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1.
Molecules ; 29(9)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38731535

RESUMO

Pre-fermentation treatment has an important impact on the color, aroma, taste, and other characteristics of fruit wine. To discover suitable pre-treatment techniques and conditions that yield strawberry wine of excellent quality, the influences of juice fermentation, pulp maceration, thermovinification, and enzymatic hydrolysis pre-treatments on the basic chemical composition, color, antioxidant capacity, and volatile organic compounds in strawberry wines were investigated. The results showed that the color, antioxidant properties, and volatile aroma of strawberry wines fermented with juice were different from those with pulp. Strawberry wines fermented from juice after 50 °C maceration had more desirable qualities, such as less methanol content (72.43 ± 2.14 mg/L) compared with pulp-fermented wines (88.16 ± 7.52 mg/L) and enzymatic maceration wines (136.72 ± 11.5 mg/L); higher total phenolic content (21.78%) and total flavonoid content (13.02%); enhanced DPPH (17.36%) and ABTS (27.55%) free radical scavenging activities; richer essential terpenoids and fatty acid ethyl esters, such as linalool (11.28%), ethyl hexanoate (14.41%), ethyl octanoate (17.12%), ethyl decanoate (32.49%), and ethyl 9-decenoate (60.64%); pleasant floral and fruity notes compared with juice-fermented wines macerated at normal temperatures; and a lighter color. Overall, juice thermovinification at 50 °C is a potential pre-treatment technique to enhance the nutrition and aroma of strawberry wine.


Assuntos
Antioxidantes , Fermentação , Fragaria , Compostos Orgânicos Voláteis , Vinho , Vinho/análise , Compostos Orgânicos Voláteis/análise , Fragaria/química , Antioxidantes/análise , Antioxidantes/química , Odorantes/análise , Fenóis/análise , Flavonoides/análise , Frutas/química , Cor
2.
Zygote ; 28(3): 175-182, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31965957

RESUMO

Stem cells are an immortal cell population capable of self-renewal; they are essential for human development and ageing and are a major focus of research in regenerative medicine. Despite considerable progress in differentiation of stem cells in vitro, culture conditions require further optimization to maximize the potential for multicellular differentiation during expansion. The aim of this study was to develop a feeder-free, serum-free culture method for human embryonic stem cells (hESCs), to establish optimal conditions for hESC proliferation, and to determine the biological characteristics of the resulting hESCs. The H9 hESC line was cultured using a homemade serum-free, feeder-free culture system, and growth was observed. The expression of pluripotency proteins (OCT4, NANOG, SOX2, LIN28, SSEA-3, SSEA-4, TRA-1-60, and TRA-1-81) in hESCs was determined by immunofluorescence and western blotting. The mRNA expression levels of genes encoding nestin, brachyury and α-fetoprotein in differentiated H9 cells were determined by RT-PCR. The newly developed culture system resulted in classical hESC colonies that were round or elliptical in shape, with clear and neat boundaries. The expression of pluripotency proteins was increased, and the genes encoding nestin, brachyury, and α-fetoprotein were expressed in H9 cells, suggesting that the cells maintained in vitro differentiation capacity. Our culture system containing a unique set of components, with animal-derived substances, maintained the self-renewal potential and pluripotency of H9 cells for eight passages. Further optimization of this system may expand the clinical application of hESCs.


Assuntos
Técnicas de Cultura de Células/métodos , Meios de Cultura Livres de Soro/farmacologia , Células-Tronco Embrionárias Humanas/citologia , Células-Tronco Pluripotentes/citologia , Western Blotting , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Células Alimentadoras , Proteínas Fetais/genética , Expressão Gênica , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Proteína Homeobox Nanog/metabolismo , Nestina/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Células-Tronco Pluripotentes/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição SOXB1/metabolismo , Proteínas com Domínio T/genética , alfa-Fetoproteínas/genética
3.
J Food Sci Technol ; 56(5): 2446-2457, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31168127

