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1.
PLoS One ; 19(2): e0296871, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38319932

RESUMO

The Coronavirus Disease 2019 (COVID-19) pandemic has induced a critical supply of personal protective equipment (PPE) especially N95 respirators. Utilizing respirator decontamination procedures to reduce the pathogen load of a contaminated N95 respirator can be a viable solution for reuse purposes. In this study, the efficiency of a novel hybrid respirator decontamination method of ultraviolet germicidal irradiation (UVGI) which utilizes ultraviolet-C (UV-C) rays coupled with microwave-generated steam (MGS) against feline coronavirus (FCoV) was evaluated. The contaminated 3M 1860 respirator pieces were treated with three treatments (UVGI-only, MGS-only, and Hybrid-UVGI + MGS) with variable time. The virucidal activity was evaluated using the TCID50 method. The comparison of decontamination efficiency of the treatments indicated that the hybrid method achieved at least a pathogen log reduction of 4 logs, faster than MGS and UVGI. These data recommend that the proposed hybrid decontamination system is more effective comparatively in achieving pathogen log reduction of 4 logs.


Assuntos
Respiradores N95 , Vapor , Micro-Ondas , Descontaminação/métodos , Reutilização de Equipamento , Raios Ultravioleta , Pandemias
2.
Int J Food Microbiol ; 413: 110592, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38308878

RESUMO

Raw almonds have been associated with Salmonella outbreaks and multiple recalls related to Listeria monocytogenes contamination. While steam treatment has been approved for pasteurizing both conventional and organic whole almonds, there is limited understanding of how water activity (aw) influences the effectiveness of steam treatments in decontaminating almonds. Hence, this study aimed to assess and compare the efficacy of steam treatments against Listeria innocua and Enterococcus faecium NRRL B-2354, the known non-pathogenic surrogates, on almonds. It also sought to investigate the impact of almond's aw on bacterial resistance during steam treatments. Almond kernels were inoculated with ~8 log10 CFU/g of either E. faecium or L. innocua and equilibrated to aw 0.25 or 0.45 before being subjected to steam treatments at temperatures of 100-135 °C. Our results revealed that L. innocua exhibited lower resistance to steam compared to E. faecium, with 1.2-2.6 log10 CFU/g reductions for L. innocua and 1.0-2.0 log10 CFU/g reductions for E. faecium when the surface temperature of almonds reached 100-130 °C, depending on the aw of the almonds. The obtained DL. innocua, 100-130°C-values were 2.0-16.6 s, and DE. faecium, 100-130°C-values were 4.0-21.8 s, depending on the aw of almonds. In general, elevating steam temperatures and almond aw decreased the tolerance of L. innocua and E. faecium during steam inactivation. In addition, the z-values indicated that E. faecium on almonds was less sensitive to change in steam temperature compared to L. innocua, especially at lower aw. The zL. innocua-values were 36.6 °C and 35.7 °C, while zE. faecium-values were 48.9 °C and 42.7 °C in almonds with aw 0.25 and 0.45, respectively. Results from this study suggest that steam treatments serve as effective interventions for controlling pathogen contaminations in raw almonds.


Assuntos
Enterococcus faecium , Listeria , Prunus dulcis , Vapor , Água/análise , Enterococcus faecium/fisiologia , Contagem de Colônia Microbiana , Microbiologia de Alimentos
3.
Molecules ; 29(3)2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38338369

RESUMO

Panax quinquefolius (PQ) has been widely used in traditional Chinese medicine and functional food. Ginsenosides are the important functional components of PQ. The ginsenosides' diversity is deeply affected by the processing conditions. The ginsenosides in the steamed PQ have been not well-characterized yet because of the complexity of their structure. In the study, the comprehensive investigation of ginsenosides was performed on the steamed PQ with different steaming times and temperatures by UPLC-Q-TOF-MS. Based on the molecular weight, retention time and characterized fragment ions, 175 ginsenosides were unambiguously identified or tentatively characterized, including 45 protopanaxatriol type, 49 protopanaxadiol type, 19 octillol type, 6 oleanolic acid type ginsenosides, and 56 other ginsenosides. Ten new ginsenosides and three new aglycones were discovered in the steamed PQ samples through searching the database of CAS SciFindern. Principal component analysis showed the significant influence on the chemical components of PQ through different processing conditions. The steaming temperature was found to promote the transformation of ginsenosides more than the steaming time. The protoginsenosides were found to transform into the rare ginsenosides by elimination reactions. The malonyl ginsenosides were degraded into acetyl ginsenosides, and then degraded into neutral ginsenosides. The sugar chain experienced degradation, with position changes and configuration inversions. Furthermore, 20 (S/R)-ginsenoside Rh1, Rh2, Rg2, and Rh12 were found to transform from the S-configuration to the R-configuration significantly. This study could present a comprehensive ginsenosides profile of PQ with different steaming conditions, and provide technical support for the development and utilization of PQ.


