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1.
Plant Physiol Biochem ; 211: 108670, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38703501

RESUMEN

Plants would encounter various biotic and abiotic stresses during the growth and development. WRKY transcription factors (TFs) as plant-specific TFs, play an important role in responding to various adverse circumstances. Despite some advances were achieved in functional studies of WRKY TFs in tea plants, systematic analysis of the involvement of CsWRKY TFs when facing cold, salt, drought stresses and pathogen and insect attack was lacked. In present study, a total of 78 CsWRKY TFs were identified following the genomic and transcript databases. The expression patterns of CsWRKYs in various organs of tea plants and the expression profiles in response to biotic and abiotic stresses were investigated by examining representative RNA-seq data. Moreover, the effects of hormone treatments (SA and MeJA) on the transcription levels of WRKY TFs were also investigated. The phylogenetic tree of CsWRKY TFs from different species indicated the functional diversity of WRKY TFs was not closely related to their protein classification. Concurrently, CsWRKY70-2 TF was identified as a positive regulator in response to drought stress. This study provided solid and valuable information, helping us better understand the functional diversity of CsWRKY TFs, and laid the foundation for further research on the function of key WRKY genes in tea plants.


Asunto(s)
Camellia sinensis , Regulación de la Expresión Génica de las Plantas , Filogenia , Proteínas de Plantas , Estrés Fisiológico , Factores de Transcripción , Camellia sinensis/genética , Camellia sinensis/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Estrés Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Sequías , Genoma de Planta , Ciclopentanos/metabolismo , Ciclopentanos/farmacología , Ácido Salicílico/metabolismo , Ácido Salicílico/farmacología , Oxilipinas/farmacología , Oxilipinas/metabolismo , Acetatos/farmacología
2.
BMC Plant Biol ; 24(1): 455, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38789917

RESUMEN

BACKGROUND: The tea plant (Camellia sinensis (L.) O. Kuntze) is one of the most economically important woody crops. Plastic greenhouse covering cultivation has been widely used in tea areas of northern China. Chlorophyll is not only the crucial pigment for green tea, but also plays an important role in the growth and development of tea plants. Currently, little is known about the effect of plastic greenhouse covering cultivation on chlorophyll in tea leaves. RESULTS: To investigate the effect of plastic greenhouse covering cultivation on chlorophyll in tea leaves, color difference values, chlorophyll contents, gene expression, enzyme activities and photosynthetic parameters were analyzed in our study. Sensory evaluation showed the color of appearance, liquor and infused leaves of greenhouse tea was greener than field tea. Color difference analysis for tea liquor revealed that the value of ∆L, ∆b and b/a of greenhouse tea was significantly higher than field tea. Significant increase in chlorophyll content, intracellular CO2, stomatal conductance, transpiration rate, and net photosynthetic rate was observed in greenhouse tea leaves. The gene expression and activities of chlorophyll-metabolism-related enzymes in tea leaves were also activated by greenhouse covering. CONCLUSION: The higher contents of chlorophyll a, chlorophyll b and total chlorophyll in greenhouse tea samples were primarily due to higher gene expression and activities of chlorophyll-metabolism-related enzymes especially, chlorophyll a synthetase (chlG), pheophorbide a oxygenase (PAO) and chlorophyllide a oxygenase (CAO) in tea leaves covered by greenhouse. In general, our results revealed the molecular basis of chlorophyll metabolism in tea leaves caused by plastic greenhouse covering cultivation, which had great significance in production of greenhouse tea.


Asunto(s)
Camellia sinensis , Clorofila , Hojas de la Planta , Camellia sinensis/genética , Camellia sinensis/enzimología , Camellia sinensis/crecimiento & desarrollo , Camellia sinensis/fisiología , Camellia sinensis/metabolismo , Clorofila/metabolismo , Hojas de la Planta/metabolismo , Hojas de la Planta/genética , Fotosíntesis , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética
3.
Anal Chem ; 2024 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-38343063

RESUMEN

Although super-resolution imaging provides a great opportunity to disclose the structures of living cells at the nanoscale level, resolving the structural details of organelles is highly dependent on the targeting accuracy and photophysical properties of fluorescence trackers. Herein, we report a series of ultrabright and photostable trackers of lysosomal membranes for super-resolution imaging using stimulated emission depletion microscopy (STED). These trackers are composed of lipophilic NIR BODIPY derivatives and ionizable tertiary amines. This structural feature enables accurate targeting of the lysosomal membrane through the formation of transient amphiphilicity driven by the acidity in the lysosome. As a representative, Lyso-700 is applied for STED-based super-resolution imaging of the lysosomal membrane of living macrophages. By use of Lyso-700, the interaction details between lysosomes of macrophages and fungi are visualized. Overall, these trackers display great potential as advanced lysosome trackers and merit further evaluation for lysosome-related studies.

