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1.
Soft Matter ; 20(2): 304-314, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38050746

RESUMO

At low temperatures, colloidal particles with short-range attractive and long-range repulsive interactions can form various periodic microphases in bulk. In this paper, we investigate the self-assembly behaviour of colloids with competing interactions under spherical confinement by conducting molecular dynamics simulations. We find that the cluster, mixture, cylindrical, perforated lamellar and lamellar structures can be obtained, but the details of the ordered structures are different from those in bulk systems. Interestingly, the system tends to form more perforated structures when confined in smaller spheres. The mechanism behind this phenomenon is driven by the relationship between the energy of the ordered structures and the bending of the confinement wall, which is different from the mechanism in copolymer systems.

2.
Compr Rev Food Sci Food Saf ; 22(6): 5063-5085, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37850384

RESUMO

Liubao tea (LBT) is a unique microbial-fermented tea that boasts a long consumption history spanning 1500 years. Through a specific post-fermentation process, LBT crafted from local tea cultivars in Liubao town Guangxi acquires four distinct traits, namely, vibrant redness, thickness, aging aroma, and purity. The intricate transformations that occur during post-fermentation involve oxidation, degradation, methylation, glycosylation, and so forth, laying the substance foundation for the distinctive sensory traits. Additionally, LBT contains multitudinous bioactive compounds, such as ellagic acid, catechins, polysaccharides, and theabrownins, which contributes to the diverse modulation abilities on oxidative stress, metabolic syndromes, organic damage, and microbiota flora. However, research on LBT is currently scattered, and there is an urgent need for a systematical recapitulation of the manufacturing process, the dominant microorganisms during fermentation, the dynamic chemical alterations, the sensory traits, and the underlying health benefits. In this review, current research progresses on the peculiar tea varieties, the traditional and modern process technologies, the substance basis of sensory traits, and the latent bioactivities of LBT were comprehensively summarized. Furthermore, the present challenges and deficiencies that hinder the development of LBT, and the possible orientations and future perspectives were thoroughly discussed. By far, the productivity and quality of LBT remain restricted due to the reliance on labor and experience, as well as the incomplete understanding of the intricate interactions and underlying mechanisms involved in processing, organoleptic quality, and bioactivities. Consequently, further research is urgently warranted to address these gaps.


Assuntos
Camellia sinensis , Catequina , Chá/química , Camellia sinensis/química , China , Catequina/química , Catequina/metabolismo , Estresse Oxidativo
3.
J Food Sci ; 88(12): 5291-5308, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37889079

RESUMO

Oral cavity contains the second largest microbial community in the human body. Due to the highly vascularized feature of mouth, oral microbes could directly access the bloodstream and affect the host healthy systemically. The imbalance of oral microbiota is closely related to various oral and systemic diseases. Green tea extracts (GTE) mainly contain tea polyphenols, alkaloids, amino acid, flavones, and so on, which equipped with excellent anti-inflammatory activities. Previous studies have demonstrated the beneficial effects of GTE on oral health. However, most researches used in vitro models or focused on limited microorganisms. In this study, the regulatory effect of GTE on oral microbiome and the alleviative effect on oral inflammation in vivo were evaluated. The results showed that GTE could efficiently alleviate the inflammations of the tongue, cheek pouch, as well as throat. GTE effectively inhibited the activation of NF-κB through the upregulation of the anti-inflammatory cytokine interleukin (IL)-10, consequently leading to reduced expression of pro-inflammatory cytokines IL-6 and tumor necrosis factor-α. The indexes of spleen and thymus were also elevated by GTE in stomatitis mice. Moreover, GTE promoted the growth of probiotics Lactobacillus and Bacillus, inhibited the reproduction of pathogens Achromobacter, reversing the microbiota disorders in oral cavity. This study not only presents a novel approach for enhancing oral microecology but also facilitates the wider adoption of tea consumption.


Assuntos
Ácido Acético , Chá , Camundongos , Humanos , Animais , Chá/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Inflamação/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/farmacologia , Citocinas
5.
Food Funct ; 14(16): 7400-7412, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37475617

RESUMO

The prevalence of oral health problems is ubiquitous in contemporary society, with particular emphasis placed on the central role of oral flora in mitigating this issue. Both ancient literature and modern research have highlighted the promising application of tea with substantial bioactive properties, particularly dark tea, in preserving and promoting oral health. Liubao tea, a widely consumed dark tea with increasing popularity in recent years, has been reported to possess abundant bioactive constituents, exhibit remarkable antioxidant and anti-inflammatory effects, modulate the flora structure and so on. It may be a promising candidate for addressing oral health problems. In this study, Liubao tea was meticulously extracted, purified and identified, followed by an investigation of its potential to modulate oral microecology by virtue of an acetic acid-induced oral disorder murine model. The results revealed that Liubao tea extract (LTE) application commendably reconstructed the oral mucosal barrier, promoted tissue regeneration and mitigated micro-inflammation. Furthermore, LTE treatment could also ameliorate the oral flora composition by decreasing the abundance of Proteobacteria and increasing the abundance of Firmicutes and Actinobacteria at the phylum level, as well as inhibiting pernicious bacteria such as Streptococcus and Delftia acidovorans. So, it could promote the generation of a beneficial microenvironment and regulate the immune process. Overall, LTE demonstrated remarkable potential in regulating the balance of oral microecology, suggesting that it may represent a promising therapeutic strategy for oral health concerns.