Assuntos
Ginsenosídeos , Panax , Ginsenosídeos/química , Panax/química , Cromatografia Líquida , Espectrometria de Massas em Tandem , Vapor , Cromatografia Líquida de Alta Pressão
4.
Food Res Int ; 180: 114071, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38395575

RESUMO

Textured Soy Proteins (TSPs) have been employed as building blocks in various food processes, but their availability remains limited. In this research, influence of Steam Explosion (SE) with pressure ranges (0, 0.5, 1.0, 1.5 MPa) on the structure and in vitro digestibility of TSPs was investigated. The results showed that 0.5 and 1.0 MPa significantly increased the relative content of ß-sheets and decreased the relative content of α-helices and ß-turns. Correlation analysis revealed that the structural changes made the TSP brittle, with lower thermal stability and resistance to digestion. Moreover, SE decreased the degree of hydrolysis of TSPs in the gastric stage, with the lowest degree observed for the TSP at 0.5 MPa. However, in the intestinal phase, 1.0 and 1.5 MPa significantly increased the hydrolysis degree. These findings provide a better understanding of the SE pressure-modulated quality characteristics of TSPs and suggest the processing potential of modified TSPs as functional ingredients.


Assuntos
Proteínas de Soja , Vapor , Nutrientes , Cinética , Digestão
5.
Europace ; 26(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38367008

RESUMO

AIMS: Failure of radiofrequency (RF) ablation of ventricular arrhythmias is often due to inadequate lesion size. Irrigated RF ablation with half-normal saline (HNS) has the potential to increase lesion size and reduce sodium delivery to the patient if the same volume of RF irrigant were used for normal saline (NS) and HNS but could increase risks related to steam pops and lesion size. This study aims to assess periprocedural complications and acute ablation outcome of ventricular arrhythmias ablation with HNS. METHODS AND RESULTS: Prospective assessment of outcomes was performed in 1024 endocardial and/or epicardial RF ablation procedures in 935 consecutive patients (median age 64 years, 71.2% men, 73.4% cardiomyopathy, 47.2% sustained ventricular tachycardia). Half-normal saline was selected at the discretion of the treating physician. Radiofrequency ablation power was generally titrated to a ≤15â€…Ω impedance fall with intracardiac echocardiography monitoring. Half-normal saline was used in 900 (87.9%) and NS in 124 (12.1%) procedures. Any adverse event within 30 days occurred in 13.0% of patients treated with HNS RF ablation including 4 (0.4%) strokes/transient ischaemic attacks and 34 (3.8%) pericardial effusions requiring treatment (mostly related to epicardial access). Two steam pops with perforation required surgical repair (0.2%). Patients who received NS irrigation had less severe disease and arrhythmias. In multivariable models, adverse events and acute success of the procedure were not related to the type of irrigation. CONCLUSION: Half-normal saline irrigation RF ablation with power guided by impedance fall and intracardiac echocardiography has an acceptable rate of complications and acute ablation success while administering half of the saline load expected for NS irrigation.


