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1.
Foods ; 13(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38998550

RESUMO

Rosa roxburghii Tratt pomace (RRTP), an underutilized byproduct, is rich in polyphenol compounds. This study aimed to further explore the purification, characterization, anti-inflammatory activities, and underlying molecular mechanisms of free polyphenols (RRTP-FP) and bound polyphenols (RRTP-BP) from RRTP. The results indicated that AB-8 macroporous resin emerged as the preferred choice for subsequent separation and purification. The purities of purified RRTP-FP (P-RRTP-FP) and purified RRTP-BP (P-RRTP-BP) increased by 103.34% and 66.01%, respectively. Quantitative analysis identified epigallocatechin, epicatechin, and ellagic acid as the main phenolic compounds in P-RRTP-FP. In P-RRTP-BP, the primary phenolic compounds were ellagic acid, epicatechin, and gallic acid. In vitro antioxidant assays demonstrated the superior DPPH and ABTS radical scavenging activities of P-RRTP-FP and P-RRTP-BP compared to vitamin C. Treatment with P-RRTP-FP and P-RRTP-BP reduced nitric oxide (NO) and reactive oxygen species (ROS) production, mitigated the decline in cellular membrane potential, and significantly downregulated the mRNA expression of pro-inflammatory cytokines and inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Additionally, P-RRTP-FP and P-RRTP-BP inhibited the phosphorylation of pertinent proteins in the nuclear factor kappa-B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. This finding suggests potential utility of RRTP-derived polyphenols as anti-inflammatory agents for managing severe inflammatory conditions.

2.
J Agric Food Chem ; 71(46): 17554-17569, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37955247

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease characterized by lipid metabolic disorder primarily due to sedentary lifestyles and excessive food consumption. However, there are currently no approved and effective drugs available to treat NAFLD. In recent years, research has shown that dietary bioactive compounds, such as polysaccharides, polyphenols, flavones, and alkaloids, have the potential to improve NAFLD by regulating autophagy. However, there is no up-to-date review of research progress in this field. This review aims to systematically summarize and discuss the regulatory effects and molecular mechanisms of dietary bioactive compounds on NAFLD through the modulation of autophagy. The existing research has demonstrated that some dietary bioactive compounds can effectively improve various aspects of NAFLD progression, such as lipid metabolism, insulin resistance (IR), endoplasmic reticulum (ER) stress, oxidative stress, mitochondrial homeostasis, and inflammation. Molecular mechanism studies have revealed that they exert their beneficial effects on NAFLD through autophagy-mediated signaling pathways, predominantly involving transcription factor EB (TFEB), mammalian target of rapamycin (mTOR), adenosine monophosphate-activated protein kinase (AMPK), peroxisome proliferator-activated receptors (PPARs), SIRT, and PTEN-induced kinase 1 (PINK1)/parkin. Furthermore, the challenges and prospects of current research in this field are highlighted. Overall, this review provides valuable insights into the potential treatment of NAFLD using dietary bioactive compounds that can modulate autophagy.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Metabolismo dos Lipídeos , Estresse Oxidativo , Polifenóis/metabolismo , Autofagia , Fígado/metabolismo
3.
Int J Biol Macromol ; 251: 126408, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37598818

RESUMO

The flower of Hylocereus undatus (Haw.) Britton et Rose is widely recognized as a kind of medicine-food homologous resource due to its high nutritional value. However, there is a lack of in-depth studies on the purification, structure, antioxidative and immunoregulatory activities of polysaccharides from H. undatus flowers (FHRP). The objective of this study was to investigate the primary structure, antioxidative and immunoregulatory activities of the polysaccharides extracted from Hylocereus undatus flower using water extraction and chromatogram purification. Three polysaccharide fractions named FHRP-1, FHRP-2 and FHRP-3 were obtained. The results showed that FHRP-1, FHRP-2 and FHRP-3 (200-800 µg/mL) treatment for 24 h significantly increased the activities of superoxide dismutase (SOD) and catalase (CAT), and reduced the malondialdehyde (MDA) production in RAW 246.7 cells under H2O2-induced oxidative stress. Additionally, all three fractions exhibited immunoregulatory activities by enhancing the pinocytosis of RAW 264.7 cells and promoting the production of nitric oxide (NO), interleukin 6 (IL-6), and tumor necrosis factor α (TNF-α). Among three polysaccharide fractions, FHRP-3 exhibited the most promising antioxidative and immunoregulatory properties, which was attributed to its higher content of uronic acid, moderate molecular weight, and triple-helix conformation. These findings provide preliminary insights into the primary structural information and biological activities of FHRP.

