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Zhi-Ke-Bao pills (ZKB), a traditional Chinese medicine preparation composed of 13 herbs, is generally used to treat cough caused by external wind cold, phlegm, etc in clinical applications, and it plays a core role in relieving cough caused by COVID-19 and influenza in China. Till now, the understanding of its chemical constituents was dramatically limited due to its chemical complexity, restricting its clinical application or development. In this work, a developed ultra-high performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC-Q/TOF MS) method, a targeted and non-targeted strategy and network pharmacology were used to comprehensively characterize the chemical compositions in ZKB and predict its mechanism against cough. A total of 164 compounds (148 targeted compounds and 16 non-targeted ones) were identified or tentatively characterized in ZKB, including 65 flavonoids, 25 alkaloids, 19 organic acids, 41 saponins, 9 coumarins, 2 phenylpropanoids, 2 anthraquinones, and 1 other types. Among them, 37 compounds were unambiguously identified by comparison to reference standards. Meanwhile, the fragmentation behaviors of five main chemical structure types were also summarized. 309 targets and two core signaling pathways of ZKB against cough were predicted by network pharmacology, including MAPK and PI3K-Akt signaling pathways. It was the first time to characterize the chemical compounds of ZKB and reveal its potential mechanism against cough, providing the material basis for further quality control or pharmacodynamic evaluation of ZKB.
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Tosse , Medicamentos de Ervas Chinesas , Farmacologia em Rede , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/análise , Cromatografia Líquida de Alta Pressão/métodos , Tosse/tratamento farmacológico , Humanos , Espectrometria de Massas/métodos , Medicina Tradicional Chinesa/métodos , Antitussígenos/farmacologia , Antitussígenos/química , Antitussígenos/análise , Tratamento Farmacológico da COVID-19 , Alcaloides/análise , Alcaloides/química , Alcaloides/farmacologiaRESUMO
The root of Aconitum carmichaelii Debx. (Fuzi) is an herbal medicine used in China that exerts significant efficacy in rescuing patients from severe diseases. A key toxic compound in Fuzi, aconitine (AC), could trigger unpredictable cardiotoxicities with high-individualization, thus hinders safe application of Fuzi. In this study we investigated the individual differences of AC-induced cardiotoxicities, the biomarkers and underlying mechanisms. Diversity Outbred (DO) mice were used as a genetically heterogeneous model for mimicking individualization clinically. The mice were orally administered AC (0.3, 0.6, 0.9 mg· kg-1 ·d-1) for 7 d. We found that AC-triggered cardiotoxicities in DO mice shared similar characteristics to those observed in clinic patients. Most importantly, significant individual differences were found in DO mice (variation coefficients: 34.08%-53.17%). RNA-sequencing in AC-tolerant and AC-sensitive mice revealed that hemoglobin subunit beta (HBB), a toxic-responsive protein in blood with 89% homology to human, was specifically enriched in AC-sensitive mice. Moreover, we found that HBB overexpression could significantly exacerbate AC-induced cardiotoxicity while HBB knockdown markedly attenuated cell death of cardiomyocytes. We revealed that AC could trigger hemolysis, and specifically bind to HBB in cell-free hemoglobin (cf-Hb), which could excessively promote NO scavenge and decrease cardioprotective S-nitrosylation. Meanwhile, AC bound to HBB enhanced the binding of HBB to ABHD5 and AMPK, which correspondingly decreased HDAC-NT generation and led to cardiomyocytes death. This study not only demonstrates HBB achievement a novel target of AC in blood, but provides the first clue for HBB as a novel biomarker in determining the individual differences of Fuzi-triggered cardiotoxicity.
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Proteínas Quinases Ativadas por AMP , Aconitina , Cardiotoxicidade , Histona Desacetilases , Animais , Camundongos , Cardiotoxicidade/metabolismo , Cardiotoxicidade/etiologia , Histona Desacetilases/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Masculino , Humanos , Aconitum/química , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Medicamentos de Ervas Chinesas/farmacologiaRESUMO
In this manuscript, a broadband transmitarray antenna (TA) using a metasurface-based element is presented for millimeter-wave communication applications. The metasurface-based TA element adopts a receiver-transmitter configuration: metasurfaces are applied as the receiver and transmitter, and slot-coupled differentially fed striplines are used as the phase compensation. The designed TA element achieves good transmission performance with a more than 360° transmission phase shift range and less than 1-dB transmission insertion loss within a wide frequency range. To verify the proposed TA, a prototype is fabricated based on the conventional printed circuit board (PCB) process, and a pyramid horn is designed as the source. The measured results show that the proposed TA with the differential feed network presents a 1-dB gain bandwidth of 26.2% from 23.5 to 30.5 GHz and a peak gain of 24.5 dBi. The designed TA is a promising alternative for millimeter-wave communications applications because of its high gain, broad bandwidth, low costs, and convenient integration with other circuits.