6.
Crit Rev Food Sci Nutr ; : 1-18, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37009836

RESUMO

Yellow tea (YT), a slightly-fermented tea originated from Ming Dynasty with distinctive "Three yellows," mild-sweet smell, and mellow taste attributed to the unique yellowing process. Based on current literature and our previous work, we aim to comprehensively illustrate the key processing procedures, characteristic chemical compounds, health benefits and applications, as well as the interlocking relationships among them. Yellowing is the most vital procedure anchored on the organoleptic quality, characteristic chemical components, and bioactivities of YT, which is influenced by temperature, moisture content, duration, and ventilation conditions. Pheophorbides, carotenoids, thearubigins and theabrownins are the major pigments contributing to the "three yellows" appearance. Alcohols, such as terpinol and nerol, are attributed to the refreshing and sweet aroma of bud and small-leaf YT, while heterocyclics and aromatics forming during roasting result in the crispy rice-like large-leaf YT. Hygrothermal effects and enzymatic reactions during yellowing result in the decline of astringent substances. Meanwhile, multiple bioactive compounds such as catechins, ellagitannins, and vitexin, endow YT with antioxidant, anti-metabolic syndrome, anti-cancer, gut microbiota regulation, and organ injury protection effects. Future studies focusing on the standard yellowing process technology, quality evaluation system, and functional factors and mechanisms, possible orientations, and perspectives are guaranteed.

7.
Food Chem ; 414: 135739, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-36827782

RESUMO

Liu-pao tea (LPT) has unique aroma characteristics, and is a special microbial fermented tea produced using dark raw tea (LPM) as its raw material. In this study, stir bar sorptive extraction (SBSE) combined with gas chromatography-mass spectrometry (GC-MS) was applied to investigate the volatiles of 16 LPTs and 6 LPMs. Moreover, variations in volatile profiles between LPTs and LPMs were explored. Results showed that a total of 132 volatile compounds were identified from LPTs. The volatile fingerprint was constructed with a similarity ranged from 0.85 to 0.99. Furthermore, twenty-six aroma compounds were selected to depict the molecular aroma wheel of LPT. Multivariate statistical analysis revealed that the contents of 24 aroma compounds changed significantly (P < 0.05) when LPMs were processed into LPTs. These results reveal the volatile profiles of LPTs and aroma composition changes during microbial fermentation process, which might provide chemical basis of the aroma quality of LPT.


Assuntos
Odorantes , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas/métodos , Odorantes/análise , Compostos Orgânicos Voláteis/análise , Análise Multivariada , Chá/química
8.
Mitochondrial DNA B Resour ; 6(8): 2425-2426, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34377796

RESUMO

Camellia zhaiana S.X. Yang (Theaceae) is a recently described species reported from Guangxi, China. It was proposed as a critically endangered species according to the IUCN Red List Categories and Criteria. In this study, we report and characterize the complete chloroplast (cp) genome of C. zhaiana using Illumina pair-end sequencing data. This is the first report of a cp genome of a species classified in Camellia section. Longipedicellata. The cp genome of C. zhaiana is 156,627 bp in length and includes a large single-copy region (LSC, 86,196 bp), a small single-copy region (SSC, 18,281 bp), and a pair of inverted repeat regions (IRs, 26,075 bp). The genome contains 135 genes, including 40 tRNA, eight rRNA, and 87 protein-coding genes. Phylogenetic analysis showed a strongly supported sister relationship between C. zhaiana and C. longipedicellata, which is a species classified in sect. Longipedicellata. These data support the previous systematic findings of C. zhaiana and advance the bioinformatics of the genus Camellia.

9.
J Environ Manage ; 270: 110823, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32721298

RESUMO

Barium slag (BS) is a waste residue in the barium salt industrial procedure. Due to its high leaching concentration of Ba2+, BS is classified as a kind of hazardous waste. Industrial waste phosphogypsum (PG) is effective to immobilize barium ion in BS owing to the slightly soluble sulfate included. In this study, two different proportions of PG were selected for mixing with BS to solidify soluble barium ion. The non-hazardous BS samples treated with the proportions of PG (BS-PG1, BS-PG3) were then functionally used for phosphate removal in solution. Batch experiments for removal of phosphate were performed to evaluate the adsorption efficiency of BS-PG1 and BS-PG3. The effect of various factors such as contact time, initial pH, and reaction temperature on sorption performance was investigated. BS-PG1 and BS-PG3 reached adsorption equilibrium in approximately 3h at the initial concentration of 15 mg/L, and BS-PG1 exhibited adsorption capacity of 12.47 mg P/g, higher than that of BS (11.49 mg P/g) under the condition of solid:liquid, 1g:1L, 25 °C, natural pH. The results show that the adsorption processes of phosphates ions onto both BS-PG1 and BS-PG3 fitted well with the pseudo-second-order kinetic model. The Langmuir isothermal model was considered as the appropriate equation for experimental data, showing a maximum adsorption capacity for phosphate up to 13.67 mg P/g and 11.59 mg P/g for BS-PG1 and BS-PG3. In comparison with other adsorbents, BS-PG1 and BS-PG3 could be considered as efficient materials for the removal of phosphate.