Assuntos
Ablação por Cateter , Ablação por Radiofrequência , Taquicardia Ventricular , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Solução Salina/efeitos adversos , Vapor , Estudos Prospectivos , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/cirurgia , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Taquicardia Ventricular/cirurgia , Irrigação Terapêutica/efeitos adversos
6.
Int J Mol Sci ; 25(4)2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38397059

RESUMO

This study explores the impact of plasma treatment on Lavandin Grosso flowers and its influence on the extraction of essential oils (EOs) via hydrodistillation. Short plasma treatment times enhance the yield of EO extraction from 3.19% in untreated samples to 3.44%, corresponding to 1 min of plasma treatment, while longer treatment times (10 min) show diminishing returns to 3.07% of yield extraction. Chemical characterization (GC/MS and ATR-FTIR) indicates that plasma treatments do not significantly alter the chemical composition of the extracted EOs, preserving their aromatic qualities. Investigations into plasma-surface interactions reveal changes at the nanometer level, with XPS confirming alterations in the surface chemistry of Lavandin Grosso flowers by reducing surface carbon and increasing oxygen content, ultimately resulting in an increased presence of hydrophilic groups. The presence of hydrophilic groups enhances the interaction between the surface membrane of the glandular trichomes on Lavandin Grosso flowers and water vapor, consequently increasing the extraction of EOs. Furthermore, microscopic SEM examinations demonstrate that plasma treatments do not affect the morphology of glandular trichomes, emphasizing that surface modifications primarily occur at the nanoscale. This study underscores the potential of plasma technology as a tool to enhance EO yields from botanical sources while maintaining their chemical integrity.


Assuntos
Óleos Voláteis , Óleos Voláteis/química , Cromatografia Gasosa-Espectrometria de Massas , Flores/química , Vapor , Tecnologia
7.
Environ Sci Technol ; 58(8): 3985-3996, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38357760

RESUMO

Achieving no or low polychlorinated byproduct selectivity is essential for the chlorinated volatile organic compounds (CVOCs) degradation, and the positive roles of water vapor may contribute to this goal. Herein, the oxidation behaviors of chlorobenzene over typical Mn-based catalysts (MnO2 and acid-modified MnO2) under dry and humid conditions were fully explored. The results showed that the presence of water vapor significantly facilitates the deep mineralization of chlorobenzene and restrains the formation of Cl2 and dichlorobenzene. This remarkable water vapor-promoting effect was conferred by the MnO2 substrate, which could suitably synergize with the postconstructed acidic sites, leading to good activity, stability, and desirable product distribution of acid-modified MnO2 catalysts under humid conditions. A series of experiments including isotope-traced (D2O and H218O) CB-TPO provided complete insights into the direct involvement of water molecules in chlorobenzene oxidation reaction and attributed the root cause of the water vapor-promoting effect to the proton-rich environment and highly reactive water-source oxygen species rather than to the commonly assumed cleaning effect or hydrogen proton transfer processes (generation of active OOH). This work demonstrates the application potential of Mn-based catalysts in CVOCs elimination under practical application conditions (containing water vapor) and provides the guidance for the development of superior industrial catalysts.


Assuntos
Óxidos , Vapor , Óxidos/química , Compostos de Manganês , Prótons , Catálise , Clorobenzenos/química
8.
World J Urol ; 42(1): 60, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38280069

RESUMO

PURPOSE: In recent years, water vapor thermal therapy (WVTT) has spread as minimally invasive technique in lower urinary tract symptoms due to benign prostatic hyperplasia treatment. Even if its safety and feasibility have been largely proved in young men, nobody has proved the same feasibility and safety in the elderly (men older than 75 years old). Our aim is to compare WVTT safety outcomes in men older than 75 with younger men. METHODS: We prospectively collected data on men who underwent water vapor thermal therapy from 2019. We compared data on operative time, number of injections, intra-operative and post-operative complications, reinterventions rate. RESULTS: We enrolled 426 patients; among these, 60 were older than 75 years old, 366 were younger. Our cohorts of patients had similar results in terms of intra-operative and post-operative complications. Operative time accounts about 11 min for both groups (p = 0.535), total number of injections was seven for young men and eight for elderly (p = 0.314). We found no intra-operative complications in elderly men group and only one in the younger group (p = 0.678), while five younger men underwent clot retention, and two elderly men experienced this complication (p = 0.239). Only one transfusion occurred in the elderly group. No differences between groups occurred in terms of length of stay, post-operative urinary retention and reintervention rate, while catheterization time was longer in the elderly men. CONCLUSION: WVTT is a safe procedure in elderly patients with comparable intra-operative and post-operative complication rate in comparison with younger patients.