4.
J Am Chem Soc ; 145(51): 28296-28306, 2023 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-38090812

RESUMEN

Atherosclerosis (AS) is the formation of plaques in blood vessels, which leads to serious cardiovascular diseases. Current research has disclosed that the formation of AS plaques is highly related to the foaming of macrophages. However, there is a lack of detailed molecular biological mechanisms. We proposed a "live sensor" by grafting a tetrazine-based ratiometric NO probe within macrophages through metabolic and bio-orthogonal labeling. This "live sensor" was proved to target the AS plaques with a diameter of only tens of micrometers specifically and visualized endogenous NO at two lesion stages in the AS mouse model. The ratiometric signals from the probe confirmed the participation of NO during AS and indicated that the generation of endogenous NO increased significantly as the lesion progressed. Our proposal of this "live sensor" provided a native and smart strategy to target and deliver small molecular probes to the AS plaques at the in vivo level, which can be used as universal platforms for the detection of reactive molecules or microenvironmental factors in AS.


Asunto(s)
Aterosclerosis , Placa Aterosclerótica , Ratones , Animales , Óxido Nítrico/metabolismo , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patología , Macrófagos/metabolismo , Aterosclerosis/metabolismo , Aterosclerosis/patología , Sondas Moleculares/metabolismo
5.
Nat Commun ; 14(1): 7251, 2023 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-37945555

RESUMEN

Multidrug-resistant (MDR) bacteria cause severe clinical infections and a high mortality rate of over 40% in patients with immunodeficiencies. Therefore, more effective, broad-spectrum, and accurate treatment for severe cases of infection is urgently needed. Here, we present an adoptive transfer of macrophages loaded with a near-infrared photosensitizer (Lyso700D) in lysosomes to boost innate immunity and capture and eliminate bacteria through a photodynamic effect. In this design, the macrophages can track and capture bacteria into the lysosomes through innate immunity, thereby delivering the photosensitizer to the bacteria within a single lysosome, maximizing the photodynamic effect and minimizing the side effects. Our results demonstrate that this therapeutic strategy eliminated MDR Staphylococcus aureus (MRSA) and Acinetobacter baumannii (AB) efficiently and cured infected mice in both two models with 100% survival compared to 10% in the control groups. Promisingly, in a rat model of central nervous system bacterial infection, we performed the therapy using bone marrow-divided macrophages and implanted glass fiber to conduct light irradiation through the lumbar cistern. 100% of infected rats survived while none of the control group survived. Our work proposes an efaficient and safe strategy to cure MDR bacterial infections, which may benefit the future clinical treatment of infection.


Asunto(s)
Acinetobacter baumannii , Staphylococcus aureus Resistente a Meticilina , Fotoquimioterapia , Infecciones Estafilocócicas , Humanos , Ratas , Ratones , Animales , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Fotoquimioterapia/métodos , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus , Bacterias , Macrófagos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana Múltiple
6.
BMC Plant Biol ; 23(1): 285, 2023 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-37248487

RESUMEN

BACKGROUND: Taxaceae, is a class of dioecious and evergreen plant with substantial economic and ecology value. At present many phytochemical analyses have been performed in Taxus plants. And various biological constituents have been isolated from various Taxus species. However, the difference of compounds and antioxidant capacity of different tissues of T. media is not clear. RESULTS: In the present study, we investigated the metabolites and antioxidant activity of four tissues of T. media, including T. media bark (TB), T. media fresh leaves (TFL), T. media seeds (TS), T. media aril (TA). In total, 808 compounds, covering 11 subclasses, were identified by using UPLC-MS/MS. Paclitaxel, the most popular anticancer compound, was found to accumulate most in TS, followed by TB, TFL and TA in order. Further analysis found that 70 key differential metabolites with VIP > 1.0 and p < 0.05, covering 8 subclasses, were screened as the key differential metabolites in four tissues. The characteristic compounds of TFL mainly included flavonoids and tanninsis. Alkaloids and phenolic acids were major characteristic compounds of TS and TB respectively. Amino acids and derivatives, organic acids, saccharides and lipids were the major characteristic compounds of TA. Additionally, based on FRAP and ABTS method, TS and TFL exhibited higher antioxidant activity than TB and TA. CONCLUSION: There was significant difference in metabolite content among different tissues of T. media. TFL and TS had higher metabolites and antioxidant capacity than other tissues, indicating that TFL and TS were more suitable for the development and utilization of T. media in foods and drinks.


