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1.
Ying Yong Sheng Tai Xue Bao ; 34(9): 2481-2488, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37899115

RESUMO

The evaluation and optimization of landscape ecological pattern has important implications for the accurate improvement of forest quality and high-quality urban development in the Pearl River Delta urban agglomeration. Based on the "one map" data and digital elevation model data of forest resource management in 2021, we evaluated and optimized landscape ecological pattern of the Pearl River Delta urban agglomeration by morphological spatial pattern analysis and minimum cumulative resistance model. The results showed that there were 435861 patches in the Pearl River Delta urban agglomeration that could be used as ecological source area, covering an area of 7346.60 km2 and accounting for 13.4% of the Pearl River Delta area. Thirty patches were selected as the ecological source area of the study area by using the area and patch importance index, covering an area of 2792.59 km2 and accounting for 5.1% of the Pearl River Delta area. The overall natural environment of the Pearl River Delta urban agglomeration was excellent. The ecological resistance level was small. The peripheral ecological resistance was low. The core ecological resistance was high. There was still a large room for adjustment of stand types and landscape patterns, which should be optimized by adjusting the composition and spatial distribution of tree species. The ecological network of the Pearl River Delta urban agglomeration was optimized with 30 ecological sources, 103 key ecological corridors, and 95 ecological nodes. The improvement rates of the optimized probability of connectivity index and integral index of connectivity index were 297.5% and 695.1%, respectively. The optimization results could effectively connect the ecological sources and spread the ecological service functions of ecological sources.


Assuntos
Conservação dos Recursos Naturais , Rios , Florestas , Análise Espacial , China , Ecossistema , Cidades
2.
Huan Jing Ke Xue ; 44(9): 5017-5024, 2023 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-37699819

RESUMO

Antibiotic contamination in drinking water has attracted widespread attention. The pollution condition of six macrolide antibiotics (erythromycin-H2[KG-*2/5]O, clarithromycin, oleandomycin, roxithromycin, leucomycin, and tylosin) in two drinking water treatment plants was monitored, and the reaction mechanism of tylosin, a typical macrolide antibiotic, during chlorination disinfection treatment was investigated. The results showed that the six macrolide antibiotics can be widely detected in the drinking water treatment processes; however, their concentrations were generally very low. The concentrations of macrolide antibiotics in the influents and effluents ranged from 0.18 ng·L-1 to 3.97 ng·L-1 and 0.02 ng·L-1 to 1.91 ng·L-1, respectively. The removal rates of the six macrolides in the drinking water treatment were different, ranging from 18% (oleandomycin) to 100% (erythromycin- H2[KG-*2/5]O). The degradation of the six macrolides during chlorination was slow and greatly affected by water quality parameters. The chlorination degradation of tylosin followed the second-order reaction kinetic mode, with the kinetic rate constant of 0.77 L·(mol·s)-1 at pH 7.0. Nine chlorination degradation products of tylosin were detected, and the reaction pathways primarily included tertiary amine hydroxylation, aromatic oxidation, and epoxy addition.


Assuntos
Água Potável , Tilosina , Halogenação , Antibacterianos , Macrolídeos , Eritromicina , Oleandomicina
3.
Food Funct ; 14(16): 7574-7585, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37526948

RESUMO

In this study, the effect of sn-2 palmitic triacylglycerols (sn-2 palmitic TAGs) and the ratio between the two major sn-2 palmitic TAGs (OPL to OPO ratio) in a human milk fat substitute (HMFS) on growth, fatty acid and calcium absorptions, and lipid and bile acid metabolic alterations was investigated in Sprague-Dawley rats. After 4 weeks of high-fat feeding, rats fed with the HMFS containing a sn-2 palmitic acid content of 57.87% and an OPL to OPO ratio of 1.4 showed the lowest TAG accumulation in their livers and hypertrophy of perirenal adipocytes, compared to the groups fed with fats containing a lower sn-2 palmitic acid content or a lower OPL to OPO ratio. Meanwhile, synergistically improved absorption of fatty acids and calcium and increased levels of total bile acids (BAs), especially for the tauro-conjugated BAs (TCDCA, TUDCA, TαMCA, TßMCA, TDCA and TωMCA), were observed in rats by both increasing the sn-2 palmitic acid content and the OPL to OPO ratio in HMFS. In addition, the levels of total BAs and tauro-conjugated BAs were negatively correlated with serum TAG, TC, and LDL-c levels and positively correlated with HDL-c levels according to Spearman's correlation analysis (P < 0.05). Collectively, these findings present new nutritional evidence for the potential effects of the TAG structure and composition of a human milk fat substitute on the growth and lipid and bile acid metabolism of the host in infancy.