4.
Crit Rev Food Sci Nutr ; : 1-21, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37114929

RESUMO

In recent years, RG-I pectin isolated by low-temperature alkaline extraction methods has attracted the attention of a large number of researchers due to its huge health benefits. However, studies on other applications of RG-I pectin are still lacking. In this study, we summarized the sources (e.g. potato pulp, sugar beet pulp, okra, apple pomace, citrus peel, pumpkin, grapefruit, ginseng, etc.), extraction methods, fine structure and applications of RG-I pectin in physiological activities (e.g. anti-cancer, anti-inflammatory, anti-obesity, anti-oxidation, immune regulation, prebiotics, etc.), emulsions, gels, etc. These neutral sugar side chains not only endow RG-I pectin with various physiological activities but the entanglement and cross-linking of these side chains also endow RG-I pectin with excellent emulsifying and gelling properties. We believe that this review can not only provide a comprehensive reading for new workers interested in RG-I pectin, but also provide a valuable reference for future research directions of RG-I pectin.

5.
Carbohydr Polym ; 302: 120386, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36604064

RESUMO

Starch cryogel is a potential material for oil absorption. This study provided a facile and convenient polyelectrolyte-based preparation strategy of starch cryogel, in which the structural properties of the cryogel were regulated by amylose content and pre-freezing without long-time retrogradation. Sodium laurate was used as a guest model to form starch-fatty acid salt complex (polyelectrolyte). The amount of amylose content and sodium laurate added led more polyelectrolytes, significantly increased V-type crystallinity from 3.72 % to 22.40 % and complexing index from 4.32 % to 28.48 %. As the uniform pore structure improved the oil absorption ability of starch cryogel, the starch cryogel prepared by waxy maize starch followed by quick pre-freezing showed the highest specific surface area (9.87 m2/g) and oil absorption capacity (32.94 g/g). Our findings suggest that polyelectrolyte properties have great potential in the preparation of starch-based cryogels, which could be applied in the design of novel starch-based porous materials.


Assuntos
Amilose , Amido , Amido/química , Amilose/química , Criogéis , Polieletrólitos , Congelamento , Amilopectina/química
6.
Food Funct ; 13(24): 12561-12571, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36453451

RESUMO

Rosa roxburghii Tratt fruit (RRF), known commonly as Cili in China, is a highly valued fruit that contains abundant functional and nutritional constituents with a variety of health-promoting benefits. Polysaccharides (RRFPs) are regarded as one of the crucial biological compounds in RRF. Existing literature has shown that RRFPs possess various remarkable biological activities, such as antioxidant, hypoglycemic, antitumor, anti-inflammatory, and gut microbiota modulation capabilities. In recent years, isolation and purification methods, structural characteristics, and biological activities of RRFPs have been drawing increasing attention. However, there is no up-to-date review of research progress on this front. In this review, recent advances in RRFPs, including their isolation, purification, structural characterization, biological activity, and the structure-activity relationship are summarized and discussed. In addition, this review highlights the challenges and prospects of RRFPs. Overall, this review provides useful research underpinnings and updated information for the further development and utilization of RRFPs in the fields of health, food, and medicine.


