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1.
Prev Med ; 184: 107997, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38729527

RESUMEN

OBJECTIVES: Public Health officials are often challenged to effectively allocate limited resources. Social determinants of health (SDOH) may cluster in areas to cause unique profiles related to various adverse life events. The authors use the framework of unintended teen pregnancies to illustrate how to identify the most vulnerable neighborhoods. METHODS: This study used data from the U.S. American Community Survey, Princeton Eviction Lab, and Connecticut Office of Vital Records. Census tracts are small statistical subdivisions of a county. Latent class analysis (LCA) was employed to separate the 832 Connecticut census tracts into four distinct latent classes based on SDOH, and GIS mapping was utilized to visualize the distribution of the most vulnerable neighborhoods. GEE Poisson regression model was used to assess whether latent classes were related to the outcome. Data were analyzed in May 2021. RESULTS: LCA's results showed that class 1 (non-minority non-disadvantaged tracts) had the least diversity and lowest poverty of the four classes. Compared to class 1, class 2 (minority non-disadvantaged tracts) had more households with no health insurance and with single parents; and class 3 (non-minority disadvantaged tracts) had more households with no vehicle available, that had moved from another place in the past year, were low income, and living in renter-occupied housing. Class 4 (minority disadvantaged tracts) had the lowest socioeconomic characteristics. CONCLUSIONS: LCA can identify unique profiles for neighborhoods vulnerable to adverse events, setting up the potential for differential intervention strategies for communities with varying risk profiles. Our approach may be generalizable to other areas or other programs. KEY MESSAGES: What is already known on this topic Public health practitioners struggle to develop interventions that are universally effective. The teen birth rates vary tremendously by race and ethnicity. Unplanned teen pregnancy rates are related to multiple social determinants and behaviors. Latent class analysis has been applied successfully to address public health problems. What this study adds While it is the pregnancy that is not planned rather than the birth, access to pregnancy intention data is not available resulting in a dependency on teen birth data for developing public health strategies. Using teen birth rates to identify at-risk neighborhoods will not directly represent the teens at risk for pregnancy but rather those who delivered a live birth. Since teen birth rates often fluctuate due to small numbers, especially for small neighborhoods, LCA may avoid some of the limitations associated with direct rate comparisons. The authors illustrate how practitioners can use publicly available SDOH from the Census Bureau to identify distinct SDOH profiles for teen births at the census tract level. How this study might affect research, practice or policy These profiles of classes that are at heightened risk potentially can be used to tailor intervention plans for reducing unintended teen pregnancy. The approach may be adapted to other programs and other states to prioritize the allocation of limited resources.


Asunto(s)
Sistemas de Información Geográfica , Análisis de Clases Latentes , Determinantes Sociales de la Salud , Humanos , Femenino , Adolescente , Embarazo , Connecticut , Características del Vecindario , Poblaciones Vulnerables/estadística & datos numéricos , Características de la Residencia/estadística & datos numéricos , Embarazo en Adolescencia/estadística & datos numéricos , Estados Unidos , Factores Socioeconómicos
2.
J Sci Food Agric ; 102(7): 2750-2760, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34719036

RESUMEN

BACKGROUND: The phenol oxidative pathway during fermentation remains unclear. To elucidate the effect of fermentation on phenol conversion, we investigated the effects of fermentation temperature and duration on the conversion of catechins and the formation of theasinensins (TSs), theaflavins (TFs), thearubigins (TRs), and theabrownins (TBs). RESULTS: During fermentation, TSs formation increased initially and then decreased. Long fermentation durations were unfavorable for liquor brightness (LB) and resulted in the production of large amounts of TRs and TBs. Low fermentation temperatures (20 °C and 25 °C) favored the maintenance of polyphenol oxidase activity and the continuous formation of TFs, TSs, and TRSI (a TRs fraction), resulting in better LB and liquor color. Higher temperatures (30 °C, 35 °C, and 40 °C) resulted in higher peroxidase activity, higher oxidative depletion rates of catechins, and excessive production of TRSII (a TRs fraction) and TBs. Analysis of the conversion pathway of polyphenolic compounds during fermentation showed that, during early fermentation, large amounts of catechins were oxidized and converted to TFs and theasinensin B. As fermentation progressed, considerable amounts of theaflavin-3'-gallate, theasinensin A, theaflavin-3-gallate, theaflavin-3,3'-digallate, and theasinensin C were produced and then converted to TRSI; in the final stage, TRSII and TBs were converted continuously. CONCLUSION: Different fermentation temperature and duration combinations directly affected the type and composition of phenolic compounds. The key conditions for controlling phenolic compound conversion and fermentation direction were 60 or 90 min and 25 or 30 °C. Our study provides insights into the regulation of phenolic compound conversion during black tea fermentation. © 2021 Society of Chemical Industry.