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Variations in the quality of brewing water profoundly impact tea flavor. This study systematically investigated the effects of four common water sources, including pure water (PW), mountain spring water (MSW), mineral water (MW) and natural water (NW) on the flavor of Tieguanyin tea infusion. Brewing with MW resulted in a flat taste and turbid aroma, mainly due to the low leaching of tea flavor components and complex interactions with mineral ions (mainly Ca2+, Mg2+). Tea infusions brewed with NW exhibited the highest relative contents of total volatile compounds, while those brewed with PW had the lowest. NW and MSW, with moderate mineralization, were conducive to improving the aroma quality of tea infusion and were more suitable for brewing both aroma types of Tieguanyin. These findings offer valuable insights into the effect of brewing water on the sensory and physicochemical properties of oolong teas.
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To improve the quality of osmanthus black tea, samples produced with different scenting methods were prepared. The sensory quality was assessed and the characteristic aromatic components were explored using solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry. According to the results, osmanthus black tea obtained by adding osmanthus scenting in the fermentation process had the strongest floral aroma. The major contributors to the aroma of osmanthus black tea were identified as ß-ionone, dihydro-ß-ionone, benzeneacetaldehyde, citral, geraniol, and linalool by calculating their relative odor activity values. An analysis of the causes revealed that the moisture content of tea dhool significantly affected the adsorption of fresh flower aroma by tea. The experimental results showed that osmanthus black tea produced using tea dhool containing 30% moisture content had the highest content of crucial aroma components, suggesting the tea dhool under this condition had the strongest adsorption capacity for osmanthus aroma.
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Camellia sinensis , Oleaceae , Compostos Orgânicos Voláteis , Chá/química , Odorantes/análise , Compostos Orgânicos Voláteis/análise , Camellia sinensis/químicaRESUMO
Introduction: Instant teas are particularly rich in tea polyphenols and caffeine and have great potential as food ingredients or additives to improve the quality of food and enhance their nutritional and commercial value. Methods: To determine the relationships between raw material, drying method, and sensory and other quality attributes, instant teas were prepared from three tea varieties, namely black, green and jasmine tea, using two drying methods, namely spray-drying (SD) and freeze-drying (FD). Results: Both the raw tea material and drying method influenced the quality of the finished instant teas. Black tea was quality stable under two drying, while green tea taste deteriorated much after SD. Jasmine tea must be produced from FD due to huge aroma deterioration after SD. FD produced instant tea with higher sensory quality, which was attributed to the lower processing temperature. Chemical compositional analysis and widely targeted metabolomics revealed that SD caused greater degradation of tea biochemical components. The flavonoids content changed markedly after drying, and metabolomics, combined with OPLS-DA, was able to differentiate the three varieties of tea. Instant tea preparations via SD often lost a large proportion of the original tea aroma compounds, but FD minimized the loss of floral and fruity aroma compounds. Changes in the tea flavonoids composition, especially during drying, contributed to the flavor development of instant tea. Discussion: These results will provide an practicle method for high-quality instant tea production through choosing proper raw tea material and lowering down drying temperature with non-thermal technologies like FD.
