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1.
Small ; 20(4): e2305782, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37718497

RESUMO

Due to their unique electronic and structural properties, single-atom catalytic materials (SACMs) hold great promise for the oxygen reduction reaction (ORR). Coordinating environmental and engineering strategies is the key to improving the ORR performance of SACMs. This review summarizes the latest research progress and breakthroughs of SACMs in the field of ORR catalysis. First, the research progress on the catalytic mechanism of SACMs acting on ORR is reviewed, including the latest research results on the origin of SACMs activity and the analysis of pre-adsorption mechanism. The study of the pre-adsorption mechanism is an important breakthrough direction to explore the origin of the high activity of SACMs and the practical and theoretical understanding of the catalytic process. Precise coordination environment modification, including in-plane, axial, and adjacent site modifications, can enhance the intrinsic catalytic activity of SACMs and promote the ORR process. Additionally, several engineering strategies are discussed, including multiple SACMs, high loading, and atomic site confinement. Multiple SACMs synergistically enhance catalytic activity and selectivity, while high loading can provide more active sites for catalytic reactions. Overall, this review provides important insights into the design of advanced catalysts for ORR.

2.
Int J Mol Sci ; 25(4)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38396723

RESUMO

The water and ethanol extracts of huangqin, the roots of Scutellaria baicalensis Georgi. with potential antiviral properties and antioxidant activities, were investigated for their chemical profiles and their abilities to interfere with the interaction between SARS-CoV-2 spike protein and ACE2, inhibiting ACE2 activity and scavenging free radicals. A total of 76 compounds were tentatively identified from the extracts. The water extract showed a greater inhibition on the interaction between SARS-CoV-2 spike protein and ACE2, but less inhibition on ACE2 activity than that of the ethanol extract on a per botanical weight concentration basis. The total phenolic content was 65.27 mg gallic acid equivalent (GAE)/g dry botanical and the scavenging capacities against HO●, DPPH●, and ABTS●+ were 1369.39, 334.37, and 533.66 µmol trolox equivalent (TE)/g dry botanical for the water extract, respectively. These values were greater than those of the ethanol extract, with a TPC of 20.34 mg GAE/g, and 217.17, 10.93, and 50.21 µmol TE/g against HO●, DPPH●, and ABTS●+, respectively. The results suggested the potential use of huangqin as a functional food ingredient in preventing COVID-19.


Assuntos
Benzotiazóis , COVID-19 , Scutellaria baicalensis , Ácidos Sulfônicos , Humanos , Scutellaria baicalensis/química , Glicoproteína da Espícula de Coronavírus , Enzima de Conversão de Angiotensina 2 , SARS-CoV-2 , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Radicais Livres , Etanol , Água
3.
Small ; 19(43): e2303031, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37356067

RESUMO

Bimetallic Nanoalloy catalysts have diverse uses in clean energy, sensing, catalysis, biomedicine, and energy storage, with some supported and unsupported catalysts. Conventional synthetic methods for producing bimetallic alloy nanoparticles often produce unalloyed and bulky particles that do not exhibit desired characteristics. Alloys, when prepared with advanced nanoscale methods, give higher surface area, activity, and selectivity than individual metals due to changes in their electronic properties and reduced size. This review demonstrates the synthesis methods and principles to produce and characterize highly dispersed, well-alloyed bimetallic nanoalloy particles in relatively simple, effective, and generalized approaches and the overall existence of conventional synthetic methods with modifications to prepare bimetallic alloy catalysts. The basic concepts and mechanistic understanding are represented with purposely selected examples. Herein, the enthralling properties with widespread applications of nanoalloy catalysts in heterogeneous catalysis are also presented, especially for Hydrogen Evolution Reaction (HER), Oxidation Reduction Reaction (ORR), Oxygen Evolution Reaction (OER), and alcohol oxidation with a particular focus on Pt and Pd-based bimetallic nanoalloys and their numerous fields of applications. The high entropy alloy is described as a complicated subject with an emphasis on laser-based green synthesis of nanoparticles and, in conclusion, the forecasts and contemporary challenges for the controlled synthesis of nanoalloys are addressed.