Asunto(s)
Biflavonoides , Camellia sinensis , Catequina , Antioxidantes/análisis , Biflavonoides/análisis , Camellia sinensis/química , Catequina/análisis , Fermentación , Fenol/análisis , Té/química , Temperatura
3.
Angew Chem Int Ed Engl ; 60(13): 7082-7086, 2021 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-33372348

RESUMEN

α-(Hetero)aryl nitriles are important structural motifs for pharmaceutical design. The known methods for direct synthesis of these compounds via coupling with (hetero)aryl halides suffer from narrow reaction scope. Herein, we report that the combination of copper salts and oxalic diamides enables the coupling of a variety of (hetero)aryl halides (Cl, Br) and ethyl cyanoacetate under mild conditions, affording α-(hetero)arylacetonitriles via one-pot decarboxylation. Additionally, the CuBr/oxalic diamide catalyzed coupling of (hetero)aryl bromides with α-alkyl-substituted ethyl cyanoacetates proceeds smoothly at 60 °C, leading to the formation of α-alkyl (hetero)arylacetonitriles after decarboxylation. The method features a general substrate scope and is compatible with various functionalities and heteroaryls.

4.
J Am Chem Soc ; 141(8): 3541-3549, 2019 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-30688450

RESUMEN

A robust and practical protocol for preparing alkyl aryl ethers has been developed, which relies on using two types of ligands to promote Cu-catalyzed alkoxylation of (hetero)aryl halides. The reaction scope is very general for a variety of coupling partners, particularly for challenging secondary alcohols and (hetero)aryl chlorides. In case of coupling with aryl chlorides and bromides, two oxalic diamides serve as the powerful ligands. The tert-butoxide is first demonstrated as a ligand for Cu-catalyzed coupling reaction, leading to alkoxylation of aryl iodides complete at room temperature. Additionally, a number of carbohydrate derivatives are applicable for this coupling reaction, affording the corresponding carbohydrate-aryl ethers in 29-98% yields.

5.
Molecules ; 24(23)2019 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-31757064

RESUMEN

The sweet-mellow taste sensation is a unique and typical feature of premium congou black tea infusions. To explore the key taste-active compounds that influence the sweet-mellow taste, a sensory and molecular characterization was performed on thirty-three congou black tea infusions presenting different taste qualities, including the sweet-mellow, mellow-pure, or less-mellow taste. An integrated application of quantitative analysis of 48 taste-active compounds, taste contribution analysis, and further validation by taste supplementation experiments, combined with human sensory evaluation revealed that caffeine, γ-aminobutyric acid, rutin, succinic acid, citric acid, and gallic acid negatively affect the sweet-mellow taste, whereas glucose, sucrose, and ornithine positively contribute to the sweet-mellow taste of congou black tea infusions. Particularly, rutin, γ-aminobutyric acid, gallic acid, and caffeine, which impart the major inhibitory effect to the manifestation of the sweet-mellow taste, were identified as the key influencing components through stepwise screening and validation experiments. A modest level of these compounds was found to be favorable for the development and manifestation of the sweet-mellow taste. These compounds might potentially serve as the regulatory targets for oriented-manufacturing of high-quality sweet-mellow congou black tea.


