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1.
NPJ Biofilms Microbiomes ; 10(1): 55, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961111

RESUMO

Climate changes significantly impact greenhouse gas emissions from wetland soil. Specifically, wetland soil may be exposed to oxygen (O2) during droughts, or to sulfate (SO42-) as a result of sea level rise. How these stressors - separately and together - impact microbial food webs driving carbon cycling in the wetlands is still not understood. To investigate this, we integrated geochemical analysis, proteogenomics, and stoichiometric modeling to characterize the impact of elevated SO42- and O2 levels on microbial methane (CH4) and carbon dioxide (CO2) emissions. The results uncovered the adaptive responses of this community to changes in SO42- and O2 availability and identified altered microbial guilds and metabolic processes driving CH4 and CO2 emissions. Elevated SO42- reduced CH4 emissions, with hydrogenotrophic methanogenesis more suppressed than acetoclastic. Elevated O2 shifted the greenhouse gas emissions from CH4 to CO2. The metabolic effects of combined SO42- and O2 exposures on CH4 and CO2 emissions were similar to those of O2 exposure alone. The reduction in CH4 emission by increased SO42- and O2 was much greater than the concomitant increase in CO2 emission. Thus, greater SO42- and O2 exposure in wetlands is expected to reduce the aggregate warming effect of CH4 and CO2. Metaproteomics and stoichiometric modeling revealed a unique subnetwork involving carbon metabolism that converts lactate and SO42- to produce acetate, H2S, and CO2 when SO42- is elevated under oxic conditions. This study provides greater quantitative resolution of key metabolic processes necessary for the prediction of CH4 and CO2 emissions from wetlands under future climate scenarios.


Assuntos
Dióxido de Carbono , Metano , Oxigênio , Proteômica , Sulfatos , Áreas Alagadas , Sulfatos/metabolismo , Oxigênio/metabolismo , Proteômica/métodos , Metano/metabolismo , Dióxido de Carbono/metabolismo , Microbiologia do Solo , Microbiota , Bactérias/metabolismo , Bactérias/classificação , Bactérias/genética , Mudança Climática
2.
J Environ Sci (China) ; 146: 149-162, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38969443

RESUMO

Industrial wastewater should be treated with caution due to its potential environmental risks. In this study, a polymerization-based cathode/Fe3+/peroxydisulfate (PDS) process was employed for the first time to treat a raw coking wastewater, which can achieve simultaneous organics abatement and recovery by converting organic contaminants into separable solid organic-polymers. The results confirm that several dominant organic contaminants in coking wastewater such as phenol, cresols, quinoline and indole can be induced to polymerize by self-coupling or cross-coupling. The total chemical oxygen demand (COD) abatement from coking wastewater is 46.8% and the separable organic-polymer formed from organic contaminants accounts for 62.8% of the abated COD. Dissolved organic carbon (DOC) abatement of 41.9% is achieved with about 89% less PDS consumption than conventional degradation-based process. Operating conditions such as PDS concentration, Fe3+ concentration and current density can affect the COD/DOC abatement and organic-polymer yield by regulating the generation of reactive radicals. ESI-MS result shows that some organic-polymers are substituted by inorganic ions such as Cl-, Br-, I-, NH4+, SCN- and CN-, suggesting that these inorganic ions may be involved in the polymerization. The specific consumption of this coking wastewater treatment is 27 kWh/kg COD and 95 kWh/kg DOC. The values are much lower than those of the degradation-based processes in treating the same coking wastewater, and also are lower than those of most processes previously reported for coking wastewater treatment.


Assuntos
Coque , Polimerização , Eliminação de Resíduos Líquidos , Águas Residuárias , Poluentes Químicos da Água , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Sulfatos/química , Polímeros/química , Análise da Demanda Biológica de Oxigênio , Técnicas Eletroquímicas/métodos
3.
J Environ Sci (China) ; 146: 163-175, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38969445

RESUMO

Heterogeneous iron-based catalysts have drawn increasing attention in the advanced oxidation of persulfates due to their abundance in nature, the lack of secondary pollution to the environment, and their low cost over the last a few years. In this paper, the latest progress in the research on the activation of persulfate by heterogeneous iron-based catalysts is reviewed from two aspects, in terms of synthesized catalysts (Fe0, Fe2O3, Fe3O4, FeOOH) and natural iron ore catalysts (pyrite, magnetite, hematite, siderite, goethite, ferrohydrite, ilmenite and lepidocrocite) focusing on efforts made to improve the performance of catalysts. The advantages and disadvantages of the synthesized catalysts and natural iron ore were summarized. Particular interests were paid to the activation mechanisms in the catalyst/PS/pollutant system for removal of organic pollutants. Future research challenges in the context of field application were also discussed.