Assuntos
Hipertermia Induzida , Sintomas do Trato Urinário Inferior , Hiperplasia Prostática , Masculino , Idoso , Humanos , Vapor , Idoso Fragilizado , Hiperplasia Prostática/complicações , Hipertermia Induzida/métodos , Itália , Sintomas do Trato Urinário Inferior/etiologia , Resultado do Tratamento
9.
Carbohydr Polym ; 327: 121669, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38171660

RESUMO

Steamed Polygonatum cyrtonema has been commonly used clinically for its gaining effect, whose main active ingredient is a polysaccharide. A water-soluble polysaccharide named PSP-W-1 was isolated from steamed Polygonatum cyrtonema. PSP-W-1 was characterized as a galactan having a backbone consisting predominately of 1,4-ß-linked Galp branched at the C-6 position by T-ß-linked Galp with a molecular weight of 14.4 kDa. PSP-W-1 could inhibit the overproduction of inflammatory factors and inflammatory mediators (iNOS, IL-6, COX-2) in dextran sodium sulfate-induced colitis mice. Oral administration of PSP-W-1 dramatically alleviated colonic pathological damage, repaired the intestinal barrier (occludin and ZO-1) and regulated the intestinal microbiota by increasing the abundance of norank_f_Muribaculaceae, Lactobacillus and norank_f_norank_o_Clostridia UCG-014, while decreasing the abundance of Bacteroides and Escherichia-Shigella to alleviate colitis symptoms. Overall, our findings suggest that PSP-W-1 might be a therapeutic option for both the prevention and treatment of colitis.


Assuntos
Colite , Microbioma Gastrointestinal , Polygonatum , Animais , Camundongos , Colite/induzido quimicamente , Colite/tratamento farmacológico , Intestinos , Vapor , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Colo , Sulfato de Dextrana , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças
10.
Food Chem ; 441: 138397, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38219363

RESUMO

Fat reduction due to heating or cooking is an important issue in a healthy diet. In the current study, pork subcutaneous back fat was treated via microwave heating (MH) within 10-90 s and roasting - steam heating (RSH) within 2-30 min and their dynamic changes of individual adipocytes were explored by using vesicles as a bio-membrane model. The result showed that MH and RSH significantly increased fat loss (P < 0.05), with the maximum losses being 74.1 % and 65.6 %, respectively. The mechanical strength of connective tissue decreased and then increased slightly. The microstructure demonstrated that MH and RSH treatments facilitated a large outflow of fat, showing that the particle size of the vesicle and individual adipocytes increased and then decreased. It is thus feasible to study the dynamic changes of individual adipocytes in regulating fat reduction using cell membrane simulation.


Assuntos
Carne de Porco , Carne Vermelha , Animais , Suínos , Vapor , Micro-Ondas , Calefação , Culinária , Membrana Celular
11.
Bioresour Technol ; 394: 130290, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38218409

RESUMO

The presented research results the gasification process of biomass waste (brewery spend grain, wheat straw, hay, pine sawdust). Experimental investigations focused on determining the influence of gasification agent (CO2, steam, and steam and CO2 mixture) and the presence of a solid catalyst (MgO∙CaO, TiO2, CuO and SrO). Investigations were performed towards syngas production. A wide range of analyses and instrumental methods were used to determine the properties of gasification process products, including: GC, TGA, FTIR, SEM, BET. The main component of syngas obtained produced in atmosphere CO2 and steam mixture was hydrogen. The H2 concentration increased from 20% up to 44% in case of brewery spend grain. The presence of the catalyst in the gasification process favoured the tar cracking reaction. The amount of tar was reduced by more than 17% in case of brewery spend grain. As well as syngas composition was enriched with CH4, H2 and CO concentration.


