1 h of incubation, the cell culture medium was replaced, and the cells were further incubated in the absence of TY-1. The viral titers were then evaluated. To evaluate the impacts of TY-1 on viral proteins and genome, TY-1-treated SARS-CoV-2 structural proteins and viral RNA were analyzed using western blotting and real-time RT-PCR, respectively. TY-1 showed time- and concentration-dependent virucidal activity. TY-1 inhibited SARS-CoV-2 infection of cells. The results of western blotting and real-time RT-PCR suggested that TY-1 induced structural change in the S2 subunit of the S protein and viral genome destruction, respectively. Our findings provided basic insights in vitro into the possible value of TY-1 as a virucidal agent, which could enhance the current SARS-CoV-2 control measures.


Assuntos
COVID-19/virologia , Polifenóis/farmacologia , SARS-CoV-2/efeitos dos fármacos , Chá/química , Animais , Antivirais/metabolismo , Antivirais/farmacologia , Biflavonoides/química , Biflavonoides/farmacologia , COVID-19/tratamento farmacológico , COVID-19/metabolismo , Camellia sinensis/metabolismo , Catequina/química , Catequina/farmacologia , Linhagem Celular , Chlorocebus aethiops , Genoma Viral/efeitos dos fármacos , Humanos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Polifenóis/isolamento & purificação , SARS-CoV-2/metabolismo , Células Vero , Carga Viral/efeitos dos fármacos
3.
Molecules ; 26(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34443624

RESUMO

Peptide synthesis is an area with a wide field of application, from biomedicine to nanotechnology, that offers the option of simultaneously synthesizing a large number of sequences for the purpose of preliminary screening, which is a powerful tool. Nevertheless, standard protocols generate large volumes of solvent waste. Here, we present a protocol for the multiple Fmoc solid-phase peptide synthesis in tea bags, where reagent recycling steps are included. Fifty-two peptides with wide amino acid composition and seven to twenty amino acid residues in length were synthesized in less than three weeks. A clustering analysis was performed, grouping the peptides by physicochemical features. Although a relationship between the overall yield and the physicochemical features of the sequences was not established, the process showed good performance despite sequence diversity. The recycling system allowed to reduce N, N-dimethylformamide usage by 25-30% and reduce the deprotection reagent usage by 50%. This protocol has been optimized for the simultaneous synthesis of a large number of peptide sequences. Additionally, a reagent recycling system was included in the procedure, which turns the process into a framework of circular economy, without affecting the quality of the products obtained.


Assuntos
Reciclagem/economia , Técnicas de Síntese em Fase Sólida/economia , Técnicas de Síntese em Fase Sólida/métodos , Chá/química , Fenômenos Químicos , Análise por Conglomerados
4.
Molecules ; 26(16)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34443485

RESUMO

Epidemiological studies have demonstrated that the intake of green tea is effective in reducing the risk of dementia. The most important component of green tea is epigallocatechin gallate (EGCG). Both EGCG and epigallocatechin (EGC) have been suggested to cross the blood-brain barrier to reach the brain parenchyma, but EGCG has been found to be more effective than EGC in promoting neuronal differentiation. It has also been suggested that the products of EGCG decomposition by the intestinal microbiota promote the differentiation of nerve cells and that both EGCG and its degradation products act on nerve cells with a time lag. On the other hand, the free amino acids theanine and arginine contained in green tea have stress-reducing effects. While long-term stress accelerates the aging of the brain, theanine and arginine suppress the aging of the brain due to their anti-stress effect. Since this effect is counteracted by EGCG and caffeine, the ratios between these green tea components are important for the anti-stress action. In this review, we describe how green tea suppresses brain aging, through the activation of nerve cells by both EGCG and its degradation products, and the reductions in stress achieved by theanine and arginine.


