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1.
Food Chem X ; 21: 101190, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38357378

RESUMO

The present study comprehensively used integrated multi-spectral omics combined with sensory evaluation analysis to investigate the quality of three types of Yunnan Congou black teas from different tree ages (decades, DB; hundreds, HB; a thousand years, TB). TB infusion presented the highest scores of sweetness and umami, higher brightness, and yellow hue. Eighty-four marker metabolites were identified, including Amadori rearrangement products, catechin oxidation products, flavonoid glycosides, and organic acids, which are simultaneously related to tea infusions' color and taste. Moreover, the content of some characteristic flavonoid glycosides and organic acids was determined. Our finding implied trans-4-O-p-coumaroylquinic acid and quercetin 3-O-rutinoside contributed to bitterness and astringency, while dehydro theanine-glucose Amadori product and xylopyranosyl-glucopyranose resulted in umami and sweetness. These results provided quantitative and qualitative information for deciphering differences among black teas with different tea plant ages, conducing to the further utilization of ancient tea plants in Southwest China.

2.
Food Chem ; 446: 138827, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38402772

RESUMO

As the final processing step, drying temperature between 90 and 140 â„ƒ is usually applied to terminate enzymatic activities and improve sensory characteristics of black tea. Liquid chromatography tandem mass spectrometry (LC-MS) based non-targeted and targeted metabolomics analyses combined in vitro biological assays were adopted to investigate the chemical and biological variations after drying. Fifty-nine differentially expressed metabolites including several hydroxycinnamic acid derivatives and pyroglutamic acid-glucose Amadori rearrangement products (ARPs) were identified, the latter of which was correspondingly accumulated with increasing temperature. The levels of theaflavins (TFs), thearubigins (TRs), monosaccharides and free amino acids gradually decreased with increasing temperature. Furthermore, the bioassays of black tea showed that drying under 110 â„ƒ provided the highest antioxidant capacities, but the inhibitory effects on α-glucosidase and α-amylase were decreasing along with increasing drying temperature. These results are valuable for optimizing drying process to obtain superior sensory properties and preserve bioactivities of black tea.


Assuntos
Camellia sinensis , Chá , Chá/química , Polifenóis/análise , Temperatura , Camellia sinensis/química , Cromatografia Líquida , Antioxidantes/análise
3.
J Agric Food Chem ; 72(8): 4384-4392, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38354408

RESUMO

The linoleic acid reaction models were set at 150 °C for 120 min, and its oxidation process was monitored by nuclear magnetic resonance (NMR) and gas chromatography-mass spectrometry (GC-MS). Results showed that no furan was formed from linoleic acid without heating, while furan accumulated throughout the heating process. Linoleic acid ran out within 30 min, which indicated that furan was formed mainly from the intermediate oxidation products of linoleic acid after 30 min. It should be noticed that the content of (E,E)-2,4-decadienal reached maximum once the linoleic acid ran out and then decreased with the formation of furan. Multivariate statistical analysis suggested that (E,E)-2,4-decadienal was the most important aldehyde related to furan formation during linoleic acid oxidation. To prove this assumption, the variation of furan from (E,E)-2,4-decadienal reaction models heating at 150 °C for 60 min was also studied. Results showed that the content of furan increased with the oxidation of (E,E)-2,4-decadienal. Furthermore, NMR and GC-MS data proved that (E,E)-2,4-decadienal could be oxidized to 4,5-epoxy-(E)-2-decenal. In conclusion, our results supported (E,E)-2,4-decadienal and trans-4,5-epoxy-(E)-2-decenal as critical intermediate products of furan formation from linoleic acid oxidation.


