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1.
Mar Drugs ; 19(8)2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34436245

RESUMO

SARS-CoV-2 (severe acute respiratory syndrome coronavirus-2) is a novel coronavirus strain that emerged at the end of 2019, causing millions of deaths so far. Despite enormous efforts being made through various drug discovery campaigns, there is still a desperate need for treatments with high efficacy and selectivity. Recently, marine sulfated polysaccharides (MSPs) have earned significant attention and are widely examined against many viral infections. This article attempted to produce a comprehensive report about MSPs from different marine sources alongside their antiviral effects against various viral species covering the last 25 years of research articles. Additionally, these reported MSPs were subjected to molecular docking and dynamic simulation experiments to ascertain potential interactions with both the receptor-binding domain (RBD) of SARS CoV-2's spike protein (S-protein) and human angiotensin-converting enzyme-2 (ACE2). The possible binding sites on both S-protein's RBD and ACE2 were determined based on how they bind to heparin, which has been reported to exhibit significant antiviral activity against SARS CoV-2 through binding to RBD, preventing the virus from affecting ACE2. Moreover, our modeling results illustrate that heparin can also bind to and block ACE2, acting as a competitor and protective agent against SARS CoV-2 infection. Nine of the investigated MSPs candidates exhibited promising results, taking into consideration the newly emerged SARS CoV-2 variants, of which five were not previously reported to exert antiviral activity against SARS CoV-2, including sulfated galactofucan (1), sulfated polymannuroguluronate (SPMG) (2), sulfated mannan (3), sulfated heterorhamnan (8), and chondroitin sulfate E (CS-E) (9). These results shed light on the importance of sulfated polysaccharides as potential SARS-CoV-2 inhibitors.


Assuntos
Antivirais/farmacologia , Organismos Aquáticos/química , Polissacarídeos/farmacologia , SARS-CoV-2/química , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/metabolismo , Antivirais/química , Sítios de Ligação , Simulação por Computador , Heparina/química , Heparina/metabolismo , Humanos , Simulação de Acoplamento Molecular , Polissacarídeos/química , Ligação Proteica , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Relação Estrutura-Atividade , Sulfatos/química
2.
Molecules ; 26(16)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34443481

RESUMO

This study explores the capability of Sulfate Radical-based Advanced Oxidation Processes (SR-AOPs) for the simultaneous disinfection and decontamination of urban wastewater. Sulfate and hydroxyl radicals in solution were generated activating peroxymonosulfate (PMS) under UV-C irradiation at pilot plant scale. The efficiency of the process was assessed toward the removal of three CECs (Trimethoprim (TMP), Sulfamethoxazole (SMX), and Diclofenac (DCF)) and three bacteria (Escherichia coli, Enterococcus spp., and Pseudomonas spp.) in actual urban wastewater (UWW), obtaining the optimal value of PMS at 0.5 mmol/L. Under such experimental conditions, bacterial concentration ≤ 10 CFU/100 mL was reached after 15 min of UV-C treatment (0.03 kJ/L of accumulative UV-C radiation) for natural occurring bacteria, no bacterial regrowth was observed after 24 and 48 h, and 80% removal of total CECs was achieved after 12 min (0.03 kJ/L), with a release of sulfate ions far from the limit established in wastewater discharge. Moreover, the inactivation of Ampicillin (AMP), Ciprofloxacin (CPX), and Trimethoprim (TMP) antibiotic-resistant bacteria (ARB) and reduction of target genes (ARGs) were successfully achieved. Finally, a harmful effect toward the receiving aquatic environment was not observed according to Aliivibrio fischeri toxicity tests, while a slightly toxic effect toward plant growth (phytotoxicity tests) was detected. As a conclusion, a cost analysis demonstrated that the process could be feasible and a promising alternative to successfully address wastewater reuse challenges.