Assuntos
Substitutos da Gordura , Ácidos Graxos , Humanos , Ratos , Animais , Ácidos Graxos/metabolismo , Triglicerídeos , Leite Humano/química , Ratos Sprague-Dawley , Cálcio/metabolismo , Metabolismo dos Lipídeos , Ácido Palmítico/análise , Cálcio da Dieta , Ácidos e Sais Biliares/análise
4.
J Agric Food Chem ; 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37021496

RESUMO

Honeysuckle (Lonicerae japonicae) has been used in functional tea products. The chemical compositions of the water and ethanol extracts of honeysuckle were examined in the present study, along with their potential in inhibiting SARS-CoV-2 spike protein binding to ACE2, suppressing ACE2 activity, and scavenging reactive free radicals. Thirty-six compounds were tentatively identified from the honeysuckle extracts using HPLC-MS/MS, with ten reported for the first time in honeysuckle. Both honeysuckle extracts inhibited the binding of SARS-CoV-2 spike protein to ACE2, as well as ACE2 activity. The ethanol extract exhibited a 100% inhibition on binding of the SARS-CoV-2 spike protein to ACE2 at 100 mg botanical equivalent/mL, whereas the water extract had a 65% binding inhibition at the same concentration. Furthermore, the water extract exhibited 90% ACE2 activity inhibition, which was stronger than that of the ethanol extract (62% inhibition) at the same botanical weight concentration. In addition, higher total phenolic contents and greater scavenging activities against hydroxyl (HO•), DPPH•, and ABTS•+ radicals were observed in the water extract than the ethanol extract counterpart on a dry botanical weight concentration basis. These findings suggest honeysuckle has the potential to reduce the risk of SARS-CoV-2 infection and the development of severe COVID-19 symptoms.

5.
J Agric Food Chem ; 71(12): 4890-4900, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36940448

RESUMO

Cinnamon (Cinnamomum verum J. Presl) bark and its extracts are popular ingredients added to food and supplement products. It has various health effects, including potentially reducing the risk of coronavirus disease-2019 (COVID-19). In our study, the bioactives in cinnamon water and ethanol extracts were chemically identified, and their potential in suppressing SARS-CoV-2 spike protein-angiotensin-converting enzyme 2 (ACE2) binding, reducing ACE2 availability, and scavenging free radicals was investigated. Twenty-seven and twenty-three compounds were tentatively identified in cinnamon water and ethanol extracts, respectively. Seven compounds, including saccharumoside C, two emodin-glucuronide isomers, two physcion-glucuronide isomers, and two type-A proanthocyanidin hexamers, were first reported in cinnamon. Cinnamon water and ethanol extracts suppressed the binding of SARS-CoV-2 spike protein to ACE2 and inhibited ACE2 activity in a dose-dependent manner. Cinnamon ethanol extract had total phenolic content of 36.67 mg gallic acid equivalents (GAE)/g and free radical scavenging activities against HO• and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS•+) of 1688.85 and 882.88 µmol Trolox equivalents (TE)/g, which were significantly higher than those of the water extract at 24.12 mg GAE/g and 583.12 and 210.36 µmol TE/g. The free radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) of cinnamon ethanol extract was lower than that of the water extract. The present study provides new evidence that cinnamon reduces the risk of SARS-CoV-2 infection and COVID-19 development.