Assuntos
Aldeídos , Alcenos , Temperatura Alta , Ácido Linoleico , Ácido Linoleico/química , Oxirredução , Furanos/química
4.
Clin Rheumatol ; 40(6): 2427-2438, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33389313

RESUMO

OBJECTIVE: This study aimed to investigate the efficacy and safety of Tripterygium wilfordii Hook F. (TwHF) in the treatment of osteoarticular lesions in synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome. METHODS: Eligible SAPHO patients were recruited to this single-center trial to receive 12-week TwHF treatment. Two dose groups (1.0-mg/kg/day group and 1.5-mg/kg/day group) were designed and patients were allocated (1:1) to these two groups. The primary endpoint was the change from baseline in Ankylosing Spondylitis Disease Activity Score on the basis of C-reactive protein level (ASDAS) at week 12. RESULTS: All the 30 included patients completed the trial. At week 12, both dose groups showed significant change from baseline in ASDAS (1.0-mg/kg/day group: - 1.34 (1.10), p = 0.000; 1.5-mg/kg/day group: - 1.53 (1.19), p = 0.000). Similar improvement was also found in the Visual Analogue Scale in global osteoarticular pain, Bath Ankylosing Spondylitis Disease Activity Index, and other efficacy measures. The results showed a fast-acting characteristic of TwHF that the maximum efficacy was achieved within the first 2-4 weeks and maintained at a stable level for the rest of the study. No significant differences were observed between the two dose groups under the current sample size. TwHF was well tolerated that no severe adverse events or irregular menstruation were recorded, except for one patient who developed severe alanine aminotransferase elevation at the last follow-up and has stopped the TwHF treatment after the 12-week follow-up. CONCLUSIONS: TwHF should be considered for the treatment of osteoarticular lesions in SAPHO syndrome in clinical practice because of significant efficacy, reliable safety, and high socioeconomic value. TRIAL REGISTRATION: ChiCTR1900025912 Key points • This is the first clinical trial to evaluate Tripterygium wilfordii Hook F. (TwHF) in the treatment of synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome. • Twelve-week TwHF treatment in both dose groups designed (1.0-mg/kg/day group and 1.5-mg/kg/day group) was well tolerated and could lead to significant disease remission of SAPHO syndrome. • No significant differences were observed between the two dose groups under the current sample size. • TwHF should be considered for the treatment of osteoarticular lesions in SAPHO syndrome in clinical practice because of significant efficacy, reliable safety, and high socioeconomic value.


Assuntos
Acne Vulgar , Síndrome de Hiperostose Adquirida , Hiperostose , Osteíte , Sinovite , Acne Vulgar/tratamento farmacológico , Síndrome de Hiperostose Adquirida/tratamento farmacológico , Feminino , Humanos , Hiperostose/tratamento farmacológico , Osteíte/tratamento farmacológico , Tripterygium
6.
Front Oncol ; 10: 593578, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33330081

RESUMO

INTRODUCTION: Glioblastoma multiforme (GBM) is the most common primary central nervous (CNS) system malignancy with a poor prognosis. The standard treatment for GBM is neurosurgical resection, followed by radiochemotherapy and adjuvant temozolomide chemotherapy. Predictive biomarkers, such as methylation of the promoter region of the O6-methylguanine DNA methyltransferase (MGMT) gene, can successfully distinguish subgroups with different prognosis after temozolomide chemotherapy. Based on multiomics studies, epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF), BRAF V600E mutation, neurotrophic tyrosine receptor kinase (NTRK) fusions and other potential therapy targets have been found. METHODS: We have reviewed the preclinical and clinical evidence for NTRK fusions and TRK inhibitors therapy in cancers with NTRK fusions in pan-cancer and gliomas. RESULTS: Several NTRK1/2/3 fusions have been reported in GBM and preclinical studies have proven that NTRK fusions are potential driver mutations in some high-grade gliomas. Tropomyosin receptor kinase (TRK) inhibitors have shown efficacy as targeted therapies for extracranial tumors with NTRK fusions in recent clinical trials, with potential CNS tolerability and activity. However, whether NTRK gene fusions can affect survival status, the efficacy and resistance of TRK inhibitors in GBMs are lacking high-level evidences. CONCLUSIONS: For GBM patients, NTRK fusions and TRK inhibitors are potential target therapy strategy but remain biological mechanism and clinical significance unclarified. More clinical data and future clinical trials are needed to provide more evidence that supports targeted therapy for GBM with NTRK fusions.