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OBJECTIVE: Although the current European Association of Urology(EAU) guideline recommends that patients with intermediate-risk non-muscle-invasive bladder cancer (NMIBC) should accept intravesical chemotherapy or Calmette-Guerin (BCG) for no more than one year after transurethral resection of bladder tumor(TURBT), there is no consensus on the optimal duration of chemotherapy. Hence, we explored the optimal duration of maintenance intravesical chemotherapy in patients with intermediate-risk NMIBC. SUBJECTS AND METHODS: This was a real-world single-center retrospective cohort study. In total 158 patients with pathologically confirmed intermediate-risk NMIBC were included, who were divided into 4 subgroups based on the number of instillations given. We used Cox regression analysis and survival analysis chart to explore the 3-yr recurrence outcomes of tumor.The optimal duration was determined by receive operating characteristic curve (ROC). RESULTS: The median follow-up was 5.2 years. Compared with instillation for 1-2 months, the Hazard Ratios(HR) values of instillation for less than 1 month, maintenance instillation for 3-6 months and > 6 months were 3.57ã1.57 and 0.22(95% CI 1.27-12.41;0.26-9.28;0.07-0.80, P = 0.03;0.62;0.02, respectively). We found a significant improvement in 3-yr relapse-free survival in intermediate-risk NMIBC patients who maintained intravesical instillation chemotherapy for longer than 6 months, and the best benefit was achieved with 10.5 months of maintenance chemotherapy by ROC. CONCLUSIONS: In our scheme, the optimal duration of intravesical instillation with pirrubicin is 10.5 months. This new understanding provides valuable experience for the precise medical treatment model of intermediate-risk NMIBC.
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Neoplasias não Músculo Invasivas da Bexiga , Neoplasias da Bexiga Urinária , Humanos , Administração Intravesical , Quimioterapia de Manutenção , Estudos Retrospectivos , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Neoplasias da Bexiga Urinária/patologia , Vacina BCG/uso terapêutico , Invasividade NeoplásicaRESUMO
The sensory quality of tea is influenced by water quality, with natural spring water (NSW) gaining much attention for its natural and healthy qualities. The effects of NSW on the sensory attributes, physicochemical composition, and antioxidant capacity of Chinese tea were investigated. Tea brewed with pure water was the most resistant to oxidation and darkening. NSW with low total dissolved solids (TDS) was most suitable for brewing unfermented or mildly fermented teas, improving their sensory quality. The simulated green tea infusion system was used to investigate further the dramatic darkening of tea infusions in NSW. Exposure of infusions to air promoted the degradation, epimerization, and oxidative polymerization of catechins, and further formed theabrownins which darkened the tea infusions. These findings enabled tea consumers to choose the most suitable NSW for brewing Chinese teas and illustrated the darkening mechanism of tea infusion in high pH/TDS water.
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Camellia sinensis , Catequina , Antioxidantes/química , Camellia sinensis/química , Catequina/química , Oxirredução , Chá/química , Nascentes Naturais/químicaRESUMO
(+) and (-)-Eugenilones A-K, 11 pairs of undescribed enantiomeric sesquiterpenoids, together with three undescribed biogenetically related members eugenilones L-N, were discovered from the fruits of Eugenia uniflora Linn. (Myrtaceae). Structurally, eugenilones A-D were four caged sesquiterpenoids featuring 9,10-dioxatricyclo [6.2.2.02,7]dodecane, 11-oxatricyclo [5.3.1.03,8]undecane, and tricyclo [4.4.0.02,8]decane cores, respectively. Eugenilones E-K were eudesmane-type sesquiterpenoids, while eugenilones L-N were epoxy germacrane-type sesquiterpenoids. Notably, eugenilones A-K were efficiently resolved by chiral HPLC to give 11 pairs of optically pure enantiomers. The structures and absolute configurations of eugenilones A-N were determined through spectroscopic analyses, X-ray crystallography, and ECD calculations. The putative biosynthetic pathways for these undescribed isolates were proposed. Moreover, eugenilones A and E exhibited significant anti-inflammatory effects by inhibiting LPS-stimulated NO overproduction in RAW264.7 cells (IC50 values of 4.89 ± 0.37 µM and 20.89 ± 1.49 µM, respectively) and TNF-α-induced NF-κB activation in HEK293 cells (IC50 values of 10.97 ± 1.03 µM and 28.63 ± 1.59 µM, respectively).