Assuntos
Rosa , Rosa/química , Frutas/química , Polissacarídeos/química , Antioxidantes/química , Extratos Vegetais/química
7.
Carbohydr Polym ; 297: 120015, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36184138

RESUMO

Starch-based carriers have a great potential in functional oil encapsulation because of their mild preparation conditions, but the oil loading capacity and underlying anti-oxidation mechanism remain unclear. Here V-type starches were applied to fabricate flaxseed oil powder. Particle size analysis and scanning electron microscopy showed a loose aggregation microstructure of normal maize starch (NMS) prepared using the anti-solvent (AS) precipitation method, with an average size of 24.9 µm. Differential scanning calorimetry displayed a good thermo-oxidation resistance of NMS-derived V-type starch prepared via AS precipitation. Principal component analysis revealed that the oil loading capacity, related closely to V-type crystallinity and D50, has a significant positive correlation with the onset oxidation temperature and a negative correlation with the peroxide, thiobarbituric acid, and ρ-anisidine values. Our original study reveals the effects of V-type crystallinity and aggregation microstructure on the oil loading capacity and anti-oxidation, providing theoretical guidance for developing novel, starch-based carriers.


Assuntos
Óleo de Semente do Linho , Amido , Óleo de Semente do Linho/química , Tamanho da Partícula , Peróxidos , Pós , Amido/química
8.
Curr Res Food Sci ; 5: 1581-1589, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36161228

RESUMO

Rosa roxburghii Tratt fruit is a highly valued fruit that contains abundant functional and nutritional constituents. In this study, a novel polysaccharide, named RTFP-1, was isolated and purified from R. roxburghii Tratt fruit. Structural characterization indicated that RTFP-1 was a homogeneous heteropolysaccharide with the molecular weight (Mw) of 128.7 kDa and consisted of arabinose, galactose, glucose, mannose, xylose, and fucose with molar ratio percentages of 34.84, 40.59, 12.11, 5.06, 3.39, and 4.01%, respectively. A CCK-8 assay indicated that RTFP-1 inhibited the cell growth of HepG2 cells in a dose-dependent manner. Morphological analysis and flow cytometry experiment showed that RTFP-1 promoted the apoptosis of HepG2 cells and increased reactive oxygen species (ROS) level. The underlying molecular mechanisms indicated that RTFP-1 activated the apoptosis of HepG2 cells through ROS-mediated MAPK, STAT, and p53 apoptotic pathways. These results suggest that RTFP-1 might be a potential chemopreventive and antitumor agent.

9.
Food Funct ; 13(17): 8880-8891, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35924964

RESUMO

The aim of this study was to elucidate the liberation and phytochemical profile of bound polyphenols present in dietary fiber (RPDF) isolated from Rosa roxburghii fruit pomace during in vitro-simulated digestion and colonic fermentation. The variation in the biological activity and prebiotic potential of the released polyphenols from RPDF was investigated. The results showed that the bound polyphenols were released from RPDF at a higher ratio during colonic fermentation than gastrointestinal digestion. The released polyphenols showed antioxidant activity and α-glucosidase inhibitory activity. The in vitro colonic fermentation assay showed that compared with dephenolized RPDF (DP-RPDF), RPDF exhibited a significantly stronger prebiotic effect by lowering the Firmicutes to Bacteroidetes (F/B) ratio at the phylum level, increasing the relative abundances of beneficial bacteria at the genus level, and improving the production of short chain fatty acids (SCFAs). These findings indicate that the bound polyphenols may act as important functional food ingredients that can contribute to the biological properties of RPDF. In addition, this study provides new insights into the high-value utilization of Rosa roxburghii fruit pomace, which will reduce the wastage of resources and greatly contribute to environmental protection.