RESUMO

Hawthorn fruits are rich in nutrients and antioxidant compounds. Dehydration is the major processing and preservation method for hawthorn fruits. The rates of moisture loss; polyphenol, flavonoid and triterpenoid acid contents; and antioxidant activities and their relationships were investigated in hawthorn slices that were dried by four dehydration techniques (microwave drying, solar drying, hot air drying and freeze drying) under different operation conditions. The results showed that both the drying method and the processing parameter affected the antioxidants. Microwave drying and hot air drying at high temperatures (≥ 80 °C) resulted in the degradation of the polyphenols, flavonoids and triterpenoid acids in the hawthorn slices. These antioxidant compounds were best preserved by freeze drying and hot air drying at 60 °C. Epicatechin and chlorogenic acid were the major phenolic compounds identified in this research, and these compounds were significantly affected during processing. The antioxidant activities of the hawthorn fruits were significantly related to the total polyphenol, flavonoid and triterpenoid acid contents. Hot air drying at proper temperatures could be suitable for hawthorn slice dehydration processing that conserves the antioxidant properties of the fruit.

4.
Crit Rev Food Sci Nutr ; 58(14): 2386-2397, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28613932

RESUMO

Quality evaluation of agro-products is quite important because it is the basis for growers, distributers, and consumers. Various novel and emerging nondestructive methods were proposed for quality evaluation of agro-products. The acoustic vibration method is one of the major nondestructive methods for agro-products in pre- and postharvest research and industrial practice. Acoustic vibration characteristics of agro-products can be used for texture evaluation, prediction of optimum eating and harvest ripeness, ripeness classification and defect detection. Generally, there are three parts in the process of acoustic vibration method, including the excitation module, signal acquisition module, and signal-processing module. The impact method and forced method are two excitation methods in the excitation module, and there are contact and noncontact sensors for vibration measurement in the signal acquisition module. Noncontact measurement can meet the requirement of rapid and nondestructive measurement, especially for the on-line detection. However, increasing demand for accurate and cost-effective measurement remains a challenge in the agro-products industry. Comparison of acoustic vibration methods and traditional destructive methods was also discussed, which helps to give a more comprehensive assessment for the acoustic vibration method.


Assuntos
Produtos Agrícolas/normas , Qualidade dos Alimentos , Vibração , Acústica
5.
Fish Shellfish Immunol ; 56: 96-105, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27394968

RESUMO

In the present study, konjac glucomannan (KGM) was degraded by H2O2, and then used trisulfonated sodium amine and HCl, individually, to obtain two kinds of derivatives: oxidized konjac glucomannan sulfates (OKGMS) and acidolysis-oxidized konjac glucomannan (A-OKGM). The effects of two OKGM modified products on the immune parameters and expressions of toll-like receptor 22 (TLR22), myeloid differentiation factor 88 (MyD88) and interferon regulatory factors 7 (IRF7) genes in Schizothorax prenanti were determined. The alternative haemolytic complement (ACH50) activity was found to be significantly increased by the OKGMS diets. The immunoglobulin M (IgM) level was significantly enhanced by the OKGMS diets. The lysozyme activity was significantly increased by both OKGMS and A-OKGM diets. The superoxide dismutase (T-SOD) activity in fish fed with all doses of OKGMS diets was significantly higher than that in fish fed with basal diet. The glutathione peroxidase (GSH-PX) activity in fish fed with 0.8% and 1.6% A-OKGM diets was significantly higher than control group. The malondialdehyde (MDA) level was significantly decreased by both OKGMS and A-OKGM diets. The 0.8% A-OKGM diet significantly up-regulated TLR22 gene expression in the head kidney and spleen. TLR22 gene expression was significantly promoted by all OKGMS diets in the mesonephros and liver. The MyD88 mRNA level in 1.6% A-OKGM group significantly increased in the head kidney. The low dose of OKGMS significantly induced the MyD88 gene expression in the mesonephros, gut and liver, while 0.8% A-OKGM group also showed a significantly enhanced MyD88 mRNA expression in the gut. High dose of OKGMS significantly increased the IRF7 mRNA expression in the mesonephros and spleen. Fish fed with low dose of A-OKGM showed significantly higher expression of IRF7 in the gut and liver. Present study suggested that OKGMS and A-OKGM can act as immunostimulant to improve the immune indexes and up-regulate the immune-related gene expressions.