Assuntos
Gases , Vapor , Biomassa , Dióxido de Carbono , Hidrogênio
12.
Mol Pharm ; 21(2): 704-717, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38194618

RESUMO

Monoclonal antibodies (mAbs) are active components of therapeutic formulations that interact with the water-vapor interface during manufacturing, storage, and administration. Surface adsorption has been demonstrated to mediate antibody aggregation, which leads to a loss of therapeutic efficacy. Controlling mAb adsorption at interfaces requires a deep understanding of the microscopic processes that lead to adsorption and identification of the protein regions that drive mAb surface activity. Here, we report all-atom molecular dynamics (MD) simulations of the adsorption behavior of a full IgG1-type antibody at the water/vapor interface. We demonstrate that small local changes in the protein structure play a crucial role in promoting adsorption. Also, interfacial adsorption triggers structural changes in the antibody, potentially contributing to the further enhancement of surface activity. Moreover, we identify key amino acid sequences that determine the adsorption of antibodies at the water-air interface and outline strategies to control the surface activity of these important therapeutic proteins.


Assuntos
Anticorpos Monoclonais , Vapor , Anticorpos Monoclonais/química , Adsorção , Água/química , Composição de Medicamentos
13.
J Environ Manage ; 352: 119967, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38237332

RESUMO

Globally waste incineration is becoming the predominant treatment method of solid waste. The largest fraction of solid residue of this process is incineration bottom ash (IBA) requiring further treatment before applications such as in the construction industry become feasible. In this study, vitrification of IBA was conducted in a demonstration-scale high-temperature slagging gasification plant fueled with MSW and biomass charcoal as a green auxiliary fuel. High IBA co-feeding rates of up to 491 kg/h (equivalent to 107% of MSW feeding rate) were achieved during the trials. A highly leaching-resistant slag immobilizing heavy metals in the glass-like amorphous structure and recyclable iron-rich metal granules were generated in the process. The heavy metal migration into the solid by-product fractions depended on the IBA feeding rates and process conditions such as cold cap temperature, charcoal-to-ash ratio, and gasifier temperature profile. Slaked lime and activated carbon powder were used in a dry flue gas treatment and stack gas emissions were kept well below Singapore's regulatory limits. Steam from the hot flue gas was generated in a boiler to drive a steam turbine. The application of biomass charcoal instead of fossil fuels or electricity lead to a lower carbon footprint compared to alternative vitrification technologies. The overall results reveal promising application of high temperature slagging gasification process for commercial-scale vitrification of IBA.


Assuntos
Metais Pesados , Eliminação de Resíduos , Cinza de Carvão/química , Vapor , Pegada de Carbono , Carvão Vegetal , Vitrificação , Incineração/métodos , Metais Pesados/química , Resíduos Sólidos
14.
Food Chem ; 441: 138324, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38176145

RESUMO

To develop the application of wheat bran and improve the nutrition and anti-staling capacity of Chinese steamed bread (CSB), oleic acid-esterified wheat bran (OWB) was prepared by esterification of wheat bran with oleic acid, and its physicochemical properties, structure, and quality improvement for CSB during refrigerated storage were investigated. The hydrophilic-lipophilic balance value of OWB was 16.0, the maximum degree of substitution was 0.146, and its emulsifying capacity was similar to that of glycerol monostearate. The starch gelatinization degree of CSB containing 3 % OWB and the control decreased by 19.55 % and 27.12 % within 7 days of refrigerated storage, respectively, while the hardness of CSB with OWB was lower than that with wheat bran. OWB inhibited starch recrystallization and increased bound water in the corresponding CSB, which effectively delayed starch retrogradation. OWB had a positive emulsifying capacity and showed potential as a functional material for preventing retrogradation of starch-based foods.


Assuntos
Pão , Fibras na Dieta , Pão/análise , Fibras na Dieta/análise , Melhoria de Qualidade , Ácido Oleico , Amido/química , Vapor , China
15.
Bioresour Technol ; 394: 130293, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38184088

RESUMO

The effects of three catalysts, namely Ni/γ-Al2O3, Fe/γ-Al2O3, and Mg/γ-Al2O3, on the three-phase products of liquor-industry waste pyrolysis were investigated in this study. Results indicated that the catalytic performance of Ni/γ-Al2O3 outperformed those of Fe/γ-Al2O3 and Mg/γ-Al2O3 significantly. The application of Ni/γ-Al2O3 facilitated the reformation of pyrolysis volatiles, leading to increased yields of H2 (174.1 mL/g), CH4 (80.7 mL/g), and CO (88.2 mL/g) by 980.00 %, 133.24 %, and 83.37 %, respectively. compared to catalyst-free conditions. The Ni/γ-Al2O3 also increased the low-level calorific value of biogas by 109.3 % compared to that under non-catalyst conditions. Moreover, Ni/γ-Al2O3 enhanced the relative concentrations of hydrocarbons in tar by 23.15 % while reducing the relative concentrations of O-species by 15.73 % compared to catalyst-free conditions through induced deoxygenation, decarboxylation, decarbonylation reactions as well as efficient steam reforming processes for tar and syngas upgrading purposes. Thus, incorporating Ni/γ-Al2O3 into the pyrolysis process represents a renewable approach for waste-to-energy conversion.


