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1.
J Phys Chem Lett ; 14(1): 107-115, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36574224

RESUMO

Kesterite Cu2ZnSn(S,Se)4 (CZTSSe) solar absorbers have attracted intensive investigations for next-generation photovoltaic applications. Here, by using ab initio static and molecular dynamics simulations, we investigated the anion compositional dependence of electron-vibration interaction in CZTSSe materials. We found that the conduction band fluctuates more than the valence band, and as a result, the band gap variation is more sensitive to the change of the former, which can be understood in terms of p-d hybridization in the valence bands. Electron-phonon coupling is smaller in CZTSSe alloy compared to pure S- or Se-containing structures, as evidenced by the smaller fluctuation of excitation energy, and can be attributed to the weaker structural dynamics of the metal-anion bond. Small electron-phonon coupling strength may lead to better charge transport in these materials. We also elucidated the interplay between disordered structures and S/Se stoichiometry through analysis of optical line width. The results highlight the importance of anion composition engineering and provide new insights into the rational design of high-performing kesterite absorbers for solar cells.

2.
Food Chem ; 386: 132762, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35334324

RESUMO

Currently, the increasing incidence of food allergy is considered a major public health and food safety concern. Importantly, food-induced anaphylaxis is an acute, life-threatening, systemic reaction with varied clinical presentations and severity that results from the release of mediators from mast cells and basophils. Many factors are blamed for the increasing incidence of food allergy, including hygiene, microbiota (composition and diversity), inopportune complementary foods (a high-fat diet), and increasing processed food consumption. Studies have shown that different food components, including lipids, sugars, polyphenols, and vitamins, can modify the immunostimulating properties of allergenic proteins and change their bioavailability. Understanding the role of the food components in allergy might improve diagnosis, treatment, and prevention of food allergy. This review considers the role of the dietary components, including lipids, sugars, polyphenols, and vitamins, in the development of food allergy as well as results of mechanistic investigations in in vivo and in vitro models.


Assuntos
Anafilaxia , Hipersensibilidade Alimentar , Alérgenos , Dieta Hiperlipídica , Hipersensibilidade Alimentar/prevenção & controle , Humanos , Lipídeos , Polifenóis , Açúcares , Vitaminas
3.
Mol Nutr Food Res ; 66(10): e2101057, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35286767

RESUMO

Major depressive disorder (MDD) is an enfeebling disease with a lifetime incidence of 20%. While accumulating studies implicate a correlation between the disease and gut microbiota, data show that not every patient responded to probiotic treatments. To comprehensively assess the potential role of probiotics in MDD, this study first summarizes the current pathological hypothesis of the disease from a life-stage perspective, focuses on the potential role of "depression gut microbiota." Currently available managements are then briefly summarized and novel bio-materials having potential therapeutic effects on MDD are also evaluated. To harness the positive effect of probiotics, prebiotics, and postbiotics, clinical evidence and their applications on MDD patients are listed. Factors that may counteract the pre/probiotic applications, such as diet, physiology, gender difference, and use of antibiotics and antidepressants are also discussed. The endocannabinoid (eCBs) system may be promising targets for probiotic therapy. More evidence is needed to demonstrate the hierarchical factors in the complex network driving the disease, and probiotic can be one promising adjunct for patients with MDD.


Assuntos
Transtorno Depressivo Maior , Microbioma Gastrointestinal , Probióticos , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Humanos , Prebióticos , Probióticos/uso terapêutico
4.
Food Res Int ; 137: 109586, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33233194

RESUMO

Residual microorganisms in dairy products are closely related to their quality deterioration and safety. Based on the minimum sterilization conditions required by Grade A Pasteurized Milk Ordinance, this study explored the microbiota present in milk products that were high temperature short time pasteurized at 72, 75, 80, 83, or 85 °C for 15 s, 20 s, and 30 s separately. Based on high-throughput sequencing results, 6 phyla and 18 genera were identified as dominant microbiota. Proteobacteria and Firmicutes were the maior bacteria in phyla, and each comprising more than 50%. Pseudomonas was account for more than 42% of all the genera detected in all samples. Moreover, the changes in flavor substances in pasteurized milk, including 16 free amino acids, 9 fatty acids, and 17 volatile compounds, were detected using principal component and multi factor analyses. The Pearson correlation coefficient analysis identified six bacteria genera as the core functional microbiota that significantly affected the flavor compounds and the safety and quality of pasteurized milk. Interestingly, Pseudomonas, Omithimimicrobium, Cyanobacteria and Corynebacterium had positive correlations with the flavor substances, whereas Streptococcus and Paeniclostridium had significant negative correlations with these substances. The results may help enhance the quality control of dairy products and can be used as indicators of microbial contamination of pasteurized dairy products.


Assuntos
Microbiota , Leite , Animais , Bactérias/genética , Sequenciamento de Nucleotídeos em Larga Escala , Proteobactérias
5.
J Food Drug Anal ; 27(3): 623-631, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31324279

RESUMO

Trillions of microbes have evolved with and continue to live on human beings. With the rapid advances in tools and technology in recent years, new knowledge and insight in cross-talk between the microbes and their hosts have gained. It is the aim of this work to critically review and summarize recent literature reports on the role of microbiota and mechanisms involved in the progress and development of major human diseases, which include obesity, hypertension, cardiovascular disease, diabetes, cancer, Inflammatory Bowel Disease (IBD), gout, depression and arthritis, as well as infant health and longevity.