Assuntos
Peróxidos/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Purificação da Água/métodos , Aliivibrio fischeri/efeitos dos fármacos , Antibacterianos/química , Bactérias/efeitos dos fármacos , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Resistência Microbiana a Medicamentos/genética , Oxirredução , Plantas/efeitos dos fármacos , Sulfatos/química , Raios Ultravioleta , Águas Residuárias/análise , Águas Residuárias/microbiologia , Águas Residuárias/toxicidade , Poluentes Químicos da Água/efeitos da radiação
3.
Int J Mol Sci ; 22(14)2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34299374

RESUMO

Nano Ru-based catalysts, including monometallic Ru and Ru-Zn nanoparticles, were synthesized via a precipitation method. The prepared catalysts were evaluated on partial hydrogenation of benzene towards cyclohexene generation, during which the effect of reaction modifiers, i.e., ZnSO4, MnSO4, and FeSO4, was investigated. The fresh and the spent catalysts were thoroughly characterized by XRD, TEM, SEM, XPS, XRF, and DFT studies. It was found that Zn2+ or Fe2+ could be adsorbed on the surface of a monometallic Ru catalyst, where a stabilized complex could be formed between the cations and the cyclohexene. This led to an enhancement of catalytic selectivity towards cyclohexene. Furthermore, electron transfer was observed from Zn2+ or Fe2+ to Ru, hindering the catalytic activity towards benzene hydrogenation. In comparison, very few Mn2+ cations were adsorbed on the Ru surface, for which no cyclohexene could be detected. On the other hand, for Ru-Zn catalyst, Zn existed as rodlike ZnO. The added ZnSO4 and FeSO4 could react with ZnO to generate (Zn(OH)2)5(ZnSO4)(H2O) and basic Fe sulfate, respectively. This further benefited the adsorption of Zn2+ or Fe2+, leading to the decrease of catalytic activity towards benzene conversion and the increase of selectivity towards cyclohexene synthesis. When 0.57 mol·L-1 of ZnSO4 was applied, the highest cyclohexene yield of 62.6% was achieved. When MnSO4 was used as a reaction modifier, H2SO4 could be generated in the slurry via its hydrolysis, which reacted with ZnO to form ZnSO4. The selectivity towards cyclohexene formation was then improved by the adsorbed Zn2+.


Assuntos
Benzeno/química , Compostos Ferrosos/química , Compostos de Manganês/química , Rutênio/química , Sulfatos/química , Sulfato de Zinco/química , Catálise , Cicloexenos/química , Hidrogenação , Ferro/química
4.
Phys Chem Chem Phys ; 23(26): 14212-14223, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34159996

RESUMO

Lipid membranes are a key component of contemporary living systems and are thought to have been essential to the origin of life. Most research on membranes has focused on situations restricted to ambient physiological or benchtop conditions. However, the influence of more extreme conditions, such as the deep subsurface on Earth or extraterrestrial environments are less well understood. The deep subsurface environments of Mars, for instance, may harbor high concentrations of chaotropic salts in brines, yet we know little about how these conditions would influence the habitability of such environments for cellular life. Here, we investigated the combined effects of high concentrations of salts, including sodium and magnesium perchlorate and sulfate, and high hydrostatic pressure on the stability and structure of model biomembranes of varying complexity. To this end, a variety of biophysical techniques have been applied, which include calorimetry, fluorescence spectroscopies, small-angle X-ray scattering, dynamic light scattering, and microscopy techniques. We show that the structure and phase behavior of lipid membranes is sensitively dictated by the nature of the salt, in particular its anion and its concentration. We demonstrate that, with the exception of magnesium perchlorate, which can also induce cubic lipid arrangements, long-chain saturated lipid bilayer structures can still persist at high salt concentrations across a range of pressures. The lateral organization of complex heterogeneous raft-like membranes is affected by all salts. For simple, in particular bacterial membrane-type bilayer systems with unsaturated chains, vesicular structures are still stable at Martian brine conditions, also up to the kbar pressure range, demonstrating the potential compatibility of environments containing such ionic and pressure extremes to lipid-encapsulated life.


Assuntos
Meio Ambiente Extraterreno/química , Fosfolipídeos/química , Pressão Atmosférica , Compostos de Magnésio/química , Sulfato de Magnésio/química , Marte , Conformação Molecular , Percloratos/química , Sais/química , Compostos de Sódio/química , Espectrometria de Fluorescência , Relação Estrutura-Atividade , Sulfatos/química , Termodinâmica
5.
J Mater Chem B ; 9(24): 4929-4940, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34105573