Assuntos
Cyprinidae , Dieta/veterinária , Suplementos Nutricionais , Proteínas de Peixes/genética , Regulação da Expressão Gênica/imunologia , Imunidade Inata/imunologia , Mananas , Ração Animal/análise , Animais , Cyprinidae/genética , Cyprinidae/imunologia , Cyprinidae/metabolismo , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Proteínas de Peixes/metabolismo , Fator Regulador 7 de Interferon/genética , Fator Regulador 7 de Interferon/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Oxirredução , Distribuição Aleatória , Sulfatos/metabolismo , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo
6.
Molecules ; 20(11): 20460-72, 2015 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-26593891

RESUMO

Peach blossoms were harvested and classified into six developmental stages: (I) bud emerging stage; (II) middle bud stage; (III) large bud stage; (IV) initial-flowering stage; (V) full-flowering stage; and (VI) end-flowering stage. The contents of total phenolics, flavanoids, individual phenolic compounds as well as antioxidant and tyrosinase inhibitory activity of peach blossoms at different developmental stages were investigated. The total phenolic contents varied from 149.80 to 74.80 mg chlorogenic acid equivalents/g dry weight (DW), and the total flavanoid contents ranged from 93.03 to 44.06 mg rutin equivalents/g DW. Both the contents of total phenolics and flavanoids decreased during blossom development. Chlorogenic acid was the predominant component, accounting for 62.08%-71.09% of the total amount of identified phenolic compounds in peach blossom. The antioxidant capacities determined by different assays and tyrosinase inhibitory activity also showed descending patterns during blossom development. Significant correlations were observed between antioxidant capacities with contents of total phenolics and total flavanoids as well as chlorogenic acid, cinnamic acid and kaempferol-3-O-galactoside, while the tyrosinase inhibitory activity had lower correlations with total phenolics and total flavanoids as well as chlorogenic acid, quercetin-3-O-rhamnoside, kaempferol-3-O-galactoside and cinnamic acid. The antioxidant activities of peach blossom seemed to be more dependent on the phenolic compounds than tyrosinase inhibitory activity.


Assuntos
Antioxidantes/química , Inibidores Enzimáticos/química , Flavonoides/química , Flores/química , Fenóis/química , Extratos Vegetais/química , Prunus persica/química , Antioxidantes/farmacologia , Cromatografia Líquida de Alta Pressão , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Concentração Inibidora 50 , Monofenol Mono-Oxigenase/antagonistas & inibidores , Fenóis/farmacologia , Extratos Vegetais/farmacologia
7.
Sci Rep ; 14(1): 20671, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237717

RESUMO

Automated defect detection in electroluminescence (EL) images of photovoltaic (PV) modules on production lines remains a significant challenge, crucial for replacing labor-intensive and costly manual inspections and enhancing production capacity. This paper presents a novel PV defect detection algorithm that leverages the YOLO architecture, integrating an attention mechanism and the Transformer module. We introduce a polarized self-attention mechanism in the feature extraction stage, enabling separate extraction of spatial and semantic features of PV modules, combined with the original input features, to enhance the network's feature representation capabilities. Subsequently, we integrate the proposed CNN Combined Transformer (CCT) module into the model. The CCT module employs the transformer to extract contextual semantic information more effectively, improving detection accuracy. The experimental results demonstrate that the proposed method achieves a 77.9% mAP50 on the PVEL-AD dataset while preserving real-time detection capabilities. This method enhances the mAP50 by 17.2% compared to the baseline, and the mAP50:95 metric exhibits an 8.4% increase over the baseline.

