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1.
Food Res Int ; 188: 114525, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823888

RESUMO

As a kind of green tea with unique multiple baking processes, the flavor code of Lu'an Guapian (LAGP) has recently been revealed. To improve and stabilize the quality of LAGP, further insight into the dynamic changes in odorants during the whole processing is required. In this study, 50 odorants were identified in processing tea leaves, 14 of which were selected for absolute quantification to profile the effect of processes. The results showed that spreading is crucial for key aroma generation and accumulation, while these odorants undergo significant changes at the deep baking stage. By adjusting the conditions of the spreading and deep baking, it was found that low-temperature (4 °C) spreading for 6 h and low-temperature with long-time baking (final leaf temperature: 102 °C, 45 min) could improve the overall aroma quality. These results provide a new direction for enhancing the quality of LAGP green tea.


Assuntos
Odorantes , Chá , Compostos Orgânicos Voláteis , Odorantes/análise , Chá/química , Compostos Orgânicos Voláteis/análise , Folhas de Planta/química , Manipulação de Alimentos/métodos , Culinária/métodos , Camellia sinensis/química , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta
2.
Carbohydr Polym ; 339: 122239, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823909

RESUMO

A new zirconium and cerium-modified polyvinyl alcohol (PVA) sodium carboxymethyl cellulose (NaCMC) film (PVA/CMC-Zr-Ce) was synthesized thru a high-speed shear-assisted method and its adsorption for the removal of fluoride was studied, in which the NaCMC provided -COONa for ion exchange between Na and Zr-Ce, thus the loading amount of Zr-Ce on films was accordingly increased. The morphology and structure of PVA/CMC-Zr-Ce were characterized using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD). Besides, the mechanical properties, water contact angle, and swelling ratio of film were also evaluated. The addition of high-speed shear improved the dispersion of the emulsion system, and PVA/CMC-Zr-Ce film with good adsorption performance and film stability was prepared. While, it was found that the adsorption capacity could reach 67.25 mg/g and equilibrium time could reach 20 min. The adsorption mechanism of PVA/CMC-Zr-Ce revealed that ion exchange between hydroxide and fluoride, electrostatic interactions and complexation were the dominating influencing factors. Based on these findings, it can be concluded that PVA/CMC-Zr-Ce film- synthesized with high-speed shear assistance technique is a promising adsorbent for fluoride removal from water.

3.
ACS Omega ; 9(19): 20849-20858, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38764681

RESUMO

Deep, high-temperature carbonate reservoirs, represented by the Chuanzhong-Gaomo Block and the Penglai Gas Field, have become important supports for increased storage and production in Sichuan Basin. However, acidization in high-temperature to ultrahigh-temperature reservoirs faces several technical challenges, such as fast acid-rock reaction rates, limited acid corrosion distances, and high risks of tubular corrosion. In this study, a novel high-temperature-resistant microencapsulated gelling agent GLE-3 was prepared using N-isopropylacrylamide (NIPAM) as the wall material, acrylamide (AM), 2-acrylamido-2-methylpropanesulfonic acid (AMPS), and N-vinylcaprolactam (NVCL) as the core materials, and N,N'-methylenebis(acrylamide) (MBA) as the cross-linking agent through inverse emulsion polymerization. GLE-3 was structurally characterized using infrared spectroscopy, transmission electron microscopy, and particle size analysis, and its properties were evaluated. The results showed that GLE-3 exhibited uniform particle size distribution ranging from 10 to 100 µm. Under high-temperature conditions of 180 °C and a shear rate of 170 s-1, the viscosity of the gel acid solution remained above 27.8 mPa·s, with a viscosity retention rate of 63.76%. Compared to GLE-1 (uncapsulated), GLE-3 demonstrated improved thermal stability and shear stability after microencapsulation. After 60 min of shearing at 180 °C and shear rate of 170 s-1, the viscosity retention rate was 88.99%. Furthermore, under 180 °C conditions, GLE-3 exhibited good high-temperature slow-release performance compared to GLE-1, which unencapsulated with the same raw materials. By increasing the viscosity of the gel acid, delaying the acid-rock reaction rate, and providing high-temperature slow-release effects, the high-temperature resistance of the acid system was enhanced, ultimately achieving deep acidization in high-temperature reservoirs.