Assuntos
Ferro , Sulfatos , Poluentes Químicos da Água , Catálise , Ferro/química , Sulfatos/química , Poluentes Químicos da Água/química , Oxirredução , Eliminação de Resíduos Líquidos/métodos
4.
Mar Pollut Bull ; 204: 116556, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38850756

RESUMO

The Yellow Sea, characterized by an influx of both natural marine and anthropogenic pollutants, coupled with favorable photochemical conditions, serve as key sites for potential interactions between atmospheric gases and aerosols. A recent air monitoring campaign in the Yellow Sea revealed aerosol contributions from four sources, with the highest mass concentrations and dominance of NO3- (38.1 ± 0.37 %) during winds from China. Indications of potential secondary aerosol formation were observed through the presence of hydrolysis and oxidation products of nitrate and volatile organic compounds. Correlations between time series distributions of biomass burning organic aerosols and particle number counts (Dp 100-500 nm, R2 = 0.94) further suggest potential size growth through adsorption and scavenging processes. The results from this study provide observational evidence of a shift in atmospheric compositions from sulfate to nitrate, leading to an increased atmospheric nitrogen deposition in the Yellow Sea.


Assuntos
Aerossóis , Poluentes Atmosféricos , Monitoramento Ambiental , Aerossóis/análise , Poluentes Atmosféricos/análise , China , Nitratos/análise , Atmosfera/química , Compostos Orgânicos Voláteis/análise , Oceanos e Mares , Sulfatos/análise
5.
Sci Total Environ ; 943: 173732, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38851348

RESUMO

BACKGROUND AND OBJECTIVES: Groundwater contamination poses a significant health challenge in India, particularly impacting children. Despite its importance, limited research has explored the nexus between groundwater quality and child nutrition outcomes. This study addresses this gap, examining the association between groundwater quality and child undernutrition, offering pertinent insights for policymakers. DATA AND METHODS: The study uses data from the fifth round of the National Family Health Survey (NFHS) and the Central Groundwater Board (CGWB) to analyze the association between groundwater quality and child nutritional status. The groundwater quality data were collected by nationwide monitoring stations programmed by CGWB, and the child undernutrition data were obtained from the NFHS-5, 2019-21. The analysis included descriptive and logistic regression model. The study also considers various demographic and socio-economic factors as potential moderators of the relationship between groundwater quality and child undernutrition. FINDINGS: Significant variation in groundwater quality was observed across India, with numerous regions displaying poor performance. Approximately 26.53 % of geographical areas were deemed unfit for consuming groundwater. Environmental factors such as high temperatures, low precipitation, and arid, alluvial, laterite-type soils are linked to poorer groundwater quality. Unfit-for-consumption groundwater quality increased the odds of undernutrition, revealing a 35 %, 38 %, and 11 % higher likelihood of stunting, underweight, and wasting in children, with higher pH, Magnesium, Sulphate, Nitrate, Total Dissolved Solids, and Arsenic, levels associated with increased odds of stunting, underweight, and wasting. Higher temperatures (>25 °C), high elevations (>1000 m), and proximity to cultivated or industrial areas all contribute to heightened risks of child undernutrition. Children consuming groundwater, lacking access to improved toilets, or living in rural areas are more likely to be undernourished, while females, higher-income households, and those consuming dairy, vegetables, and fruits daily exhibit lower odds of undernutrition. POLICY IMPLICATIONS: Policy implications highlight the urgent need for investment in piped water supply systems. Additionally, focused efforts are required to monitor and improve groundwater quality in regions with poor water quality. Policies should emphasize safe sanitation practices and enhance public awareness about the critical role of safe drinking water in improving child health.