Assuntos
Fosfatos , Poluentes Químicos da Água , Adsorção , Bário , Sulfato de Cálcio , Concentração de Íons de Hidrogênio , Cinética , Fósforo
10.
Environ Sci Pollut Res Int ; 27(19): 23871-23879, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32301077

RESUMO

Manganese sulfate residue (MSR) is a by-product derived from the manganese sulfate production process. In this study, an iron hydroxide adsorbent was prepared from MSR using the hydrothermal conversion method. The adsorbent was characterized and used to remove copper(II) ions from aqueous solution. Batch experiments were performed to investigate the adsorption efficiency of copper ions at different contact times, initial concentrations, solution pH levels, and reaction temperatures. Adsorption equilibrium was observed in 3 h, and the best pH was under natural conditions (pH ∼ 5.5). Increasing the initial Cu2+ concentration and reaction temperature can increase the adsorption quantity. The adsorption capacity of iron hydroxide at an initial concentration of 50 mg L-1 was 14.515 mg g-1 Cu(II) under the conditions of a nature pH and room temperature. According to the adsorption data, the pseudo-second-order model can describe the adsorption kinetics of copper ions well, and the Freundlich model provides an excellent fit to the adsorption isotherm. XRD and FTIR were applied to characterize the raw materials and adsorbents to reveal the adsorption mechanism. The results suggest that the adsorbent converted from MSR is a promising material for the removal of Cu(II) in aqueous solutions.


Assuntos
Ferro , Poluentes Químicos da Água , Adsorção , Cobre , Concentração de Íons de Hidrogênio , Cinética , Compostos de Manganês , Soluções , Sulfatos , Termodinâmica
11.
Nutrients ; 10(5)2018 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-29789466

RESUMO

Neurodegenerative disease Alzheimer's disease (AD) is attracting growing concern because of an increasing patient population among the elderly. Tea consumption is considered a natural complementary therapy for neurodegenerative diseases. In this paper, epidemiological studies on the association between tea consumption and the reduced risk of AD are reviewed and the anti-amyloid effects of related bioactivities in tea are summarized. Future challenges regarding the role of tea in preventing AD are also discussed.


Assuntos
Doença de Alzheimer/prevenção & controle , Peptídeos beta-Amiloides/antagonistas & inibidores , Encéfalo/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Extratos Vegetais/uso terapêutico , Chá , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Camellia sinensis/química , Cognição/efeitos dos fármacos , Humanos , Memória/efeitos dos fármacos , Pessoa de Meia-Idade , Degeneração Neural , Fármacos Neuroprotetores/isolamento & purificação , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Prognóstico , Fatores de Proteção , Recomendações Nutricionais , Fatores de Risco
12.
Molecules ; 23(2)2018 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-29462972

RESUMO

(-)-Epigallocatechin gallate (EGCG) has attracted significant research interest due to its health-promoting effects such as antioxidation, anti-inflammation and anti-cancer activities. However, its instability and poor bioavailability have largely limited its efficacy and application. Food-grade materials such as proteins, carbohydrates and lipids show biodegradability, biocompatibility and biofunctionality properties. Food-grade encapsulation systems are usually used to improve the bioavailability of EGCG. In the present paper, we provide an overview of materials and techniques used in encapsulating EGCG, in which the adsorption mechanisms of food-grade systems during in vitro digestion are reviewed. Moreover, the potential challenges and future work using food-grade encapsulates for delivering EGCG are also discussed.


Assuntos
Catequina/análogos & derivados , Composição de Medicamentos , Alimentos , Carboidratos/química , Catequina/química , Humanos , Lipídeos/química , Chá/química
13.
J Thorac Dis ; 9(11): 4599-4606, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29268532

RESUMO

Airway management is a common and key method to maintain and improve external respiration function of patients. Emergency physicians need a more appropriate guide to airway management. We concisely concluded current circumstances of Chinese emergency airway management. Then, we raised four principles: (I) priority to ventilation and oxygenation; (II) evaluation before intubation; (III) higher level of preparation (de-escalation); (IV) simplest (and least potentially harmful) form of intubation. We raised "CHANNEL" flow to direct initial emergency airway management and an algorithm was showed for emergency physicians understanding key points of airway management and further making medical decision. Finally, we introduced pharmacology of airway management.

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