Asunto(s)
Antioxidantes , Taxus , Antioxidantes/metabolismo , Taxus/metabolismo , Extractos Vegetales/análisis , Cromatografía Liquida , Espectrometría de Masas en Tándem , Metabolómica/métodos , Flavonoides/metabolismo
7.
J Vis Exp ; (193)2023 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-36971432

RESUMEN

Lipid droplets (LDs) are organelles that play an important role in lipid metabolism and neutral lipid storage in cells. They are associated with a variety of metabolic diseases, such as obesity, fatty liver disease, and diabetes. In hepatic cells, the sizes and numbers of LDs are signs of fatty liver disease. Moreover, the oxidative stress reaction, cell autophagy, and apoptosis are often accompanied by changes in the sizes and numbers of LDs. As a result, the dimensions and quantity of LDs are the basis of the current research regarding the mechanism of LD biogenesis. Here, in fatty acid-induced bovine hepatic cells, we describe how to use oil red O to stain LDs and to investigate the sizes and numbers of LDs. The size distribution of LDs is statistically analyzed. The process of small LDs fusing into large LDs is also observed by a live cell imaging system. The current work provides a way to directly observe the size change trend of LDs under different physiological conditions.


Asunto(s)
Gotas Lipídicas , Enfermedad del Hígado Graso no Alcohólico , Animales , Bovinos , Gotas Lipídicas/metabolismo , Hepatocitos/metabolismo , Obesidad/metabolismo , Metabolismo de los Lípidos , Enfermedad del Hígado Graso no Alcohólico/metabolismo
8.
Front Nutr ; 10: 1153983, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36969824

RESUMEN

Matcha has a unique aroma of seaweed-like, which is popular with Chinese consumers. In order to effectively understand and use matcha for drinks and tea products, we roundly analyzed the variation of main quality components of 11 matcha samples from different regions in the Chinese market. Most of matcha samples had lower ratio of tea polyphenols to amino acids (RTA), and the RTA of 9 samples of matcha was less than 10, which is beneficial to the formation of fresh and mellow taste of matcha. The total volatile compounds concentrations by HS-SPME were 1563.59 ~ 2754.09 mg/L, among which terpenoids, esters and alcohols were the top three volatile components. The total volatile compounds concentrations by SAFE was 1009.21 ~ 1661.98 mg/L, among which terpenoids, heterocyclic compounds and esters ranked the top three. The 147 volatile components with high concentration (>1 mg/L) and no difference between samples are the common odorants to the 11 samples of matcha. The 108 distinct odorants had differences among the matcha samples, which were important substances leading to the different aroma characteristics. Hierarchical cluster analysis (HCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) showed that 11 samples of matcha were well clustered according to different components. Japanese matcha (MT, MY, ML, MR, MJ) could be clustered into two categories. The aroma composition of Guizhou matcha (GM1, GM2) was similar to that of Japanese matcha, 45 volatile components (decanal, pyrazine, 3,5-diethyl-2-methyl-, 1-hexadecanol, etc. were its characteristic aroma components. The aroma characteristics of Shandong matcha and Japanese matcha (ML, MR, MJ) were similar, 15 volatile components (γ-terpinene, myrtenol, cis-3-hexenyl valerate, etc.) were its characteristic aroma components. While Jiangsu matcha and Zhejiang matcha have similar aroma characteristics due to 225 characteristic aroma components (coumarin, furan, 2-pentyl-, etc). In short, the difference of volatile components formed the regional flavor characteristics of matcha. This study clarified the compound basis of the flavor difference of matcha from different regions in the Chinese market, and provided a theoretical basis for the selection and application of matcha in drinks and tea products.