Assuntos
Água Subterrânea , Qualidade da Água , Monitoramento Ambiental , Água Subterrânea/química , Índia/epidemiologia , Desnutrição/epidemiologia , Poluição da Água/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Concentração de Íons de Hidrogênio , Política Ambiental , Política de Saúde , Arsênio/análise , Humanos , Criança , Sulfatos/análise , Magnésio , Cloretos
6.
Carbohydr Polym ; 341: 122345, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38876715

RESUMO

Sulfated fucan from sea cucumber is mainly consists of L-fucose and sulfate groups. Recent studies have confirmed that the structure of sulfated fucan mainly consists of repeating units, typically tetrasaccharides. However, there is growing evidence indicating the presence of irregular domains with heterogeneous units that have not been extensively explored. Moreover, as a key contributor to the nutritional benefits of sea cucumbers, sulfated fucan demonstrates a range of biological activities, such as anti-inflammatory, anticancer, hypolipidemic, anti-hyperglycemic, antioxidant, and anticoagulant properties. These biological activities are profoundly influenced by the structural features of sulfated fucan including molecular weight and distribution patterns of sulfate groups. The latest research indicates that sulfated fucan is dispersed in the extracellular matrix of the body wall of sea cucumbers. This article aimed to review the research progress on the in-situ distribution, structures, structural elucidation strategies, functions, and structure-activity relationships of sulfated fucan, especially in the last decade. It also provided insights into the major challenges and potential solutions in the research and development of sulfated fucan. Moreover, the fucanase and carbohydrate binding modules are anticipated to play pivotal roles in advancing this field.


Assuntos
Polissacarídeos , Pepinos-do-Mar , Pepinos-do-Mar/química , Animais , Polissacarídeos/química , Polissacarídeos/farmacologia , Relação Estrutura-Atividade , Sulfatos/química , Anticoagulantes/química , Anticoagulantes/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Humanos , Antineoplásicos/química , Antineoplásicos/farmacologia , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia
7.
Mar Drugs ; 22(6)2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38921576

RESUMO

Three polysaccharides (SnNG, SnFS and SnFG) were purified from the body wall of Stichopus naso. The physicochemical properties, including monosaccharide composition, molecular weight, sulfate content, and optical rotation, were analyzed, confirming that SnFS and SnFG are sulfated polysaccharides commonly found in sea cucumbers. The highly regular structure {3)-L-Fuc2S-(α1,}n of SnFS was determined via a detailed NMR analysis of its oxidative degradation product. By employing ß-elimination depolymerization of SnFG, tri-, penta-, octa-, hendeca-, tetradeca-, and heptadeca-saccharides were obtained from the low-molecular-weight product. Their well-defined structures confirmed that SnFG possessed the backbone of {D-GalNAc4S6S-ß(1,4)-D-GlcA}, and each GlcA residue was branched with Fuc2S4S. SnFS and SnFG are both structurally the simplest version of natural fucan sulfate and fucosylated glycosaminoglycan, facilitating the application of low-value sea cucumbers S. naso. Bioactivity assays showed that SnFG and its derived oligosaccharides exhibited potent anticoagulation and intrinsic factor Xase (iXase) inhibition. Moreover, a comparative analysis with the series of oligosaccharides solely branched with Fuc3S4S showed that in oligosaccharides with lower degrees of polymerization, such as octasaccharides, Fuc2S4S led to a greater increase in APTT prolongation and iXase inhibition. As the degree of polymerization increases, the influence from the sulfation pattern diminishes, until it is overshadowed by the effects of molecular weight.


Assuntos
Anticoagulantes , Peso Molecular , Oligossacarídeos , Polissacarídeos , Animais , Anticoagulantes/farmacologia , Anticoagulantes/química , Anticoagulantes/isolamento & purificação , Polissacarídeos/farmacologia , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Oligossacarídeos/farmacologia , Oligossacarídeos/química , Oligossacarídeos/isolamento & purificação , Stichopus/química , Pepinos-do-Mar/química , Sulfatos/química , Espectroscopia de Ressonância Magnética , Coagulação Sanguínea/efeitos dos fármacos
8.
Environ Sci Pollut Res Int ; 31(27): 39533-39548, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38822960