Assuntos
Polifenóis , Rosa , Fibras na Dieta/análise , Digestão , Fermentação , Frutas/química , Compostos Fitoquímicos/análise , Polifenóis/química , Prebióticos/análise
10.
Front Neurol ; 13: 890126, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35651348

RESUMO

Objective: In moyamoya disease (MMD) with direct or combined revascularization, the initially hemodynamic recipient features are likely one of the main causes of acute hemodynamic disruption. Previous studies have explored the relationship between recipient diameter or flow velocity and postoperative complications, but there are still no optimal selection criteria with multiple potential recipient vessels. Cerebral edema is one of the most common radiological manifestations in the acute postoperative period. This study assessed the hemodynamic characteristics of cortex vessels related to postoperative cerebral edema. Methods: All patients who had undergone direct or combined revascularization with preoperative digital subtraction angiography (DSA) between 2019 and 2021 were eligible for inclusion in this study. The application of DSA was performed and regular radiological examinations were employed after surgery. DSA was analyzed with the hemodynamic features within chosen recipient vessels. Cerebral edema was identified as a low-density image on CT or high signaling in the MRI T2 phase. The recipient hemodynamic characteristics and demographic presentation, as well as clinical data, were retrospectively analyzed in this study. Results: A total of 103 patients underwent direct or combined revascularization with preoperative DSA. The mean age of this enrolled cohort was 44.31 ± 10.386 years, in which bilaterally involved MMD accounted for the main part. The preliminary correlation analysis found preoperative disease period (p = 0.078), recipients observed in angiography (p = 0.002), and surgery on the left (p = 0.097) may be associated with cerebral edema. The following regression analysis confirmed low occurrence of cerebral edema was accompanied by recipients observed in angiography (p = 0.003). After subdividing by flow direction and hemodynamic sources, the incidence rate of anterograde direction, anterior sources, and posterior sources were significantly lower than undetected recipients. Conclusions: Cerebral edema is a common radiological manifestation in MMDs after surgery. In this study, the observation in angiography reliably identifies a variety of physiological or pathological recipient detection, flow direction, and hemodynamic sources in patients with MMD after revascularization, which indicates the selection strategy of potential recipients and highlights the importance of recipient observability in DSA. Meanwhile, vascular conditions determined by recipient hemodynamics meditate the occurrence of postoperative cerebral edema.

11.
Carbohydr Polym ; 291: 119556, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35698332

RESUMO

In this study, the effects of n-decanoic acid (n-CA) or coconut oil (CCN) on the release of ethylene from V-type starch (VS) were investigated. Results of differential scanning calorimetry showed that adding n-CA or CCN into VS generated a starch-lipid complex. Results of scanning electron microscopy and confocal laser scanning microscopy indicated that VS granules aggregated but oil films appeared on the surface of the VS aggregates when oil was added. The addition of n-CA or CCN effectively delayed the release of ethylene in VS, and the deceleration effect gradually became obvious with the increase in oil addition. These results suggest that the formation of starch-lipid complexes, the aggregation of starch granules, and the presence of oil films play important roles in slowing down the release of ethylene.


Assuntos
Etilenos , Amido , Varredura Diferencial de Calorimetria , Etilenos/química , Lipídeos/química , Microscopia Eletrônica de Varredura , Amido/química
12.
Carbohydr Polym ; 292: 119715, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35725189

RESUMO

Hydrophobic-modified starch complexes have the potential to form Pickering emulsions and improve the oxidative stability of flaxseed oil. Here, V-type starch-lauric acid complexes (SLACs) were fabricated via solid encapsulation within 0.5-12 h and applied in flaxseed oil Pickering emulsions. Complexing index, X-ray diffraction and differential scanning calorimetry analyses confirmed that the degree of complexation increased with the reaction time. Pickering emulsion gels stabilised by SLACs generated with reaction times of 6 h and 12 h exhibited good storage stability and high yield stress, G' values and apparent viscosity. Confocal laser scanning microscopy and cryo-scanning electron microscopy revealed a gelation mechanism involving increased interface roughness and enhanced droplet-droplet interaction. In comparison to pure flaxseed oil, higher thermo-oxidative resistance was observed at 130 °C, with a markedly longer oxidation induction for emulsions and emulsion gels stabilised by SLACs. Our findings could assist in the design of hydrophobic-modified starch and provide a new paradigm for delaying oil oxidation.