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Eugenia , Sesquiterpenos , Animais , Camundongos , Humanos , Frutas , Células HEK293 , Estrutura Molecular , Células RAW 264.7 , Sesquiterpenos/farmacologia , Sesquiterpenos/químicaRESUMO
Introduction: Tea is the main raw material for preparing tea wine. Methods: In this research, four types of tea wine were prepared using different categories of tea leaves, including green tea, oolong tea, black tea, and dark tea, and the comparative study looking their physicochemical, sensorial, and antioxidant profiles were carried out. Results: The dynamic changes of total soluble solids, amino acids and ethanol concentrations, and pH were similar in four tea wines. The green tea wine (GTW) showed the highest consumption of total soluble solids and amino acids, and produced the highest concentrations of alcohol, malic, succinic, and lactic acid among all tea wines. The analysis of volatile components indicated the number and concentration of esters and alcohols increased significantly after fermentation of tea wines. GTW presented the highest volatile concentration, while oolong tea wine (OTW) showed the highest number of volatile compounds. GTW had the highest total catechins concentration of 404 mg/L and the highest ABTS value (1.63 mmol TEAC/mL), while OTW showed the highest DPPH value (1.00 mmol TEAC/mL). Moreover, OTW showed the highest score of sensory properties. Discussion: Therefore, the types of tea leaves used in the tea wine production interfere in its bioactive composition, sensorial, and antioxidant properties.
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Living vegetation volume (LVV) can objectively and accurately reflect the urban greenery quality, and provide a reliable data foundation for the quantitative study aiming to reveal the mechanisms underlying urban greenery ecological functions. According to the characteristics of dispersion and small scale of unit affiliated green space, we proposed a LVV estimation scheme for such urban green space, which included data acquisition, processing, entity segmentation, classification, single tree canopy extraction, and LVV calculation. First, point cloud data was obtained with a backpack LiDAR system, and the ground point clouds were eliminated by a multi-scale algorithm. Second, the Density Based Spatial Clustering of Application with Noise (DBSCAN) algorithm was used to cluster the non-ground point clouds, and density feature-based competitive algorithm was used to re-segmented for the overlapping area to generate independent objects. Third, the PointNet++ network model was used to extracted plant point clouds. Then, the canopy point clouds were extracted using the similarity of principal direction between neighboring points and distribution density of branch and leaf points. Finally, the LVV of individual tree canopy was calculated by the convex hull method, and then the LVV of the accessory greenland was summed up. Taking a science and technology park as an example, its total LVV was 21034.95 m3, among which the number of mango trees was the highest, and the total LVV was the largest (4868.64 m3, accounting for 23.2%). The tree species with the largest LVV per plant was Terminalia neotaliala tree, with an average of 120.37 m3 per plant. The relative error between LVV of trees estimated by this scheme compared with traditional method and convex hull method was 10.7%-33.7% and 2.7%-16.0%, with average value of 20.9% and 8.7%, respectively. This scheme could make full use of the characteristics of the three-dimensional point cloud and use a convex polyhedron to simulate the original form of the tree crown, which was more consistent with the actual situation of trees. The measurement and estimation solution of the LVV provided new ideas for rapid and accurate estimation of urban LVV.
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Parques Recreativos , Árvores , Folhas de Planta , Plantas , AlgoritmosRESUMO
Tieguanyin oolong tea (TOT), a semi-oxidized tea originating from Anxi county in China, is categorized into jade TOT, medium-baked TOT, and deep-baked TOT, based on different baking processes. To study the effects of baking, chemical analysis, sensory evaluation, and bioactivity assessments of the three TOTs were conducted. The results indicated that the baking process promoted the formation of colored macromolecules (e.g., theabrownins), which affected the color of tea infusion. Free amino acids underwent the Maillard reaction and generated specific Maillard reaction products, such as 5-hydroxymethylfurfural and furfural, which modified the taste and aroma. Floral and fresh volatiles were remarkably reduced, while multiple new volatiles were produced, forming a typically baked aroma. The antioxidant activity and antibacterial activity were reduced after baking, which might be associated with the decrease of monomeric catechins. These results provide a scientific basis for understanding the changes caused by the baking process.