RESUMO

The preparation of an antioxidant hybrid material by controlled heteroaggregation of manganese oxide nanoparticles (MnO2 NPs) and sulfate-functionalized polystyrene latex (SL) beads was accomplished. Negatively charged MnO2 NPs were prepared by precipitation and initially functionalized with poly(diallyldimethylammonium chloride) (PDADMAC) polyelectrolyte to induce charge reversal allowing decoration of oppositely charged SL surfaces via simple mixing. The PDADMAC-functionalized MnO2 NPs (PMn) aggregated with the SL particles leading to the formation of negatively charged, neutral and positively charged (SPMn) composites. The charge neutralization resulted in rapidly aggregating dispersions, while stable samples were observed once the composites possessed sufficiently high negative and positive charge, below and above the charge neutralization point, respectively. The antioxidant assays revealed that SL served as a suitable substrate and that the PDADMAC functionalization and immobilization of MnO2 NPs did not compromise their catalase (CAT) and superoxide dismutase (SOD)-like activities, which were also maintained within a wide temperature range. The obtained SPMn composite is expected to be an excellent candidate as an antioxidant material for the efficient scavenging of reactive oxygen species at both laboratory and larger scales, even under harsh conditions, where natural antioxidants do not function.


Assuntos
Biocatálise , Látex/química , Compostos de Manganês/química , Óxidos/química , Espécies Reativas de Oxigênio/química , Sulfatos/química
6.
Chem Commun (Camb) ; 57(55): 6784-6787, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34137389

RESUMO

Lanthanide dodecyl sulfates, LnDSx, are remarkably effective to catalyze the reaction of diepoxides with diamines in the liquid and solid states, a key reaction in the formation of epoxy thermosets. Among all lanthanides, the lanthanum complex LaNa(DS)4(H2O)2 is the most active, allowing a decrease of 60 kJ mol-1 of the activation energy between polyethylene imine and limonene dioxide, a biobased epoxy monomer.


Assuntos
Compostos de Epóxi/química , Elementos da Série dos Lantanídeos/química , Sulfatos/química , Temperatura , Catálise
7.
Molecules ; 26(11)2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34071646

RESUMO

The use of substrates supplemented with minerals is a promising strategy for increasing the nutraceutical value of Pleurotus spp. The current research was performed to analyze the effect of substrate supplementation with magnesium (Mg) salts on the Mg content, biomass, and chemical composition of pink oyster mushroom (Pleurotus djamor) fruiting bodies. Before inoculation, substrate was supplemented with MgCl2 × 6 H2O and MgSO4, both salts were applied at three concentrations: 210, 420, and 4200 mg of Mg per 2 kg of substrate. The harvest period included three flushes. Substrate supplementation with 4200 mg of Mg caused the most significant decrease in mushroom productivity, of about 28% for both Mg salts. The dry matter content in fruiting bodies was significantly lower in the treatment in which 210 mg of Mg was applied as MgSO4 in comparison to the control. Supplementation effectively increased the Mg content in fruiting bodies of P. djamor by 19-85% depending on the treatment, and significantly affected the level of remaining bioelements and anions. One hundred grams of pink oyster fruiting bodies, supplemented with Mg salts, provides more than 20% of the Mg dietary value recommended by the Food and Drug Administration (FDA); thus, supplementation can be an effective technique for producing mushrooms that are rich in dietary Mg. Although P. djamor grown in supplemented substrate showed lower productivity, this was evident only in the fresh weight because the differences in dry weight were negligible. Mg supplementation increased the antioxidant activity of the fruiting bodies, phenolic compounds, and some amino acids, including L-tryptophan, and vitamins (thiamine and l-ascorbic acid).


Assuntos
Suplementos Nutricionais , Carpóforos/química , Magnésio/química , Pleurotus/metabolismo , Agaricales , Ácido Ascórbico/análise , Ácido Ascórbico/química , Biofortificação , Cloretos/química , Meios de Cultura , Tecnologia de Alimentos , Alimento Funcional , Fenol/química , Fenóis/química , Pleurotus/química , Sais/química , Secale/microbiologia , Açúcares/química , Sulfatos/química , Tiamina/análise , Triptofano/análise
8.
Int J Biol Macromol ; 183: 2044-2054, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34097960