9.
J Agric Food Chem ; 71(5): 2377-2389, 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36695193

RESUMEN

Salicylic acid (SA) is an important plant hormone and signal required for establishing resistance to diverse pathogens and plant diseases. The abundant polyphenols in tea plants also defend plants from biotic and abiotic stresses. However, whether exogenous SA would increase the resistance of tea plants to adversity and the relationship between SA and polyphenols are still poorly understood. Here, we carried out SA treatment on tea seedlings and performed transcriptome sequencing. SA treatment inhibited the phenylpropanoid and flavonoid metabolic pathways but promoted the lignin metabolic pathways. The increased accumulation of lignin in tea leaves after treating with SA indicated that lignin might coordinate SA, enhance, and improve plant defense and disease resistance. Simultaneously, an SA-inducible flavonoid glucosyltransferase (CsUGT0554) specifically involved in 7-OH site glycosylation was characterized in vitro. These results provided valuable information about the effects of SA on tea seedlings and the molecular basis for SA-mediated immune responses.


Asunto(s)
Camellia sinensis , Camellia sinensis/metabolismo , Ácido Salicílico/metabolismo , Lignina/metabolismo , Proteínas de Plantas/metabolismo , Flavonoides/metabolismo , Polifenoles/metabolismo , Hojas de la Planta/metabolismo , Té/metabolismo , Regulación de la Expresión Génica de las Plantas
10.
J Sci Food Agric ; 103(2): 657-665, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36054006

RESUMEN

BACKGROUND: Chestnut-like aroma is one of the unique qualities of Chinese green tea and has become an important factor influencing consumer decisions. However, the chemical formation mechanism of chestnut-like aroma during green tea processing remains unclear. In this study, the dynamic changes of key components contributing to chestnut-like aroma and their precursors were analyzed in fresh leaves, fixation leaves, first baking tea leaves, and green tea. RESULTS: The thermal process had an important effect on volatile components in tea leaves, causing a significant decrease of alcohols and esters and a significant increase of ketones, acids, phenols, and sulfur compounds. Furthermore, 31 volatiles were identified as the key odorants responsible for chestnut-like aroma of green tea, including dimethyl sulfide, methyl isobutenyl ketone, 2-methylbutanal, 2,4-dimethylstyrene, d-limonene, methyl 2-methylvalerate, linalool, decanal, longifolene, phenylethyl alcohol, l-α-terpineol, jasmone, and so on. And the majority of these odorants were only formed in the drying stage. Additionally, isoleucine, theanine, methionine, and glucose were found to be involved in the formation of chestnut-like aroma of green tea. CONCLUSION: The drying process played a vital important role in the formation of chestnut-like aroma of green tea. © 2022 Society of Chemical Industry.


Asunto(s)
Camellia sinensis , Compuestos Orgánicos Volátiles , Odorantes/análisis , Té/química , Compuestos Orgánicos Volátiles/química , Cromatografía de Gases y Espectrometría de Masas , Camellia sinensis/química
11.
J Am Chem Soc ; 144(49): 22562-22573, 2022 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-36445324

RESUMEN

Restoring innate apoptosis and simultaneously inhibiting metastasis by a molecular drug is an effective cancer therapeutic approach. Herein, a large rigid and V-shaped NIR-II dye, DUT850, is rationally designed for potential cardiolipin (CL)-targeted chemo-phototheranostic application. DUT850 displays moderate NIR-II fluorescence, excellent photodynamic therapy (PDT) and photothermal therapy (PTT) performance, and ultra-high photostability. More importantly, the unique rigid V-shaped backbone, positive charge, and lipophilicity of DUT850 afford its specific recognition and efficient binding to CL; such an interaction of DUT850-CL induced a spectrum of physiological disruptions, including translocation of cytochrome c, Ca2+ overload, reactive oxygen species burst, and ATP depletion, which not only activated cancer cell apoptosis but also inhibited tumor metastasis both in vitro and in vivo. Furthermore, the tight binding of DUT850-CL improves the phototoxicity of DUT850 toward cancer cells (IC50 as low as 90 nM) under safe 808 nm laser irradiation (330 mW cm-2). Upon encapsulation into bovine serum albumin (BSA), DUT850@BSA exerted a synergetic chemo-PDT-PTT effect on the 4T1 tumor mouse model, eventually leading to solid tumor annihilation and metastasis inhibition, which could be followed in real time with the NIR-II fluorescence of DUT850. This work contributed a promising approach for simultaneously re-engaging cancer cell apoptotic networks and activating the anti-metastasis pathway by targeting a pivotal upstream effector, which will bring a medical boon for inhibition of tumor proliferation and metastasis.