Assuntos
Envelhecimento/metabolismo , Encéfalo/metabolismo , Chá/química , Envelhecimento/efeitos dos fármacos , Animais , Arginina/farmacologia , Encéfalo/efeitos dos fármacos , Catequina/química , Catequina/metabolismo , Catequina/farmacologia , Glutamatos/farmacologia , Humanos
5.
Molecules ; 26(12)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208050

RESUMO

Potential effects of tea and its constituents on SARS-CoV-2 infection were assessed in vitro. Infectivity of SARS-CoV-2 was decreased to 1/100 to undetectable levels after a treatment with black tea, green tea, roasted green tea, or oolong tea for 1 min. An addition of (-) epigallocatechin gallate (EGCG) significantly inactivated SARS-CoV-2, while the same concentration of theasinensin A (TSA) and galloylated theaflavins including theaflavin 3,3'-di-O-gallate (TFDG) had more remarkable anti-viral activities. EGCG, TSA, and TFDG at 1 mM, 40 µM, and 60 µM, respectively, which are comparable to the concentrations of these compounds in tea beverages, significantly reduced infectivity of the virus, viral RNA replication in cells, and secondary virus production from the cells. EGCG, TSA, and TFDG significantly inhibited interaction between recombinant ACE2 and RBD of S protein. These results suggest potential usefulness of tea in prevention of person-to-person transmission of the novel coronavirus.


Assuntos
Antivirais/farmacologia , Biflavonoides/química , Catequina/química , Ácido Gálico/análogos & derivados , SARS-CoV-2/fisiologia , Chá/química , Replicação Viral/efeitos dos fármacos , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Antivirais/química , Biflavonoides/farmacologia , COVID-19/patologia , COVID-19/virologia , Catequina/análogos & derivados , Catequina/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Ácido Gálico/química , Ácido Gálico/farmacologia , Humanos , Mapas de Interação de Proteínas/efeitos dos fármacos , SARS-CoV-2/isolamento & purificação , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Chá/metabolismo , Células Vero
6.
Molecules ; 26(11)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200163

RESUMO

Tea polysaccharides (TPSs) are one of the main bioactive constituents of tea with various biological activities such as hypoglycemic effect, antioxidant, antitumor, and immunomodulatory. The bioactivities of TPSs are directly associated with their structures such as chemical composition, molecular weight, glycosidic linkages, and conformation among others. To study the relationship between the structures of TPSs and their bioactivities, it is essential to elucidate the structure of TPSs, particularly the fine structures. Due to the vast variation nature of monosaccharide units and their connections, the structure of TPSs is extremely complex, which is also affected by several major factors including tea species, processing technologies of tea and isolation methods of TPSs. As a result of the complexity, there are few studies on their fine structures and chain conformation. In the present review, we aim to provide a detailed summary of the multiple factors influencing the characteristics of TPS chemical structures such as variations of tea species, degree of fermentation, and preparation methods among others as well as their applications. The main aspects of understanding the structural difference of TPSs and influencing factors are to assist the study of the structure and bioactivity relationship and ultimately, to control the production of the targeted TPSs with the most desired biological activity.


Assuntos
Polissacarídeos/química , Chá/química , Antioxidantes/química , Fermentação/fisiologia , Imunomodulação/efeitos dos fármacos , Monossacarídeos/química
7.
Molecules ; 26(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204244

RESUMO

Tea polyphenols (TPs) are the general compounds of natural polyhydroxyphenols extracted in tea. Although a large number of studies have shown that TPs have obvious neuroprotective and neuro repair effects, they are limited due to the low bioavailability in vivo. However, TPs can act indirectly on the central nervous system by affecting the "microflora-gut-brain axis", in which the microbiota and its composition represent a factor that determines brain health. Bidirectional communication between the intestinal microflora and the brain (microbe-gut-brain axis) occurs through a variety of pathways, including the vagus nerve, immune system, neuroendocrine pathways, and bacteria-derived metabolites. This axis has been shown to influence neurotransmission and behavior, which is usually associated with neuropsychiatric disorders. In this review, we discuss that TPs and their metabolites may provide benefits by restoring the imbalance of intestinal microbiota and that TPs are metabolized by intestinal flora, to provide a new idea for TPs to play a neuroprotective role by regulating intestinal flora.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Polifenóis/farmacologia , Chá/química , Humanos , Microbiota , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Polifenóis/metabolismo
8.
Molecules ; 26(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204433