4.
Small ; : e2305405, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38072804

RESUMO

As the cleanest energy source, hydrogen has been followed with interest by researchers around the world. However, due to the internal low density of hydrogen, it cannot be stored and used efficiently which limits the hydrogen application on a huge scale. Chemical hydrogen storage is considered as a useful method for efficient handling and storage. Due to its excellent safety, formic acid stands out. It is worth noting that the matter and energy conversion is established based on formic acid, which is not referred to in the previous documentation. In this review, the latest development of research on heterogeneous catalysis via production and application of formic acid for energy application is reported. The matter and energy conversion based on formic acid are both discussed systematically. More importantly, with formic acid as the node, biomass energy shows potential to be in a dominant position in the energy conversion process. In addition, the catalytic mechanism is also mentioned. This review can provide the current state in this field and the new inspirations for developing superior catalytic systems.

5.
Small ; : e2307662, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38072770

RESUMO

The problem in d-band center modulation of transition metal-based catalysts for the rate-determining steps of oxygen conversion is an obstacle to boost the electrocatalytic activity by accelerating proton coupling. Herein, the Co doping to FeP is adopted to modify the d-band center of Fe. Optimized Fe sites accelerate the proton coupling of oxygen reduction reaction (ORR) on N-doped wood-derived carbon through promoting water dissociation. In situ generated Fe sites optimize the adsorption of oxygen-related intermediates of oxygen evolution reaction (OER) on CoFeP NPs. Superior catalytic activity toward ORR (half-wave potential of 0.88 V) and OER (overpotential of 300 mV at 10 mA cm-2 ) express an unprecedented level in carbon-based transition metal-phosphide catalysts. The liquid zinc-air battery presents an outstanding cycling stability of 800 h (2400 cycles). This research offers a newfangled perception on designing highly efficient carbon-based bifunctional catalysts for ORR and OER.

6.
Mol Cell Biochem ; 478(6): 1397-1410, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36378463

RESUMO

The inflammasome is a multimeric protein complex located in the cytoplasm that is activated by many factors and subsequently promotes the release of proinflammatory factors such as interleukin (IL)-1ß and IL-18, resulting in a series of inflammatory responses that ultimately lead to the occurrence of various diseases. The Nod-like receptor protein 3 (NLRP3) inflammasome is the most characteristic type and the most widely studied among many inflammasomes. Activation of the NLRP3 inflammasome is closely related to the occurrence of many diseases, such as Alzheimer's disease. At present, a large number of studies have focused on the mechanisms underlying the activation of the NLRP3 inflammasome. Plenty of articles have reported the activation of the NLRP3 inflammasome by various ions, such as K+ and Na+ reflux and Ca2+ influx. However, few articles have reviewed the effects of various ion channels on the activation of the NLRP3 inflammasome and the relationship between the diseases caused by these proteins. This article mainly summarizes the relationship between intracellular and extracellular ion activities and ion channels and the activation of the NLRP3 inflammasome. We also provide a general summary of the diseases of each system caused by NLRP3 activation. We hope that more research will provide options for the treatment of diseases driven by the NLRP3 inflammasome.


Assuntos
Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas NLR , Interleucina-1beta/metabolismo
7.
Exp Cell Res ; 417(2): 113227, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35644413

RESUMO

Chili pepper and its major active compound capsaicin have long been used not only a daily food additive but also medication worldwide. Like in other human organs and systems, capsaicin has multiple actions in gastrointestinal (GI) physiology and pathology. Numerous studies have revealed that capsaicin acts on GI tract in TRPV1-dependent and -independent manners, mostly depending on its consumption concentrations. In this review, we will focus on the beneficial role of capsaicin in GI tract, a less highlighted aspect, in particular how dietary capsaicin affects GI health, the mechanisms of actions and its preventive/therapeutic potentials to several GI diseases. Dietary capsaicin affects GI tract not only via TRPV1-derpendent and independent manners, but also via acute and chronic effects. Although high dose intake of dietary capsaicin is harmful to human health sometimes, current literatures suggest that appropriate dose intake is likely beneficial to GI health and is preventive/therapeutic to GI disease in most cases as well. With extensive and intensive studies on its GI actions, capsaicin, as a daily consumed food additive, has potential to become a safe drug for the treatment of several GI diseases.