4.
Food Funct ; 15(11): 6068-6081, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38757391

RESUMO

Epigallocatechin gallate (EGCG), a prominent bioactive compound found in tea, offers numerous health benefits. Previous studies have highlighted its potential in mitigating hyperuricemia. In this study, hyperuricemic mice induced by potassium oxonate (PO) were treated with EGCG or the anti-hyperuricemia medication allopurinol (AP) to investigate the mechanisms underlying their anti-hyperuricemic effects. The results demonstrated that both EGCG and AP significantly reduced serum uric acid (UA) levels. Further analysis revealed that EGCG promoted the expression of UA secretion transporter genes (Oat1 and Oct1) while inhibiting the expression of UA reabsorption transporter genes (Urat1 and Glut9) in the kidney. By 16S rDNA sequencing, EGCG, but not AP, was found to alter the composition of the gut microbiota. Notably, EGCG induced significant changes in the relative abundance of specific bacteria such as Lactobacillus, Faecalibaculum, and Bifidobacterium, which displayed high correlations with serum UA levels and UA-related gene expression. Metabolomic analysis suggested that EGCG-induced modifications in bacterial metabolites might contribute to the alleviation of hyperuricemia. Transcriptomic analysis of the intestinal epithelium identifies 191 differentially expressed genes (DEGs) in EGCG-treated mice, including 8 purine-related genes. This study elucidates the anti-hyperuricemic mechanisms of EGCG, particularly its influence on the gut microbiota and gene expression in the intestinal epithelium.


Assuntos
Catequina , Modelos Animais de Doenças , Microbioma Gastrointestinal , Hiperuricemia , Ácido Úrico , Animais , Hiperuricemia/tratamento farmacológico , Catequina/análogos & derivados , Catequina/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Camundongos , Masculino , Ácido Úrico/sangue , Ácido Úrico/metabolismo , Camundongos Endogâmicos C57BL , Alopurinol/farmacologia , Rim/efeitos dos fármacos , Rim/metabolismo , Transportadores de Ânions Orgânicos/metabolismo , Transportadores de Ânions Orgânicos/genética , Ácido Oxônico , Intestinos/efeitos dos fármacos , Intestinos/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Proteínas Facilitadoras de Transporte de Glucose
5.
Food Res Int ; 184: 114266, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38609242

RESUMO

The capacity differences of seven catechin monomers to produce colors after treating with catechin-free extract were investigated. After 240-min reaction, only (-)-epicatechin (EC) and (+)-catechin (C) presented obvious luminous red color with L* values of 63.32-71.73, a* values of 37.13-46.44, and b* values of 65.64-69.99. Meanwhile, the decrease rate of EC and C was 43.52 %-50.35 %, which were significantly lower than those of other catechin monomers (85.91 %-100 %). The oxidized products of catechin monomers were analyzed by ultra-high performance liquid chromatography-quadrupole-time of flight-mass spectrometry coupled with diode array detector, wherein dehydro-dimers and -trimers (oxidative coupling products of catechins' A-B ring) were found to be the major chromogenic compounds of EC and C. Additionally, the antioxidant capacity of catechin monomers only decreased after 30-min reaction, while along with further enzymatic reaction, catechin monomers presented comparable oxyradical scavenging ability (e.g., the DPPH inhibitory rates of catechin monomers were in the range of 24.42 %-50.77 %) to vitamin C (positive control, DPPH inhibitory rate was 27.66 %). Meanwhile, the inhibitory effects of most catechin monomers on α-glucosidase were enhanced in different degrees. These results provided basis for the development of enzymatically-oxidized catechin monomers as functional food color additives.