8.
Food Chem ; 464(Pt 1): 141560, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39396467

RESUMO

The study was the first to evaluate the synergistic interaction of luteolin + quercetin, luteolin + 3-O-methylquercetin, and quercetin + 3-O-methylquercetin mixtures on α-glucosidase and the binding mechanisms were explored using both experimental and theoretical approaches. The results showed that three flavonoid mixtures exhibited a mixed type of inhibition and demonstrated the most potent synergistic effects on α-glucosidase inhibition at 6:4 ratio, with interaction index (γ) of 0.85, 0.78 and 0.73, respectively. The three mixtures had a great influence on α-glucosidase secondary structures. Molecular simulation further demonstrated that three flavonoid mixtures formed hydrophobic interactions and hydrogen bonds with amino acid residues at different sites of α-glucosidase. Collectively, luteolin + quercetin, luteolin + 3-O-methylquercetin and quercetin + 3-O-methylquercetin were found to inhibit α-glucosidase in a synergistic manner and can be potentially used for the development of hypoglycemic food products.

9.
Toxicol Lett ; 394: 46-56, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38408587

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are major organic pollutants attached to fine particulate matter in the atmosphere. They induce lung inflammation, asthma, and other lung diseases. Exploring the toxic mechanism of PAHs on lung epithelial cells may provide a theoretical basis for the prevention and treatment of respiratory diseases induced by PAHs. In our study, 16 human bronchial epithelial (16HBE) cells were exposed to different concentrations of gypsum dust, Benzo(a)pyrene (BaP), and BaP-loaded gypsum dust for 24 hours. Gypsum dust loaded with BaP significantly increased the cytotoxicity of 16HBE cells, enhanced the production of lactate dehydrogenase (LDH), interleukin-6 (IL-6) and interleukin-8 (IL-8), induced cell apoptosis, and upregulate the expression of hsa_circ_0008500 (circ_0008500). The mechanism was studied with a BaP-loaded gypsum dust concentration of 1.25 mg/mL. StemRegenin 1 (SR1) pretreat significantly reduced the release of LDH, IL-6, and IL-8 and decreased the protein levels of Ahr、XAP2, C-myc, and p53. Second-generation sequencing indicated that circ_0008500 was highly expressed after 16HBE induced by BaP-loaded gypsum dust. Functional experiments confirmed that circ_0008500 promoted the inflammation and apoptosis of 16HBE cells induced by BaP-loaded gypsum dust by regulating the Ahr signaling pathway. Our study showed that fine particulate matter adsorption of BaP significantly increased the toxic effect of BaP on cells. By activating the Ahr/C-myc pathway, circ_0008500 promoted inflammation and apoptosis of 16HBE cells induced by BaP-loaded gypsum dust.


Assuntos
Benzo(a)pireno , Hidrocarbonetos Policíclicos Aromáticos , Humanos , Benzo(a)pireno/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo , Sulfato de Cálcio/metabolismo , Sulfato de Cálcio/farmacologia , Interleucina-6/genética , Interleucina-6/metabolismo , Células Epiteliais , Inflamação/induzido quimicamente , Inflamação/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poeira , Apoptose , Material Particulado/toxicidade
10.
Oncogene ; 43(29): 2244-2252, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38806619

RESUMO

The combination of programmed cell death protein 1 (PD-1) and cytotoxic T lymphocyte antigen 4 (CTLA-4) antibodies has potential for enhancing clinical efficacy. We described the development and antitumor activity of Z15-0, a bispecific nanobody targeting both the PD-1 and CTLA-4 pathways simultaneously. We designed and optimized the mRNA sequence encoding Z15-0, referred to as Z15-0-2 and through a series of in vitro and in vivo experiments, we established that the optimized Z15-0-2 mRNA sequence significantly increased the expression of the bispecific nanobody. Administration of Z15-0-2 mRNA to tumor-bearing mice led to greater inhibition of tumor growth compared to controls. In aggregate, we introduced a novel bispecific nanobody and have re-engineered it to boost expression of mRNA, representing a new drug development paradigm.