Assuntos
Capsaicina , Trato Gastrointestinal , Capsaicina/farmacologia , Capsaicina/uso terapêutico , Dieta , Aditivos Alimentares/farmacologia , Humanos , Canais de Cátion TRPV/fisiologia
8.
Small ; 18(34): e2202725, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35871557

RESUMO

Oxygen reduction reaction (ORR) is the key reaction on cathode of rechargeable zinc-air batteries (ZABs). However, the lack of protons in alkaline conditions limits the rate of ORR. Herein, an activating water strategy is proposed to promote oxygen electrocatalytic activity by enhancing the proton production from water dissociation. FeP nanoparticles (NPs) are coupled on N-doped wood-derived catalytically active carbon (FeP-NWCC) to associate bifunctional active sites. In alkaline, FeP-NWCC possesses outstanding catalytic activities toward ORR (E1/2  = 0.86 V) and Oxygen evolution reaction (OER) (overpotential is 310 mV at 10 mA cm-2 ). The liquid ZABs assembled by FeP-NWCC deliver superior peak power density (144 mW cm-2 ) and cycle stability (over 450 h). The quasi-solid-state ZABs based on FeP-NWCC also display excellent performances. Theoretical calculation illustrates that the superb bifunctional performance of FeP-NWCC results from the elevated dissociation efficiency of water via FeP NPs to assist the oxygen catalytic process. The strategy of activating water provides a new perspective for the design of ORR/OER bifunctional catalysts. This work is a model for the application of forest biomass.


Assuntos
Oxigênio , Água , Catálise , Fontes de Energia Elétrica , Oxigênio/química , Prótons , Madeira , Zinco/química
9.
Small ; 18(8): e2105588, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34889521

RESUMO

Water dissociation is the rate-limiting step of several energy-related reactions due to the high energy barrier required for breaking the oxygen-hydrogen bond. In this work, a bimodal oxygen vacancy (VO ) catalysis strategy is adopted to boost the efficient water dissociation on Pt nanoparticles. The single facet-exposed TiO2 surface and NiOx nanocluster possess two modes of VO different from each other. In ammonia borane hydrolysis, the highest catalytic activity among Pt-based materials is achieved with the turnover frequency of 618 min-1 under alkaline-free conditions at 298 K. Theoretical simulation and characterization analyses reveal that the bimodal VO significantly promotes the water dissociation in two ways. First, an ensemble-inducing effect of Pt and VO in TiO2 drives the activation of water molecules. Second, an electron promoter effect induced by the electron transfer from VO in NiOx to Pt further enhances the ability of Pt to dissociate water and ammonia borane. This insight into bimodal VO catalysis establishes a new avenue to rationally design heterogeneous catalytic materials in the energy chemistry field.


Assuntos
Oxigênio , Água , Amônia , Catálise , Ligação de Hidrogênio , Oxigênio/química
10.
Small ; 18(26): e2202014, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35644887