Assuntos
Catequina , Colorimetria , Espectrometria de Massas , Espectrometria de Massa com Cromatografia Líquida , Antioxidantes
6.
Front Nutr ; 11: 1371401, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38510712

RESUMO

Proteins and polyphenols are abundant in the daily diet of humans and their interactions influence, among other things, the texture, flavor, and bioaccessibility of food. There are two types of interactions between them: non-covalent interactions and covalent interactions, the latter being irreversible and more powerful. In this review, we systematically summarized advances in the investigation of possible mechanism underlying covalent polyphenols-proteins interaction in food processing, effect of different processing methods on covalent interaction, methods for characterizing covalent complexes, and impacts of covalent interactions on protein structure, function and nutritional value, as well as potential bioavailability of polyphenols. In terms of health promotion of the prepared covalent complexes, health effects such as antioxidant, hypoglycemic, regulation of intestinal microbiota and regulation of allergic reactions have been summarized. Also, the possible applications in food industry, especially as foaming agents, emulsifiers and nanomaterials have also been discussed. In order to offer directions for novel research on their interactions in food systems, nutritional value, and health properties in vivo, we considered the present challenges and future perspectives of the topic.

7.
J Econ Entomol ; 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38517276

RESUMO

Sex pheromone analogs have high structural similarity to sex pheromone components. They also play a role in studying many agricultural pests. In our study, (Z, Z, Z)-3,6,9-nonadecadiene (Z3Z6Z9-19:Hy) was successfully synthesized, which is an analogue to 1 of 2 sex pheromone components of Ectropis grisescens Warren (Z, Z, Z)-3,6,9-octadecatriene (Z3Z6Z9-18:Hy), and it showed potential inhibition in experiments. In the electroantennogram test, Z3Z6Z9-19:Hy showed a dose-dependent response, and only measured half the response of Z3Z9-6,7-epo-18:Hy. However, the compound significantly reduced positive response of E. grisescens males by up to 70% in the Y-tube olfactometer. Furthermore, in the wind tunnel, it significantly inhibited all types of behavioral responses. The percentage of moths contacting the pheromone odor source was reduced even at the lowest dose tested. In silico study afterward, molecular docking results showed affinity between Z3Z6Z9-19:Hy and sensory neuron membrane protein 1. Our study revealed the potential of Z3Z6Z9-19:Hy as a sex pheromone inhibitor, which would provide new tools for monitoring and mating disruption of E. grisescens.

8.
Hortic Res ; 11(3): uhae012, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38464471

RESUMO

Theanine metabolism is a necessary biological process during the planting and production of tea that determines tea quality. There is currently little knowledge about the transcriptional regulation of theanine metabolism in tea plants. In this study, we demonstrated that γ-glutamyl-transpeptidase CsGGT4, as a homologous protein of the theanine hydrolase CsGGT2, exhibited a higher theanine synthesis catalytic efficiency. Homology modeling and molecular docking showed that differential protein structures between CsGGT2 and CsGGT4 implied their different biological functions in tea plants. Theanine content correlated significantly with the expression of CsGGT2, CsGGT4 and the transcription factor CsMYB73 in tea shoots from different seasons. Additionally, CsMYB73 was confirmed to act as a nucleus-localized transcription factor (TF), directly interacts with the CsGGT2 and CsGGT4 promoters, serving as an activator of CsGGT2 and a suppressor of CsGGT4. Consequently, this leads to a negative association with theanine accumulation in tea shoots. Furthermore, the continuous increase in CsMYB73 produced a significantly increase in CsGGT2 expression and inhibited CsGGT4 expression. The present study reveals that the degradation of theanine has been observed to increase, concomitantly with the inhibition of theanine synthesis, resulting in a significant decline in the accumulation of theanine in tea shoots during the process of seasonal greening in 'Huangkui' leaves. This study contributes to the broader comprehension of the intricate transcriptional regulatory hierarchy that governs the metabolism of theanine in tea shoots, offering novel approaches for managing tea plantations and enhancing tea quality.

9.
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
10.
Food Chem ; 445: 138620, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38382249

RESUMO

Gabaron green tea (GAGT) has unique flavor and health benefits through the special anaerobic treatment. However, how this composite processing affects the aroma formation of GAGT and the regulatory mechanism was rarely reported. This study used nontargeted metabolomics and molecular sensory science to overlay screen differential metabolites and key aroma contributors. The potential regulatory mechanism of anaerobic treatment on the aroma formation of GAGT was investigated by transcriptomics and correlation analyses. Five volatiles: benzeneacetaldehyde, nonanal, geraniol, linalool, and linalool oxide III, were screened as target metabolites. Through the transcriptional-level differential genes screening and analysis, some CsERF transcription factors in the ethylene signaling pathway were proposed might participate the response to the anaerobic treatment. They might regulate the expression of related genes in the metabolic pathway of the target metabolites thus affecting the GAGT flavor. The findings of this study provide novel information on the flavor and its formation of GAGT.