RESUMO

Catechins are a part of the chemical family of flavonoids, a naturally occurring antioxidant, and a secondary metabolite in certain plants. Green tea catechins are well recognized for their essential anti-inflammatory, photo-protective, antioxidant, and chemo-preventive functions. Ultraviolet radiation is a principal cause of damage to the skin. Studies observed that regular intake of green tea catechins increased the minimal dose of radiation required to induce erythema. The objectives of this systematic review and meta-analysis are to determine the effectiveness of green tea catechins in cutaneous erythema and elucidate whether green tea catechin consumption protects against erythema (sunburn) inflammation. A comprehensive literature search was conducted to identify the relevant studies. Two researchers carried out independent screening, data extraction, and quality assessment according to the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). The pooled effect of green tea catechins on protection against erythema was assessed using approaches fixed-effects or random-effects model to quantify the effectiveness of green tea catechins in the erythema dose-response. Studies not be included in meta-analyses were summarized narratively. Six randomized controlled studies of enrolled studies regularly administrated green tea catechins orally for 6 to 12 weeks involving healthy volunteers comprising a total of 100 participants were included in the analysis. The results revealed green tea catechins have favorable protection against erythema inflammation even at increased minimal erythema dose (MED) of ultraviolet radiation. Meta-analysis results confirm oral supplementation of green tea catechins is highly effective at low-intensity ultraviolet radiation-induced erythema response (MED range; 1.25-1.30) compared to placebo, showing a significant pooling difference (p = 0.002) in erythema index (SMD: -0.35; 95% CI, -0.57 to -0.13; I2 = 4%, p = 0.40) in the random-effects model. The pro-inflammatory signaling pathways through oral supplementation with green tea catechins are an attractive strategy for photo-protection in healthy human subjects and could represent a complementary approach to topical sunscreens. Therefore, studies that involved green tea catechin in topical applications to human subjects were also evaluated separately, and their meta-analysis is presented as a reference. The evidence indicates that regular green tea catechin supplementation is associated with protection against UV-induced damage due to erythema inflammation.


Assuntos
Catequina/farmacologia , Eritema/tratamento farmacológico , Chá/química , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Catequina/química , Eritema/metabolismo , Eritema/prevenção & controle , Flavonoides/metabolismo , Flavonoides/farmacologia , Humanos , Inflamação/tratamento farmacológico , Pele/metabolismo , Protetores Solares/farmacologia , Chá/metabolismo , Raios Ultravioleta/efeitos adversos
9.
Molecules ; 26(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209485

RESUMO

(-)-Epigallocatechin-3-O-gallate (EGCG), the most abundant component of catechins in tea (Camellia sinensis (L.) O. Kuntze), plays a role against viruses through inhibiting virus invasiveness, restraining gene expression and replication. In this paper, the antiviral effects of EGCG on various viruses, including DNA virus, RNA virus, coronavirus, enterovirus and arbovirus, were reviewed. Meanwhile, the antiviral effects of the EGCG epi-isomer counterpart (+)-gallocatechin-3-O-gallate (GCG) were also discussed.


Assuntos
Antivirais/farmacologia , COVID-19/tratamento farmacológico , Catequina/análogos & derivados , Chá/química , Animais , Antivirais/uso terapêutico , Catequina/farmacologia , Catequina/uso terapêutico , Humanos , Internalização do Vírus/efeitos dos fármacos , Vírus/efeitos dos fármacos
10.
Molecules ; 26(12)2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34201178