Assuntos
Anticorpos Biespecíficos , Antígeno CTLA-4 , Receptor de Morte Celular Programada 1 , Anticorpos de Domínio Único , Antígeno CTLA-4/antagonistas & inibidores , Antígeno CTLA-4/imunologia , Animais , Camundongos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Humanos , Anticorpos de Domínio Único/farmacologia , Anticorpos de Domínio Único/imunologia , Anticorpos Biespecíficos/farmacologia , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Neoplasias/patologia , Feminino , Ensaios Antitumorais Modelo de Xenoenxerto
11.
J Food Sci ; 88(2): 837-847, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36624616

RESUMO

A new method combining ultraviolet (UV) spectrophotometry and MoO3- x nanosheets was developed for the rapid and accurate determination of ascorbic acid (AA) content in fruit and vegetables in this study. MoO3- x nanosheets were prepared by the liquid exfoliation method using AA as the reducing agent, and the content of AA can be determined by a UV spectrophotometer. Experimental conditions for the MoO3- x nanosheet method, including grinding time, ethanol concentration, sonication time, and water bath temperature were also optimized. The morphology of MoO3- x nanosheets was characterized by atomic force microscope. The results showed that the average thickness of MoO3- x nanosheets was 2.1-5.8 nm. The MoO3- x nanosheets method had a good linearity in the AA concentration range of 0.01-0.05 mg/ml (R2  = 0.9996). The limit of detection was 0.031 µg/ml, and the limit of quantitation was 0.095 µg/ml. The spiked recoveries were in the range of 88.79%-116.76%. The MoO3- x nanosheets method was validated for the determination of AA content in five different fruit and vegetables samples with relative standard deviations less than 2%.


Assuntos
Ácido Ascórbico , Verduras , Ácido Ascórbico/análise , Frutas/química , Espectrofotometria Ultravioleta
12.
Foods ; 12(12)2023 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-37372613

RESUMO

Poor temperature management along a cold chain leads to fruit quality deterioration and loss. In order to determine the threshold value of temperature fluctuation in a cold chain, peach fruits were stored in four different virtual cold chains applying different temperature-time scenarios. Core temperature profiling, the physicochemical qualities, and the activities of the peaches' antioxidant enzymes were monitored during cold storage and shelf life. Abusive temperature management (temperature increased to 20 and 15 °C three times) resulted in a significant increase in a peach's core temperature to the highest temperature measured: 17.6 °C. The ethylene production rate at the end of the shelf life of peaches under these temperatures was 21.03-28.16% higher than the constant-temperature group and accompanied by significantly lower levels of flesh firmness, titratable acid content, total phenol and flavonoid content, and peroxidase (POD) and catalase (CAT) activities (p < 0.05). The results of a principal component analysis (PCA) and heatmap confirmed the results. Limited temperature increases (10 °C) in a cold chain had little impact on the quality of the peaches, while temperature increases higher than 15 °C three times would negatively affect the quality of the peaches significantly. The temperature of a cold chain needs to be controlled precisely to reduce the loss of peaches.

13.
Environ Toxicol Chem ; 42(3): 594-604, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36582152

RESUMO

Atmospheric micro-/nanominerals play an important role in the adsorption, enrichment, and migration of organochlorine pesticides (OCPs). In the present study, the correlations between OCPs and minerals in outdoor atmospheric dustfall were investigated, and the correlations were used to speculate the source of p,p'-(dicofol+dichlorobenzophenone [DBP]), which is the sum of p,p'-dicofol and p,p'-DBP. Atmospheric dustfall samples were collected from 53 sites in the Chengdu-Deyang-Mianyang economic region in the Sichuan basin. In this region, 24 OCPs were analyzed by gas chromatography-tandem mass spectrometry. The average concentration of 24 OCPs was 51.2 ± 27.4 ng/g. The results showed that the concentration of Σ24 OCPs in urban areas was higher than that in suburban areas (p < 0.05). Minerals in atmospheric dustfall were semiquantitatively analyzed by X-ray diffraction. The primary minerals were quartz, calcite, and gypsum. A Spearman correlation analysis of OCPs and minerals showed that low-volatility OCPs could be adsorbed by minerals in atmospheric dustfall. A density functional theory simulation verified that p,p'-(dicofol+DBP) in atmospheric dustfall was primarily derived from the p,p'-dicofol adsorbed by gypsum. Isomeric ratio results suggested that the samples had weathered lindane and chlordane profiles and confirmed that residents in the Sichuan basin used technical dichlorodiphenyltrichloroethane. Finally, the OCPs were evaluated to determine the potential risk of cancer in adults and children from OCP exposure. Exposure to OCPs via atmospheric dustfall was safe for adults. The cancer risk for children exposed to OCPs was slightly lower than the threshold value (10-6 ) under a high dust ingestion rate, which poses a concern. Environ Toxicol Chem 2023;42:594-604. © 2022 SETAC.