Asunto(s)
Avalanchas , Nanopartículas , Neoplasias , Fotoquimioterapia , Ratones , Animales , Fototerapia , Cardiolipinas , Neoplasias/tratamiento farmacológico , Colorantes Fluorescentes/uso terapéutico , Albúmina Sérica Bovina/química , Apoptosis , Nanopartículas/química , Línea Celular Tumoral
12.
J Am Chem Soc ; 144(48): 21992-21999, 2022 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-36414278

RESUMEN

Sulfoxide-bridged dimeric BODIPYs were developed as a new class of long-wavelength photoconvertible fluorophores. Upon visible-light irradiation, a sulfoxide moiety was released to generate the corresponding α,α-directly linked dimeric BODIPYs. The extrusion of SO from sulfoxides was mainly through an intramolecular fashion involving reactive triplet states. By this photoconversion, not only were more than 100 nm red shifts of absorption and emission maxima (up to 648/714 nm) achieved but also stable products with bright fluorescence were produced with high efficiency. The combination of photoactivation and red-shifted excitation/emission offered optimal contrast and eliminated the interference from biological autofluorescence. More importantly, the in situ products of these visible-light-induced reactions demonstrated ideal single-molecule fluorescence properties in the near-infrared region. Therefore, this new photoconversion could be a powerful photoactivation method achieving super-resolution single-molecule localization imaging in a living cell without using UV illumination and cell-toxic additives.


Asunto(s)
Fotoquímica , Espectroscopía Infrarroja Corta
13.
ACS Nano ; 16(11): 18344-18354, 2022 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-36373972

RESUMEN

The techniques to quantitatively monitor environmental factors surrounding the bacterial outer surface rather than the host's subcellular regions (e.g., lysosomes) should be the key to evaluate bacterial immune escape behavior. We report wild Staphylococcus aureus (SA) and methicillin-resistant Staphylococcus aureus (MRSA) labeled with a fluorescent resonance energy transfer probe, 4SR-L-BDP, on their outer surfaces as smart live sensors to quantify interfacial pH. The dual emission of 4SR-L-BDP affords high sensitivity to pH change in a ratiometric way in the pH range of 4-8 with high precision. Notably, 4SR-L-BDP possesses an anchoring group to fix on the bacterial surface for sensing the microenvironment encountered. Super-resolution imaging clearly demonstrates the specific labeling of bacterial membranes. These live sensors are applied in two-channel ratiometric imaging to dynamically visualize and quantify their interfacial pH changes during infection of macrophages. It is found that the interfacial pH of MRSA is lower by 0.2 units compared to that of SA. Such small but critical difference in pH reflects MRSA's ability to adapt to microenvironmental pH inside macrophages. These labeled bacteria as live sensors are also proven to be practically applicable in mice models with immune deficiency and immune activation.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Ratones , Animales , Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Staphylococcus aureus , Infecciones Estafilocócicas/microbiología , Colorantes Fluorescentes , Concentración de Iones de Hidrógeno
14.
Anal Chem ; 94(45): 15678-15685, 2022 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-36326262

RESUMEN

Nitric oxide (NO), playing crucial roles as a cellular messenger and as a toxic ROS, is highly related to the physiological and pathological states of living systems. The very wide but very uneven distribution of this radical gas in the inhomogeneous biological microenvironment imposes big challenges for specifically detecting its local level in certain subcellular areas, which calls for a long list of NO probes for each target. In order to simplify the syntheses and designs of these probes, herein it is proposed to construct a versatile NO-sensing toolbox based on a bio-orthogonal concept, i.e., inverse electron demand Diels-Alder click reaction between tetrazine and strained alkyne BCN. On the one hand, rhodamine-o-phenylenediamine as the NO-responsive scaffold is coupled with a tetrazine unit to generate a general probe TMR-Tz-NO, which, to our knowledge, is the first case of the tetrazine-coupled analyte-responsive probe. On the other hand, the BCN moiety is connected to different targeting groups, such as TPP, morpholine, and Ac4ManN, targeting to mitochondria, lysosomes, and membranes, respectively. It works well to use TMR-Tz-NO to match with any targetable BCN counterpart in this toolbox to achieve the imaging of NO in the corresponding subcellular area. For example, through metabolism, Ac4ManN-BCN is effectively taken and grows on the cell membranes. The bio-orthogonal reaction between TMR-Tz-NO and Ac4ManN-BCN makes the NO probe anchored to the membrane surface permanently. The zebrafish experiment revealed that this bio-orthogonal pair can track and image the NO produced during inflammation in vivo.