Assuntos
COVID-19 , Glicoproteína da Espícula de Coronavírus , Humanos , Cinnamomum zeylanicum , Enzima de Conversão de Angiotensina 2 , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Glucuronídeos , SARS-CoV-2 , Radicais Livres , Ácido Gálico , Etanol/química , Água/química , Ligação Proteica
6.
J Agric Food Chem ; 70(45): 14403-14413, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36318658

RESUMO

COVID-19 is initiated by binding the SARS-CoV-2 spike protein to angiotensin-converting enzyme 2 (ACE2) on host cells. Food factors capable of suppressing the binding between the SARS-CoV-2 spike protein and ACE2 or reducing the ACE2 availability through ACE2 inhibitions may potentially reduce the risk of SARS-CoV-2 infection and COVID-19. In this study, the chemical compositions of clove water and ethanol extracts were investigated, along with their potentials in suppressing SARS-CoV-2 spike protein-ACE2 binding, reducing ACE2 availability, and scavenging free radicals. Thirty-four compounds were tentatively identified in the clove water and ethanol extracts, with six reported in clove for the first time. Clove water and ethanol extracts dose-dependently suppressed SARS-CoV-2 spike protein binding to ACE2 and inhibited ACE2 activity. The water extract had stronger inhibitory effects than the ethanol extract on a dry weight basis. The clove water extract also had more potent free radical scavenging activities against DPPH• and ABTS•+ (536.9 and 3525.06 µmol TE/g, respectively) than the ethanol extract (58.44 and 2298.01 µmol TE/g, respectively). In contrast, the ethanol extract had greater total phenolic content (TPC) and relative HO• scavenging capacity (HOSC) values (180.03 mg GAE/g and 2181.08 µmol TE/g, respectively) than the water extract (120.12 mg GAE/g and 1483.02 µmol TE/g, respectively). The present study demonstrated the potential of clove in reducing the risk of SARS-CoV-2 infection and COVID-19 development.


Assuntos
COVID-19 , Syzygium , Humanos , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Enzima de Conversão de Angiotensina 2 , Syzygium/metabolismo , SARS-CoV-2 , Peptidil Dipeptidase A/química , Ligação Proteica , Sítios de Ligação , Radicais Livres , Água , Etanol
7.
Foods ; 11(18)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36140996

RESUMO

A collaborative study was undertaken in which five international laboratories participated to determine amino acid fingerprints in 39 authentic nonfat dry milk (NFDM)/skim milk powder (SMP) samples. A rapid method of amino acid analysis involving microwave-assisted hydrolysis followed by ultra-high performance liquid chromatography-ultraviolet detection (UHPLC-UV) was used for quantitation of amino acids and to calculate their distribution. The performance of this rapid method of analysis was evaluated and was used to determine the amino acid fingerprint of authentic milk powders. The distribution of different amino acids and their predictable upper and lower tolerance limits in authentic NFDM/SMP samples were established as a reference. Amino acid fingerprints of NFDM/SMP were compared with selected proteins and nitrogen rich compounds (proteins from pea, soy, rice, wheat, whey, and fish gelatin) which can be potential economically motivated adulterants (EMA). The amino acid fingerprints of NFDM/SMP were found to be affected by spiking with pea, soy, rice, whey, fish gelatin and arginine among the investigated adulterants but not by wheat protein and melamine. The study results establish an amino acid fingerprint of authentic NFDM/SMP and demonstrate the utility of this method as a tool in verifying the authenticity of milk powders and detecting their adulteration.

8.
J Agric Food Chem ; 70(29): 9039-9047, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35820155

RESUMO

The soluble free, soluble conjugated, and insoluble bound phenolic compounds in tomato seeds were extracted and analyzed using ultra-high-performance liquid chromatography-high-resolution mass spectrometry. Total phenolic content (TPC) and free radical scavenging activities along with the antiproliferative effects against the human colorectal cancer cell line (HCT-116) were also examined for the soluble free, soluble conjugated, and insoluble bound phenolic fractions. 13, 7, and 10 compounds were tentatively identified in the soluble free, soluble conjugated, and insoluble bound phenolic fractions, respectively, including indole-3-acetic acid derivatives, flavonoids, phenolic acid, and tyramine-derived hydroxycinnamic acid amines. The insoluble bound phenolic fraction was observed to have a greater TPC value and stronger free radical scavenging activities against ABTS•+, DPPH•, and peroxyl radicals and a stronger inhibitory effect against HCT-116 cells compared with the soluble free and the soluble conjugated fractions. Soluble free and insoluble bound fractions significantly inhibited the proliferation of the HCT-116 cell line, and no antiproliferative effects were observed with the soluble conjugated fraction under the experimental conditions. The results may provide a foundation for future application of tomato seeds as nutraceuticals in dietary supplements and functional foods.


