Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Molecules ; 29(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38611855

RESUMO

Quinoa, known as the "golden grain" for its high nutritional value, has polysaccharides as one of its sources of important nutrients. However, the biological functions of quinoa polysaccharides remain understudied. In this study, two crude polysaccharide extracts of quinoa (Q-40 and Q-60) were obtained through sequential precipitation with 40% and 60% ethanol, with purities of 58.29% (HPLC) and 62.15% (HPLC) and a protein content of 8.27% and 9.60%, respectively. Monosaccharide analysis revealed that Q-40 contained glucose (Glc), galacturonic acid (GalA), and arabinose (Ara) in a molar ratio of 0.967:0.027:0.006. Q-60 was composed of xylose (xyl), arabinose (Ara), galactose, and galacturonic acid (GalA) with a molar ratio of 0.889:0.036:0.034:0.020. The average molecular weight of Q-40 ranged from 47,484 to 626,488 Da, while Q-60 showed a range of 10,025 to 47,990 Da. Rheological experiments showed that Q-40 exhibited higher viscosity, while Q-60 demonstrated more elastic properties. Remarkably, Q-60 showed potent antioxidant abilities, with scavenging rates of 98.49% for DPPH and 57.5% for ABTS. Antibacterial experiments using the microdilution method revealed that Q-40 inhibited the growth of methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli), while Q-60 specifically inhibited MRSA. At lower concentrations, both polysaccharides inhibited MDA (MD Anderson Cancer Center) cell proliferation, but at higher concentrations, they promoted proliferation. Similar proliferation-promoting effects were observed in HepG2 cells. The research provides important information in the application of quinoa in the food and functional food industries.


Assuntos
Chenopodium quinoa , Ácidos Hexurônicos , Staphylococcus aureus Resistente à Meticilina , Arabinose , Escherichia coli , Grão Comestível
2.
Int J Biol Macromol ; 258(Pt 2): 128833, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38128806

RESUMO

Natural polysaccharides exhibit numerous beneficial properties, such as antioxidant, antitumor, hypoglycemic, and hypolipidemic activities. Moringa oleifera seeds are of high dietary and therapeutic value which drew a lot of attention. However, the regulation effect on anti-inflammatory activity of polysaccharides remains to be studied. Herein, novel bioactive polysaccharides (MOSP-1) were extracted from Moringa oleifera seeds, and the anti-inflammatory properties of MOSP-1 were uncovered. Ultrasound-assisted extraction (UAE) was used to prepare the polysaccharides with optimized conditions (70 °C, 43 min, and liquid-solid-ratio 15 mL/g). Then, DEAE-Sepharose Fast Flow columns were applied to isolate and purify MOSP-1. Rhamnose, arabinose, galactose, and glucose were identified as the monosaccharide constituents of MOSP-1, with a molecular weight of 5.697 kDa. Their proportion in molarity was 1:0.183:0.108:0.860 and 8 types of glycosidic linkages were discovered. Bioactive assays showed that MOSP-1 possessed scavenging activities against DPPH and ABTS radicals, confirming its potential antioxidation efficacy. In vitro experiments revealed that MOSP-1 could reduce the expression of inflammation-related cytokines, inhibit the activation of ERK, JNK, and p38 (the MAPK signaling pathway), and enhance phagocytic functions. This study indicates that polysaccharides (MOSP-1) from Moringa oleifera seeds with anti-inflammatory properties may be used for functional food and pharmaceutical product development.


Assuntos
Moringa oleifera , Moringa oleifera/química , Ultrassom , Polissacarídeos/química , Antioxidantes/química , Anti-Inflamatórios , Sementes/química
3.
Front Nutr ; 10: 1158158, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37090775

RESUMO

Cyclocarya paliurus (C. paliurus), a nutritional and nutraceutical resource for human and animal diets, has been constantly explored. The available biological components of C. paliurus were triterpenoids, polysaccharides, and flavonoids. Recent studies in phytochemical-phytochemistry; pharmacological-pharmacology has shown that C. paliurus performed medicinal value, such as antihypertensive, antioxidant, anticancer, antimicrobial, anti-inflammatory and immunological activities. Furthermore, C. paliurus and its extracts added to drinks would help to prevent and mitigate chronic diseases. This review provides an overview of the nutritional composition and functional applications of C. paliurus, summarizing the research progress on the extraction methods, structural characteristics, and biological activities. Therefore, it may be a promising candidate for developing functional ingredients in traditional Chinese medicine. However, a more profound understanding of its active compounds and active mechanisms through which they perform biological activities is required. As a result, the plant needs further investigation in vitro and in vivo.