Asunto(s)
Óxido Nítrico , Pez Cebra , Animales , Alquinos , Reacción de Cicloadición , Orgánulos
15.
Foods ; 11(19)2022 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-36230044

RESUMEN

Shandong matcha has the quality characteristics of bright green color, seaweed-like aroma and strong, fresh and brisk taste. In order to identify the characteristic aroma components and clarify the contribution of the grinding process to the aroma of Shandong matcha. Three grades of Shandong matcha and corresponding tencha material were firstly tested with sensory evaluation, and the volatile components were extracted with headspace solid-phase microextraction (HS-SPME) and solvent-assisted flavor evaporation (SAFE) and analyzed using GC-MS. The sensory evaluation results showed that high-grade matcha (M-GS) had prominent seaweed-like, fresh and roasted notes, whereas medium and low-grade matcha (M-G1, M-G2) were gradually coupled with grassy, fatty and high-fired aromas. GC-MS results showed that in the HS-SPME method, heterocyclic compounds (45.84-65.35%) were the highest in Shandong matcha, followed by terpenoids (7.44-16.92%) and esters (6.91-15.27%), while in the safe method, esters were the highest (12.96-24.99%), followed by terpenoids (10.76-25.09%) and heterocyclic compounds (12.12-17.07%). As a whole, the composition of volatile components between M-G1 and M-G2 is relatively close, and there are more differences in volatile components between them and M-GS. The volatile components unique to M-GS were screened using the odor activity value (OAV) evaluation method, with components such as 3-methyl-2-butene-1-thiol, 3-ethyl-Phenol, 2-thiophenemethanethiol, 2,4-undecadienal, (E,E)-2,6-nonadienal, (E,Z)- being evaluated. There were other differentially volatile components, that is, volatile components that coexist in the three grades of matcha, but with different concentrations and proportions. M-G1 and M-G2 contained more volatile substances with high-fired aroma, such as 2-ethyl-3-methyl-pyrazine, coumarin and 5,6,7,8-tetrahydroquinoxaline. The grinding process not only changes the appearance of tencha, but also increases the content of volatile components of matcha as a whole, enhancing the aroma and flavor characteristics of matcha. In this study, the contents of 24 volatile components in matcha were mainly increased, such as benzene, (2,2-dimethoxyethyl)-, cis-7-decen-1-al, safranal and fenchyl acetate. The dual factors of material tencha and matcha grinding technology are indispensable in forming the differences in aroma and flavor of Shandong matcha at different levels.

16.
Foods ; 11(19)2022 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-36230092

RESUMEN

This study investigates the volatile compounds of green tea produced with different leaves from spring, summer, and autumn in high-latitude region. A total of 95 volatile compounds were identified by gas chromatography-mass spectrometry (GC-MS). Spring, summer and autumn green tea contained 68, 72 and 82 volatile compounds, respectively. Principal component analysis (PCA), partial least squares-discrimination analysis (PLS-DA), and hierarchical cluster analysis (HCA) classified the samples and showed the difference. And 32 key characteristic components were screened out based on variable importance in the projection (VIP) values higher than 1.0. The characteristic volatile compounds of spring green tea including 18 components, such as geranylacetone, phenethyl alcohol, geraniol, ß-ionone, jasmone, 1-octen-3-ol and longifolene. 13 components such as 2-methylfuran, indole, 1-octanol, D-limonene and ethanethiol were the key compounds in summer green tea. And 2,4,6-trimethylstyrene was the major differential volatile compounds in autumn green tea. The results increase our knowledge of green tea in different seasons and provide a theoretical basis for production control of green tea.