Assuntos
Solanum lycopersicum , Antioxidantes/química , Radicais Livres , Humanos , Solanum lycopersicum/metabolismo , Fenóis/química , Extratos Vegetais/química , Sementes/química
9.
Front Chem ; 7: 539, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31428599

RESUMO

The sluggish kinetics of oxygen evolution reaction (OER) on anode hinders the efficiency of electrochemical water splitting. Electrocatalysts for OER based on non-precious transition metals are highly desirable. Herein, iron and nickel mixed oxides with surface oxygen vacancies were fabricated using NiIIFeII-Prussian blue analog as the precursors by a facile two-step thermal-assisted method. The precursor compositions and calcination temperatures exert great impact on the structure and morphology of the derivatives, as well as the electrocatalytic performances for OER. Both the higher content of Ni ions during the synthesis of precursors and lower calcination temperature favor the electrocatalytic performance of the corresponding derivatives. The porous metal oxides consisting of nickel oxide and nickel ferrite exhibited the remarkable electrocatalytic property toward OER in an alkaline solution, which can be attributed to the nanosized and porous structure, the co-existence of spinel NiFe2O4 and cubic NiO, the high content of surface oxygen vacancies, and the low charge transfer resistance. This study will provide new inspiration for the facile design of low-cost active catalysts for OER in the future.

10.
J Agric Food Chem ; 67(31): 8425-8430, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31322874

RESUMO

In recent years, non-targeted methods have been a popular "buzz" phrase in food fraud detection. Using analytical instrumentation techniques, non-targeted methods have been developed and applied in many food and agricultural situations. However, confusion and misstatements remain regarding how the methods are used. This perspective will discuss the definitions related to non-targeted testing, the procedure of developing and validating methods, the techniques and data analysis, and opportunities and challenges regarding the use of this class of analytical methods. The perspective seeks to provide readers with the latest information regarding recent advances in the use of non-targeted methods.


Assuntos
Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Cromatografia Líquida/métodos , Eletroforese Capilar/métodos , Análise de Alimentos/instrumentação , Humanos , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos
11.
J Agric Food Chem ; 66(32): 8478-8488, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29697263

RESUMO

Proton nuclear magnetic resonance spectra for 66 commercial powdered milk samples were analyzed by principal component analysis, soft independent modeling of class analogy, and pooled, crossed analysis of variance. It was found that the sample type (skim milk powder or non-fat dry milk), the supplier, the production site, the processing temperature (high, medium, or low temperature), and the day of analysis provided statistically significant sources of variation. Interestingly, inexact alignment (deviations of ±0.002 ppm) of the spectral reference peak was a significant source of variation, and fine alignment was necessary before the variation arising from the other experimental factors could be accurately evaluated. Using non-targeted analysis, the lowest detectable adulteration for dicyandiamide, melamine, and sucrose was 0.05%, the lowest detectable adulteration for maltodextrin and urea was 0.5%, the lowest detectable adulteration for ammonium sulfate and whey was 5%, and the lowest adulteration for soy protein isolate was undetectable using methods described herein. The measurement of variance and detection of adulteration were relatively unaffected by the resolution. Similar results were obtained with unbinned data (0.0003 ppm resolution) and binning of 333 data points (0.1 ppm resolution).