RESUMO

Targeted delivery and controlled release of drugs are attractive methods for avoiding the drug's leakage during blood circulation and burst release of the drug. We prepared a nano cellulose-based drug delivery system (DDS) for the effective delivery of curcumin (CUR). In the present scenario, the role of nanoparticles in fabricating the DDS is an important one and was characterized using various techniques. The drug loading capacity was high as 89.2% at pH = 8.0, and also the maximum drug release takes place at pH = 5.5. In vitro cell viability studies of DDS on MDA MB-231; breast cancer cells demonstrated its cytotoxicity towards cancer cells. The prepared DDS was also examined for apoptosis, hemocompatibility, and Chorioallantoic membrane (CAM) studies to assess its pharmaceutical field application and the investigation results recommended that it may serve as a potential device for targeted delivery and controlled release of CUR for cancer treatment.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Celulose/síntese química , Curcumina/farmacologia , Portadores de Fármacos , Nanopartículas , Animais , Antineoplásicos Fitogênicos/toxicidade , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Celulose/análogos & derivados , Celulose/toxicidade , Cério/química , Embrião de Galinha , Reagentes para Ligações Cruzadas/química , Curcumina/química , Curcumina/toxicidade , Preparações de Ação Retardada , Composição de Medicamentos , Liberação Controlada de Fármacos , Compostos de Epóxi/química , Feminino , Ácido Fólico/química , Humanos , Concentração de Íons de Hidrogênio , Metacrilatos/química , Sulfatos/química
9.
J Biomater Sci Polym Ed ; 32(11): 1466-1471, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33947317

RESUMO

Polyanions are negatively charged macromolecules known for several decades as inhibitors of many viruses in vitro, notably AIDS virus. In the case of enveloped viruses, this activity was assigned to the formation of a polyelectrolyte complex between an anionic species, the polyanion, and the spike cationic proteins which are, for polymer chemists, comparable to cationic polyelectrolytes. Unfortunately, in vitro antiviral activity was not confirmed in vivo, possibly because polyanions were captured by cationic blood elements before reaching target cells. Accordingly, virologists abandoned the use of polyanions for antiviral therapy. In the case of coronaviruses like SARS-CoV-2 and its mutants the game may not be over because these viruses infect cells of airways and not of blood. This communication proposes strategies to use polysulfates to attack and inhibit viral particles before they reach target cells in the airways. For this, polysulfate solutions may be administered by spray, gargling and nebulization or used to capture virus-containing droplets and aerosols by bubbling when these vectors are in the atmosphere. The technical means exist. However, biocompatibility and biofunctionality tests are necessary in the case of airways. Such tests require manipulation of pathogens, something which is beyond the competences of a biomaterialist. For this, a specialist in virology is necessary. Attempts to find one failed so far despite all-around solicitations over the past ten months and despite the fact that attacking the virus with polysulfates may complement beneficially the defensive strategies based on masks, vaccines and hospitals.


Assuntos
Antivirais/farmacologia , COVID-19/tratamento farmacológico , Polieletrólitos/farmacologia , SARS-CoV-2/efeitos dos fármacos , Sulfatos/farmacologia , Microbiologia do Ar , Antivirais/administração & dosagem , Antivirais/química , COVID-19/prevenção & controle , Humanos , Nebulizadores e Vaporizadores , Sprays Orais , Polieletrólitos/administração & dosagem , Polieletrólitos/química , SARS-CoV-2/genética , Sulfatos/administração & dosagem , Sulfatos/química
10.
Int J Biol Macromol ; 183: 1174-1183, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33984382

RESUMO

Natural active polysaccharides are attracting increased attention from pharmaceutical industries for their valuable biological activities. However, the application of polysaccharides has been restricted due to their relatively large molecular weight, complex structure, and instability. Metal-organic frameworks (MOFs) have emerged to help deliver cargo to specific locations, achieving the objectives of eliminating the potential damage to the body, protecting the drugs, and improving therapeutic effectiveness. Here, a pH-responsive zeolitic imidazolate framework (ZIF-8) was synthesized to encapsulated three sulfated polysaccharides (heparin, fucan sulfate, fucosylated chondroitin sulfate) and a non-sulfated polysaccharide, hyaluronic acid. The resulting polysaccharides@ZIF-8 biocomposites showed differences in terms of morphology, particle size, encapsulation, and release efficiency. These biocomposites retained antithrombotic activity and the framework ZIF-8 effectively protected these polysaccharides from degradation and prolonged shelf-life of the anticoagulants from the unfavorable environment.