RESUMO

The present study evaluated a solvo-metallurgical technique for metal extraction from industrial solid waste (jarosite) using ionic liquids (ILs) and waste-derived solvents. The jarosite contains a considerable amount of metal ions, namely iron, zinc, and lead. The jarosite was characterized by XRF, XRD, SEM, and FTIR techniques. The parameters affecting metal extraction, such as stirring time, acid molarity, and temperature, have been examined. Aliquat 336 was used to extract metals from fresh and roasted jarosite after equilibration with HCl. The response surface methodology (RSM) was used to optimize the parameters for the maximum metal extraction using [A336] [Cl]. Maximum extraction of iron (86.75%), zinc (51.96%), and lead (94.38%) from roasted jarosite was achieved at optimum conditions (125-min stirring time, 5 M acid molarity, and 20 ml/g liquid-to-solid ratio). Furthermore, the metal extraction was investigated using waste-derived solvents. The results show that waste-derived solvents, such as biomass and plastic pyrolysis oil, can effectively extract metals from fresh and roasted jarosite. Biomass pyrolysis oil achieved the highest extraction at 50 °C for 90 min, while plastic pyrolysis oil achieved the highest extraction at 50 °C for 60 min from roasted jarosite. These solvents are also cost-effective because they are made from waste plastic and biomass.


Assuntos
Líquidos Iônicos , Solventes , Zinco , Líquidos Iônicos/química , Solventes/química , Zinco/química , Metais/química , Chumbo , Ferro/química , Compostos Férricos , Sulfatos
9.
J Hazard Mater ; 475: 134907, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38878442

RESUMO

In this study, the activation of peroxydisulfate (PS) by K2FeO4-activation biochar (KFeB) and acid-picking K2FeO4-activation biochar (AKFeB) was investigated to reveal the mechanism differences between iron site and graphitic structure in sulfadiazine (SDZ) degradation and ARB inactivation, respectively. KFeB/PS and AKFeB/PS systems had similar degradation property towards SDZ, but only KFeB/PS system showed excellent bactericidal property. The mechanism study demonstrated that dissolved SDZ was degraded through electron transfer pathway mediated by graphitic structure, while suspended ARB was inactivated through free radicals generated by iron-activated PS, accompanied by excellent removal on antibiotic resistance genes (ARGs). The significant decrease in conjugative transfer frequency indicated the reduced horizontal gene transfer risk of ARGs after treatment with KFeB/PS system. Transcriptome data suggested that membrane protein channel disruption and adenosine triphosphate synthesis inhibition were key reasons for conjugative transfer frequency reduction. Continuous flow reactor of KFeB/PS system can efficiently remove antibiotics and ARB, implying the potential application in practical wastewater purification. In conclusion, this study provides novel insights for classified and collaborative control of antibiotics and ARB by carbon-based catalysts driven persulfate advanced oxidation technology.


Assuntos
Antibacterianos , Carvão Vegetal , Grafite , Ferro , Sulfadiazina , Sulfatos , Carvão Vegetal/química , Sulfadiazina/química , Antibacterianos/química , Antibacterianos/farmacologia , Ferro/química , Ferro/metabolismo , Grafite/química , Sulfatos/química , Sulfatos/metabolismo , Poluentes Químicos da Água/química , Farmacorresistência Bacteriana/genética , Resistência Microbiana a Medicamentos/genética , Bactérias/metabolismo , Bactérias/efeitos dos fármacos , Bactérias/genética , Purificação da Água/métodos , Peróxidos/química
10.
Environ Sci Technol ; 58(24): 10415-10444, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38848315

RESUMO

Persulfate (PS)-based advanced oxidation processes (AOPs) for pollutant removal have attracted extensive interest, but some controversies about the identification of reactive species were usually observed. This critical review aims to comprehensively introduce basic concepts and rectify cognitive biases and appeals to pay more attention to experimental details in PS-AOPs, so as to accurately explore reaction mechanisms. The review scientifically summarizes the character, generation, and identification of different reactive species. It then highlights the complexities about the analysis of electron paramagnetic resonance, the uncertainties about the use of probes and scavengers, and the necessities about the determination of scavenger concentration. The importance of the choice of buffer solution, operating mode, terminator, and filter membrane is also emphasized. Finally, we discuss current challenges and future perspectives to alleviate the misinterpretations toward reactive species and reaction mechanisms in PS-AOPs.