Assuntos
Contaminação de Alimentos/análise , Espectroscopia de Ressonância Magnética/métodos , Leite/química , Pós/análise , Animais , Guanidinas/análise , Leite/economia , Pós/química , Proteínas de Soja/análise , Triazinas/análise , Soro do Leite/química
12.
J Agric Food Chem ; 65(28): 5799-5809, 2017 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-28617599

RESUMO

The United States Pharmacopeial Convention has led an international collaborative project to develop a toolbox of screening methods and reference standards for the detection of milk powder adulteration. During the development of adulterated milk powder reference standards, blending methods used to combine melamine and milk had unanticipated strong effects on the near-infrared (NIR) spectrum of melamine. The prominent absorbance band at 1468 nm of melamine was retained when it was dry-blended with skim milk powder but disappeared in wet-blended mixtures, where spray-dried milk powder samples were prepared from solution. Analyses using polarized light microscopy, Raman spectroscopy, dielectric relaxation spectroscopy, X-ray diffraction, and mass spectrometry indicated that wet blending promoted reversible and early Maillard reactions with lactose that are responsible for differences in melamine NIR spectra between wet- and dry-blended samples. Targeted detection estimates based solely on dry-blended reference standards are likely to overestimate NIR detection capabilities in wet-blended samples as a result of previously overlooked matrix effects arising from changes in melamine hydrogen-bonding status, covalent complexation with lactose, and the lower but more homogeneous melamine local concentration distribution produced in wet-blended samples. Techniques used to incorporate potential adulterants can determine the suitability of milk reference standards for use with rapid detection methods.


Assuntos
Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Leite/química , Triazinas/análise , Animais , Bovinos , Lactose/análise , Pós/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos
13.
Food Chem ; 224: 280-288, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28159267

RESUMO

Avenanthramides (AVNs) are a family of nitrogen-containing phenolic compounds produced in oat; AVN 2c, 2p, and 2f are the three major members. An LC-MS/MS method was developed, with the limit of detection (LOD) and the limit of quantitation (LOQ) being, respectively, 0.29ng/mL and 1.96ng/mL for AVN 2c, 0.24ng/mL and 0.60ng/mL for AVE 2p, and 0.42ng/mL and 2.2ng/mL for AVN 2f. The method was validated in oat-containing hot cereal and snack bar samples. The recovery of AVN 2c, 2p, and 2f from these two oat products was 95-113%, and the relative standard deviations ranged from 5% to 9%. This method was used to evaluate oat products and raw oat samples. The effects of location and variety on AVN composition were investigated. The method presented here provides a novel and rapid tool to quantitate the abundance of AVN 2c, 2p, and 2f in oat-containing products.


Assuntos
Avena/química , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , ortoaminobenzoatos/análise , Grão Comestível/química , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
14.
J Nutr Sci ; 5: e16, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27110359

RESUMO

Hypercholesterolaemia is a risk factor for CVD, which is a leading cause of death in industrialised societies. The biosynthetic pathways for cholesterol metabolism are well understood; however, the regulation of circulating cholesterol by diet is still not fully elucidated. The present study aimed to gain more comprehensive understanding of the relationship between circulating cholesterol levels and molecular effects in target tissues using the hamster model. Male golden Syrian hamsters were fed with chow or diets containing 36 % energy from fat with or without 1 % cholesteyramine (CA) as a modulator of circulating cholesterol levels for 35 d. It was revealed that the expression of lanosterol 14α-demethylase (CYP51) instead of 3-hydroxy-3-methyl-glutaryl (HMG)-CoA reductase mRNA expression was responsive to circulating cholesterol in hamsters fed hypercholesterolaemic diets. The high-fat diet increased circulating cholesterol and down-regulated CYP51, but not HMG-CoA reductase. The CA diet decreased cholesterol and increased CYP51 expression, but HMG-CoA reductase expression was not affected. The high-fat diet and CA diet altered the expression level of cholesterol, bile acids and lipid metabolism-associated genes (LDL receptor, cholesterol 7α-hydroxylase (CYP7A1), liver X receptor (LXR) α, and ATP-binding cassette subfamily G member 5/8 (ABCG5/8)) in the liver, which were significantly correlated with circulating cholesterol levels. Correlation analysis also showed that circulating cholesterol levels were regulated by LXR/retinoid X receptor and PPAR pathways in the liver. Using the hamster model, the present study provided additional molecular insights into the influence of circulating cholesterol on hepatic cholesterol metabolism pathways during hypercholesterolaemia.