Assuntos
Microbioma Gastrointestinal , Saúde do Lactente , Neoplasias/metabolismo , Artrite/metabolismo , Doenças Cardiovasculares/metabolismo , Depressão/metabolismo , Diabetes Mellitus/metabolismo , Gota/metabolismo , Humanos , Hipertensão/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Obesidade/metabolismo
6.
Zhongguo Zhong Yao Za Zhi ; 44(13): 2799-2805, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31359693

RESUMO

To establish and validate the design space of the Digeda-4 flavored decoction( DGD-4D) extraction process by using the quality by design( Qb D) concept. With DGD-4D decoction pieces as a model drug,with the transfer rate of aesculin,picroside I,picroside Ⅱ,geniposide and the yield of extract as critical quality attributes( CQAs),the single factor experiment design was used to determine the level of each factor; the Plackett-Burman experiment design was used to select the critical process parameters( CPPs);and the Box-Behnken experiment design was used to optimize the extraction process. The design space of the DGD-4D extraction process was established,and finally,four experimental points were selected to verify the established model. The single factor experiment determined the levels of each factor,including soaking time 60 min and 30 min,water adding volume 12 times and 8 times,extraction time 90 min and 30 min,number of extraction times 3 times and 1 time,as well as extraction temperature 100 ℃ and 90 ℃.By Plackett-Burman experimental design,the DGD-4D water addition,extraction time and number of extraction times were determined to be CPPs. The Box-Behnken experimental variance analysis showed that P of the regression model was less than 0. 01 and the misstated value was more than 0. 01,indicating that the model had good predictive ability,and the operation space of CPPs in the DGD-4D extraction process was determined as follows: the amount of water addition was 10-12 times; extraction time 50-80 min; and number of extraction times was 3 times. The design space of DGD-4D extraction process based on the concept of Qb D is conducive to improving the stability of product quality and laying a foundation for the future development of DGD-4D.


Assuntos
Química Farmacêutica/métodos , Medicamentos de Ervas Chinesas/química , Projetos de Pesquisa
7.
Zhongguo Zhong Yao Za Zhi ; 43(19): 3962-3969, 2018 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-30453724

RESUMO

To establish the high performance liquid chromatography (HPLC) fingerprint for Digeda-4 decoction (DGD-4D), determine the contents of aesculetin, geniposide, picroside Ⅰ, picroside Ⅱ and ellagicacid in DGD-4D, and provide the scientific foundation for quality control of DGD-4D. The analysis was performed on Diamonsil(2) C18 (4.6 mm×250 mm,5 µm) column, with methanol-0.1% phosphoric acid aqueous solution as mobile phase for gradient elution. The flow rate was 1.0 mL·min⁻¹; injection size was 10 µL; temperature was maintained at 30 °C, and the detection wavelength was set at 254 nm. The common mode of DGD-4D HPLC fingerprint was established, and the hidden information was analyzed by Chemometrics. Chromatographic peaks for DGD-4D were identified by HPLC and quantitative analysis was conducted for characteristic peaks. There were 17 common peaks in the fingerprints and the similarity of the fingerprints was over 0.9 in all 15 batches. The samples were broadly divided into four kinds by principal component analysis and clustering analysis. Four marker compounds were verified by partial least squares discriminant analysis, and No. 9, 12 and 14 peaks were identified as geniposide, picroside Ⅱ, and picroside Ⅰ respectively. The average recoveries were in the range of 95.91%-97.31%. The HPLC fingerprint method for content determination is reliable, accurate, rapid, simple, and reproducible, and can be used as one of the effective methods to control the quality of DGD-4D.


Assuntos
Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/normas , Cromatografia Líquida de Alta Pressão , Cinamatos , Glucosídeos Iridoides , Iridoides , Metanol , Análise de Componente Principal , Controle de Qualidade
8.
Langmuir ; 30(1): 440-6, 2014 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-24369065

RESUMO

Palladium (Pd) nanocrystals have been synthesized by using formic acid as the reducing agent at room temperature. When the concentration of formic acid was increased continuously, the size of Pd nanocrystals first decreased to a minimum and then increased slightly again. The products have been investigated by a series of techniques, including X-ray diffraction, high-resolution transmission electron microscopy (HRTEM), UV-vis absorption, and electrochemical measurements. The formation of Pd nanocrystals is proposed to be closely related to the dynamical imbalance of the growth and dissolution rate of Pd nanocrystals associated with the adsorption of formate ions onto the surface of the intermediates. It is found that small Pd nanocrystals showed blue-shifted adsorption peaks compared with large ones. Pd nanocrystals with the smallest size display the highest electrocatalytic activity for the electrooxidation of formic acid and ethanol on the basis of cyclic voltammetry and chronoamperometric data. It is suggested that both the electrochemical active surface area and the small size effect are the key roles in determining the electrocatalytic performances of Pd nanocrystals. A "dissolution-deposition-aggregation" process is proposed to explain the variation of the electrocatalytic activity during the electrocatalysis according to the HRTEM characterization.


Assuntos
Técnicas Eletroquímicas , Formiatos/química , Nanopartículas Metálicas/química , Paládio/química , Catálise , Tamanho da Partícula , Propriedades de Superfície
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