Assuntos
Óleo de Semente do Linho , Amido , Emulsões/química , Géis , Ácidos Láuricos , Óleo de Semente do Linho/química , Estresse Oxidativo , Tamanho da Partícula , Amido/química , Água/química
13.
Med Phys ; 49(8): 5464-5475, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35593052

RESUMO

PURPOSE: Experimental measurements of two-dimensional (2D) dose rate distributions in proton pencil beam scanning (PBS) FLASH radiation therapy (RT) are currently lacking. In this study, we characterize a newly designed 2D strip-segmented ionization chamber array (SICA) with high spatial and temporal resolution and demonstrate its applications in a modern proton PBS delivery system at both conventional and ultrahigh dose rates. METHODS: A dedicated research beamline of the Varian ProBeam system was employed to deliver a 250-MeV proton PBS beam with nozzle currents up to 215 nA. In the research and clinical beamlines, the spatial, temporal, and dosimetric performances of the SICA were characterized and compared with measurements using parallel-plate ion chambers (IBA PPC05 and PTW Advanced Markus chamber), a 2D scintillator camera (IBA Lynx), Gafchromic films (EBT-XD), and a Faraday cup. A novel reconstruction approach was proposed to enable the measurement of 2D dose and dose rate distributions using such a strip-type detector. RESULTS: The SICA demonstrated a position accuracy of 0.12 ± 0.02 mm at a 20-kHz sampling rate (50 µs per event) and a linearity of R2  > 0.99 for both dose and dose rate with nozzle beam currents ranging from 1 to 215 nA. The 2D dose comparison to the film measurement resulted in a gamma passing rate of 99.8% (2 mm/2%). A measurement-based proton PBS 2D FLASH dose rate distribution was compared to simulation results and showed a gamma passing rate of 97.3% (2 mm/2%). CONCLUSIONS: The newly designed SICA demonstrated excellent spatial, temporal, and dosimetric performances and is well suited for commissioning, quality assurance, and a wide range of clinical applications in proton PBS clinical and FLASH-RT.


Assuntos
Terapia com Prótons , Prótons , Imagens de Fantasmas , Terapia com Prótons/métodos , Radiometria/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Síncrotrons
14.
J Int Med Res ; 50(5): 3000605221096379, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35538703

RESUMO

A giant cervical goiter, defined as a thyroid mass larger than 8 cm in diameter, is usually a nodular or adenomatous goiter. A giant cervical goiter can also be caused by hyperthyroidism (i.e., Hashimoto's thyroiditis). The surgical indications for patients with Hashimoto's disease include suspected malignant tumors, persistent symptoms related to the disease, or persistent enlargement of the goiter. We herein describe a woman who developed symptoms of compression from a thyroid tumor, the volume of which was almost the largest reported in the relevant literature to date. The bilateral lobes of the giant thyroid tumor were removed by total en bloc excision. We protected the bilateral recurrent laryngeal nerve and preserved the bilateral upper and lower parathyroid glands in situ. The excised left lobe tumor was 16 × 9 × 5.5 cm, whereas the right lobe tumor was 12 × 8 × 4 cm. The pathological diagnosis was Hashimoto's thyroiditis. Although surgical excision is difficult, it is still the main treatment modality for giant goiters in patients with Hashimoto's thyroiditis and can help to reduce the occurrence of complications.