Assuntos
Oxirredução , Sulfatos/química
11.
Sci Rep ; 14(1): 14831, 2024 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937529

RESUMO

Pomegranate (Punica granatum L.) fruit quality depends on many traits including visual, biochemical and mineral characteristics. One of the negative traits is aril whitening (AW) which is a frequently observed disorder in hot and dry climates, that leads to decline in desirable fruit quality. Color, antioxidant, and mineral contents of the arils are of prime importance as quality traits. Therefore, this study aims to investigate the effect of shading and foliar minerals on fruit quality during the fruit development stages of pomegranate. Treatments included shaded (50% green net) and unshaded trees and foliar application of trees with potassium sulfate (K, 1% and 2%) or sodium silicate (Si, 0.05, 0.1 and 0.15%) during two growing seasons. Results showed that the severity of AW at harvest decreased significantly when trees were covered with shading compared to control. The color values of L* and °hue for arils were lower in fruits grown under shading conditions indicating darker red arils. Shading significantly reduced chilling injury in cold storage compared to open field fruits. Shading and Si 0.15% increased superoxide dismutase, and catalase enzymes activity while decreased Polyphenol oxidase and peroxidase. Covering trees with shading and Si 0.15% spray resulted in the highest total anthocyanin, antioxidant activity, and total phenolics content in the arils. Shading as well as Si 0.15% increased macronutrients content of the arils. The study concluded that covering pomegranate trees and spraying with Si in hot climate reduced AW, increased antioxidant traits, and led to higher fruit quality.


Assuntos
Antioxidantes , Frutas , Minerais , Punica granatum , Silicatos , Sulfatos , Antioxidantes/metabolismo , Frutas/química , Frutas/efeitos dos fármacos , Frutas/metabolismo , Punica granatum/química , Sulfatos/análise , Minerais/análise , Minerais/metabolismo , Cor , Antocianinas/análise , Antocianinas/metabolismo
12.
Biofouling ; 40(5-6): 333-347, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38836545

RESUMO

The corrosion behaviors of four pure metals (Fe, Ni, Mo and Cr) in the presence of sulfate reducing bacteria (SRB) were investigated in enriched artificial seawater (EASW) after 14-day incubation. Metal Fe and metal Ni experienced weight losses of 1.96 mg cm-2 and 1.26 mg cm-2, respectively. In contrast, metal Mo and metal Cr exhibited minimal weight losses, with values of only 0.05 mg cm-2 and 0.03 mg cm-2, respectively. In comparison to Mo (2.2 × 106 cells cm-2) or Cr (1.4 × 106 cells cm-2) surface, the sessile cell counts on Fe (4.0 × 107 cells cm-2) or Ni (3.1 × 107 cells cm-2) surface was higher.


Assuntos
Aderência Bacteriana , Sulfatos , Corrosão , Sulfatos/química , Metais/química , Água do Mar/microbiologia , Água do Mar/química , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Bactérias/efeitos dos fármacos , Incrustação Biológica/prevenção & controle
13.
Environ Sci Pollut Res Int ; 31(30): 43249-43261, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38898350

RESUMO

Carbon materials have been receiving considerable attention as effective green catalysts for peroxydisulfate (PDS) activation to degrade organic pollutants. Herein, the porous graphene-like carbons (PGCs) were synthesized by pyrolyzing a nitrogen-rich biomass (peanut shell, PS) in the eutectic mixture of FeCl3 and ZnCl2. The results suggested that involvement of molten salts attributed the biochar the amazing properties such as high specific surface area (SBET = 2529.4 m2 g-1), abundant structural defects, high nitrogen content (6.5%), and oxygen-containing functional groups on its surface. Especially when pyrolyzed at activation temperature of 800 °C, mass ratio of 1:3:15 (PS:ZnCl2:FeCl3), and activation time of 2 h, the optimized PGCs-op exhibited outstanding performance in the catalytic degradation of rhodamine B (RhB). Almost all of RhB (99.02%) was removed in 40 min and basically not influenced by initial pH in the range of 3.00 to 9.98. Although the RhB degradation was influenced by anions (Cl-, HCO3-, HPO42-), the inhibition would be significantly alleviated within 120 min unless these substances were high in concentration. Furthermore, the quenching tests revealed that the reactive species were involved in RhB degradation in the sequence of 1O2 > O2∙- > SO4∙- > ∙OH, among which singlet oxygen played a crucial role. Combined with characterization analysis, a possible mechanism of RhB degradation in PGCs-op/PDS system was proposed. Overall, this study provided a promising metal-free catalyst for the removal of organic pollutants while achieving reutilization of the waste biomass.