Assuntos
Camellia sinensis , Compostos Orgânicos Voláteis , Chá/metabolismo , Camellia sinensis/genética , Camellia sinensis/metabolismo , Multiômica , Compostos Orgânicos Voláteis/análise , Cromatografia Gasosa-Espectrometria de Massas , Odorantes/análise
11.
J Agric Food Chem ; 72(8): 3984-3997, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38357888

RESUMO

Plant secondary metabolites are critical quality-conferring compositions of plant-derived beverages, medicines, and industrial materials. The accumulations of secondary metabolites are highly variable among seasons; however, the underlying regulatory mechanism remains unclear, especially in epigenetic regulation. Here, we used tea plants to explore an important epigenetic mark DNA methylation (5mC)-mediated regulation of plant secondary metabolism in different seasons. Multiple omics analyses were performed on spring and summer new shoots. The results showed that flavonoids and theanine metabolism dominated in the metabolic response to seasons in the new shoots. In summer new shoots, the genes encoding DNA methyltransferases and demethylases were up-regulated, and the global CG and CHG methylation reduced and CHH methylation increased. 5mC methylation in promoter and gene body regions influenced the seasonal response of gene expression; the amplitude of 5mC methylation was highly correlated with that of gene transcriptions. These differentially methylated genes included those encoding enzymes and transcription factors which play important roles in flavonoid and theanine metabolic pathways. The regulatory role of 5mC methylation was further verified by applying a DNA methylation inhibitor. These findings highlight that dynamic DNA methylation plays an important role in seasonal-dependent secondary metabolism and provide new insights for improving tea quality.


Assuntos
Camellia sinensis , Metilação de DNA , Metabolismo Secundário , Estações do Ano , Epigênese Genética , Folhas de Planta/genética , Folhas de Planta/metabolismo , Camellia sinensis/genética , Camellia sinensis/metabolismo , Flavonoides/metabolismo , Chá/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
12.
J Colloid Interface Sci ; 661: 1060-1069, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38335790

RESUMO

Herein, a novel dual-mode probe for organophosphorus pesticides (OPs) colorimetric and photothermal detection was developed based on manganese modified porphyrin metal-organic framework (PCN-224-Mn). PCN-224-Mn had excellent oxidase-like activity and oxidized colorless 3,3,5,5-tetramethylbenzidine (TMB) to blue-green oxidation state TMB (oxTMB), which exhibited high temperature under near-infrared irradiation. l-ascorbate-2-phosphate was hydrolyzed by acid phosphatase to produce ascorbic acid, which weakened colorimetric and photothermal signals by impacting oxTMB generation. The presence of OPs blocked the production of ascorbic acid by irreversibly inhibiting the activity of acid phosphatase, causing the restoration of chromogenic reaction and the increase of temperature. Under the optimal conditions, the probe showed a good linear response to OPs in the concentration range of 5 âˆ¼ 10000 ng/mL, using glyphosate as the analog. The detection limits of glyphosate in colorimetric mode and photothermal mode were 1.47 ng/mL and 2.00 ng/mL, respectively. The probe was successfully used for sensitive identification of OPs residues in tea, brown rice, and wheat flour. This work proposes a simple and reliable colorimetric/photothermal platform for OPs identification, which overcomes the problem that single-mode detection probes are susceptible to external factors, and has broad application potential in the field of food safety.