RESUMO

Electrochemical reduction of oxygen plays a critical role in emerging electrochemical energy technologies. Multiple electron transfer processes, involving adsorption and activation of O2 and generation of protons from water molecules, cause the sluggish kinetics of the oxygen reduction reaction (ORR). Herein, a double-active-site catalyst of Fe3 C nanoparticles coupled to paulownia wood-derived N-doped carbon (Fe3 C@NPW) is fabricated via an active-site-uniting strategy. One site on Fe3 C nanoparticles contributes to activating water molecules, while another site on N-doped carbon is responsible for activating oxygen molecules. Benefiting from the synergistic effect of double active sites, Fe3 C@NPW delivers a remarkable catalytic activity for ORR with a half-wave potential of 0.87 V (vs. RHE) in alkaline electrolyte, outperforming commercial Pt/C catalyst. Moreover, zinc-air batteries (ZABs) assembled with Fe3 C@NPW as a catalyst on cathode achieve a large specific capacity of 804.4 mA h gZn-1 and a long-term stability of 780 cycles. The model solid-state ZABs also display satisfactory performances with an open-circuit voltage of 1.39 V and a high peak power density of 78 mW cm-2 . These outstanding performances reach the level of first-rank among the non-noble metal electrode materials. This work offers a promising approach to creating double-active-site catalysts by the active-site-uniting strategy for energy conversion fields.


Assuntos
Carbono , Nanopartículas , Eletrodos , Hipóxia , Oxigênio , Água , Madeira , Zinco
11.
Small ; 18(22): e2107417, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35508765

RESUMO

The rational design of the interface structure between nitride and oxide using the same metallic element and correlating the interfacial active center with a determined catalytic mechanism remain challenging. Herein, a Co4 N-Co3 O4 interface structure is designed to determine the effect of interfacial active centers on hydrogen generation from ammonia borane. An unparalleled catalytic activity toward H2 production with a turnover frequency up to 79 min-1 is achieved on Co4 N-Co3 O4 @C catalyst for ten recycles. Experimental analyses and theoretical simulation suggest that the atomic interface-exciting effect (AieE) is responsible for the high catalytic activity. The Co4 N-Co3 O4 interface facilitates the targeted adsorption and activation of NH3 BH3 and H2 O molecules to generate H* and H2 . The two active centers of Co(N)* and Co(O)* at the Co4 N-Co3 O4 interface activate NH3 BH3 and H2 O, respectively. This proof-of-concept research on AieE provides important insights regarding the design of heterogeneous catalysts and promotes the development of the nature and regulation of energy chemical conversion.


Assuntos
Cobalto , Óxidos , Amônia , Catálise , Cobalto/química , Hidrogênio/química , Óxidos/química
12.
Respiration ; 101(7): 683-687, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35576895

RESUMO

Transbronchial mediastinal cryobiopsy is a novel sampling strategy that shows improved diagnostic utility for mediastinal lesions, particularly in rare tumors and benign disorders, as compared to standard endobronchial ultrasound-guided transbronchial needle aspiration. During this procedure, electrocautery incision is frequently needed to advance the cryoprobe through the airway into the mediastinal lesion, which however results in increased operative difficulty and prolonged procedural time. Here we present a case of mediastinal large B-cell lymphoma successfully diagnosed by transbronchial mediastinal cryobiopsy without cautery-induced airway incision.


Assuntos
Broncoscopia , Linfoma de Células B , Broncoscopia/métodos , Eletrocoagulação , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Humanos , Linfonodos/patologia , Linfoma de Células B/diagnóstico , Linfoma de Células B/cirurgia , Mediastino/diagnóstico por imagem
13.
Respiration ; 101(2): 190-194, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34515245

RESUMO

Guidelines have recommended endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and endoscopic ultrasound-guided fine-needle aspiration biopsy as initial sampling approaches of mediastinal lymph nodes for lung cancer staging. However, the small sample volume might restrict the diagnostic utility of needle aspiration in certain mediastinal diseases. We have recently shown that transbronchial mediastinal cryobiopsy, which is capable of providing larger amounts of intact tissue, improves diagnostic yield in rare tumors and benign diseases compared to EBUS-TBNA. Here, we present a case of mediastinal nodular lymphocyte predominant Hodgkin lymphoma successfully diagnosed by endoscopic transesophageal cryobiopsy.