Assuntos
Hidrocarbonetos Clorados , Praguicidas , Criança , Humanos , Adsorção , Sulfato de Cálcio/análise , Dicofol/análise , Cromatografia Gasosa-Espectrometria de Massas , Praguicidas/análise , Hidrocarbonetos Clorados/análise , DDT/análise , Medição de Risco , China , Monitoramento Ambiental/métodos
14.
Environ Pollut ; 330: 121789, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37164219

RESUMO

Inorganic mineral particles play an important role in the formation of atmospheric aerosols in the Sichuan Basin. Atmospheric haze formation is accompanied by the phase transition of mineral particles under high humidity and stable climatic conditions. Backward trajectory analysis was used in this study to determine the migration trajectory of atmospheric mineral particles. Furthermore, Positive matrix factorization (PMF) was used to analyze the sources of atmospheric mineral particles. The phase transition mechanisms of atmospheric mineral particles were studied using ion chromatography, inductively coupled plasma emission spectrometry, total organic carbon analysis, X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy coupled with energy dispersive spectrometry, and grand canonical Monte Carlo methods. Three migration and phase transition paths were identified for the mineral particles. Sources of atmospheric mineral particles included combustion, vehicle emissions, industrial emissions, agricultural sources, and mineral dust. The main mineral phases in atmospheric particles, calcite and dolomite, were transformed into gypsum, and muscovite may be transformed into kaolinite. The phase transition of mineral particles seriously affects the formation of aerosols and worsens haze. Typically, along the Nanchong-Suining-Neijiang-Zigong-Yibin path, calcite is converted into gypsum under the influence of man-made inorganic pollution gases, which worsen the haze conditions and cause slight air pollution for 3-5 days. However, along the Guangyuan-Mianyang-Deyang-Chengdu-Meishan-Ya'an path, anthropogenic volatile organic compounds (VOCs) hindered gypsum formation from dolomite. Furthermore, dolomite and VOCs formed stable adsorption systems (system energies from -0.41 to -4.76 eV, long bonds from 0.20 to 0.24 nm). The adsorption system of dolomite and m/p-xylene, with low system energy (-1.46 eV/-1.33 eV) and significant correlation (r2 = 0.991, p < 0.01), was the main cause of haze formation. Consequently, calcite gypsification and dolomite--VOC synergism exacerbated regional haze conditions. This study provides a theoretical reference for the mechanism of aerosol formation in basin climates.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Humanos , Poluentes Atmosféricos/análise , Compostos Orgânicos Voláteis/análise , Sulfato de Cálcio/análise , Estações do Ano , Carbonato de Cálcio/análise , Emissões de Veículos/análise , Aerossóis/análise , Monitoramento Ambiental/métodos , China
15.
Front Nutr ; 9: 892426, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35634373