Assuntos
Grafite , Rodaminas , Rodaminas/química , Grafite/química , Catálise , Porosidade , Poluentes Químicos da Água/química , Carbono/química , Sulfatos/química
14.
Int J Biol Macromol ; 273(Pt 2): 132882, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38848853

RESUMO

Ulvan, a sulfated polysaccharide extracted from Ulva spp., has garnered significant attention in the food and pharmaceutical industries due to its potential health benefits. These include immunomodulation, antiviral, anti-inflammatory, anti-hyperlipidemic, and anti-cancer effects. Nonetheless, practical applications in these fields remain limited due to an incomplete understanding of its gelation mechanisms. Additionally, the underlying mechanisms of its gelation have not been completely understood and thoroughly reviewed. The primary objective is to provide current insights into ulvan's gelling mechanisms and potential health impacts. This review also delves into the existing applications of ulvan polysaccharides. By unraveling these aspects, the information provided in this work is expected to deepen our understanding of ulvan's gelation mechanisms and its prospective role in enhancing health, holding promise for advancements in the fields of food science and disease prevention. This work's theoretical insights contribute significantly to a deeper understanding of these aspects, which holds paramount importance in unleashing the full potential of ulvan and elevating its scientific significance.


Assuntos
Géis , Polissacarídeos , Sulfatos , Ulva , Ulva/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Géis/química , Humanos , Sulfatos/química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia
15.
Int J Biol Macromol ; 272(Pt 1): 132845, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38830495

RESUMO

Brown seaweed-derived polysaccharides, notably fucoidan and laminarin, are known for their extensive array of bioactivities and physicochemical properties. However, the effects of upper digestive tract modification on the bioactive performance of fucoidan and laminarin fractions (FLFs) sourced from Australian native species are largely unknown. Here, the digestibility and bioaccessibility of FLFs were evaluated by tracking the dynamic changes in reducing sugar content (CR), profiling the free monosaccharide composition using LC-MS, and comparing high-performance gel permeation chromatography profile variation via LC-SEC-RI. The effects of digestive progression on bioactive performance were assessed by comparing the antioxidant and antidiabetic potential of FLFs and FLF digesta. We observed that molecular weight (Mw) decreased during gastric digestion indicating that FLF aggregates were disrupted in the stomach. During intestinal digestion, Mw gradually decreased and CR increased indicating cleavage of glycosidic bonds releasing free sugars. Although the antioxidant and antidiabetic capacities were not eliminated by the digestion progression, the bioactive performance of FLFs under a digestive environment was reduced contrasting with the same concentration level of the undigested FLFs. These data provide comprehensive information on the digestibility and bioaccessibility of FLFs, and shed light on the effects of digestive progression on bioactive expression.


Assuntos
Antioxidantes , Polissacarídeos , Alga Marinha , Polissacarídeos/química , Polissacarídeos/farmacologia , Alga Marinha/química , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/metabolismo , Trato Gastrointestinal Superior/metabolismo , Trato Gastrointestinal Superior/efeitos dos fármacos , Peso Molecular , Hipoglicemiantes/farmacologia , Hipoglicemiantes/química , Digestão/efeitos dos fármacos , Sulfatos/química , Glucanos/química , Glucanos/farmacologia , Phaeophyceae/química , Humanos
16.
Sci Rep ; 14(1): 12651, 2024 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-38825618