Asunto(s)
Cafeína/análisis , Camellia sinensis/química , Ácido Gálico/análisis , Rutina/análisis , Gusto , Té/química , Ácido gamma-Aminobutírico/análisis , Camellia sinensis/crecimiento & desarrollo , Femenino , Humanos , Masculino
6.
J Public Health Manag Pract ; 25(2): 137-146, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-29521848

RESUMEN

CONTEXT: National data on the epidemiology of firearm injuries and circumstances of firearm deaths are difficult to obtain and often are nonreliable. Since firearm injury and death rates and causes can vary substantially between states, it is critical to consider state-specific data sources. OBJECTIVE: In this study, we illustrate how states can systematically examine demographic characteristics, firearm information, type of wound, toxicology tests, precipitating circumstances, and costs to provide a comprehensive picture of firearm injuries and deaths using data sets from a single state with relatively low rates of firearm injury and death. DESIGN: Cross-sectional study. SETTING: Firearm-related injury data for the period 2005-2014 were obtained from the Rhode Island emergency department and hospital discharge data sets; death data for the same period were obtained from the Rhode Island Violent Death Reporting System. MAIN OUTCOME MEASURE: Descriptive statistics were used. Healthcare Cost and Utilization Project cost-to-charge ratios were used to convert total hospital charges to costs. RESULTS: Most firearm-related emergency department visits (55.8%) and hospital discharges (79.2%) in Rhode Island were from assaults; however, most firearm-related deaths were suicides (60.1%). The annual cost of firearm-related hospitalizations was more than $830 000. Most decedents who died because of firearms tested positive for illicit substances. Nearly a quarter (23.5%) of firearm-related homicides were due to a conflict between the decedent and suspect. More than half (59%) of firearm suicide decedents were reported to have had current mental or physical problems prior to death. CONCLUSIONS: Understanding the state-specific magnitude and patterns (who, where, factors, etc) of firearm injury and death may help inform local injury prevention efforts. States with similar data sets may want to adopt our analyses. Surveillance of firearm-related injury and death is essential. Dissemination of surveillance findings to key stakeholders is critical in improving firearm injury prevention. States that are not part of the National Violent Death Reporting System (NVDRS) could work with their other data sources to obtain a better picture of violent injuries and deaths to make the best use of resources.


Asunto(s)
Ciencia de los Datos/normas , Armas de Fuego/estadística & datos numéricos , Sistema de Registros/normas , Estudios Transversales , Ciencia de los Datos/métodos , Servicio de Urgencia en Hospital , Humanos , Alta del Paciente/estadística & datos numéricos , Vigilancia de la Población/métodos , Sistema de Registros/estadística & datos numéricos , Proyectos de Investigación , Rhode Island/epidemiología , Violencia/estadística & datos numéricos
7.
J Org Chem ; 83(12): 6589-6598, 2018 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-29786439

RESUMEN

The amide derived from 4-hydroxy-l-proline and 2,6-dimethylaniline is a powerful ligand for Cu-catalyzed coupling of (hetero)aryl halides with sulfinic acid salts, allowing the formation of a wide range of (hetero)aryl sulfones from the corresponding (hetero)aryl halides at considerably low catalytic loadings. The coupling of (hetero)aryl iodides and sodium methanesulfinate proceeds at room temperature with only 0.5 mol % CuI and ligand, representing the first example for Cu-catalyzed arylation at both low catalytic loading and room temperature.