RESUMO

The health benefits of green tea are associated with its high catechin content. In scientific studies, green tea is often prepared with deionized water. However, casual consumers will simply use their local tap water, which differs in alkalinity and mineral content depending on the region. To assess the effect of water hardness on catechin and caffeine content, green tea infusions were prepared with synthetic freshwater in five different hardness levels, a sodium bicarbonate solution, a mineral salt solution, and deionized water. HPLC analysis was performed with a superficially porous pentafluorophenyl column. As water hardness increased, total catechin yield decreased. This was mostly due to the autoxidation of epigallocatechin (EGC) and epigallocatechin gallate (EGCG). Epicatechin (EC), epicatechin gallate (ECG), and caffeine showed greater chemical stability. Autoxidation was promoted by alkaline conditions and resulted in the browning of the green tea infusions. High levels of alkaline sodium bicarbonate found in hard water can render some tap waters unsuitable for green tea preparation.


Assuntos
Cafeína/química , Catequina/química , Chá/química , Água/química , Camellia sinensis/química , Catequina/análogos & derivados , Cromatografia Líquida de Alta Pressão/métodos , Dureza , Minerais/química , Extratos Vegetais/química
11.
Molecules ; 26(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202230

RESUMO

Prediabetes (PrDM) is a prodromal stage of diabetes mellitus (DM) with an increasing prevalence worldwide. During DM progression, individuals gradually develop complications in various organs. However, lungs are suggested to be affected later than other organs, such as the eyes, heart or brain. In this work, we studied the effects of PrDM on male Wistar rats' lungs and whether the regular consumption of white tea (WTEA) for 2 months contributes to the improvement of the antioxidant profile of this tissue, namely through improved activity of the first line defense antioxidant enzymes, the total antioxidant capacity and the damages caused in proteins, lipids and histone H2A. Our data shows that PrDM induced a decrease in lung superoxide dismutase and glutathione peroxidase activities and histone H2A levels and an increase in protein nitration and lipid peroxidation. Remarkably, the regular WTEA intake improved lung antioxidant enzymes activity and total antioxidant capacity and re-established the values of protein nitration, lipid peroxidation and histone H2A. Overall, this is the first time that lung is reported as a major target for PrDM. Moreover, it is also the first report showing that WTEA possesses relevant chemical properties against PrDM-induced lung dysfunction.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Pulmão/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Estado Pré-Diabético/metabolismo , Chá/química , Animais , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Glutationa Peroxidase/metabolismo , Histonas/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Extratos Vegetais/química , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo
12.
Molecules ; 26(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202382

RESUMO

Antioxidant polyphenols in black tea residue are an underused source of bioactive compounds. Microencapsulation can turn them into a valuable functional ingredient for different food applications. This study investigated the potential of using spent black tea extract (SBT) as an active ingredient in food packaging. Free or microencapsulated forms of SBT, using a pectin-sodium caseinate mixture as a wall material, were incorporated in a cassava starch matrix and films developed by casting. The effect of incorporating SBT at different polyphenol contents (0.17% and 0.34%) on the structural, physical, and antioxidant properties of the films, the migration of active compounds into different food simulants and their performance at preventing lipid oxidation were evaluated. The results showed that adding free SBT modified the film structure by forming hydrogen bonds with starch, creating a less elastic film with antioxidant activity (173 and 587 µg(GAE)/g film). Incorporating microencapsulated SBT improved the mechanical properties of active films and preserved their antioxidant activity (276 and 627 µg(GAE)/g film). Encapsulates significantly enhanced the release of antioxidant polyphenols into both aqueous and fatty food simulants. Both types of active film exhibited better barrier properties against UV light and water vapour than the control starch film and delayed lipid oxidation up to 35 d. This study revealed that starch film incorporating microencapsulated SBT can be used as a functional food packaging to protect fatty foods from oxidation.