Assuntos
Bócio , Doença de Hashimoto , Hipertireoidismo , Doenças da Glândula Tireoide , Neoplasias da Glândula Tireoide , Feminino , Bócio/complicações , Bócio/cirurgia , Doença de Hashimoto/complicações , Doença de Hashimoto/cirurgia , Humanos , Hipertireoidismo/complicações , Neoplasias da Glândula Tireoide/complicações
15.
Food Chem ; 387: 132868, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35381416

RESUMO

Soybean peptides serve as functional foods with impressive health benefits. The structure characteristics of peptides are highly related to the health benefits. The structure-activity relationship and mechanism underlined are important scientific questions in this field. To answer these questions, soybean peptides were produced by combinatory enzymatic hydrolysis in this work. Fifty-two peptide sequences were identified by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). The anti-inflammatory activities of these peptides were investigated by using a lipopolysaccharide (LPS)-induced inflammation cell model. Soybean peptides could significantly promote cell proliferation. Additionally, soybean peptides could alleviate LPS-induced inflammation by reducing the production and expression of nitric oxide (NO), tumor necrosis factor alpha (TNF-α), interleukin-1ß (IL-1ß) and interleukin-6 (IL-6). Moreover, soybean peptides could promote the mRNA expression of proteins related to inflammation inhibition (IL-10) and tight junction modulation. The structure-activity relationship was addressed. The results documented the potential of soybean peptides as functional foods.


Assuntos
Glycine max , Lipopolissacarídeos , Inflamação/tratamento farmacológico , Inflamação/genética , Interleucina-6/genética , Interleucina-6/metabolismo , Peptídeos/química , Peptídeos/genética , Peptídeos/farmacologia , Glycine max/química , Espectrometria de Massas em Tandem , Fator de Necrose Tumoral alfa/metabolismo
16.
Int J Biol Macromol ; 208: 196-207, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35307461

RESUMO

Sargassum pallidum polysaccharide nanoparticle (nSPP-30) was prepared via antisolvent precipitation method and the preparation conditions were optimized. The effects of nanocrystallization on the structure and biological activities of S. pallidum polysaccharide were investigated. Under the optimal preparation condition, the average particle size, polydispersity index (PDI), and ξ-potential of nSPP-30 were 229.63 nm, 0.407, and -28.43 mV, respectively. Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) analyses indicated that nanocrystallization did not change primary and crystal structures of S. pallidum polysaccharide. However, nanocrystallization could improve the swelling, thermodynamic, and antioxidant properties of S. pallidum polysaccharide. In addition, the thymol adsorption capacity of nSPP-30 was enhanced as compared to the corresponding polysaccharide. These results suggest that nSPP-30 can be developed as a potential antioxidant or natural nano-carrier to encapsulate thymol for practical applications.


Assuntos
Nanopartículas , Sargassum , Adsorção , Antioxidantes/química , Antioxidantes/farmacologia , Carboidratos da Dieta , Globo Pálido , Nanopartículas/química , Tamanho da Partícula , Polissacarídeos/química , Polissacarídeos/farmacologia , Sargassum/química , Espectroscopia de Infravermelho com Transformada de Fourier , Timol
17.
Food Chem ; 377: 131922, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-34979396

RESUMO

Rosa roxburghii Tratt pomace (RRTP) has increasingly attracted attention due to its various nutritional ingredients and health benefits. In this study, the free phenolic fraction (RRTP-FPF) and bound phenolic fraction (RRTP-BPF) were extracted from RRTP by solvent extraction method and alkaline hydrolysis method, respectively. The composition of polyphenols in RRTP-FPF and RRTP-BPF were identified by ultra-high performance liquid chromatography equipped with an electrospray ionization and quadrupole time-of-flight mass spectrometry (UHPLC-ESI-QTOF-MS/MS). In vitro antioxidant assays indicated that RRTP-FPF and RRTP-BPF could scavenge radicals in a dose-dependent manner, and RRTP-BPF exhibited better scavenging activity than RRTP-FPF. In addition, RRTP-FPF and RRTP-BPF (20 âˆ¼ 100 µg/mL) treatment for 24 h could significantly increase the survival rate and decrease reactive oxygen species (ROS) level of paraquat-exposed nematodes through improving the activities of superoxide dismutase (SOD) and catalase (CAT). These results suggest that RRTP could be as a good and cheap source of natural antioxidants.