15.
Food Sci Nutr ; 3(4): 342-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26286710

RESUMO

Mangosteen (Garcinia mangostana) is a tropical fruit cultivated mainly in Southeast Asia. Recent studies have shown mangosteen has many health benefits. In this study, we aimed to determine the effects of a mangosteen-based beverage on antioxidant and anti-inflammatory and immunity biomarkers in plasma of healthy adults. A randomized, double-blind, placebo-controlled clinical trial was conducted using 60 participants, 30 men, and 30 women, ages 18-60. Participants were randomly divided into two groups, placebo and mangosteen groups, with the same number of male and female participants in each group. The trial duration was 30 days. ORAC as an antioxidant biomarker was measured in both groups. It was found that after the 30-day trial, the group given the mangosteen-based drink formula showed 15% more antioxidant capacity in the bloodstream than did the placebo group. As for the inflammatory biomarkers, in the mangosteen group, between the preintervention and postintervention, the C-reactive protein level significantly decreased by 46%, while no significant decreases for the same biomarker was observed in the placebo group. Immunity biomarkers IgA, IgG, IgM, C3 and C4 were not affected in either group. In addition, the effects on hepatic function (Aspartate Aminotransferase and Alanine Aminotransferase) and kidney function (creatinine) were investigated. Our results indicated that after the 30-day consumption of the beverage, there were no side effects on human hepatic and kidney functions. The outcome of this study showed that the mangosteen-based formula significantly increases antioxidant capacity and possesses anti-inflammatory benefits with no side effects on immune, hepatic, and renal functions for long-term consumption.

16.
Food Sci Nutr ; 3(1): 32-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25649891

RESUMO

This study was to investigate the absorption and antioxidant effect of a mangosteen-based functional beverage in humans. The beverage contained mangosteen, aloe vera, green tea, and multivitamins. A randomized, double-blind, placebo-controlled clinical trial was conducted with generally healthy male and female subjects between 18 and 60 years of age. Ten men and 10 women participated in this study. Participants were randomly divided into two groups, treatment and placebo group. Participants received either a daily single dose (245 mL) of the beverage or a placebo. Blood samples were collected from each participant at time points 0, 1, 2, 4, and 6 h. The plasma samples were analyzed by LC/MS for α-mangostin and vitamins B2 and B5. Results indicated that the three analytes were bioavailable, with observed C max at around 1 h. The antioxidant capacity measured with the oxygen radical absorbance capacity (ORAC) assay was increased with a maximum effect of 60% after 1 h, and the elevated antioxidant level lasted at least 6 h. This study demonstrated the bioavailability of α-mangostin and B vitamins from a xanthone-rich beverage and the mechanisms of the increase in plasma antioxidant may be direct effects from antioxidants, enhancement of endogenous antioxidant activity through activation of Nrf2 pathway, and synergism of the antioxidants.

17.
Food Sci Nutr ; 2(6): 647-54, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25493181

RESUMO

ORAC and other in vitro methods have to date proved useful in measuring antioxidant potential in foods. In order to better understand the potential relationship between diet and free radical production/mitigation, an in vivo analytic method can provide new insight into directly measuring reactive oxidant species (ROS). Dihydrorhodamine-6G (DHR6G) is indiscriminate to the various free radicals found in humans, and therefore can be useful in quantifying total ROS in vivo. Our aim was to investigate whether the total ROS in human subjects can be quantified using DHR6G after intake of a blend of antioxidants-rich fruit and vegetable-based materials. Twelve participants were given 100 mg of a proprietary blend of fruit, vegetable, and herb powders and concentrates commercially marketed under the trade name "Spectra™". Blood samples were collected at 0, 60, 120 and 180 min and were subsequently tested for ROS in serum using DHR6G as a fluorescent probe. By quantifying this fluorescence, we were able to measure ROS concentrations in human blood. This method is both reliable and efficient for evaluating the efficacy of antioxidants against ROS in vivo. Our data indicate that eleven participants responded to the intake of Spectra™ by significant decreases of ROS concentrations.