Assuntos
Fibrinolíticos/farmacologia , Imidazóis/química , Estruturas Metalorgânicas/química , Polissacarídeos/farmacologia , Sulfatos/química , Sulfatos de Condroitina/química , Sulfatos de Condroitina/farmacologia , Preparações de Ação Retardada , Composição de Medicamentos , Estabilidade de Medicamentos , Fibrinolíticos/química , Heparina/química , Heparina/farmacologia , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Polissacarídeos/química
11.
Molecules ; 26(9)2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33947107

RESUMO

Hemostasis disorders play an important role in the pathogenesis, clinical manifestations, and outcome of COVID-19. First of all, the hemostasis system suffers due to a complicated and severe course of COVID-19. A significant number of COVID-19 patients develop signs of hypercoagulability, thrombocytopenia, and hyperfibrinolysis. Patients with severe COVID-19 have a tendency toward thrombotic complications in the venous and arterial systems, which is the leading cause of death in this disease. Despite the success achieved in the treatment of SARS-CoV-2, the search for new effective anticoagulants, thrombolytics, and fibrinolytics, as well as their optimal dose strategies, continues to be relevant. The wide therapeutic potential of seaweed sulfated polysaccharides (PSs), including anticoagulant, thrombolytic, and fibrinolytic activities, opens up new possibilities for their study in experimental and clinical trials. These natural compounds can be important complementary drugs for the recovery from hemostasis disorders due to their natural origin, safety, and low cost compared to synthetic drugs. In this review, the authors analyze possible pathophysiological mechanisms involved in the hemostasis disorders observed in the pathological progression of COVID-19, and also focus the attention of researchers on seaweed PSs as potential drugs aimed to correction these disorders in COVID-19 patients. Modern literature data on the anticoagulant, antithrombotic, and fibrinolytic activities of seaweed PSs are presented, depending on their structural features (content and position of sulfate groups on the main chain of PSs, molecular weight, monosaccharide composition and type of glycosidic bonds, the degree of PS chain branching, etc.). The mechanisms of PS action on the hemostasis system and the issues of oral bioavailability of PSs, important for their clinical use as oral anticoagulant and antithrombotic agents, are considered. The combination of the anticoagulant, thrombolytic, and fibrinolytic properties, along with low toxicity and relative cheapness of production, open up prospects for the clinical use of PSs as alternative sources of new anticoagulant and antithrombotic compounds. However, further investigation and clinical trials are needed to confirm their efficacy.


Assuntos
Anticoagulantes/farmacologia , COVID-19/complicações , Hemostasia/efeitos dos fármacos , Polissacarídeos/farmacologia , Alga Marinha , Sulfatos/farmacologia , Trombose/complicações , Animais , Anticoagulantes/química , Anticoagulantes/farmacocinética , Anticoagulantes/uso terapêutico , COVID-19/sangue , COVID-19/tratamento farmacológico , Descoberta de Drogas , Humanos , Polissacarídeos/química , Polissacarídeos/farmacocinética , Polissacarídeos/uso terapêutico , Alga Marinha/química , Sulfatos/química , Sulfatos/farmacocinética , Sulfatos/uso terapêutico , Trombose/sangue , Trombose/tratamento farmacológico
12.
Food Chem ; 358: 129908, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33933948

RESUMO

A fucoidan SFP, having novel structure, was extracted from Sargassum fusiforme. It had a molecular weight of 703 kDa and was composed of fucose and galactose with the ratio of 73.16:26.84 (mol%). Structural analyses showed that it mainly consisted of 1,3-, 1,4-, 1,3,4-linked-α-l-Fucp and 1,3-, 1,6-linked-ß-d-Galp, with partial sulfation at C-4, C-3 of fucose units and C-6, C-3 of galactose units. The branches consisted of sulfated fucosyl and galactofucosyl oligosaccharides. The regulatory effects of SFP on the intestinal microbiota in high-fat diet-fed mice were investigated. The high-dosage SFP exhibited good hypolipidemic effects, especially in regulating the high-densitylipoproteincholesterol, non-esterified fatty acid levels and lipase activity. It also significantly decreased the ratio of phyla Firmicutes/Bacteroidetes (P < 0.05). Besides, SFP had certain effects on the richness and diversity of intestinal microbiota. Therefore, SFP exhibited novel structure and certain beneficial effects on the disorder of intestinal microbiota in high-fat diet-fed mice.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Microbioma Gastrointestinal/efeitos dos fármacos , Polissacarídeos/química , Polissacarídeos/farmacologia , Sargassum/química , Animais , Sequência de Carboidratos , Fucose/química , Galactose/química , Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/fisiologia , Hipolipemiantes/química , Hipolipemiantes/farmacologia , Masculino , Camundongos , Peso Molecular , Sulfatos/química
13.
Food Chem ; 361: 130143, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34051596