RESUMO

With the aim to establish a structure-inhibitory activity relationship of flavonoids against dipeptidyl peptidase-4 (DPP-4) and elucidate the interaction mechanisms between them, a pannel of 70 structurally diverse flavonoids was used to evaluate their inhibitory activities against DPP-4, among which myricetin, hyperoside, narcissoside, cyanidin 3-O-glucoside, and isoliquiritigenin showed higher inhibitory activities in a concentration-dependent manner. Structure-activity relationship analysis revealed that introducing hydroxyl groups to C3', C4', and C6 of the flavonoid structure was beneficial to improving the inhibitory efficacy against DPP-4, whereas the hydroxylation at position 3 of ring C in the flavonoid structure was unfavorable for the inhibition. Besides, the methylation of the hydroxyl groups at C3', C4', and C7 of the flavonoid structure tended to lower the inhibitory activity against DPP-4, and the 2,3-double bond and 4-carbonyl group on ring C of the flavonoid structure was essential for the inhibition. Glycosylation affected the inhibitory activity diversely, depending on the structure of flavonoid aglycone, type of glycoside, as well as the position of substitution. Inhibition kinetic analysis suggested that myricetin reversibly inhibited DPP-4 in a non-competitive mode, whereas hyperoside, narcissoside, cyanidin 3-O-glucoside, and isoliquiritigenin all reversibly inhibited DPP-4 in a mixed type. Moreover, the fluorescence quenching analysis indicated that all the five flavonoid compounds could effectively quench the intrinsic fluorescence of DPP-4 by spontaneously binding with it to form an unstable complex. Hydrogen bonds and van der Waals were the predominant forces to maintain the complex of myricetin with DPP-4, and electrostatic forces might play an important role in stabilizing the complexes of the remaining four flavonoids with DPP-4. The binding of the tested flavonoids to DPP-4 could also induce the conformation change of DPP-4 and thus led to inhibition on the enzyme. Molecular docking simulation further ascertained the binding interactions between DPP-4 and the selected five flavonoids, among which hyperoside, narcissoside, cyaniding 3-O-glucoside, and isoliquiritigenin inserted into the active site cavity of DPP-4 and interacted with the key amino acid residues of the active site, whereas the binding site of myricetin was located in a minor cavity close to the active pockets of DPP-4.

16.
Foods ; 12(1)2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36613222

RESUMO

Monitoring of the quality change of cherry tomatoes during storage is very important for the quality control of cherry tomatoes. In this study, the soluble solids content (SSC), reducing sugars (RSs), titratable acids (TAs), ascorbic acid (AA) and lycopene of cherry tomatoes during storage at 0, 4, 10 or 25 °C were measured, and the kinetic models were established. The results showed that the zero-order reaction combined with the Arrhenius kinetic model could be used for the prediction of changes in SS, RS and AA content. The first-order reaction combined with the Arrhenius kinetic model could be used for the prediction of changes in the TA and lycopene content. The volatile compounds of cherry tomatoes were simultaneously determined by the gas chromatography-mass spectrometry (GC-MS) and electronic nose (E-nose). A total of 104 volatile compounds were identified by GC-MS. Orthogonal partial least squares discriminant analysis (OPLS-DA) showed that there were 13 different metabolites among cherry tomatoes with different freshness. The accuracies of Fisher's models based on E-nose for discriminating freshness of cherry tomatoes stored at 0, 4, 10 and 25 °C were 96%, 100%, 92% and 90%, respectively. This study provides a theoretical basis for the quality control of cherry tomatoes during storage.

17.
Chemosphere ; 288(Pt 3): 132659, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34699883

RESUMO

The biosorption and biomineralization behavior of U(VI) by Kocuria rosea with uranium resistance higher than other general microorganisms was investigated in this study. The results showed the obvious effects of initial U(VI) concentration, biomass, time, and especially pH, and presented that U(VI) was immobilized to K. rosea by physical and chemical action. The characterization results for the precipitation proved that U-P minerals with U(VI) (H3OUO2PO4·3H2O, H2(UO2)2(PO4)2·8H2O) or U(IV) (CaU(PO4)2) were dominant, and the crystallization level increased with time. In the process, the phosphorous containing groups, amino, hydroxyl and carboxyl groups played important roles in adsorption of U(VI), and the phosphate groups were crucial in immobilization of uranium, showing the importance of groups containing phosphorus in both biosorption and biomineralization processes. Our findings focus on the biosorption and biomineralization mechanism of U(VI) by K. rosea, emphasize the synergy of physical adsorption and chemical immobilization in the process and formation of U(VI)-P and U(IV)-P minerals, and highlight the significance of phosphorus involvement in the reaction.