Assuntos
Membranas Artificiais , Extratos Vegetais/química , Amido/química , Chá/química
13.
Molecules ; 26(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209247

RESUMO

Influenza is one of the most serious respiratory viral infections worldwide. Although several studies have reported that green tea catechins (GTCs) might prevent influenza virus infection, this remains controversial. We performed a systematic review and meta-analysis of eight studies with 5,048 participants that examined the effect of GTC administration on influenza prevention. In a random-effects meta-analysis of five RCTs, 884 participants treated with GTCs showed statistically significant effects on the prevention of influenza infection compared to the control group (risk ratio (RR) 0.67, 95%CIs 0.51-0.89, P = 0.005) without evidence of heterogeneity (I2= 0%, P = 0.629). Similarly, in three cohort studies with 2,223 participants treated with GTCs, there were also statistically significant effects (RR 0.52, 95%CIs 0.35-0.77, P = 0.001) with very low evidence of heterogeneity (I2 = 3%, P = 0.358). Additionally, the overall effect in the subgroup analysis of gargling and orally ingested items (taking capsules and drinking) showed a pooled RR of 0.62 (95% CIs 0.49-0.77, P = 0.003) without heterogeneity (I2= 0%, P = 0.554). There were no obvious publication biases (Egger's test (P = 0.138) and Begg's test (P = 0.103)). Our analysis suggests that green tea consumption is effective in the prophylaxis of influenza infections. To confirm the findings before implementation, longitudinal clinical trials with specific doses of green tea consumption are warranted.


Assuntos
Antivirais/uso terapêutico , Catequina/uso terapêutico , Extratos Vegetais/química , Chá/química , Antivirais/química , Catequina/química , Ensaios Clínicos como Assunto , Humanos , Influenza Humana
14.
Se Pu ; 39(4): 349-356, 2021 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-34227754

RESUMO

Pyrethroids (PYs) have been widely used to control pests and prevent diseases in tea gardens. However, with the increasingly stringent pesticide testing standards in the import and export trade of tea, there is an urgent need for methods to detect trace amounts of PYs in tea. In this study, a covalent organic framework (COF) material TpBD with excellent thermal/chemical stability, high porosity, and a large specific surface area was prepared by a room-temperature solution-suspension approach (SSA). TpBD-coated solid phase microextraction (SPME) fibers were fabricated by coating the material on etched stainless-steel fibers by a simple physical coating method. The fibers were used in combination with gas chromatography-tandem mass spectrometry (GC-MS/MS) to establish a highly sensitive method for the detection of PYs. The enrichment factors of this method for cyfluthrin, cypermethrin, flucythrinate, fenvalerate, and deltamethrin were 702-2687. The method showed low LODs (0.1-0.5 ng/L), wide linear ranges (0.2-800 ng/L), good linearities (correlation coefficients (R)≥0.9991) and acceptable repeatabilities (RSD≤11.0%, n=3). Green tea and oolong tea samples were analyzed using the developed method, and trace levels of the five PYs were successfully detected. The recoveries of the spiked PYs in the real green tea and oolong tea samples were in the range of 80.2%-109.5%. Experimental results showed that the established analytical method is suitable for the determination of PY pesticides in tea. Furthermore, the TpBD material was successfully prepared by the SSA method, demonstrating that the method has good universality and excellent potential for the simple synthesis of other COF materials.


Assuntos
Estruturas Metalorgânicas , Piretrinas , Chá/química , Cromatografia Gasosa-Espectrometria de Massas , Piretrinas/análise , Microextração em Fase Sólida , Espectrometria de Massas em Tandem , Temperatura
15.
Molecules ; 26(13)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206736

RESUMO

Green tea can influence the gut microbiota by either stimulating the growth of specific species or by hindering the development of detrimental ones. At the same time, gut bacteria can metabolize green tea compounds and produce smaller bioactive molecules. Accordingly, green tea benefits could be due to beneficial bacteria or to microbial bioactive metabolites. Therefore, the gut microbiota is likely to act as middle man for, at least, some of the green tea benefits on health. Many health promoting effects of green tea seems to be related to the inter-relation between green tea and gut microbiota. Green tea has proven to be able to correct the microbial dysbiosis that appears during several conditions such as obesity or cancer. On the other hand, tea compounds influence the growth of bacterial species involved in inflammatory processes such as the release of LPS or the modulation of IL production; thus, influencing the development of different chronic diseases. There are many studies trying to link either green tea or green tea phenolic compounds to health benefits via gut microbiota. In this review, we tried to summarize the most recent research in the area.