Assuntos
Doença de Hodgkin , Neoplasias Pulmonares , Broncoscopia , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Endossonografia , Doença de Hodgkin/diagnóstico , Doença de Hodgkin/patologia , Humanos , Neoplasias Pulmonares/patologia , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Linfócitos , Mediastino , Estadiamento de Neoplasias
14.
Respiration ; 101(10): 948-952, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36007500

RESUMO

Mediastinal abscess, mostly resulting from esophageal perforation or cardiothoracic surgery, is a serious condition carrying high morbidity and mortality. Antibiotic therapy alone normally did not achieve a satisfactory outcome, due to poor circulation of abscess that hampers drug delivery. Surgical intervention for debridement and drainage is recommended, but it poses a high risk in patients with poor health status and could lead to various complications. Recent studies proposed endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) as an effective alternative to surgery; however, repeated TBNA procedures are usually needed for complete clearance of the lesion, thus causing increased patient suffering and medical expenses. Here, we present the first case of successful application of EBUS-guided transbronchial incision and drainage, which provides a novel, safe, and effective treatment for patient with mediastinal abscess unwilling or unsuitable to undergo surgical intervention.


Assuntos
Neoplasias Pulmonares , Doenças do Mediastino , Abscesso/diagnóstico por imagem , Abscesso/tratamento farmacológico , Abscesso/cirurgia , Antibacterianos/uso terapêutico , Broncoscopia/métodos , Drenagem , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Humanos , Neoplasias Pulmonares/patologia , Doenças do Mediastino/diagnóstico por imagem , Doenças do Mediastino/cirurgia
15.
Eur Respir J ; 58(6)2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33958432

RESUMO

BACKGROUND: Guidelines recommend endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) as an initial investigatory technique for mediastinal nodal staging in lung cancer. However, EBUS-TBNA can be limited by the inadequacy of intact tissues, which might restrict its diagnostic yield in mediastinal lesions of certain aetiologies. We have previously shown that EBUS-guided transbronchial mediastinal cryobiopsy can provide intact samples with greater volume. METHODS: This randomised study determined the diagnostic yield and safety of transbronchial mediastinal cryobiopsy monitored by endosonography for the diagnosis of mediastinal lesions. Patients with a mediastinal lesion of ≥1 cm in the short axis were recruited. Following identification of the mediastinal lesion by linear EBUS, fine-needle aspiration and cryobiopsy were sequentially performed in a randomised order. Primary end-points were diagnostic yield, defined as the percentage of patients for whom mediastinal biopsy provided a definite diagnosis, and procedure-related adverse events. RESULTS: In total, 197 patients were enrolled and randomly allocated. The overall diagnostic yield was 79.9% and 91.8% for TBNA and transbronchial mediastinal cryobiopsy, respectively (p=0.001). Diagnostic yields were similar for metastatic lymphadenopathy (94.1% versus 95.6%, p=0.58), while cryobiopsy was more sensitive than TBNA in uncommon tumours (91.7% versus 25.0%, p=0.001) and benign disorders (80.9% versus 53.2%, p=0.004). No significant differences in diagnostic yield were detected between "TBNA first" and "Cryobiopsy first" groups. We observed two cases of pneumothorax and one case of pneumomediastinum. CONCLUSIONS: Transbronchial cryobiopsy performed under EBUS guidance is a safe and useful approach that offers diagnostic histological samples of mediastinal lesions.


Assuntos
Broncoscopia , Neoplasias Pulmonares , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Endossonografia , Humanos , Neoplasias Pulmonares/diagnóstico , Linfonodos , Mediastino , Estudos Retrospectivos
16.
Small ; 17(38): e2101607, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34365727