RESUMO

We previously observed that sialylated bovine milk oligosaccharides (BMOs) decline in both absolute and relative abundances over the initial stages of bovine lactation, with initial evidence suggesting that this decline occurred due to increased concentrations of unique sulfated BMOs. Since both sulfated and sialylated BMOs have distinct bioactivites, a follow up study was launched in order to more clearly define relative changes in these classes of BMOs over the first week of lactation in dairy cattle. Capillary electrophoresis (CE) and several liquid chromatography mass spectrometry (LC-MS) methods, including a novel multiplexed tandem MS method, were used to profile the BMOs extracted from milk collected from the same 20 Holstein cows at milkings 1, 2, 3, 4, 8, and 14 post-partum. In addition to clearly validating that sulfated and sialylated BMOs exist in direct biosynthetic completion, our study has identified over 170 unique BMOs including 14 unique glucuronic acid-containing trisaccharides.


Assuntos
Leite/química , Oligossacarídeos/biossíntese , Oligossacarídeos/química , Animais , Bovinos , Cromatografia Líquida , Eletroforese Capilar , Feminino , Ácido Glucurônico/análise , Ácido Glucurônico/química , Ácido Glucurônico/metabolismo , Glicoconjugados/química , Glicoconjugados/metabolismo , Lactação , Espectrometria de Massas , Leite/metabolismo , Ácido N-Acetilneuramínico/análise , Ácido N-Acetilneuramínico/metabolismo , Oligossacarídeos/análise , Oligossacarídeos/metabolismo , Sulfatos/química
14.
Food Chem ; 361: 130089, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34029907

RESUMO

The polysaccharide of yam was extracted by hot water method and purified by column chromatography. The physicochemical properties of Chinese yam polysaccharide were analyzed by UV, IR, GPC, 1D-NMR and 2D-NMR spectra. The results showed that Chinese yam polysaccharide had α-d-Gluc-(1 â†’ 4) glycoside bond, and the C2 hydroxyl group was replaced by ethoxyl group. The average molecular weight was determined to be 7.28 × 104. It showed that The scavenging effect of yam polysaccharide on hydroxyl radicals was similar to VC. The sulfated polysaccharide (SP), phosphorylated polysaccharide (PP), carboxymethylated polysaccharide (CP) and acetylated polysaccharide (A-P) were identified by IR and NMR. The results showed that P and its derivatives showed good antioxidant activity. Especially, their scavenging ability to hydroxyl radicals reached the level of VC. This laid a theoretical foundation for the development of yam polysaccharide-related foods.


Assuntos
Antioxidantes/química , Dioscorea/química , Polissacarídeos/química , Sequestradores de Radicais Livres/química , Radical Hidroxila/química , Metilação , Peso Molecular , Sulfatos/química
15.
ACS Appl Mater Interfaces ; 13(14): 16084-16096, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33793211

RESUMO

As COVID-19 exemplifies, respiratory diseases transmitted through aerosols or droplets are global threats to public health, and respiratory protection measures are essential first lines of infection prevention and control. However, common face masks are single use and can cause cross-infection due to the accumulated infectious pathogens. We developed salt-based formulations to coat membrane fibers to fabricate antimicrobial filters. Here, we report a mechanistic study on salt-induced pathogen inactivation. The salt recrystallization following aerosol exposure was characterized over time on sodium chloride (NaCl), potassium sulfate (K2SO4), and potassium chloride (KCl) powders and coatings, which revealed that NaCl and KCl start to recrystallize within 5 min and K2SO4 within 15 min. The inactivation kinetics observed for the H1N1 influenza virus and Klebsiella pneumoniae matched the salt recrystallization well, which was identified as the main destabilizing mechanism. Additionally, the salt-coated filters were prepared with different methods (with and without a vacuum process), which led to salt coatings with different morphologies for diverse applications. Finally, the salt-coated filters caused a loss of pathogen viability independent of transmission mode (aerosols or droplets), against both DI water and artificial saliva suspensions. Overall, these findings increase our understanding of the salt-recrystallization-based technology to develop highly versatile antimicrobial filters.