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Tieguanyin is one of the most consumed oolong teas because of its distinctive flavor. The brewing process is crucial for the flavor performance of traditional teas, thus the effects of brewing conditions, including water/tea ratio (R), brewing temperature (T), and time (S) on the sensory traits, chemical composition, and antioxidant activity of Tieguanyin tea infusion were investigated using quadratic orthogonal regression design. Results showed that R affected all the quality variables most, its reduction could lead to the promotion of tea infusion concentration, antioxidant activity, and taste intensity, which was favored by the tea consumers drinking tea almost daily (DTD) but unacceptable for those drinking tea hardly (DTH). Based on the optimization of brewing conditions in response surface methodology (RSM), we recommended several brewing schemes for diverse consume goals: R = 34 mL/g, T = 80 °C, S = 80 s for DTH; R = 39 mL/g, T = 100 °C, S = 127 s for DTO (the consumers drinking tea occasionally); R = 20 mL/g, T = 100 °C, S = 100 s for DTD; R = 26 mL/g, T = 100 °C and S = 127 s for the common consumers seeking for flavor and health benefits. These results would be helpful for tea consumers with multiple demands.
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Seven batches of raw tea leaves, processed by different methods (steaming, pan-frying) and from two different harvesting seasons (spring, autumn), were used to investigate the effect of baking treatment on changes in the composition and content of nonvolatile and volatile compounds. The results showed that baking had a greater impact on sensory and flavor quality, which chemically modified some of taste and aroma components. The aroma concentrations of steamed teas (4,168-10,706 µg/L) were significantly higher than those of pan-fried teas (959-2,608 µg/L), and the aroma concentrations of baked green teas (2,608-10,706 µg/L) were significantly higher than those of unbaked teas (959-4,213 µg/L). Based on VIP > 1 and ACI > 1, (E, E)-3,5-octadien-2-one, hexanal, ß-ionone, 5-methylfurfural, ß-cyclocitral, and linalool were identified as the main aroma compounds. Chemical changes resulting from Maillard reaction were greater during baking of steamed, than pan-fried green tea. These results help improve the quality of green tea with baking.
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Chá , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas , Odorantes/análise , Paladar , Compostos Orgânicos Voláteis/análiseRESUMO
Oral processing (OP), referring to the whole process of food digestion in human mouth, has a major influence on food flavor perception. This study focused on the compositional changes of the four green tea epicatechins (viz., EC, EGC, ECG, EGCG) during OP, based on targeted and nontargeted metabolomics. It was found that the four epicatechins were all extensively lost through transformation undergoing OP, among which EC was the most stable one, whereas EGCG the least. EGCG was further revealed to be susceptible to human oral cavity in the simulated OP in vitro. It could be converted physically by precipitating with mucin in saliva, and chemically through hydrolysis and dimerization, mediated mainly by the neutral pH condition. The OP of epicatechins also caused salivary composition changes possibly involving health benefits of green tea. These findings could raise awareness of the interactions between epicatechins, or any other food materials, with human mouth.
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Catequina , Chá , Antioxidantes , Catequina/análise , Humanos , Metabolômica , PaladarRESUMO
Phenolic acids are important taste components in green tea. The aim of this study was to analyze the taste characteristics of phenolic acids and their influence on the bitterness and astringency of green tea by sensory evaluation and chemical determination. The major tea phenolic acids and quercetin-3-O-rutinoside (Que-rut) were significantly positively correlated with the bitterness (r = 0.757, p < 0.01; r = 0.605, p < 0.05) and astringency (r = 0.870, p < 0.01; r = 0.576, p < 0.05) of green tea infusion. The phenolic acids have a sour and astringent taste, whereas Que-rut has a mild astringent taste. Phenolic acids and Que-rut can increase the bitterness of epigallocatechin gallate (EGCG). However, these components behaved differently for astringency on EGCG. Gallic acid (GA) enhances the astringency throughout all the concentrations in this study. While it seemed to be double effects of caffeic acid (CA), chlorogenic acid (CGA), and Que-rut on that, i.e., the inhibition at lower concentrations (CA: 0-0.2 mM; CGA: 0-0.2 mM; Que-rut: 0-0.05 mM) but enhancement at higher ones. The phenolic acids and Que-rut interacted synergistically with tea infusion and as their concentration increased, the synergistic enhancement of the bitterness and astringency of tea infusion increased. These findings help provide a theoretical basis for improving the taste of middle and green tea.