4.
J Agric Food Chem ; 71(12): 4817-4824, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36935587

RESUMO

The goal of this study was to expand the applications of bamboo leaf flavonoids (BLFs) by improving their lipophilicity through enzymatic acylation with vinyl cinnamate. Characterization of the acylated BLFs using Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, high-resolution electrospray ionization mass spectrometry, electrospray ionization with tandem mass spectrometry, and 1H nuclear magnetic resonance spectroscopy indicated that acylation occurred at the C6-OH position of glucoside moieties. The highest degree of acylation (18.61%) was obtained by reacting BLFs with vinyl cinnamate (1:5, w/w) at 60 °C for 48 h. Acylation significantly improved the lipophilicity of BLFs and their capacity to inhibit lipid peroxidation, as evidenced by the reduced production of lipid hydroperoxides and malondialdehyde in rapeseed oil and rapeseed oil-in-water emulsions during storage at 37 °C for 15 days. The study findings provide important data that will enable the use of BLFs in lipid or lipophilic matrices, such as oil-based foods.


Assuntos
Antioxidantes , Flavonoides , Antioxidantes/química , Flavonoides/química , Óleo de Brassica napus , Acilação , Folhas de Planta/química
5.
Molecules ; 27(19)2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36234873

RESUMO

Phenolic compounds from the flower of Clitoria ternatea L. (PCFCTL) were extracted using a high-speed shearing extraction technique and purified by AB-8 macroporous resins, and the phytochemical composition of the purified phenolic compounds from the flower of Clitoria ternatea L. (PPCFCTL) was then analyzed. Subsequently, its bioactivities including antioxidant properties, enzyme inhibitory activities, and antiproliferative activities against several tumor cell lines were evaluated. Results indicated that the contents of total phenolics, flavonoids, flavonols, flavanols, and phenolic acids in PPCFCTL were increased by 3.29, 4.11, 2.74, 2.43, and 2.96-fold, respectively, compared with those before being purified by AB-8 macroporous resins. The results showed PPCFCTL have significant antioxidant ability (measured by reducing power, RP, and ferric reducing antioxidant power method, FRAP) and good DPPH, ABTS+, and superoxide anion radical scavenging activities. They can also significantly inhibit lipase, α-amylase, and α-glucosidase. In addition, morphological changes of HeLa, HepG2, and NCI-H460 tumor cells demonstrated the superior antitumor performance of PPCFCTL. However, the acetylcholinesterase inhibitory activity was relatively weak. These findings suggest that PPCFCTL have important potential as natural antioxidant, antilipidemic, anti-glycemic and antineoplastic agents in health-promoting foods.


Assuntos
Clitoria , Acetilcolinesterase , Antioxidantes/química , Clitoria/química , Flavonoides/análise , Flavonoides/farmacologia , Flavonóis/análise , Flores/química , Lipase/análise , Fenóis/análise , Fenóis/farmacologia , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Superóxidos/análise , alfa-Amilases , alfa-Glucosidases
6.
Molecules ; 27(8)2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35458651