Assuntos
Filtração/instrumentação , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Klebsiella pneumoniae/efeitos dos fármacos , Máscaras , Cloreto de Potássio/química , Cloreto de Sódio/química , Sulfatos/química , Aerossóis , Filtros de Ar , Cristalização , Cinética , Membranas Artificiais , Polipropilenos , Pós , Dispositivos de Proteção Respiratória , Temperatura , Difração de Raios X
16.
Molecules ; 26(8)2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33917913

RESUMO

The metabolism of anthocyanins in humans is still not fully understood, which is partly due to the lack of reference compounds. It is known that sulfation is one way of the complex phase II biotransformation mechanism. Therefore, cyanidin-3-O-glucoside and the cyanidin aglycone were chemically converted to their sulfates by reaction with sulfur trioxide-N-triethylamine complex in dimethylformamide. The reaction products were characterized by UHPLC coupled to linear ion trap and IMS-QTOF mass spectrometry. Based on MS data, retention times, and UV-Vis spectra, the compounds could tentatively be assigned to A-, C-, or B-ring sulfates. Analysis of urine samples from two volunteers after ingestion of commercial blackberry nectar demonstrated the presence of two sulfated derivatives of the cyanidin aglycone and one sulfated derivative of the cyanidin-3-O-glucoside. It was found that both the A ring and the B ring are sulfated by human enzymes. This study marks an important step toward a better understanding of anthocyanin metabolism.


Assuntos
Antocianinas/síntese química , Metaboloma , Sulfatos/síntese química , Antocianinas/química , Antocianinas/urina , Humanos , Projetos Piloto , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Ultravioleta , Sulfatos/química , Sulfatos/urina , Fatores de Tempo
17.
PLoS One ; 16(3): e0241960, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33760840

RESUMO

Diatoms are unicellular photosynthetic algae known to secrete organic matter that fuels secondary production in the ocean, though our knowledge of how their physiology impacts the composition of dissolved organic matter remains limited. Like all photosynthetic organisms, their use of light for energy and reducing power creates the challenge of avoiding cellular damage. To better understand the interplay between redox balance and organic matter secretion, we reconstructed a genome-scale metabolic model of Thalassiosira pseudonana strain CCMP 1335, a model for diatom molecular biology and physiology, with a 60-year history of studies. The model simulates the metabolic activities of 1,432 genes via a network of 2,792 metabolites produced through 6,079 reactions distributed across six subcellular compartments. Growth was simulated under different steady-state light conditions (5-200 µmol photons m-2 s-1) and in a batch culture progressing from exponential growth to nitrate-limitation and nitrogen-starvation. We used the model to examine the dissipation of reductants generated through light-dependent processes and found that when available, nitrate assimilation is an important means of dissipating reductants in the plastid; under nitrate-limiting conditions, sulfate assimilation plays a similar role. The use of either nitrate or sulfate uptake to balance redox reactions leads to the secretion of distinct organic nitrogen and sulfur compounds. Such compounds can be accessed by bacteria in the surface ocean. The model of the diatom Thalassiosira pseudonana provides a mechanistic explanation for the production of ecologically and climatologically relevant compounds that may serve as the basis for intricate, cross-kingdom microbial networks. Diatom metabolism has an important influence on global biogeochemistry; metabolic models of marine microorganisms link genes to ecosystems and may be key to integrating molecular data with models of ocean biogeochemistry.


Assuntos
Diatomáceas/metabolismo , Genoma , Nitrogênio/metabolismo , Enxofre/metabolismo , Trifosfato de Adenosina/metabolismo , Biomassa , Diatomáceas/genética , Diatomáceas/crescimento & desenvolvimento , Diatomáceas/efeitos da radiação , Luz , Análise do Fluxo Metabólico , Mitocôndrias/metabolismo , Nitratos/química , Nitratos/metabolismo , Nitrogênio/química , Oxirredução , Sulfatos/química , Sulfatos/metabolismo , Enxofre/química
18.
PLoS One ; 16(3): e0243444, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33784303

RESUMO

A novel isolated strain Acidithiobacillus ferrooxidans BMSNITK17 has been investigated for its bioleaching potential from lateritic soil and the results are presented. System conditions like pH, feed mineral particle size, pulp density, temperature, rotor speed influences bioleaching potential of Acidithiobcillus ferrooxidans BMSNITK17 in leaching out iron from laterite soil. Effect of sulfate addition on bioleaching efficiency is studied. The bioleached laterite iron (BLFe's) on evaluation for its catalytic role in Fenton's oxidation for the degradation of ametryn and dicamba exhibits 94.24% of ametryn degradation and 92.45% of dicamba degradation efficiency. Fenton's oxidation performed well with the acidic pH 3. The study confirms the role of Acidithiobacillus ferrooxidans in leaching iron from lateritic ore and the usage of bioleached lateritic iron as catalyst in the Fenton's Oxidation.