Assuntos
Benzidinas , Estruturas Metalorgânicas , Praguicidas , Compostos Organofosforados , Colorimetria , Farinha , Triticum , Ácido Ascórbico/química , Fosfatase Ácida
13.
Arch Pathol Lab Med ; 148(4): 461-470, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37406289

RESUMO

CONTEXT.­: Breast cancer with low (1%-10%) estrogen receptor (ER) expression (ER-low positive) constitutes a small portion of invasive breast cancers, and the treatment strategy for these tumors remains debatable. OBJECTIVE.­: To characterize the features and outcomes of ER-low positive patients, and clarify the clinical significance of FOXC1 and SOX10 expression in ER-low positive/HER2-negative tumors. DESIGN.­: Among 9082 patients diagnosed with primary invasive breast cancer, the clinicopathologic features of those with ER-low positive breast cancer were characterized. FOXC1 and SOX10 mRNA levels were analyzed in ER-low positive/HER2-negative cases from public data sets. The expression of FOXC1 and SOX10 in ER-low positive/HER2-negative tumors was evaluated by immunohistochemistry. RESULTS.­: The clinicopathologic study of ER-low positive tumors indicated more aggressive characteristics compared with those tumors with ER >10%, while they had more overlapping features with ER-negative tumors irrespective of the HER2 status. The intrinsic molecular subtype of ER-low positive cases with high FOXC1 and SOX10 mRNA expression was more likely to be nonluminal. Among the ER-low positive/HER2-negative tumors, 56.67% (51 of 90) and 36.67% (33 of 90) were positive for FOXC1 and SOX10, respectively, which was significantly positively correlated with CK5/6 expression. In addition, the survival analysis demonstrated no significant difference between patients who received and who did not receive endocrine therapy. CONCLUSIONS.­: ER-low positive breast cancers biologically overlap more with ER-negative tumors. ER-low positive/HER2-negative cases demonstrate a high rate of FOXC1 or SOX10 expression, and these cases might be better categorized as a basal-like phenotype/subtype. FOXC1 and SOX10 testing may be used for the intrinsic phenotype prediction for ER-low positive/HER2-negative patients.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Neoplasias da Mama/tratamento farmacológico , Receptor ErbB-2/análise , Fenótipo , Biomarcadores Tumorais/análise , Receptores de Estrogênio/análise , RNA Mensageiro/genética , Receptores de Progesterona/análise , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição SOXE/genética
14.
Nucleic Acids Res ; 52(D1): D1661-D1667, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37650644

RESUMO

The genus Camellia consists of about 200 species, which include many economically important species widely used for making tea, ornamental flowers and edible oil. Here, we present an updated tea plant information archive for Camellia genomics (TPIA2; http://tpia.teaplants.cn) by integrating more novel large-scale genomic, transcriptomic, metabolic and genetic variation datasets as well as a variety of useful tools. Specifically, TPIA2 hosts all currently available and well assembled 10 Camellia genomes and their comprehensive annotations from three major sections of Camellia. A collection of 15 million SNPs and 950 950 small indels from large-scale genome resequencing of 350 diverse tea accessions were newly incorporated, followed by the implementation of a novel 'Variation' module to facilitate data retrieval and analysis of the functionally annotated variome. Moreover, 116 Camellia transcriptomes were newly assembled and added, leading to a significant extension of expression profiles of Camellia genes to 13 developmental stages and eight abiotic/biotic treatments. An updated 'Expression' function has also been implemented to provide a comprehensive gene expression atlas for Camellia. Two novel analytic tools (e.g. Gene ID Convert and Population Genetic Analysis) were specifically designed to facilitate the data exchange and population genomics in Camellia. Collectively, TPIA2 provides diverse updated valuable genomic resources and powerful functions, and will continue to be an important gateway for functional genomics and population genetic studies in Camellia.


Assuntos
Camellia , Bases de Dados Genéticas , Camellia/genética , Camellia sinensis/genética , Camellia sinensis/metabolismo , Genoma de Planta , Genômica , Chá/metabolismo
15.
Immunology ; 171(1): 60-76, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37753964