8.
J Public Health Manag Pract ; 23(5): 499-506, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28009694

RESUMEN

CONTEXT: Drug overdoses are a growing public health problem in the United States. Rhode Island is also confronted with a serious epidemic of drug overdose deaths and ranks sixth worst in the United States for age-adjusted drug overdose death rate. OBJECTIVE: To monitor trends of drug overdose-related emergency department (ED) visits, hospitalizations, and deaths and classify the drug overdoses by demographics, discharge status, intent, and specific drug involved to plan for health care resource allocation, mental health services, drug abuse treatment, prevention, and policies. DESIGN: Cross-sectional study. SETTING: The 2005-2014 ED, hospital discharge, and death data were used for this study. MAIN OUTCOME MEASURE: Age-adjusted rates were calculated by using age-specific Rhode Island 2010 standard population. Healthcare Cost and Utilization Project cost-to-charge ratios were used to convert total hospital charges to costs. The descriptive analysis was performed. RESULTS: Hospitalizations generally represent the most severe cases; there are substantially fewer cases than are seen in the ED, and their characteristics are different from ED visits. More than half of the ED cases were an unintentional injury by drug overdose, but more than half of the hospital discharge data cases were a suicide/self-inflicted injury by drug overdose. There were typically much more females than males that result in a hospital admission. In Rhode Island, there were 249 drug overdose deaths in 2014. Drug overdose fatalities were more likely to be young, male, white, and those who reside in suburban regions. IMPLICATIONS: Nonfatal and fatal drug overdose data are important for understanding the scope, incidence, and breadth of this public health epidemic and can guide overdose intervention efforts. In Rhode Island, policy makers can use drug overdose data to target high-risk subpopulations to reduce overdose injuries and fatalities. The Rhode Island study can be shared with other states. CONCLUSIONS: Regardless of the type of drug, overdoses remain a public health crisis in Rhode Island. It is a dynamic epidemic and needs partnership among public health, behavioral health, public safety, clinic, pharmacy, and communities. The ability to track drug overdose in real time will be an essential tool to respond to the constantly evolving drug overdose epidemic in Rhode Island quickly and effectively.

9.
Angew Chem Int Ed Engl ; 56(51): 16136-16179, 2017 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-28544319

RESUMEN

Metal-catalyzed cross-coupling reactions belong to the most important transformations in organic synthesis. Copper catalysis has received great attention owing to the low toxicity and low cost of copper. However, traditional Ullmann-type couplings suffer from limited substrate scopes and harsh reaction conditions. The introduction of several bidentate ligands, such as amino acids, diamines, 1,3-diketones, and oxalic diamides, over the past two decades has totally changed this situation as these ligands enable the copper-catalyzed coupling of aryl halides and nucleophiles at both low reaction temperatures and catalyst loadings. The reaction scope has also been greatly expanded, rendering this copper-based cross-coupling attractive for both academia and industry. In this Review, we have summarized the latest progress in the development of useful reaction conditions for the coupling of (hetero)aryl halides with different nucleophiles. Additionally, recent advances in copper-catalyzed coupling reactions with aryl boronates and the copper-based trifluoromethylation of aromatic electrophiles will be discussed.

10.
Molecules ; 21(12)2016 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-28009849

RESUMEN

Catechins are polyphenolic phytochemicals with many important physiological activities that play a multifaceted health care function in the human body, especially in the prevention of cardiovascular disease. In this paper, various experimental and clinical studies have revealed the role of catechins in the prevention and treatment of cardiovascular disorders, and we review the preventive effects of catechins on cardiovascular disease from the following aspects: Regulating lipid metabolism, regulating blood lipid metabolism, vascular endothelial protection, and reducing blood pressure.


Asunto(s)
Antioxidantes/farmacología , Enfermedades Cardiovasculares/prevención & control , Catequina/farmacología , Endotelio Vascular/efectos de los fármacos , Té/química , Presión Sanguínea/efectos de los fármacos , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/fisiopatología , Endotelio Vascular/metabolismo , Endotelio Vascular/fisiopatología , Humanos , Metabolismo de los Lípidos/efectos de los fármacos , Prevención Primaria
11.
Angew Chem Int Ed Engl ; 55(21): 6211-5, 2016 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-27072902

RESUMEN

Couplings between (hetero)aryl chlorides and phenols can be effectively promoted by CuI in combination with an N-aryl-N'-alkyl-substituted oxalamide ligand to proceed smoothly at 120 °C. For this process, N-aryl-N'-alkyl-substituted oxalamides are more effective ligands than bis(N-aryl)-substituted oxalamides. A wide range of electron-rich and electron-poor aryl and heteroaryl chlorides gave the corresponding coupling products in good yields. Satisfactory conversions were achieved with electron-rich phenols as well as a limited range of electron-poor phenols. Catalyst and ligand loadings as low as 1.5 mol % are sufficient for the scaled-up variants of some of these reactions.