Assuntos
Acidithiobacillus/metabolismo , Herbicidas/química , Peróxido de Hidrogênio/química , Ferro/química , Solo/química , Acidithiobacillus/química , Biodegradação Ambiental , Catálise , Herbicidas/metabolismo , Concentração de Íons de Hidrogênio , Minerais/química , Oxirredução , Tamanho da Partícula , Sulfatos/química , Temperatura
19.
Biomed Pharmacother ; 138: 111459, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33706132

RESUMO

Silymarin is a mixture of flavonolignans isolated from the fruit of milk thistle (Silybum marianum (L.) Gaertner). Milk thistle extract is the active ingredient of several medications and dietary supplements to treat liver injury/diseases. After the oral administration, flavonolignans are extensively biotransformed, resulting in the formation of sulfate and/or glucuronide metabolites. Previous studies demonstrated that silymarin components form stable complexes with serum albumin and can inhibit certain cytochrome P450 (CYP) enzymes. Nevertheless, in most of these investigations, silybin was tested; while no or only limited information is available regarding other silymarin components and metabolites. In this study, the interactions of five silymarin components (silybin A, silybin B, isosilybin A, silychristin, and 2,3-dehydrosilychristin) and their sulfate metabolites were examined with human serum albumin and CYP (2C9, 2C19, 2D6, and 3A4) enzymes. Our results demonstrate that each compound tested forms stable complexes with albumin, and certain silymarin components/metabolites can inhibit CYP enzymes. Most of the sulfate conjugates were less potent inhibitors of CYP enzymes, but 2,3-dehydrosilychristin-19-O-sulfate showed the strongest inhibitory effect on CYP3A4. Based on these observations, the simultaneous administration of high dose silymarin with medications should be carefully considered, because milk thistle flavonolignans and/or their sulfate metabolites may interfere with drug therapy.


Assuntos
Citocromo P-450 CYP2C19/metabolismo , Citocromo P-450 CYP2C9/metabolismo , Citocromo P-450 CYP2D6/metabolismo , Citocromo P-450 CYP3A/metabolismo , Albumina Sérica Humana/metabolismo , Silimarina/metabolismo , Relação Dose-Resposta a Droga , Interações Medicamentosas/fisiologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Ligação Proteica/fisiologia , Silimarina/química , Silimarina/farmacologia , Sulfatos/química , Sulfatos/metabolismo , Sulfatos/farmacologia
20.
J Oleo Sci ; 70(3): 363-374, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33658467

RESUMO

The physicochemical properties of cetyltrimethylammonium bromide (CTAB) in pure water and ethanol-water mixtures in the presence and absence of MnSO4.6H2O were studied by measuring the conductivity at room temperature. The concentration range of CTAB was ~1.00 × 10-5 M to ~1.00 × 10-2M and the concentration of MnSO4.6H2O was 0.001 M, 0.005 M, 0.01 M. With increasing ethanol content in the solvent composition, the critical micelle concentration (CMC) and the degree of micellar dissociation (α) of CTAB increased. With the help of CMC and α, the standard free energy of micellization (ΔG m ο ) was evaluated. With an increase in ethanol content, the negative values of ΔG m ο decreased. CTAB micellization was tested in the context of specific solvent parameters. The solvent conductivity ratio at CMC to limiting conductivity was employed as a solvophobic influence. The addition of salt (MnSO4.6H2O) decreases the CMC of CTAB due to the screening of the electrostatic repulsion of the head groups. Here, we report that micellization is strongly influenced by salt concentration.


Assuntos
Cetrimônio/química , Etanol/química , Compostos de Manganês/química , Solventes/química , Sulfatos/química , Termodinâmica , Água/química , Micelas , Eletricidade Estática , Tensoativos/química
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