Assuntos
Bactérias/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Chá , Animais , Antioxidantes/farmacologia , Catequina/farmacologia , Disbiose/complicações , Disbiose/tratamento farmacológico , Humanos , Inflamação/metabolismo , Neoplasias/complicações , Neoplasias/metabolismo , Obesidade/complicações , Obesidade/metabolismo , Fenóis/química , Fenóis/metabolismo , Polifenóis/farmacologia , Chá/química
16.
Molecules ; 26(12)2021 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-34199199

RESUMO

Natural products have always enjoyed great popularity among consumers. Wild tea is an interesting alternative to tea from intensive plantations. The term "wild tea" is applied to many different varieties of tea, the most desirable and valued of which are native or indigenous tea plants. Special pro-health properties of wild tea are attributed to the natural conditions in which it grows. However, there are no complex studies that describe quality and health indicators of wild tea. The aim of this research was to evaluate the quality of wild and cultivated green tea from different regions of China: Wuzhishan, Baisha, Kunlushan, and Pu'Er. The assessment was carried out by verifying the concentration of selected chemical components in tea and relating it to the health risks they may pose, as well as to the nutritional requirements of adults. Wild tea was characterized by higher micronutrient concentration. The analyzed teas can constitute a valuable source of Mn in the diet. A higher concentration of nitrates and oxalates in cultivated tea can be associated with fertilizer use. The analyzed cultivated tea was a better source of antioxidants with a higher concentration of caffeine. There were no indications of health risks for wild or cultivated teas.


Assuntos
Antioxidantes/análise , Fertilizantes/análise , Oxalatos/análise , Extratos Vegetais/análise , Folhas de Planta/química , Polifenóis/química , Chá/química , China , Elementos Químicos , Humanos , Nitratos/análise , Controle de Qualidade
17.
Molecules ; 26(12)2021 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-34203004

RESUMO

Green tea and its bioactive components, especially polyphenols, possess many health-promoting and disease-preventing benefits, especially anti-inflammatory, antioxidant, anticancer, and metabolic modulation effects with multi-target modes of action. However, the effect of tea polyphenols on immune function has not been well studied. Moreover, the underlying cellular and molecular mechanisms mediating immunoregulation are not well understood. This review summarizes the recent studies on the immune-potentiating effects and corresponding mechanisms of tea polyphenols, especially the main components of (-)-epigallocatechin-3-gallate (EGCG) and (-)-epicatechin-3-gallate (ECG). In addition, the benefits towards immune-related diseases, such as autoimmune diseases, cutaneous-related immune diseases, and obesity-related immune diseases, have been discussed.


Assuntos
Antioxidantes/farmacologia , Imunidade/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Polifenóis/farmacologia , Chá/química , Animais , Antioxidantes/química , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Catequina/análogos & derivados , Catequina/química , Catequina/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Humanos , Fatores Imunológicos/química , Polifenóis/química
18.
Int J Mol Sci ; 22(10)2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-34064673