12.
J Am Chem Soc ; 137(37): 11942-5, 2015 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-26352639

RESUMEN

A class of oxalic diamides are found to be effective ligands for promoting CuI-catalyzed aryl amination with less reactive (hetero)aryl chlorides. The reaction proceeds at 120 °C with K3PO4 as the base in DMSO to afford a wide range of (hetero)aryl amines in good to excellent yields. The bis(N-aryl) substituted oxalamides are superior ligands to N-aryl-N'-alkyl substituted or bis(N-alkyl) substituted oxalamides. Both the electronic nature and the steric property of the aromatic rings in ligands are important for their efficiency.


Asunto(s)
Aminas/química , Cloro/química , Cobre/química , Diamida/química , Yoduros/química , Ácido Oxálico/química , Catálisis
13.
Prev Med ; 73: 139-44, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25602912

RESUMEN

OBJECTIVE: Most departments of health grapple with how to most effectively allocate resources to address chronic diseases. We adapted a model created by Massachusetts to create customized city/town profiles in order to identify the patterns of chronic disease among 39 cities/towns in Rhode Island. METHODS: We used four data sources to identify 20 indicators of four domains: demographics and socioeconomic status; health behaviors and chronic diseases prevalence; no regular provider and non-emergent emergency department visits; and chronic disease-related hospitalizations. A latent class model was used to group cities/towns into distinct latent class memberships based on similar patterns of indicators. Data were analyzed in 2014. RESULTS: The latent class model differentiated three distinct classes of city/town, reflecting three levels of economic and health indicators. CONCLUSIONS: Our model was a simplified version of one constructed by Massachusetts that larger states can also use to understand chronic disease patterns among cities/towns. Chronic disease programs and policies can use the findings to direct resources toward targets not always identified by more traditional analyses.


Asunto(s)
Enfermedad Crónica/epidemiología , Modelos Estadísticos , Población Urbana/estadística & datos numéricos , Sistema de Vigilancia de Factor de Riesgo Conductual , Servicio de Urgencia en Hospital/estadística & datos numéricos , Hospitalización/estadística & datos numéricos , Humanos , Rhode Island/epidemiología , Factores Socioeconómicos
14.
Biochemistry ; 53(33): 5414-23, 2014 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-25020031

RESUMEN

Most class A ß-lactamases cannot hydrolyze carbapenem antibiotics effectively. The molecular mechanism of this catalytic inefficiency has been attributed to the unique stereochemistry of carbapenems, including their 6-α-hydroxyethyl side chain and the transition between two tautomeric states when bound at the active site. Previous studies have shown that the 6-α-hydroxyethyl side chain of carbapenems can interfere with catalysis by forming hydrogen bonds with the deacylation water molecule to reduce its nucleophilicity. Here our studies of a class A noncarbapenemase PenP demonstrate that substituting the general base residue Glu166 with Ser or other residues leads to a significant enhancement of the acylation kinetics by ∼100-500 times toward carbapenems like meropenem. The structures of PenP and Glu166Ser both in apo form and in complex with meropenem reveal that Glu166 is critical for the formation of a hydrogen bonding network within the active site that locks Asn170 in an orientation to impose steric clash with the 6-α-hydroxyethyl side chain of meropenem. The Glu166Ser substitution weakens this network and enables Asn170 to adopt an alternative conformation to avoid steric clash and accommodate faster acylation kinetics. Furthermore, the weakened hydrogen bonding network caused by the Glu166Ser substitution allows the 6-α-hydroxyethyl moiety to adopt a catalytically favorable orientation as seen in class A carbapenemases. In summary, our data identify a previously unreported role of the universally conserved general base residue Glu166 in impeding the proper binding of carbapenems by restricting their 6-α-hydroxyethyl group.