RESUMO

Effective disinfection methods are crucial in the cold chain transportation process of food due to the specificity of temperature and the diversity of contaminated flora. The objective of this study was to investigate the sanitizing effect of different disinfectants on various fungi at - 20 °C to achieve accurate disinfection of diverse bacterial populations. Peracetic acid, hydrogen peroxide, and potassium bisulfate were selected as low-temperature disinfectants and were combined with antifreeze. The sanitizing effect of these cryogenic disinfectants on pathogens such as Bacillus subtilis black variant spores (ATCC9372), Staphylococcus aureus (ATCC 6538), Candida albicans (ATCC 10231), Escherichia coli (8099), and poliovirus (PV-1) was sequentially verified by bactericidal and virus inactivation experiments. After a specified time of disinfection, a neutralizing agent was used to halt the sanitizing process. The study demonstrates that different disinfectants exhibit selective effects during the low-temperature disinfection process. Peracetic acid, hydrogen peroxide, and potassium monopersulfate are suitable for the low-temperature environmental disinfection of bacterial propagules, viruses, and fungal contaminants. However, for microorganisms with strong resistance to spores, a low-temperature disinfectant based on peracetic acid should be chosen for effective disinfection treatment. Our results provide a valuable reference for selecting appropriate disinfectants to sanitize various potential pathogens in the future.


Assuntos
Temperatura Baixa , Desinfetantes , Desinfecção , Peróxido de Hidrogênio , Ácido Peracético , Desinfetantes/farmacologia , Desinfecção/métodos , Peróxido de Hidrogênio/farmacologia , Ácido Peracético/farmacologia , Sulfatos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Compostos de Potássio/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Poliovirus/efeitos dos fármacos
17.
Nat Chem ; 16(6): 881-892, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38844638

RESUMO

Ganglioside glycans are ubiquitous and complex biomolecules that are involved in a wide range of biological functions and disease processes. Variations in sialylation and sulfation render the structural complexity and diversity of ganglioside glycans, and influence protein-carbohydrate interactions. Structural and functional insights into the biological roles of these glycans are impeded due to the limited accessibility of well-defined structures. Here we report an integrated chemoenzymatic strategy for expeditious and systematic synthesis of a comprehensive 65-membered ganglioside glycan library covering all possible patterns of sulfation and sialylation. This strategy relies on the streamlined modular assembly of three common sialylated precursors by highly stereoselective iterative sialylation, modular site-specific sulfation through flexible orthogonal protecting-group manipulations and enzymatic-catalysed diversification using three sialyltransferase modules and a galactosidase module. These diverse ganglioside glycans enable exploration into their structure-function relationships using high-throughput glycan microarray technology, which reveals that different patterns of sulfation and sialylation on these glycans mediate their unique binding specificities.


Assuntos
Gangliosídeos , Polissacarídeos , Polissacarídeos/química , Polissacarídeos/metabolismo , Gangliosídeos/química , Gangliosídeos/metabolismo , Sialiltransferases/metabolismo , Sialiltransferases/química , Sulfatos/química , Sulfatos/metabolismo , Glicômica/métodos
18.
J Proteome Res ; 23(7): 2386-2396, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38900499

RESUMO

Tyrosine sulfation, an understudied but crucial post-translational modification, cannot be directly detected in conventional nanoflow liquid chromatography-tandem mass spectrometry (nanoLC-MS/MS) due to the extreme sulfate lability. Here, we report the detection of sulfate-retaining fragments from LC-electron capture dissociation (ECD) and nanoLC-electron transfer higher energy collision dissociation (EThcD). Sulfopeptide candidates were identified by Proteome Discoverer and MSFragger analysis of nanoLC-HCD MS/MS data and added to inclusion lists for LC-ECD or nanoLC-EThcD MS/MS. When this approach failed, targeted LC-ECD with fixed m/z isolation windows was performed. For the plasma protein fibrinogen, the known pyroglutamylated sulfopeptide QFPTDYDEGQDDRPK from the beta chain N-terminus was identified despite a complete lack of sulfate-containing fragment ions. The peptide QVGVEHHVEIEYD from the gamma-B chain C-terminus was also identified as sulfated or phosphorylated. This sulfopeptide is not annotated in Uniprot but was previously reported. MSFragger further identified a cysteine-containing peptide from the middle of the gamma chain as sulfated and deamidated. NanoLC-EThcD and LC-ECD MS/MS confirmed the two former sulfopeptides via sulfate-retaining fragment ions, whereas an unexpected fragmentation pattern was observed for the third sulfopeptide candidate. Manual interpretation of the LC-ECD spectrum revealed two additional isobaric identifications: a trisulfide-linked cysteinyl-glycine or a carbamidomethyl-dithiothreiotol covalent adduct. Synthesis of such adducts confirmed the latter identity.