7.
Food Chem ; 311: 125895, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31780220

RESUMO

Pile-fermentation is the most important process of producing ripened pu-erh tea. To study the chemical changes of tea leaves during pile-fermentation (PF), liquid chromatography coupled with tandem mass spectrometry (LC-MS) was used. Untargeted metabolomics analysis revealed that the first stage of PF is crucial in transforming the original secondary metabolites, whereas the contents of flavan-3-ols and gallic acid were decreased after long-term PF. Targeted metabolomics analysis indicated that the levels of puerins (N-ethyl-2-pyrrolidinone substituted gallocatechin and catechin) were significant increased after the first stage of PF, but after long-term PF the levels of flavonol glycosides, procyanidins and galloylated flavan-3-ols were significantly decreased. Accordingly, long-term PF also decreased the inhibition of α-amylase and α-glucosidase activities of the extracts. As a conclusion, pile-fermentation is an important step of changing the polyphenols and bioactivities of pu-erh tea.


Assuntos
Camellia/metabolismo , Metabolômica , Amilases/antagonistas & inibidores , Amilases/metabolismo , Camellia/química , Análise por Conglomerados , Fermentação , Flavonóis/metabolismo , Ácido Gálico/metabolismo , Glicosídeos/metabolismo , Análise dos Mínimos Quadrados , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Análise de Componente Principal , Proantocianidinas/metabolismo
8.
J Agric Food Chem ; 67(19): 5306-5317, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30892882

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is a typical chronic liver disease highly correlated with metabolic syndrome. Growing prevalence of NAFLD is supposed to be linked with the unhealthy lifestyle, especially high-calorie diet and lacking enough exercise. Currently, there is no validated pharmacological therapy for NAFLD except for weight reduction. However, many dietary strategies had preventive effects on the development of liver steatosis or its progression. As one of the most common beverages, green tea contains abundant bioactive compounds possessing antioxidant, lipid-lowering, and anti-inflammatory effects, as well as improving insulin resistance and gut dysbiosis that can alleviate the risk of NAFLD. Hence, in this review, we summarized the studies of green tea and its components on NAFLD from animal experiments and human interventions and discussed the potential mechanisms. Available evidence suggested that tea consumption is promising to prevent NAFLD, and further mechanisms and clinical studies need to be investigated.


Assuntos
Camellia sinensis/metabolismo , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Chá/metabolismo , Animais , Antioxidantes/química , Antioxidantes/metabolismo , Camellia sinensis/química , Humanos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Chá/química
9.
Food Res Int ; 116: 731-736, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30717002

RESUMO

ß-Carotene (BC) serves as an important source of provitamin A and natural edible pigment, but the application is limited because of its instability and low oral-bioavailability. A tea polyphenols-ß-carotene (TP-BC) oil-in-water (O/W) nanoemulsion was prepared with the core oil phase containing BC and the water phase containing TP. During storage at three different temperatures (4, 25 and 35 °C), the TP-BC nanoemulsion had a better stability and higher retention rate of BC than BC nanoemulsion. An in vitro simulated digestion assay indicated that the BC recovery rates of TP-BC nanoemulsion at digestion phases I and II were significantly increased compared to the BC nanoemulsion. An in vivo absorption study showed that TP-BC nanoemulsion had higher conversion efficiency on vitamin A compared to the BC nanoemulsion. These results suggested that tea polyphenols are effective ingredients for improving the oral-bioavailability of BC.


Assuntos
Camellia sinensis/química , Suplementos Nutricionais , Portadores de Fármacos , Absorção Intestinal/efeitos dos fármacos , Nanopartículas , Óleos/química , Polifenóis/farmacologia , Água/química , beta Caroteno/metabolismo , Administração Oral , Animais , Disponibilidade Biológica , Biotransformação , Digestão , Composição de Medicamentos , Estabilidade de Medicamentos , Emulsões , Masculino , Polifenóis/administração & dosagem , Polifenóis/isolamento & purificação , Ratos Sprague-Dawley , beta Caroteno/administração & dosagem , beta Caroteno/farmacocinética
10.
J Agric Food Chem ; 67(19): 5405-5412, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30485095