RESUMO

Histone methylation plays an important regulatory role in the drought response of many plants, but its regulatory mechanism in the drought response of the tea plant remains poorly understood. Here, drought stress was shown to induce lower relative water content and significantly downregulate the methylations of histone H3K4 in the tea plant. Based on our previous analysis of the SET Domain Group (SDG) gene family, the full-length coding sequence (CDS) of CsSDG36 was cloned from the tea cultivar 'Fuding Dabaicha'. Bioinformatics analysis showed that the open reading frame (ORF) of the CsSDG36 gene was 3138 bp, encoding 1045 amino acids and containing the conserved structural domains of PWWP, PHD, SET and PostSET. The CsSDG36 protein showed a close relationship to AtATX4 of the TRX subfamily, with a molecular weight of 118,249.89 Da, and a theoretical isoelectric point of 8.87, belonging to a hydrophilic protein without a transmembrane domain, probably located on the nucleus. The expression of CsSDG36 was not detected in the wild type, while it was clearly detected in the over-expression lines of Arabidopsis. Compared with the wild type, the over-expression lines exhibited lower hyperosmotic resistance by accelerating plant water loss, increasing reactive oxygen species (ROS) pressure, and increasing leaf stomatal density. RNA-seq analysis suggested that the CsSDG36 overexpression caused the differential expression of genes related to chromatin assembly, microtubule assembly, and leaf stomatal development pathways. qRT-PCR analysis revealed the significant down-regulation of stomatal development-related genes (BASL, SBT1.2(SDD1), EPF2, TCX3, CHAL, TMM, SPCH, ERL1, and EPFL9) in the overexpression lines. This study provides a novel sight on the function of histone methyltransferase CsSDG36 under drought stress.


Assuntos
Arabidopsis/fisiologia , Histona-Lisina N-Metiltransferase/metabolismo , Pressão Osmótica , Proteínas de Plantas/metabolismo , Estresse Fisiológico , Chá/enzimologia , Regulação da Expressão Gênica de Plantas , Histona-Lisina N-Metiltransferase/genética , Proteínas de Plantas/genética , Chá/química
19.
Food Chem ; 362: 130257, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34118510

RESUMO

The sensory features of white peony teas (WPTs) significantly change with storage age; however, their comprehensive associations with composition are still unclear. This study aimed to clarify the sensory quality-related chemical changes in WPTs during storage. Liquid chromatography-tandem mass spectrometry based on widely targeted metabolomics analysis was performed on WPTs of 1-13 years storage ages. Weighted gene co-expression network analysis (WGCNA) was used to correlate metabolites with sensory traits including color difference values and taste attributes. 323 sensory trait-related metabolites were obtained from six key modules via WGCNA, verified by multiple factor analysis. The decline and transformation of abundant flavonoids, tannins and amino acids were related to the reduced astringency, umami and increased browning of tea infusions. In contrast, the total contents of phenolic acids and organic acids increased with storage. This study provides a high-throughput method for the association of chemical compounds with various sensory traits of foods.


Assuntos
Metabolômica , Paeonia/química , Paladar , Chá/química , Aminoácidos/análise , Adstringentes/análise , Cromatografia Líquida , Flavonoides/análise , Manipulação de Alimentos/normas , Hidroxibenzoatos/análise , Espectrometria de Massas , Tempo
20.
Nutrients ; 13(5)2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-34067795

RESUMO

Matcha, a type of green tea, has a higher amino acid content than other types of tea. We previously examined the ability of matcha to improve cognitive function in older adults and determined that continuous matcha intake improves attention and executive function. This study aimed to compare the effects of matcha and caffeine and clarify the differences between these effects. The study was registered at the University Hospital Medical Information Network (UMIN000036578). The effect of single and continuous intake was compared, and the usefulness of continuous intake was evaluated under the stress condition. The Uchida-Kraepelin test (UKT) was used to induce mild acute stress, and the Cognitrax was used to evaluate cognitive function. A single dose of caffeine improved attentional function during or after stress loading. The reduced reaction time in the Cognitrax, observed following a single dose of matcha, was likely due to caffeine. The matcha group showed an increase in the amount of work after continuous intake, whereas the caffeine group only showed an increase in the amount of work for the UKT after a single dose. Ingesting matcha with caffeine improves both attention and work performance when suffering from psychological stress compared with caffeine alone.


Assuntos
Cafeína/administração & dosagem , Cognição/efeitos dos fármacos , Ingestão de Alimentos/psicologia , Estresse Psicológico/psicologia , Chá , Idoso , Atenção/efeitos dos fármacos , Método Duplo-Cego , Ingestão de Líquidos , Função Executiva/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Chá/química
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