Assuntos
Pirólise , Vapor , Catálise
16.
Int J Biol Macromol ; 259(Pt 1): 129159, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38181905

RESUMO

Skin tissue is damaged by factors such as burns, physical injuries and diseases namely diabetes. Infection and non-healing of burn wounds and lack of angiogenesis in diabetic wounds lead to extensive injuries and death. Therefore, the design of wound dressings with antibacterial and restorative capabilities is very important. In this study, nanofibers (NFs) including polyurethane (PU) and hydroxypropyl methyl cellulose (HPMC) were prepared with different ratios and Mango peel extract (MPE) loaded into NFs by electrospinning method. The morphology, chemical structure, porosity, degradation, water vapor permeability, mechanical properties, wettability, antioxidant activity and some cell studies and evaluation of their antibacterial properties were investigated. The optimal mat (PU90/HPMC10) had a defect-free morphology with homogeneous NFs. Furthermore, it showed improved biodegradability, water vapor permeability and porosity compared to other Mats. All NFs were non-toxic with hydrophilic behavior in the cellular environment and had acceptable hemocompatibility. The PU90/HPMC10/20 % optimal scaffold had significantly higher cell viability and proliferation than other samples and also had a higher antibacterial ability against pathogenic bacteria S. aureus (17 mm) and E. coli (11 mm). All these findings confirm that the produced NF mats, especially those loaded with MPE, have a high potential to be used as an effective wound dressing.


Assuntos
Diabetes Mellitus , Mangifera , Nanofibras , Nanofibras/química , Derivados da Hipromelose , Vapor , Escherichia coli , Staphylococcus aureus , Diabetes Mellitus/tratamento farmacológico , Antibacterianos/química , Metilcelulose
17.
Int J Biol Macromol ; 259(Pt 2): 129267, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38199547

RESUMO

Chitosan packaging has been widely studied for food preservation, the application of which is expanded by the incorporation of tea polyphenols. This paper reviews the influence of tea polyphenols incorporation on chitosan-based packaging from the perspectives of physicochemical properties, bioactivity used for food preservation, and nutritional value. The physicochemical properties included optical properties, mechanical properties, water solubility, moisture content, and water vapor barrier property, concluding that the addition of tea polyphenols improved the opacity, water solubility, and water vapor barrier property of chitosan packaging, and the mechanical properties and water content were decreased. The bioactivity used for food preservation, that is antioxidant and antimicrobial properties, is enhanced by tea polyphenols, improving the preservation of food like meat, fruits, and vegetables. In the future, efforts will be needed to improve the mechanical properties of composite film and adjust the formula of tea polyphenols/chitosan composite film to apply to different foods. Besides, the identification and development of high nutritional value tea polyphenol/chitosan composite film is a valuable but challenging task. This review is expected to scientifically guide the application of tea polyphenols in chitosan packaging.


Assuntos
Quitosana , Quitosana/química , Polifenóis/farmacologia , Polifenóis/química , Vapor , Embalagem de Alimentos , Antioxidantes/farmacologia , Antioxidantes/química , Chá/química , Conservação de Alimentos
18.
Sci Total Environ ; 916: 169931, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38199368