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Aroma deterioration is one of the biggest problems in processing tea beverages. The aroma of tea infusion deteriorates fast during heat sterilization and the presence of ferrous ion (Fe2+) aggravates it. The underlying mechanism remains unveiled. In this study, Fe2+ was verified to deteriorate the aroma quality of green tea infusion with heat treatment. Catechins were necessary for Fe2+-mediated aroma deterioration. By enhancing the degradation of catechins, Fe2+ dramatically increased the production of hydrogen peroxide (H2O2). Fe2+ and H2O2 together exacerbated the aroma of green tea infusion with heat treatment. GC-MS analysis revealed that the presence of Fe2+ enhanced the loss of green/grassy volatiles and promoted the formation of new volatiles with diversified aroma characteristics, resulting in a dull scent of green tea infusion. Our results revealed how Fe2+ induced aroma deterioration of green tea infusion with heat treatment and could help guide tea producers in attenuating the aroma deterioration of tea infusion during processing.
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Compostos Ferrosos/análise , Odorantes/análise , Chá/química , Catequina/química , Cátions Bivalentes/análise , Temperatura Alta , Ferro/análise , EsterilizaçãoRESUMO
Lung aging alters the intrinsic structure of the lung and pulmonary surfactant system and increases the mortality and morbidity due to respiratory diseases in elderly individuals. We hypothesized that lung aging results from an insufficiency of type II alveolar epithelial cells (AECIIs) in the lung tissue. Sirtuin 3 (SIRT3) is a member of the sirtuin family of proteins that promote longevity in many organisms. Increased SIRT3 expression has been linked to an extended life span in humans. Hence, we speculated that the overexpression of SIRT3 may help to ameliorate lung senescence and improve AECII function. AECIIs were isolated from young and old patients with pneumothorax caused by pulmonary bullae. The expression of SIRT3, manganese superoxide dismutase, and catalase, as well as cell function and senescence indicators of young and old AECIIs, was measured before and after SIRT3 overexpression. After SIRT3 overexpression, the aged state of old AECIIs improved, and antiapoptotic activity, proliferation, and secretion were dramatically enhanced. Surfactant protein C (SPC), which is secreted by AECIIs, reduces alveolar surface tension, repairs the alveolar structure, and regulates inflammation. SPC deficiency in patients is associated with increased inflammation and delayed repair. SIRT3 deacetylated forkhead box O3a, thereby protecting mitochondria from oxidative stress and improving cell function and the senescent state of old AECIIs. These findings provide a possible direction for aging-delaying therapies and interventions for diseases of the respiratory system.
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Sirtuína 3/metabolismo , Idoso , Células Epiteliais Alveolares , Antioxidantes/metabolismo , Mecanismos de Defesa , Humanos , Pulmão/metabolismo , Estresse Oxidativo , Sirtuína 3/genéticaRESUMO
Zijuan tea is a representative anthocyanin-rich tea cultivar in China. In this study, Zijuan tea was used to produce a novel kombucha beverage (ZTK). The physicochemical, sensory properties, and antioxidant activity of ZTK were compared with that of black tea kombucha (BTK) and green tea kombucha (GTK). Results indicated that after fermentation, the color of ZTK changed from yellowish-brown to salmon-pink, because its anthocyanins (4.5 mg/L) appeared red in acidic conditions. Meanwhile no significant changes of color were observed in BTK and GTK. The dynamic changes of pH, biomass, and concentrations of sugars, amino acids, and main organic acids were similar in three kombucha beverages, except catechins showing different trends. Moreover, ZTK showed the highest overall acceptability score, antioxidant activity, and concentration of volatiles among the three kombucha beverages. Therefore, Zijuan tea is suitable for the preparation of kombucha beverage with attractive color and health benefits.
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Antioxidantes , Camellia sinensis , Antocianinas , Antioxidantes/análise , Fermentação , CháRESUMO
The effects of brewing water on the sensory attributes and physicochemical properties of tea infusions made from Chinese teas were investigated. The tea infusions brewed in water with higher pH and total dissolved solids (TDS), generally had a darker color and lower overall sensory acceptability. Moreover, those infusions had less catechins, particularly galloylated-catechins, and lower antioxidant capacity. The teas with less fermentation contained more galloylated-catechins and had higher antioxidant capacity, but were much more susceptible to high mineral brewing water. Green tea was proved to be the most susceptible one, whereas dark tea the most stable one. Green tea infusions prepared with higher pH/TDS water were more rapidly oxidized, resulting in a darker color due to polymerization of catechins, when exposed to the air. These findings suggested that low mineral brewing water was better for Chinese tea, both from the sensory and health benefit perspectives.