RESUMO

Tumorigenesis entails circumventing cell-intrinsic regulatory mechanisms while avoiding extrinsic immune surveillance and other host defence systems. Nevertheless, how tumour cells' ability to eliminate misfolded proteins affects immune surveillance remains poorly understood. In this study, we find that overexpression of murine tripartite motif-containing protein 30a (TRIM30a) sensitises tumour cells to natural killer (NK) cells-mediated cytolysis. TRIM30a has no effect on tumour cell proliferation or apoptosis in vitro. However, TRIM30a-overexpressing tumour cells grow substantially slower than control tumour cells in immune-competent mice but not in NK cell-depleted mice. [Correction added on 04 October 2023, after first online publication: 'NK-depleted' has been changed to 'NK cell-depleted' in the preceding sentence.] Mechanistically, TRIM30a overexpression impedes the clearance of misfolded proteins and increases the production of reactive oxygen species induced by proteotoxic stress, implying that TRIM30a impairs protein quality control (PQC) systems in tumour cells. Furthermore, TRIM30a reduces expression of genes encoding proteasome subunits and antioxidant proteins. Our study demonstrates that TRIM30a is a potential tumour suppressor and immune modulator that promotes tumour cytolysis by NK cells, and suggests that an enhanced PQC and antioxidant capacity is an integral part of the immune escape mechanism during tumorigenesis.


Assuntos
Antioxidantes , Neoplasias , Animais , Camundongos , Antioxidantes/metabolismo , Carcinogênese/metabolismo , Células Matadoras Naturais , Espécies Reativas de Oxigênio/metabolismo
16.
Ecotoxicol Environ Saf ; 266: 115568, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37832482

RESUMO

The tea plant accumulates elevated levels of fluoride (F) from environmental sources. Drinking tea containing high F levels poses a potential threat to human health. Selenium (Se) was applied by foliar spray to investigate its effects on F accumulation and physiology in tea plant. Foliar application of different forms of Se, i.e., Na2SeO3, Kappa-selenocarrageenan, Selenomethionine and Nanoselenium, reduced F content in tea leaves by 10.17 %-44.28 %, 16.12 %-35.41 %, 22.19 %-45.99 % and 22.24 %-43.82 %, respectively. Foliar spraying Se could increase F accumulation in pectin through increasing pectin content and pectin demethylesterification to bind more F in the cell wall, which decreased the proportion of water-soluble fluoride in tea leaves. Application of Se significantly decreased the contents of chromium (39.6 %-72.0 %), cadmium (48.3 %-84.4 %), lead (2.2 %-44.4 %) and copper (14.1 %-44.6 %) in tea leaves. Foliar spraying various forms of Se dramatically increased the Se content and was efficiently transformed into organic Se accounting for more than 80 % in tea leaves. All Se compounds increased peroxidase activity by 3.3 %-35.5 % and catalase activity by 2.6 %-99.4 %, reduced malondialdehyde content by 5.6 %-37.1 %, and increased the contents of chlorophyll by 0.65 %-31.8 %, carotenoids by 0.24 %-27.1 %, total catechins by 1.6 %-21.0 %, EGCG by 4.4 %-17.6 % and caffeine by 9.1 %-28.6 %. These results indicated that Se application could be served as a potential efficient and safe strategy diminishing the concentration of F in tea leaves.


Assuntos
Camellia sinensis , Selênio , Humanos , Selênio/metabolismo , Fluoretos/análise , Antioxidantes/metabolismo , Camellia sinensis/química , Folhas de Planta/metabolismo , Chá , Pectinas/metabolismo
17.
Hortic Res ; 10(10): uhad184, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37885816

RESUMO

Geraniol is an important contributor to the pleasant floral scent of tea products and one of the most abundant aroma compounds in tea plants; however, its biosynthesis and physiological function in response to stress in tea plants remain unclear. The proteins encoded by the full-length terpene synthase (CsTPS1) and its alternative splicing isoform (CsTPS1-AS) could catalyze the formation of geraniol when GPP was used as a substrate in vitro, whereas the expression of CsTPS1-AS was only significantly induced by Colletotrichum gloeosporioides and Neopestalotiopsis sp. infection. Silencing of CsTPS1 and CsTPS1-AS resulted in a significant decrease of geraniol content in tea plants. The geraniol content and disease resistance of tea plants were compared when CsTPS1 and CsTPS1-AS were silenced. Down-regulation of the expression of CsTPS1-AS reduced the accumulation of geraniol, and the silenced tea plants exhibited greater susceptibility to pathogen infection than control plants. However, there was no significant difference observed in the geraniol content and pathogen resistance between CsTPS1-silenced plants and control plants in the tea plants infected with two pathogens. Further analysis showed that silencing of CsTPS1-AS led to a decrease in the expression of the defense-related genes PR1 and PR2 and SA pathway-related genes in tea plants, which increased the susceptibility of tea plants to pathogens infections. Both in vitro and in vivo results indicated that CsTPS1 is involved in the regulation of geraniol formation and plant defense via alternative splicing in tea plants. The results of this study provide new insights into geraniol biosynthesis and highlight the role of monoterpene synthases in modulating plant disease resistance via alternative splicing.