Assuntos
Fibrinogênio , Espectrometria de Massas em Tandem , Tirosina , Tirosina/química , Tirosina/análogos & derivados , Espectrometria de Massas em Tandem/métodos , Fibrinogênio/química , Fibrinogênio/metabolismo , Cromatografia Líquida/métodos , Humanos , Processamento de Proteína Pós-Traducional , Tripsina/química , Tripsina/metabolismo , Sulfatos/química , Sequência de Aminoácidos , Peptídeos/química , Peptídeos/análise , Elétrons
19.
Int J Biol Macromol ; 273(Pt 1): 133121, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38876229

RESUMO

GFP1, a sulfated polysaccharide extracted from Grateloupia filicina, exhibits remarkable immunomodulatory activity. To reduce the side effects of 5-fluorouracil (5-FU), GFP1 was employed as a macromolecular carrier to synthesize of GFP1-C-5-FU by reacting with carboxymethyl-5-fluorouracil (C-5-FU). Subsequently, this new compound was reacted with folic acid (FA) through an ester bond, forming novel conjugates named GFP1-C-5-FU-FA. Nuclear magnetic resonance analysis confirmed the formation of GFP1-C-5-FU-FA. In vitro drug release studies revealed that the cumulative release rate of C-5-FU reached 46.9 % in phosphate buffer (pH 7.4) after 96 h, a rate significantly higher than that of the control groups, indicating the controlled drug release behavior of GFP1-C-5-FU-FA. Additionally, in vitro anticancer assays demonstrated the potent anticancer activity of GFP1-C-5-FU-FA conjugates, as evidenced by the reduced viability of HeLa and AGS cancer cells, along with increased levels of apoptosis and cellular uptake. Western blot analysis indicated that the GFP1-C-5-FU-FA conjugate effectively enhanced phosphorylation in cancer cells through the NF-kB and MAPK pathways, thereby promoting apoptosis. These findings highlight the potential of folate-targeted conjugates in efficiently treating HeLa and AGS cancer cells in vitro and lay a robust theoretical groundwork for future in vivo anti-cancer research involving these cells.


Assuntos
Antineoplásicos , Fluoruracila , Ácido Fólico , Polissacarídeos , Fluoruracila/farmacologia , Fluoruracila/química , Humanos , Ácido Fólico/química , Ácido Fólico/farmacologia , Polissacarídeos/química , Polissacarídeos/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Sulfatos/química , Células HeLa , Liberação Controlada de Fármacos , Sistemas de Liberação de Medicamentos , Portadores de Fármacos/química , Sobrevivência Celular/efeitos dos fármacos
20.
Water Res ; 259: 121869, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38851113

RESUMO

This work aims to explore the ability of molten salt to solve salt deposition in supercritical water (SCW) related technologies including supercritical water oxidation and supercritical water gasification, with KNO3 and Na2SO4 as examples. In the pure KNO3 solution, the two-phase layering of high-density KNO3 molten salt (settling at the reactor bottom) and low-density saturated KNO3-SCW salt solution (flowing out at the top outlet of the reactor) was formed in a kettle-reactor with about 6.5 ratio of depth to inner diameter, thereby improving the accuracy of measured solubilities. The precipitation macro-characteristics of mixed KNO3 and Na2SO4 in SCW were investigated under different feed concentration conditions. The results showed that Na2SO4 deposition on the reactor sidewall could be reduced by more than 90 % when the mass ratio of KNO3 to Na2SO4 in the feed was only 0.167. No visible salt deposition was observed on the sidewall when the ratio was 0.374. All solid deposited salts were converted into the liquid molten salt as the ratio reached 3.341, and thus could easily flow out of the reactor, without plugging. 'Molten salt dissolution' mechanism may provide a more plausible explanation for mixed KNO3 and Na2SO4 in SCW. In addition, the precipitation micro-mechanisms of mixed KNO3 and Na2SO4, and the critical conditions of avoiding sidewall deposition and reactor plugging were proposed. This work is valuable for overcoming the salt deposition problem in SCW-related technologies.


Assuntos
Precipitação Química , Compostos de Potássio , Sulfatos , Água , Sulfatos/química , Água/química , Compostos de Potássio/química , Nitratos/química , Solubilidade
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