RESUMO

Zinc-air batteries (ZABs) are promising as energy storage devices owing to their high energy density and the safety of electrolytes. Construction of abundant triple-phase boundary (TPB) effectively facilitates cathode reactions occurring at TPB. Herein, a wood-derived integral air electrode containing Co/CoO nanoparticles and nitrogen-doped carbonized wood (Co/CoO@NWC) is constructed with a dual catalytic function. The potential gap between oxygen reduction and evolution is shortened to 0.77 V. Liquid ZABs using Co/CoO@NWC as cathode exhibit high discharge specific capacity (800 mAh gZn-1 ), low charge-discharge gap (0.84 V), and long-term cycling stability (270 h). Co/CoO@NWC also shows distinguished catalytic activity and stability in all-solid-state ZABs. The inherent layered porous and pipe structures of wood are well maintained in catalytically active carbon. The different hydrophilicity of carbonized wood and Co/CoO endow abundant TPBs for battery reaction. The Co/CoO located on TPB provides main active sites for oxygen reactions. The inherent pipe structures of wood carbon and the interaction between Co/CoO and NWC effectively prevent nanoparticles from aggregation. The design and preparation of this monolithic electrocatalyst contribute to the broad-scale application of ZABs and promote the development of next-generation biomass-based storage devices.


Assuntos
Madeira , Zinco , Carbono , Fontes de Energia Elétrica , Eletrodos
17.
Small ; 17(52): e2102201, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34396693

RESUMO

Hydrogen is a clean and sustainable energy carrier, which is considered a promising alternative for fossil fuels to solve the global energy crisis and respond to climate change. Social concerns on its safe storage promote continuous exploration of alternatives to traditional storage methods. In this case, chemical hydrogen storage materials initiate plentiful research with special attention to the design of heterogeneous catalysts that can enhance efficient and highly selective hydrogen production. Metal-organic frameworks (MOFs), a kind of unique crystalline porous materials featuring highly ordered porosities and tailorable structures, can provide various active sites (i.e., metal nodes, functional linkers, and defects) for heterogeneous catalysis. Furthermore, the easy construction of active sites in highly ordered MOFs, which can work as plate for the delicate active site engineering, make them ideal candidates for a variety of heterogeneous catalysts including chemocatalytic hydrogen production. This review concentrates on the application of MOFs as heterogeneous catalysts or catalyst supports in chemocatalytic hydrogen production. Recent progresses of MOFs as catalysts for chemocatalytic hydrogen production are comprehensively summarized. The research methods, mechanism analyses, and prospects of MOFs in this field are discussed. The challenges in future industrial applications of MOFs as catalysts for hydrogen production are proposed.


Assuntos
Estruturas Metalorgânicas , Catálise , Hidrogênio , Metais
18.
Anal Bioanal Chem ; 412(15): 3653-3662, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32322951

RESUMO

Cranberry proanthocyanidin oligomers were investigated using ultra performance liquid chromatography-ion mobility-high-resolution mass spectrometry (UPLC-IM-HRMS). A total of 304 individual A-type and B-type proanthocyanidins, including 40 trimers, 68 tetramers, 53 pentamers, 54 hexamers, 49 heptamers, 28 octamers, and 12 nonamers, were characterized. A-type proanthocyanidins appeared to dominate the cranberry proanthocyanidins. As the degree of polymerization increased, the abundance of molecules with multiple A-type double inter-flavan linkage or having doubly charged ions also increased. Under the same charge state, the drift times of proanthocyanidin ions increased with their degree of polymerization or the number of double inter-flavan linkages. For the same proanthocyanidin molecules, doubly charged ions had shorter drift times compared to their singly charged counterparts, which lead to separated trendlines in the ion mobility-mass plot. While consistent ion mobility was observed for most proanthocyanidins with the same degree of polymerization, coeluted isomeric ions of trimer and tetramer were detected by their unique drift times. Incorporation of ion mobility into HRMS proved to be of great value to characterize and analyze proanthocyanidins from complex sample matrices. Graphical abstract.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Proantocianidinas/análise , Vaccinium macrocarpon/química , Dimerização , Espectrometria de Mobilidade Iônica/métodos , Extratos Vegetais/química
19.
Phytochem Anal ; 31(6): 874-883, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32472622