Asunto(s)
Carbapenémicos/metabolismo , beta-Lactamasas/química , beta-Lactamasas/metabolismo , Acilación , Sustitución de Aminoácidos , Bacillus/enzimología , Sitios de Unión , Dominio Catalítico , Cefaloridina/química , Cristalografía por Rayos X , Ácido Glutámico/química , Cinética , Meropenem , Modelos Moleculares , Conformación Proteica , Tienamicinas/metabolismo , beta-Lactamasas/genética
15.
Foods ; 13(5)2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38472841

RESUMEN

Aroma is an indispensable factor that substantially impacts the quality assessment of black tea. This study aims to uncover the dynamic alterations in the sweet and floral aroma black tea (SFABT) throughout various manufacturing stages using a comprehensive analytical approach integrating gas chromatography electronic nose, gas chromatography-ion mobility spectrometry (GC-IMS), and gas chromatography-mass spectrometry (GC-MS). Notable alterations in volatile components were discerned during processing, predominantly during the rolling stage. A total of 59 typical volatile compounds were identified through GC-IMS, whereas 106 volatile components were recognized via GC-MS throughout the entire manufacturing process. Among them, 14 volatile compounds, such as linalool, ß-ionone, dimethyl sulfide, and 1-octen-3-ol, stood out as characteristic components responsible for SFABT with relative odor activity values exceeding one. This study serves as an invaluable theoretical platform for strategic controllable processing of superior-quality black tea.

16.
Food Res Int ; 178: 113876, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38309897

RESUMEN

The species and contents of ɑ-dicarbonyls in commercial black tea were examined, along with the effects of the manufacturing process and drying temperature on the formation of ɑ-dicarbonyls. Ten ɑ-dicarbonyls were quantified in commercial and in-process black tea samples by using UPLC-MS/MS and their derived quinoxalines. The ɑ-dicarbonyls content in commercial black tea decreased significantly (p < 0.05) in the following order: 3-deoxyglucosone > glucosone > 3-deoxypentosone = threosone > galactosone ≥ methylglyoxal = glyoxal ≥ 3-deoxygalactosone = 3-deoxythreosone = diacetyl. Except for 3-deoxyglucosone and 3-deoxygalactosone, a further eight ɑ-dicarbonyls were identified in all manufacturing steps of black tea. Except for the drying step, the rolling and fermenting played important roles in the formation of ɑ-dicarbonyls. The total contents of ɑ-dicarbonyls in black tea infusion ranged from 16.48 to 75.32 µg/g based on our detected ten ɑ-dicarbonyls.


Asunto(s)
Camellia sinensis , , Reacción de Maillard , Cromatografía Liquida , Espectrometría de Masas en Tándem , Glioxal/análisis
17.
Food Chem X ; 22: 101432, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38764783

RESUMEN

Aroma plays a pivotal role in the quality of black tea. However, the acceptability of black tea is greatly limited by the green off-flavor (GOF) resulting from the inappropriate processing control. In this study, the key odorants causing GOF were investigated by volatolomics, and their dynamic changes and formation pathways were in-depth understood. Significant alterations in volatile metabolites were observed in the withering stage. A total of 14 key odorants were identified as contributors to GOF, including 2-methylpropanal, 3-methylbutanal, 1-hexanol, nonanal, (E, E)-2,4-heptadienal, benzaldehyde, linalool, (E, E)-3,5-octadiene-2-one, ß-cyclocitral, phenylacetaldehyde, (E, E)-2,4-nonadienal, methyl salicylate, geraniol, and ß-ionone. Among them, (E, E)-2,4-heptadienal (OAV = 3913), characterized by fatty, green, and oily aromas, was considered to be the most important contributor causing GOF. Moreover, it was found that lipid degradation served as the primary metabolic pathway for GOF. This study provides a theoretical foundation for off-flavor control and quality improvement of black tea.