RESUMO

Large-leaf yellow tea (LYT) is made from mature tea leaves with stems and has unique sensory characteristics different from other teas. To study the chemical changes of LYT during processing, samples were collected from each step for quantitative and qualitative analyses by high-performance liquid chromatography and liquid chromatography-mass spectrometry (LC-MS). LC-MS-based nontargeted and targeted metabolomics analyses revealed that the tea sample after roasting was markedly different from samples before roasting, with the levels of epicatechins and free amino acids significantly decreased, but the epimerized catechins increased dramatically. After accounting for common compounds in tea, N-ethyl-2-pyrrolidinone-substituted flavan-3-ols were found to be the marker compounds responsible for the classification of all samples, as they rapidly rose with increasing processing temperature. These findings suggested that the predominant changes in the tea constituents during large-leaf yellow tea roasting were the thermally induced degradation and epimerization of catechins and the formation of N-ethyl-2-pyrrolidinone-substituted flavan-3-ols from l-theanine.


Assuntos
Camellia sinensis/química , Cromatografia Líquida de Alta Pressão/métodos , Metabolômica/métodos , Polifenóis/química , Espectrometria de Massas em Tandem/métodos , Biomarcadores/química , Cor , Culinária , Temperatura Alta , Folhas de Planta/química , Chá/química
11.
Food Funct ; 9(10): 5162-5168, 2018 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-30246823

RESUMO

Teas contain bioactive polyphenols, such as (-)-epigallocatechin gallate (EGCG), which is not stable during the processing of tea. EGCG can be epimerized into (-)-gallocatechin gallate (GCG), which is present in very small amounts in fresh tea leaves. An infusion made from roasted large-leaf yellow tea inhibited α-glucosidase more significantly than an infusion of unroasted yellow tea, with IC50 values of 76.08 ± 8.96 and 170.17 ± 33.00 µg mL-1, respectively. After roasting, the content of GCG showed about a 5-fold increase, while EGCG showed a decrease of 56.6%. Of the two main α-glucosidase inhibitors, GCG exhibited a higher inhibitory effect on α-glucosidase than its corresponding epimer (EGCG), whose IC50 value was about 3-fold lower. Modeling of molecular docking suggested that GCG preferably binds to the target α-glucosidase protein; this was confirmed by in vitro protein-polyphenol binding, where GCG had a binding rate about 4 times higher than that of EGCG. Comparative in vivo studies using oral starch tolerance tests in mice verified that GCG exhibited lower postprandial blood glucose compared to EGCG. These results suggest that roasting is a simple and effective way to increase the capacity of large-leaf yellow tea to regulate postprandial blood glucose.


Assuntos
Camellia sinensis/química , Catequina/química , Culinária/métodos , Diabetes Mellitus Tipo 2/dietoterapia , Inibidores de Glicosídeo Hidrolases/química , Hipoglicemiantes/química , Extratos Vegetais/química , alfa-Glucosidases/química , Animais , Glicemia/metabolismo , Camellia sinensis/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Hipoglicemiantes/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Extratos Vegetais/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Amido/metabolismo , Chá/química , Chá/metabolismo , alfa-Glucosidases/metabolismo
12.
Food Chem ; 246: 74-81, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29291881

RESUMO

Quantitative analysis and untargeted liquid chromatography mass spectrum (LC-MS) based metabolomics of different grades of Keemun black tea (KBT) were conducted. Quantitative analysis did not show tight correlation between tea grades and contents of polyphenols, but untargeted metabolomics analysis revealed that high-grades KBT were distinguished from the low-grades. S-plot and Variable Importance (VIP) analysis gave 28 marker compounds responsible for the discrimination of different grades of KBT. The inhibitory effects of KBT on α-amylase and α-glucosidase were positively correlated to tea grades, and the correlation coefficient between each marker compound and inhibitory rate were calculated. Thirteen compounds were positively related to the anti-glycemic activity, and theasinensin A, afzelechin gallate and kaempferol-glucoside were confirmed as grade-related bioactive marker compounds by chemical and bioassay in effective fractions. This study suggested that combinatory metabolomics and bioactivities assay provided a new strategy for the classification of tea grades.