Assuntos
Antioxidantes , Polifenóis , Rosa , Animais , Antioxidantes/farmacologia , Cromatografia Líquida de Alta Pressão , Nematoides/efeitos dos fármacos , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Rosa/química , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
18.
Carbohydr Polym ; 277: 118814, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34893231

RESUMO

The objective of this research was to investigate the effects of preparation method on the characteristics and ethylene loading capacity of V-type linear dextrin (LD). LD with different degrees of polymerisation were obtained from debranched starch by gradient ethanol precipitation. X-ray diffraction (XRD) patterns of samples obtained by precipitation and anti-solvent precipitation presented A + V-type crystalline structure. However, the percentage of V-type structure of samples obtained by anti-solvent precipitation was significantly higher than for samples prepared by precipitation, which was further confirmed by nuclear magnetic resonance spectroscopy (NMR), and molecular dynamics simulation supported the XRD and NMR results. The ethylene encapsulation capabilities of samples fabricated by different methods were in range of 1.15-4.68 cm3/g. Ethylene release from V-type LD was a physical process at different storage temperatures, and the higher percentage of V-type structure, the slower release rate. Thus, a higher V-type structure content was beneficial for encapsulation of gaseous molecules.

19.
Food Funct ; 11(12): 10886-10895, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33241822

RESUMO

Glycosylation has a great effect on the antioxidant ability of proteins, which is due to the structural conformational change of peptides in the protein. In this study, a chitosan oligosaccharide (COS) was selected as the saccharide for glycation with lactoferrin (LF) by a wet-heat method, and a new stripe at a higher molecular zone in the gel of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and a change in the bond revealed by Fourier transform infrared (FT-IR) and fluorescence spectroscopy analyses were used to confirm that the chitosan oligosaccharide was successfully covalently bound to lactoferrin. The ABTS and oxygen radical absorbance capacity (ORAC) assays indicated that lactoferrin exhibited a stronger antioxidant activity after glycation with the chitosan oligosaccharide. High-resolution mass spectroscopy further illuminated the relationship of enhanced antioxidant capacity and structural conformational change of peptides in lactoferrin at a molecular level.


Assuntos
Antioxidantes/química , Quitosana/química , Lactoferrina/química , Oligossacarídeos/química , Antioxidantes/metabolismo , Quitosana/metabolismo , Eletroforese em Gel de Poliacrilamida , Glicosilação , Lactoferrina/metabolismo , Espectrometria de Massas/métodos , Oligossacarídeos/metabolismo , Capacidade de Absorbância de Radicais de Oxigênio , Peptídeos , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier
20.
ACS Appl Mater Interfaces ; 12(30): 34095-34104, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32627528

RESUMO

Two metal-organic framework (MOF) materials, that is, α-cyclodextrin (α-CD)-MOF-Na and α-CD-MOF-K, were successfully synthesized and exhibited excellent adsorption capacity and storage stability for ethylene gas. The ethylene encapsulation capacity of α-CD-MOF-Na and α-CD-MOF-K reached 47.4 and 52.9% (w/w), respectively, which was significantly higher than those of other materials reported such as α-CD and V-type starch. The release characteristics of ethylene inclusion complexes (ICs) were determined under different temperatures and relative humidity conditions. The ethylene gas could be stably encapsulated in α-CD-MOF-ethylene ICs at 25 °C for up to 30 days. The crystal structure of α-CD-MOFs was determined to explain their high capacity and stability for ethylene storage. Molecular simulation was used to model the location of ethylene molecules in α-CD-MOFs. Alpha-CD-MOF-Na and α-CD-MOF-K showed "8"-shaped and spindle-shaped cavity, respectively, which effectively adsorbed and stored the ethylene gas. Accelerated ripening experiments showed that 5 mg of α-CD-MOF ICs could ripen bananas within 4 days, with an effect similar to that of free ethylene gas. We suggest that α-CD-MOF materials are an excellent material for ethylene storage with potential application in industrial and agricultural areas.

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