Assuntos
Fósforo , Urânio , Adsorção , Biomineralização , Micrococcaceae , Minerais
18.
Biomed Res Int ; 2021: 5368987, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34307653

RESUMO

In the current study, our goal was to obtain a robust model to predict the speed of sound in biodiesel. For this purpose, an extensive databank has been extracted from previously published papers. Then, a Support Vector Machine (SVM) has been optimized by Grey Wolf Optimization (GWO) method to analyze these data and determine the correlation between speed of sound in biodiesel and its related properties including pressure, temperature, molecular weight, and normal melting point. The results were very satisfactory because the values of statistical parameters R 2 and RMSE were obtained 1 and 1.4024, respectively. Here, this is the first time that the sensitivity analysis is used to estimate this target value. This analysis shows that the pressure widely affects the output values with relevancy factor 87.92. Also, our proposed method is highly accurate than other machine learning methods used in papers employed for this objective.


Assuntos
Biocombustíveis , Som , Máquina de Vetores de Suporte , Modelos Teóricos , Análise de Regressão
19.
PLoS One ; 16(12): e0261387, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34914800

RESUMO

Quaternary Red Clay (QRC) is the most common planting soil with low soil fertility and low crop yields in Southeast China, with low soil fertility and low crop yields. Many factors can impact the fertility and utilization efficiency of QRC. Here, we conducted a long-term fertilization experiment from 1984 to 2013. Five fertilization measures were carried out, including non-fertilization group; chemical Fertilizer group; 70% chemical and 30% organic fertilizer group; 50% chemical and 50% organic fertilizer group; 30% chemical and 70% organic fertilizer group. Soil organic matter (OM), total nitrogen (TN), total phosphorus (TP), total potassium (TK), soil microbial biomass carbon (SMBC) and nitrogen (SMBN), and soil enzymes activity were measured to evaluate the changes of soil. In addition, soil microorganisms were determined by high-throughput sequencing technology, and the dominant microbes were screened. The higher the proportion of organic fertilizer was, the higher the soil OM content was. The OM content of the non-fertilization group was the lowest. Similarly, SMBC and SMBN showed a consistent trend with OM content. Illumina sequence results showed that the application of organic fertilizer reduced the relative abundance of Chloroflexi, Acidobacteria and Nitrospirae, but increased Proteobacteria and Actinobacteria. The relative abundance of Acremonium and Mortierella were also greatly increased by different fertilization strategies. However, when high proportion of organic fertilizer was applied, the abundance of Acremonium and Mortierella decreased. Long-term balanced inorganic fertilization (NPK, 60%N:20%P:20%K) can effectively improve the quality and fertility of QRC. The effect of different fertilization strategies on fungi was greater than that on bacteria. The change of soil microorganism also proved the validity of inorganic fertilizer application.


Assuntos
Argila/microbiologia , Fertilizantes/microbiologia , Solo/química , Agricultura/métodos , Biomassa , Carbono/análise , China , Fertilizantes/análise , Nitrogênio/análise , Fósforo/análise , Potássio/análise , Microbiologia do Solo
20.
Food Sci Nutr ; 8(2): 1058-1066, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32148814

RESUMO

Maturity is a key attribute to evaluate the quality and acceptability of fruit products. In this study, the impact method was used for nondestructive measurement of kiwifruit maturity. The fruit was vertically dropped onto an impact plate, and an accelerometer was used to measure the response signal. Then, fruit firmness, soluble solid content (SSC), titratable acidity (TA), and sensory scores were measured to determine the kiwifruit maturity. In addition, different modeling methods were proposed for data analysis. The results showed that the optimized prediction results were obtained by the principal component analysis-back-propagation neural network (PCA-BPNN) method for both quantitative and qualitative analysis. The optimized correlation coefficient between prediction and actual values (r p) and root mean square error of prediction (RESEP) for firmness, SSC, TA, and sensory score were 0.881 (2.359N), 0.641 (1.511 Brix), 0.568 (0.023%), and 0.935 (0.693), respectively. The optimized discriminant accuracy for immature, mature, and overmature kiwifruits was 94.2% and 92.1% for calibration and validation, respectively. Such results indicated the feasibility of the proposed impact method for kiwifruit maturity evaluation.

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