Assuntos
Análise de Alimentos/métodos , Metabolômica/métodos , Chá/química , alfa-Amilases/antagonistas & inibidores , Benzopiranos/análise , Biomarcadores/análise , Cromatografia Líquida de Alta Pressão/métodos , Análise por Conglomerados , Flavonoides/análise , Inibidores de Glicosídeo Hidrolases/farmacologia , Hipoglicemiantes/farmacologia , Fenóis/análise , Polifenóis/análise , Polifenóis/química , Espectrometria de Massas em Tandem/métodos , Chá/classificação , Chá/normas , alfa-Glucosidases/metabolismo
13.
Food Chem ; 242: 527-532, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29037724

RESUMO

Tea polyphenols (TP) were emulsified with corn oil and polysorbate 80 by high-pressure homogenization. The oil in water (O/W) TP nanoemulsion had droplet sizes of 99.42±1.25nm after preparation. The TP nanoemulsion was stable during storage at 4, 25 or 40°C for 20days. An in vitro simulated digestion assay showed that the bioaccessibility of (-)-epigallocatechin gallate (EGCG) was increased in the nanoemulsion compared to that in aqueous solution, but that the bioaccessibilities of (-)-epigallocatechin (EGC), (-)-epicatechin (EC) and (-)-gallocatechin gallate (GCG) were greatly decreased. Compared with rats fed an aqueous TP solution, rats fed the TP nanoemulsion had significantly lower maximum plasma concentrations (Cmax) of EGCG and EGC, but the area under the plasma concentration-time curve (AUC0-t) was increased. The data show that use of a nanoemulsion system to deliver tea polyphenols may enhance the absorption of EGCG through controlled release.


Assuntos
Catequina/análogos & derivados , Sistemas de Liberação de Medicamentos/métodos , Nanoestruturas/química , Extratos Vegetais/química , Polifenóis/química , Animais , Disponibilidade Biológica , Camellia sinensis/química , Catequina/química , Catequina/farmacocinética , Emulsões/química , Masculino , Extratos Vegetais/farmacocinética , Polifenóis/farmacocinética , Ratos , Ratos Sprague-Dawley
14.
Food Funct ; 8(2): 687-694, 2017 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-28124052

RESUMO

In this study, the inhibitory effects of loquat leaf extract (LLE) on pancreatic α-amylase and α-glucosidase, and the preventative effects of LLE on hyperlipidemia and hyperglycemia in rats induced by a high fat and fructose diet have been evaluated. The LLE was chemically described using a high performance liquid chromatography-diode array detector coupled with a mass spectrometer (HPLC-DAD-MS/MS). 20 compounds including phenolic acids, flavonoids and triterpene acids were tentatively identified with authentic compounds or by referring to published articles and accessible databases (e.g. MassBank, METLIN). Enzyme activity measurements showed that the IC50 values of the LLE on α-amylase and α-glucosidase were 11.34 ± 1.04 mg mL-1 and 50.77 ± 1.04 µg mL-1, respectively. The calculated Michaelis-Menten constants indicated that the LLE is an effective inhibitor against α-glucosidase in a mixed-model competitive mode. The fluorescence data revealed that the LLE binds with α-amylase and α-glucosidase. The animal experiment results indicated that the LLE significantly decreased the levels of fasting blood glucose, and hepatic and serum triglycerides.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Eriobotrya/química , Frutose/efeitos adversos , Hiperglicemia/tratamento farmacológico , Hiperlipidemias/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Animais , Cromatografia Líquida de Alta Pressão , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/química , Frutose/metabolismo , Humanos , Hiperglicemia/enzimologia , Hiperglicemia/metabolismo , Hiperlipidemias/enzimologia , Hiperlipidemias/metabolismo , Cinética , Masculino , Extratos Vegetais/química , Folhas de Planta/química , Ratos , Espectrometria de Massas em Tandem , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/química , alfa-Amilases/metabolismo , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo
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