18.
Adv Food Nutr Res ; 106: 129-218, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37722772

RESUMO

As one of the most consumed non-alcoholic beverages in the world, tea is acclaimed for its pleasant flavor and various health benefits. Different types of tea present a distinctive flavor and bioactivity due to the changes in the composition and proportion of respective compounds. This article aimed to provide a more comprehensive understanding of tea flavor (including aroma and taste) and the character of tea in preventing and alleviating diseases. The recent advanced modern analytical techniques for revealing flavor components in tea, including enrichment, identification, quantitation, statistics, and sensory evaluation methodologies, were summarized in the following content. Besides, the role of tea in anti-cancer, preventing cardiovascular disease and metabolic syndrome, anti-aging and neuroprotection, and regulating gut microbiota was also listed in this article. Moreover, questions and outlooks were mentioned to objectify tea products' flavor quality and health benefits on a molecular level and significantly promote our understanding of the comprehensive value of tea as a satisfactory health beverage in the future.


Assuntos
Bebidas , Doenças Cardiovasculares , Humanos , Percepção , Chá
19.
Food Res Int ; 172: 113186, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37689937

RESUMO

The elegant orchid-like fragrance of tea has always been tea processors and consumers' top priority. Controlling the production process is very important for tea aroma formation. This study aims to investigate the synthesis of (Z)-methyl epijasmonate (epi-MeJA), a key contributor to orchid-like aroma properties in tea, during tea processing. The changes in content of epi-MeJA were analysed during the processing of two tea varieties (Anxi Tieguanyin and Taiping Houkui) with typical orchid-like fragrance. It was found to be mainly synthesized and accumulated during tea processing, as fresh tea leaves contained little or even no epi-MeJA. Its content was positively correlated with the processing time in the enzyme active stages (before fixation). During the fixation stages, isomerization occurred due to high temperatures, with a degree of epimerization to the much less odor active isomer (Z)-methyl jasmonate. Isomerization could also occurred during the drying process, which is dominated by the drying temperature.


Assuntos
Acetatos , Odorantes , Isomerismo , Chá
20.
J Hematol Oncol ; 16(1): 97, 2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-37596653

RESUMO

Adoptive cell therapies (ACTs) have existed for decades. From the initial infusion of tumor-infiltrating lymphocytes to the subsequent specific enhanced T cell receptor (TCR)-T and chimeric antigen receptor (CAR)-T cell therapies, many novel strategies for cancer treatment have been developed. Owing to its promising outcomes, CAR-T cell therapy has revolutionized the field of ACTs, particularly for hematologic malignancies. Despite these advances, CAR-T cell therapy still has limitations in both autologous and allogeneic settings, including practicality and toxicity issues. To overcome these challenges, researchers have focused on the application of CAR engineering technology to other types of immune cell engineering. Consequently, several new cell therapies based on CAR technology have been developed, including CAR-NK, CAR-macrophage, CAR-γδT, and CAR-NKT. In this review, we describe the development, advantages, and possible challenges of the aforementioned ACTs and discuss current strategies aimed at maximizing the therapeutic potential of ACTs. We also provide an overview of the various gene transduction strategies employed in immunotherapy given their importance in immune cell engineering. Furthermore, we discuss the possibility that strategies capable of creating a positive feedback immune circuit, as healthy immune systems do, could address the flaw of a single type of ACT, and thus serve as key players in future cancer immunotherapy.


Assuntos
Neoplasias Hematológicas , Receptores de Antígenos Quiméricos , Humanos , Imunoterapia Adotiva , Imunoterapia , Engenharia Celular
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