18.
Food Res Int ; 187: 114330, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38763633

RESUMEN

Processing technology plays a crucial role in the formation of tea aroma. The dynamic variations in volatile metabolites across different processing stages of fresh scent green tea (FSGT) were meticulously tracked utilizing advanced analytical techniques such as GC-E-Nose, GC-MS, and GC × GC-TOFMS. A total of 244 volatile metabolites were identified by GC-MS and GC × GC-TOFMS, among which 37 volatile compounds were concurrently detected by both methods. Spreading and fixation stages were deemed as pivotal processes for shaping the volatile profiles in FSGT. Notably, linalool, heptanal, 2-pentylfuran, nonanal, ß-myrcene, hexanal, 2-heptanone, pentanal, 1-octen-3-ol, and 1-octanol were highlighted as primary contributors to the aroma profiles of FSGT by combining odor activity value assessment. Furthermore, lipid degradation and glycoside hydrolysis were the main pathways for aroma formation of FSGT. The results not only elucidate the intricate variations in volatile metabolites but also offer valuable insights into enhancing the processing techniques for improved aroma quality of green tea.


Asunto(s)
Manipulación de Alimentos , Cromatografía de Gases y Espectrometría de Masas , Odorantes , , Compuestos Orgánicos Volátiles , Compuestos Orgánicos Volátiles/análisis , Compuestos Orgánicos Volátiles/metabolismo , Cromatografía de Gases y Espectrometría de Masas/métodos , Odorantes/análisis , Té/química , Manipulación de Alimentos/métodos , Nariz Electrónica , Aldehídos/análisis , Aldehídos/metabolismo , Monoterpenos Acíclicos/metabolismo , Monoterpenos Acíclicos/análisis , Camellia sinensis/química , Camellia sinensis/metabolismo , Cetonas/análisis , Cetonas/metabolismo , Octanoles
19.
Food Chem ; 439: 138154, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38071844

RESUMEN

Drying temperature (DT) considerably affects the flavor of black tea (BT); however, its influence on non-volatile metabolites (NVMs) and their correlations remain unclear. In this study, an objective quantification technique and widely targeted metabolomics were applied to explore the effects of DT (130 °C, 110 °C, 90 °C, and 70 °C) on BT flavor and NVMs conversion. BT with a DT of 90 °C presented the highest umami, sweetness, overall taste, and brightness color values. Using the weighted gene co-expression network and multiple factor analysis, 455 sensory trait-related NVMs were explored across six key modules. Moreover, 169 differential NVMs were screened, and flavonoids, phenolic acids, amino acids, organic acids, and lipids were identified as key differential NVMs affecting the taste and color attributes of BT in response to DT. These findings enrich the BT processing theory and offer technical support for the precise and targeted processing of high-quality BT.


Asunto(s)
Camellia sinensis , , Té/química , Temperatura , Camellia sinensis/química , Flavonoides/análisis , Metabolómica/métodos
20.
Food Chem X ; 23: 101519, 2024 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-38933990

RESUMEN

In the present study, the comprehensive quality of Congou black tea (CBT) including aroma, taste, and liquid color was investigated by a combination of gas chromatography electronic nose (GC-E-Nose), electronic tongue (E-tongue), and electronic eye (E-eye). An excellent discrimination of different quality grades of CBT was accomplished through the fusion of GC-E-Nose, E-tongue, and E-eye combined with orthogonal partial least squares discriminant analysis, with parameters of R2Y = 0.803 and Q2 = 0.740. Moreover, the quantitative evaluation of CBT quality was successfully achieved by partial least squares regression analysis, with the absolute error within 1.39 point, and the relative error within 1.62%. Additionally, 12 key variables were screened out by stepwise multiple linear regression analysis, which significantly contributed to the comprehensive quality score of CBT. Our results suggest that the fusion of multiple intelligent sensory technologies offers great potential and practicability in the quality evaluation of black tea.

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