RESUMO

Chenopodium quinoa Willd. is recognized to be an excellent nutrient with high nutritional content. However, few genotypes of quinoa were analyzed, so we found a knowledge gap in the comparison of quinoa seeds of different genotypes. This study aims to compare the physicochemical, antioxidant, and anticancer properties of seed oil from three C. quinoa genotypes. Seeds of three genotypes (white, red, and black) were extracted with hexane and compared in this study. The oil yields of these quinoa seeds were 5.68-6.19% which contained predominantly polyunsaturated fatty acids (82.78-85.52%). The total tocopherol content ranged from 117.29 to 156.67 mg/kg and mainly consisted of γ-tocopherol. Total phytosterols in the three oils ranged from 9.4 to 12.2 g/kg. Black quinoa seed oil had the highest phytosterols followed by red and white quinoas. The chemical profile of quinoa seed oils paralleled by their antioxidant and anticancer activities in vitro was positively correlated with the seed coat color. Black quinoa seed oil had the best antioxidant and anti-proliferation effect on HCT 116 cells by the induction of apoptosis in a dose-dependent manner, which may play more significant roles in the chemoprevention of cancer and other diseases related to oxidative stress as a source of functional foods.


Assuntos
Chenopodium quinoa , Fitosteróis , Antioxidantes/análise , Antioxidantes/farmacologia , Chenopodium quinoa/química , Genótipo , Fitosteróis/análise , Fitosteróis/farmacologia , Óleos de Plantas/química , Sementes/química
8.
J Magn Reson ; 301: 73-79, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30851668

RESUMO

Effective coil combination methods for human hyperpolarized 13C spectroscopy multi-channel data had been relatively unexplored. This study implemented and tested several coil combination methods, including (1) the sum-of-squares (SOS), (2) singular value decomposition (SVD), (3) Roemer method by using reference peak area as a sensitivity map (RefPeak), and (4) Roemer method by using ESPIRiT-derived sensitivity map (ESPIRiT). These methods were evaluated by numerical simulation, thermal phantom experiments, and human cancer patient studies. Overall, the SVD, RefPeak, and ESPIRiT methods demonstrated better accuracy and robustness than the SOS method. Extracting complex pyruvate signal provides an easy and excellent approximation of the coil sensitivity map while maintaining valuable phase information of the coil-combined data.


Assuntos
Imagem Molecular/métodos , Algoritmos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Isótopos de Carbono , Simulação por Computador , Campos Eletromagnéticos , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Neoplasias/diagnóstico por imagem , Imagens de Fantasmas , Ácido Pirúvico/química , Reprodutibilidade dos Testes , Razão Sinal-Ruído
9.
Magn Reson Med ; 81(2): 839-851, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30277268

RESUMO

PURPOSE: Acquisition timing and B1 calibration are two key factors that affect the quality and accuracy of hyperpolarized 13 C MRI. The goal of this project was to develop a new approach using regional bolus tracking to trigger Bloch-Siegert B1 mapping and real-time B1 calibration based on regional B1 measurements, followed by dynamic imaging of hyperpolarized 13 C metabolites in vivo. METHODS: The proposed approach was implemented on a system which allows real-time data processing and real-time control on the sequence. Real-time center frequency calibration upon the bolus arrival was also added. The feasibility of applying the proposed framework for in vivo hyperpolarized 13 C imaging was tested on healthy rats, tumor-bearing mice and a healthy volunteer on a clinical 3T scanner following hyperpolarized [1-13 C]pyruvate injection. Multichannel receive coils were used in the human study. RESULTS: Automatic acquisition timing based on either regional bolus peak or bolus arrival was achieved with the proposed framework. Reduced blurring artifacts in real-time reconstructed images were observed with real-time center frequency calibration. Real-time computed B1 scaling factors agreed with real-time acquired B1 maps. Flip angle correction using B1 maps results in a more consistent quantification of metabolic activity (i.e, pyruvate-to-lactate conversion, kPL ). Experiment recordings are provided to demonstrate the real-time actions during the experiment. CONCLUSIONS: The proposed method was successfully demonstrated on animals and a human volunteer, and is anticipated to improve the efficient use of the hyperpolarized signal as well as the accuracy and robustness of hyperpolarized 13 C imaging.