RESUMO

INTRODUCTION: American cranberries (Vaccinium macrocarpon) contain primarily A-type proanthocyanidins (PACs), which have been shown to prevent urinary tract infection. Currently, the accurate quantification of cranberry PACs is still lacking. OBJECTIVE: A normal-phase high-performance liquid chromatography (NP-HPLC) method using relative response factors was developed and validated to quantify cranberry PAC oligomers and polymers. MATERIALS AND METHODS: PAC oligomers with degree of polymerisation (DP) 3-9 and total polymers were isolated from the cranberry juice concentrate. Characterisation of the isolated PAC oligomers was performed by ultra-performance liquid chromatography-high resolution mass spectrometry. The relative response factors of oligomers from DP 2-9 and total polymers were determined against procyanidin A2. Method validation was conducted to assess limit of detection, limit of quantification, the linearity and working range, precision and accuracy. In addition, quantifications of PACs by NP-HPLC using relative response factors and two other commonly used methods were conducted in three cranberry food products. RESULTS: Cranberries PACs oligomers contained both A-type and B-type linkage, with epicatechin and epigallocatechin as basic units. Method validation results suggested this method is reliable and reproducible. Quantifications of PACs by NP-HPLC using relative response factors yielded higher values than that by the other two methods. CONCLUSION: A NP-HPLC method using the relative response factors was developed and validated. This method provides a more accurate approach in determining cranberry PACs. It can be used to quantify individual oligomers from DP 2-9, total polymers and total PACs in cranberries and cranberry products.


Assuntos
Proantocianidinas , Vaccinium macrocarpon , Cromatografia Líquida de Alta Pressão , Família , Frutas/química , Extratos Vegetais , Proantocianidinas/análise
20.
J Nutr ; 146(12): 2491-2496, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27798348

RESUMO

BACKGROUND: We previously reported that dietary intake of shiitake mushroom (SM; Lentinus edodes) decreased serum concentrations of polar lipids in male rats. OBJECTIVE: This study evaluated the dietary effects of SM on serum cholesterol-related and serum antioxidant indexes in rats of both sexes. METHODS: Sprague-Dawley rats [38 dams and their offspring (20 males and 20 females/diet)] were fed diets containing 0 (control), 1%, 4%, or 10% (wt:wt) SM powder from gestation day 4 through to postnatal day (PND) 126. Biochemical indexes were monitored during the midgrowth phase (PNDs 50-66). RESULTS: The food consumption by offspring fed the control diet and diets supplemented with SM was not different when measured on PND 65. However, the 4% and 10% SM diets resulted in male rats with 7% lower body weights than those of the other 2 groups on PND 66. SM consumption dose-dependently decreased the concentrations of lipidemia-related factors in sera, irrespective of sex. At PND 50, serum concentrations of total cholesterol, HDL cholesterol, and non-HDL cholesterol in SM-fed male and female rats were generally lower (3-27%) than those in the corresponding control groups. Consumption of the 10% SM diet resulted in significantly decreased (55%) serum triglyceride concentrations relative to the control groups for both sexes. The 10% SM diet elicited a 62% reduction of serum leptin concentrations in females but not in males, and this same diet increased serum insulin (137%) and decreased serum glucose (15%) in males compared with controls. Serum lipophilic antioxidant capacity in males and females fed SM diets was generally lower (31-86%) than that in the control groups. CONCLUSION: SM decreased the concentrations of lipidemia-related factors in rat sera irrespective of sex. The SM-elicited reduction of lipophilic antioxidant capacity irrespective of sex may reflect a lower pro-oxidative state and, hence, improved metabolic profile.


Assuntos
Antioxidantes/metabolismo , Lipídeos/sangue , Fenômenos Fisiológicos da Nutrição Materna , Cogumelos Shiitake , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta , Relação Dose-Resposta a Droga , Feminino , Hiperlipidemias/metabolismo , Insulina/sangue , Leptina/sangue , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
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