17.
Chem Commun (Camb) ; 58(72): 10052-10055, 2022 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-35993173

RESUMEN

We proposed to monitor the early stage of alcohol-induced liver injury through quantitatively detecting Golgi viscosity. Therefore, the first Golgi-targeted fluorescent rotor (GA-Vis) was developed. With the aid of GA-Vis, the changes in Golgi viscosity during alcohol-induced liver injury were quantitatively evaluated by fluorescence lifetime imaging in live cells and zebrafish. GA-Vis was qualified as a practical tool for future diagnoses of alcohol-induced liver injury.


Asunto(s)
Enfermedad Hepática Crónica Inducida por Sustancias y Drogas , Colorantes Fluorescentes , Animales , Etanol/toxicidad , Microscopía Fluorescente/métodos , Viscosidad , Pez Cebra
18.
Anal Chem ; 94(32): 11238-11247, 2022 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-35926123

RESUMEN

As a new form of regulated cell death, ferroptosis is closely related to various diseases. To interpret this biological behavior and monitor related pathological processes, it is necessary to develop appropriate detection strategies and tools. Considering that ferroptosis is featured with remarkable lipid peroxidation of various cell membranes, it is logical to detect membranes' structural and environmental changes for the direct assessment of ferroptosis. For this sake, we designed novel polarity-sensitive fluorescent probes Mem-C1C18 and Mem-C18C18, which have superior plasma membrane anchorage, high brightness, and sensitive responses to environmental polarity by changing their fluorescence lifetimes. Mem-C1C18 with much less tendency to aggregate than Mem-C18C18 outperformed the latter in high resolution fluorescence labeling of artificial vesicle membranes and plasma membranes of live cells. Thus, Mem-C1C18 was selected to monitor plasma membranes damaged along ferroptosis process for the first time, in combination with the technique of fluorescence lifetime imaging (FLIM). After treating HeLa cells with Erastin, a typical ferroptosis inducer, the mean fluorescence lifetime of Mem-C1C18 displayed a considerable increase from 3.00 to 4.93 ns, with a 64% increase (corresponding to the polarity parameter Δf increased from 0.213 to 0.232). Therefore, our idea to utilize a probe to quantitate the changes in polarity of plasma membranes proves to be an effective method in the evaluation of the ferroptosis process.


Asunto(s)
Ferroptosis , Colorantes Fluorescentes/química , Células HeLa , Humanos , Microscopía Fluorescente/métodos , Imagen Óptica
19.
ACS Omega ; 7(27): 23634-23642, 2022 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-35847288

RESUMEN

Pyrolysis polygeneration technology has been widely applied due to its wide adaptability to coal types and mild reaction conditions. In this paper, the in situ process test combining pyrolysis and combustion of Pingshuo coal was carried out using a thermogravimetric analyzer and a fluidized-bed reactor. The influence of pyrolysis conditions on the combustion behavior and char structure was studied. The reduction of the pyrolysis temperature and the increase in pyrolysis residence time resulted in a lower burnout temperature of char, thereby improving the combustion characteristics of char. Furthermore, the maximum CO2 release rate reached 2.8 mg/(g·s) during the combustion process. The decrease in the pyrolysis temperature was conducive to the increase of CO2 release mass, suggesting a more complete burning of char. The char combustion process was mainly controlled by the chemical reaction according to the reaction kinetics study. The apparent rate constant of the combustion process increased gradually with the decrease in the pyrolysis temperature of char, and the rate of the combustion reaction increased, which contributed to the enhancement of the combustion performance of the char within the range of 850-950 °C. Meanwhile, the crystal structure inside the char changed significantly after different pyrolysis conditions. However, it had little influence on the molar content of carbon structure, which suggested that the amount of CO2 released was mainly caused by the different resistances of oxygen diffusion to the reaction interface.

20.
Front Microbiol ; 13: 876174, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35495695

RESUMEN

CRISPR-Cas systems acquire heritable defense memory against invading nucleic acids through adaptation. Type III CRISPR-Cas systems have unique and intriguing features of defense and are important in method development for Genetics research. We started to understand the common and unique properties of type III CRISPR-Cas adaptation in recent years. This review summarizes our knowledge regarding CRISPR-Cas adaptation with the emphasis on type III systems and discusses open questions for type III adaptation studies.

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