18.
Int J Biol Macromol ; 65: 446-53, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24508920

RESUMO

To explore new antioxidant resource from food, a water-soluble polysaccharide (ALP1) was extracted and purified from the roots of Arctium lappa L. (A. lappa L.) through hot water extraction followed by ethanol precipitation, ion-exchange chromatography and gel filtration. The antioxidant activity of ALP1 was then evaluated in vitro and in vivo. ALP1 was characterized as a fructan composed of fructose and glucose in the ratio of 13.0:1.0, with an average molecular weight of 4600 Da. The linkages in ALP1 were →1)-Fruf-(2→, Fruf-(2→ and Glcp-(1→. In vitro antioxidant assays demonstrated that ALP1 possessed moderate ABTS(+) scavenging activity, strong hydroxyl radical scavenging activity and strong ferrous ion chelating activity. In in vivo antioxidant assays, ALP1 administration significantly enhanced antioxidant enzyme activities and total antioxidant capacity, as well as decreased the levels of malondialdehyde (MDA) in both the serum and liver of aging mice. These results suggest that ALP1 has potential as a novel natural antioxidant in food industry and pharmaceuticals.


Assuntos
Arctium/química , Sequestradores de Radicais Livres/farmacologia , Frutanos/farmacologia , Raízes de Plantas/química , Animais , Fenômenos Químicos , Feminino , Sequestradores de Radicais Livres/química , Radicais Livres/química , Frutanos/química , Camundongos
19.
Food Chem ; 151: 472-9, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24423559

RESUMO

Radish microgreens constitute a good source of bioactive compounds; however, they are very delicate and have a short shelf life. In this study, we investigated the impact of light exposure and modified atmosphere packaging on sensorial quality, bioactive compound concentrations and antioxidant capacity of radish microgreens during storage. Results showed that light exposure during storage increased the amount of ascorbic acid and had no effect on α-tocopherol or total phenolic concentrations. Dark storage resulted in higher hydroxyl radical scavenging capacity and carotenoid retention. No significant differences were found for relative 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity between light and dark treatments. Radish microgreens in bags of 29.5 pmol s(-1) m(-2) Pa(-1) oxygen transmission rate (OTR) maintained better quality than those within laser microperforated bags. In conclusion, light exposure accelerated deterioration of radish microgreens, while dark storage maintained quality; and application of OTR bags was beneficial in extending shelf life.


Assuntos
Antioxidantes/química , Raphanus/química , Temperatura Baixa , Armazenamento de Alimentos , Luz , Fenóis/análise , Temperatura
20.
J Agric Food Chem ; 61(24): 5772-82, 2013 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-23697397

RESUMO

Hypercholesterolemia is one of the major factors contributing to the risk of cardiovascular disease (CVD), which is the leading cause of death in developed countries. Consumption of soy foods has been recognized to lower the risk of CVD, and phytochemicals in soy are believed to contribute to the health benefits. Glyceollin is one of the candidate phytochemicals synthesized in stressed soy that may account for many unique biological activities. In this study, the in vivo cholesterol-lowering effect of glyceollins was investigated. Male golden Syrian hamsters were fed diets including (1) 36 kcal% fat diet, (2) 36 kcal% fat diet containing 250 mg/kg diet glyceollins, or (3) chow for 28 days. Hepatic cholesterol esters and free cholesterol, hepatic total lipid content, plasma lipoproteins, fecal bile acid, fecal total cholesterol, and cholesterol metabolism related gene expressions were measured. Glyceollin supplementation led to significant reduction of plasma VLDL, hepatic cholesterol esters, and total lipid content. Consistent with changes in circulating cholesterol, glyceollin supplementation also altered expression of the genes related to cholesterol metabolism in the liver. In contrast, no change in plasma LDL and HDL, fecal bile acid, or cholesterol content was observed. The cholesterol-lowering effect of glyceollins appeared not to go through the increase of bile excretion. These results supported glyceollins' role as novel soy-derived cholesterol-lowering phytochemicals that may contribute to soy's health effects.


Assuntos
Anticolesterolemiantes/uso terapêutico , Suplementos Nutricionais , Modelos Animais de Doenças , Glycine max/química , Hipercolesterolemia/prevenção & controle , Pterocarpanos/uso terapêutico , Sementes/química , Animais , Cricetinae , Dieta Hiperlipídica/efeitos adversos , Hipercolesterolemia/etiologia , Masculino , Mesocricetus
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