RESUMO

Recent studies indicate an increase in the frequency of extreme compound dryness days (days with both extreme soil AND air dryness) across central Europe in the future, with little information on their impact on the functioning of trees and forests. This study aims to quantify and assess the impact of extreme soil dryness, extreme air dryness, and extreme compound dryness on the functioning of trees and forests. For this, >15 years of ecosystem-level (carbon dioxide and water vapor fluxes) and 6-10 years of tree-level measurements (transpiration and growth) each from a montane mixed deciduous forest (CH-Lae) and a subalpine evergreen coniferous forest (CH-Dav) in Switzerland, is used. The results showed extreme air dryness limitation on CO2 fluxes and extreme soil dryness limitations on water vapor fluxes. Additionally, CH-Dav was mainly affected by extreme air dryness whereas CH-Lae was affected by both extreme soil dryness and extreme air dryness. The impact of extreme compound dryness on net CO2 uptake (about 75 % decrease) was more due to higher increased ecosystem respiration (40 % and 70 % increase at CH-Dav and CH-Lae, respectively) than decreased gross primary productivity (10 % and 40 % decrease at CH-Dav and CH-Lae, respectively). A significant negative impact on evapotranspiration and transpiration was only observed at CH-Lae during extreme soil and compound dryness (about 25 % decrease). Furthermore, with some differences, the tree-level impact on tree water deficit, transpiration, and growth were consistent with the ecosystem-level impact on carbon uptake and evapotranspiration. Finally, the impact of extreme dryness showed no significant relationship with tree allometry (diameter and height) but across different tree species. The projected future is likely to expose these forest areas to more extreme and frequent dryness conditions, thus compromising the functioning of trees and forests, thereby calling for management interventions to increase the adaptive capacity and resistance of these forests.


Assuntos
Ecossistema , Árvores , Solo , Vapor , Florestas
19.
Int J Biol Macromol ; 260(Pt 2): 129171, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38171437

RESUMO

"Nine Steaming Nine Sun-Drying" Polygonti rhizome has been used as valuable tonic health-care products for thousands of years. This research aimed to determine the correlations between the structure and anti-diabetic activities of three novel polysaccharides isolated from the raw and "Nine Steaming Nine Sun-Drying" Polygonti rhizome, with PRP-R from the raw ones and PRP-9Z and PRP-9A from the steamed ones. Structures of the isolated polysaccharides were determined by IR and NMR spectra, as well as monosaccharide composition and methylation analysis. In vitro assays indicated that PRP-9Z could improve the glucose consumptions more effectively than PRP-R and PRP-9A via Akt/GSK3ß insulin signal pathway by western blotting analysis. In vivo assays indicated PRP-9Z could improve the glucose tolerance in the BKS-db mice. Histopathological assay demonstrated that PRP-9Z effectively reduced the damage of the kidney and liver. The above results indicated that PRP-9Z from "Nine Steaming Nine Sun-Drying" Polygonti rhizome showed significant anti-diabetic properties, which indicated that PRP-9Z with higher content of →1)-ß-Frup-(2→ was more active than PRP-R with higher →1,6)-ß-Fruf-(2→ and PRP-9A with higher →4)-ß-Galp(1→.


Assuntos
Polissacarídeos , Rizoma , Animais , Camundongos , Rizoma/química , Polissacarídeos/química , Vapor , Extratos Vegetais/química , Glucose/análise
20.
Int J Biol Macromol ; 260(Pt 1): 129317, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38211923

RESUMO

Chitosan (CH)-guar gum (GG) composite films crosslinked with tannic acid (TnA) were prepared by solution casting method. The films were then immersed in 5 % aqueous NH3 and dried again. They were characterized by IR spectroscopy, wide angle x-ray diffraction and thermogravimetric analysis. All the films were studied for physicochemical properties such as moisture content, swelling, solubility in water, water contact angle, water vapor permeability, opacity, tensile strength and antioxidant activity. The physicochemical and mechanical properties of films changed significantly when compared to CH as reflected by an increase in the amorphous domains of the films, a decrease in moisture content, swelling and solubility in water. The films turned hydrophobic with concomitant decrease in moisture content, swelling, water-solubility and exhibited improved UV absorption as well as mechanical strength, which in turn was dependent on the tannic acid concentration. These results along with enhanced antioxidant properties, UV absorption with no significant change in water vapor permeation compared to CH suggested that the films could find application in packaging applications.


Assuntos
Quitosana , Galactanos , Mananas , Gomas Vegetais , Polifenóis , Quitosana/química , Vapor , Resistência à Tração , Antioxidantes , Permeabilidade , Solubilidade , Embalagem de Alimentos
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