Assuntos
Isótopos de Carbono/química , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética , Adulto , Algoritmos , Animais , Mapeamento Encefálico , Calibragem , Modelos Animais de Doenças , Voluntários Saudáveis , Humanos , Masculino , Camundongos , Transplante de Neoplasias , Distribuição Normal , Reconhecimento Automatizado de Padrão , Neoplasias da Próstata/diagnóstico por imagem , Ácido Pirúvico , Ratos
10.
Magn Reson Med ; 81(3): 2001-2010, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30368893

RESUMO

PURPOSE: To develop a pulse sequence to dynamically measure the ADC of hyperpolarized substrates during their perfusion, metabolic conversion, and transport. METHODS: We proposed a slice-selective double spin echo sequence for dynamic hyperpolarized 13 C diffusion-weighted imaging. The proposed pulse sequence was optimized for a high field preclinical scanner through theoretical analysis and simulation. The performance of the method was compared to non-slice-selective double spin echo via in vivo studies. We also validated the sequence for dynamic ADC measurement in both phantom studies and transgenic mouse model of prostate cancer studies. RESULTS: The optimized pulse sequence outperforms the traditional sequence with smaller saturation effects on the magnetization of hyperpolarized compounds that allowed more dynamic imaging frames covering a longer imaging time window. In pre-clinical studies (N = 8), the dynamic hyperpolarized lactate ADC maps of 6 studies in the prostate tumors showed an increase measured ADC over time, which might be related to lactate efflux from the tumor cells. CONCLUSIONS: The proposed sequence was validated and shown to improve dynamic diffusion weighted imaging compared to the traditional double spin echo sequence, providing ADC maps of lactate through time.


Assuntos
Espectroscopia de Ressonância Magnética Nuclear de Carbono-13/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Animais , Simulação por Computador , Ácido Láctico/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Modelos Teóricos , Imagens de Fantasmas , Piruvatos/metabolismo
11.
Phys Med Biol ; 63(18): 185002, 2018 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-30106008

RESUMO

Respiratory motion causes misalignments between positron emission tomography (PET) and magnetic resonance (MR)-derived attenuation maps (µ-maps) in addition to artifacts on both PET and MR images in simultaneous PET/MRI for organs such as liver that can experience motion of several centimeters. To address this problem, we developed an efficient MR-based attenuation correction (MRAC) method to generate phase-matched µ-maps for quiescent period PET (PETQ) in abdominal PET/MRI. MRAC data was acquired with CIRcular Cartesian UnderSampling (CIRCUS) sampling during 100 s in free-breathing as an accelerated data acquisition strategy for phase-matched MRAC (MRACPM-CIRCUS). For comparison, MRAC data with raster (Default) k-space sampling was also acquired during 100 s in free-breathing (MRACPM-Default), and used to evaluate MRACPM-CIRCUS as well as un-matched MRAC (MRACUM) that was un-gated. We purposefully oversampled the MRACPM data to ensure we had enough information to capture all respiratory phases to make this comparison as robust as possible. The proposed MRACPM-CIRCUS was evaluated in 17 patients with 68Ga-DOTA-TOC PET/MRI exams, suspected of having neuroendocrine tumors or liver metastases. Effects of CIRCUS sampling for accelerating a data acquisition were evaluated by simulating the data acquisition time retrospectively in increments of 5 s. Effects of MRACPM-CIRCUS on PETQ were evaluated using uptake differences in the liver lesions (n = 35), compared to PETQ with MRACPM-Default and MRACUM. A Wilcoxon signed-rank test was performed to compare lesion uptakes between the MRAC methods. MRACPM-CIRCUS showed higher image quality compared to MRACPM-Default for the same acquisition times, demonstrating that a data acquisition time of 30 s was reasonable to achieve phase-matched µ-maps. Lesion update differences between MRACPM-CIRCUS (30 s) versus MRACPM-Default (reference, 100 s) were 0.1% ± 1.4% (range of -2.7% to 3.2%) and not significant (P > .05); while, the differences between MRACUM versus MRACPM-Default were 0.6% ± 11.4% with a large variation (range of -37% to 20%) and significant (P < .05). In conclusion, we demonstrated that a data acquisition of 30 s achieved phase-matched µ-maps when using specialized CIRCUS data sampling and phase-matched µ-maps improved PETQ quantification significantly.


Assuntos
Abdome/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Respiração
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA