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1.
Food Funct ; 10(12): 8195-8207, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31701112

RESUMO

Altering sn-fatty acid position of glycerol mono-oleate (GMO) from sn-1 to sn-2 decreases fatty acid bioaccessibility by 25.9% providing possible strategies to tailor lipemic responses of food emulsions. Lipid digestion kinetics and fatty acid bioaccessibility of monomodal O/W emulsions stabilized at their minimum surfactant concentration (0.5 < MSC > 0.7 (w/w)) were studied in the TNO Intestinal Model (TIM-1) gastrointestinal (GI) tract. No significant differences were observed between induction times nor rate constants when using 1-GMO and 1-GMS, Span 60, Tween 60 and Tween 80 as surfactants in O/W emulsions, as determined by fitting a three-parameter shifted logistic model to the cumulative bioaccessibility. Comparable trends were observed between area under the curve (AUC) of the absolute bioaccessibility and total overall bioaccessibility.


Assuntos
Lipídeos/química , Tensoativos/química , Água/química , Digestão , Emulsões/química , Emulsões/metabolismo , Trato Gastrointestinal/química , Trato Gastrointestinal/metabolismo , Cinética , Metabolismo dos Lipídeos , Modelos Biológicos , Peso Molecular , Polissorbatos/química , Polissorbatos/metabolismo , Tensoativos/metabolismo , Água/metabolismo
2.
Pharmaceutics ; 11(4)2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30987004

RESUMO

Phyto-phospholipid complexes have been developed as a common way of improving the oral bioavailability of poorly absorbable phyto-pharmaceuticals; however, the complexation with phospholipids can induce positive or negative effects on the bioaccessibility of such plant-derived active ingredients in different parts of the gastrointestinal tract (GIT). The purpose of this study was to investigate the effects of phospholipid complexation on the bioaccessibility of a rosmarinic acid-phospholipid complex (RA-PLC) using the TNO dynamic intestinal model-1 (TIM-1). Preparation of RA-PLC was confirmed using X-ray diffraction, Fourier-transform infrared spectroscopy, partition coefficient measurement, and Caco-2 monolayer permeation test. Bioaccessibility parameters in different GIT compartments were investigated. Complexation by phospholipids reduced the bioaccessibility of RA in jejunum compartment, while maintaining the ileum bioaccessibility. The overall bioaccessibility of RA-PLC was lower than the unformulated drug, suggesting that the improved oral absorption from a previous animal study could be considered as a net result of decreased bioaccessibility overwhelmed by enhanced intestinal permeability. This study provides insights into the effects of phospholipid on the bioaccessibility of hydrophilic compounds, and analyzes them based on the relationship between bioaccessibility, membrane permeability, and bioavailability. Additionally, TIM-1 shows promise in the evaluation of dosage forms containing materials with complicated effects on bioaccessibility.

3.
J Agric Food Chem ; 64(8): 1712-9, 2016 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-26853559

RESUMO

Unextractable phenolics from plant foods and their role in health benefits have become increasingly important. Meal residues of three quinoa seeds free of fat and extractable phenolics were subjected to acid, alkaline, and enzymatic hydrolyses. The total and individual phenolic compounds released were analyzed, and 19 phenolics, predominantly phenolic acids and several flavonoids, were identified. The concentration of bound phenolics was highest in black quinoa followed by red and white, regardless of the hydrolysis method. Higher phenolic contents also showed stronger antioxidant activities and inhibition of α-glucosidase and pancreatic lipase activities. Carbohydrases, that is, pectinase, xylanase and feruloyl esterase, which effectively liberated bound phenolics are known to be secreted by colonic bacteria, suggesting potential antioxidant and anti-inflammatory effects by these compounds in the large intestine during colonic fermentation. These results can also be applied to treat foods high in bound phenolics to enhance bioaccessibility.


Assuntos
Chenopodium quinoa/química , Inibidores Enzimáticos/química , Lipase/antagonistas & inibidores , Fenóis/química , Extratos Vegetais/química , Inibidores Enzimáticos/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Lipase/química , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Sementes/química , alfa-Glucosidases/análise
4.
J Agric Food Chem ; 64(5): 1103-10, 2016 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-26760897

RESUMO

Various fatty acids, tocopherols, carotenoids, and their respective antioxidant contributions in 7 amaranth seed and 11 quinoa seed samples along with a new evaluation method are reported. The lipid yield was 6.98-7.22% in amaranth seeds and 6.03-6.74% in quinoa seeds, with unsaturated fatty acids (UFAs) being the predominant fatty acids, 71.58-72.44% in amaranth seeds and 81.44-84.49% in quinoa seeds, respectively. Carotenoids, mainly lutein and zeaxanthin, are confirmed for the first time in amaranth seeds, while ß-carotene is reported first in quinoa seeds. The predominant tocopherols in amaranth seeds are δ- and α-tocopherol, whereas γ- and α-tocopherol are the primary tocopherols in quinoa seeds. UFAs, carotenoids, and tocopherols showed good correlation with antioxidant activity. All of the amaranth seeds demonstrated lower overall lipophilic quality than quinoa seeds, with the AS1 and QS10 cultivars providing the highest scores for amaranth and quinoa seeds, respectively. Results from this study will contribute to developing quinoa seeds and related functional foods with increased benefits.


Assuntos
Amaranthus/química , Carotenoides/química , Chenopodium quinoa/química , Ácidos Graxos/química , Extratos Vegetais/química , Tocoferóis/química , Amaranthus/crescimento & desenvolvimento , Chenopodium quinoa/crescimento & desenvolvimento , Valor Nutritivo , Ontário , Sementes/química , Sementes/crescimento & desenvolvimento
5.
J Agric Food Chem ; 63(48): 10448-58, 2015 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-26479447

RESUMO

Cranberry beans from regular (RR) and nondarkening (CND) genotypes were pressure cooked, and free, conjugated, and bound phenolics were analyzed. Simulated in vitro gastrointestinal digestion was used to assess the bioaccessibility of these phenolic fractions. Total phenolic content decreased after cooking and digestion, whereas individual phenolic compounds were affected differently. Cooking significantly increased the release of bound ferulic and sinapic acids and flavanols, whereas digestion released p-coumaric, ferulic, and sinapic acids in both genotypes, and p-hydroxybenzoic acid, epicatechin, and catechin in only RR. Bioaccessibility of phenolics in RR and CND was 8.75 and 14.69%, respectively. Difference in total phenolics was smaller after digestion, and enzymes potentially secreted by colonic bacteria released similar amounts of phenolic acids in both varieties. Resistant and slowly digestible starch contents showed no differences between RR and CND. These results suggest that the lower phenolic content in raw CND may not completely negate its impact on gut health.


Assuntos
Digestão , Phaseolus/metabolismo , Fenóis/química , Antioxidantes , Culinária , Humanos , Phaseolus/química , Fenóis/metabolismo , Amido/metabolismo
6.
Food Chem ; 185: 298-308, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25952872

RESUMO

Cranberry beans (Phaseolus vulgaris L.) from 7 different cultivars were characterized for phytochemicals and assessed for antioxidant activities. In vitro colorimetric methods were used to measure total phenolic (TPC) and total proanthocyanidin (PAC) contents. Free, conjugated and bound phenolic acids and flavonoids were also identified and quantified using HPLC-DAD/ESI-MS(n). Regular-darkening (RD) seeds contained higher TPC, PAC and flavonoids which were absent in the non-darkening (ND) seeds. Bound and conjugated phenolics in RD and ND mainly included cinnamic and benzoic acids. DPPH, FRAP and ORAC showed strong positive correlation with TPC, PAC, and with specific phenolics such as free catechin and bound p-hydroxybenzoic acid. Lipophilic extracts were rich in polyunsaturated fatty acids (69.20-76.89%). Carotenoid and tocopherol were limited to γ-tocopherol and ß-carotene. Results from this study can contribute to the development of cranberry bean cultivars with increased health benefits and addresses specific phenolic contributors to antioxidant activity.


Assuntos
Antioxidantes/análise , Phaseolus/química , Fenóis/análise , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Compostos Fitoquímicos/análise , Extratos Vegetais/análise , Proantocianidinas/análise , Sementes/química
7.
Regul Toxicol Pharmacol ; 71(2): 186-97, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25549549

RESUMO

The objectives of this clinical study were to evaluate changes in tobacco product use behavior and levels of selected biomarkers of exposure (BOEs) for smokers who switched to one of six conditions during clinical confinement: exclusive use of; Camel Snus, Sticks, Strips or Orbs, controlled Dual use of cigarettes and Camel Snus, or tobacco abstinence. The controlled Dual use (DU) condition mandated a 60% reduction in cigarettes smoked per day (CPD). 167 healthy U.S. male and female smokers were randomized to the six groups (n=25-30/group). Subjects smoked their usual brand of cigarette for 1 day prior to switching to their designated intervention condition. Levels of thirty-two BOEs in plasma, whole blood, urine and feces were determined before and after switching. Questionnaires that scored nicotine dependence and withdrawal discomfort were also administered. After 5 days, exclusive Snus, Sticks, Strips, or Orbs use averaged 6.1, 5.9, 13.5, and 8.5 units/day, respectively. DU subjects smoked 7.6 CPD and used 3.2 Snus pouches/day, on average. After 5 days, substantial reductions of most biomarkers, including nicotine, were observed in all groups. Toxicant exposures were similar to being tobacco abstinent after switching exclusively to Camel Snus, Sticks, Strips or Orbs. DU reductions were more modest.


Assuntos
Abandono do Hábito de Fumar , Fumar/epidemiologia , Fumar/metabolismo , Tabagismo/epidemiologia , Tabagismo/metabolismo , Tabaco sem Fumaça , Adulto , Biomarcadores/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tabagismo/diagnóstico , Tabaco sem Fumaça/estatística & dados numéricos , Adulto Jovem
8.
Food Chem ; 166: 380-388, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25053071

RESUMO

Quinoa (Chenopodium quinoa Willd.) is known for its exceptional nutritional value and potential health benefits. The present study identified the composition of different forms of extractable phenolics and betacyanins of quinoa cultivars in white, red and black, and how they contribute to antioxidant activities. Results showed that at least 23 phenolic compounds were found in either free or conjugated forms (liberated by alkaline and/or acid hydrolysis); the majority of which were phenolic acids, mainly vanillic acid, ferulic acid and their derivatives as well as main flavonoids quercetin, kaempferol and their glycosides. Betacyanins, mainly betanin and isobetanin, were confirmed for the first time to be the pigments of the red and black quinoa seeds, instead of anthocyanins. Darker quinoa seeds had higher phenolic concentration and antioxidant activity. Findings of these phenolics, along with betacyanins in this study add new knowledge to the functional components of quinoa seeds of different cultivar background.


Assuntos
Betacianinas/química , Chenopodium quinoa/química , Flavonoides/análise , Fenóis/análise , Sementes/química , Genótipo , Polifenóis
9.
Food Chem ; 172: 862-72, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25442631

RESUMO

Phenolic extracts from 20 Canadian lentil cultivars (Lens culinaris) were evaluated for total phenolic contents and composition, antioxidant activities (DPPH, FRAP, ORAC), and inhibitory properties against α-glucosidase and pancreatic lipase. Twenty one phenolic compounds were identified in the present study, with the majority being flavonoids, including kaempeferol glycosides, catechin/epicatechin glucosides and procyanidins. These phenolic compounds not only contributed significantly to the antioxidant activities, but they were also good inhibitors of α-glucosidase and lipase, two enzymes, respectively, associated with glucose and lipid digestion in the human intestine, thus contributing significantly to the control of blood glucose levels and obesity. More interestingly, it was the flavonols, not the flavanols, which showed the inhibitory activities against α-glucosidase and pancreatic lipase. Our result provides supporting information for developing lentil cultivars and functional foods with improved health benefits and suggests a potential role of lentil consumption in managing weight and control of blood glucose.


Assuntos
Antioxidantes/química , Inibidores Enzimáticos/química , Lens (Planta)/química , Lipase/antagonistas & inibidores , Fenóis/química , Extratos Vegetais/química , Animais , Antioxidantes/isolamento & purificação , Canadá , Inibidores Enzimáticos/isolamento & purificação , Flavonoides/análise , Alimento Funcional/análise , Humanos , Lens (Planta)/classificação , Lipase/análise , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Ratos , Suínos , alfa-Glucosidases/análise
10.
Food Chem ; 174: 502-8, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25529712

RESUMO

Composition of fatty acids, tocopherols, tocotrienols, and carotenoids, and their contribution to antioxidant activities were investigated in seeds of three coloured quinoa cultivars (white, red and black). The major components and individual compounds were significantly different, and their concentrations were higher in darker seeds (p < 0.05). The oil yield was 6.58-7.17% which contained predominantly unsaturated fatty acids (89.42%). The ratio of omega-6/omega-3 fatty acid was ca. 6/1. The total tocopherol content ranged from 37.49 to 59.82 µg/g and mainly consisted of γ-tocopherol. Trace amount of α- and ß-tocotrienols was also found. Black quinoa had the highest vitamin E followed by red and white quinoas. Carotenoids, mainly trans-lutein (84.7-85.6%) and zeaxanthin were confirmed for the first time in quinoa seeds, and the concentration was also the highest in black seeds. The antioxidant activities of lipophilic extracts were positively correlated with polyunsaturated fatty acids, total carotenoids and total tocopherols.


Assuntos
Carotenoides/química , Chenopodium quinoa/química , Ácidos Graxos/química , Tocoferóis/química , Vitamina E/análogos & derivados , Carotenoides/análise , Chenopodium quinoa/genética , Ácidos Graxos/análise , Genótipo , Sementes/química , Tocoferóis/análise , Vitamina E/análise , Vitamina E/química
11.
J Agric Food Chem ; 62(52): 12585-94, 2014 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-25474757

RESUMO

The phytochemicals and antioxidant activity in lipophilic and hydrophilic (extractable and bound) fractions of lentils before and after domestic cooking were investigated. The hydrophilic fractions in lentils contributed much more to the antioxidant activity than the lipophilic fraction. The phenolic content of lentils was mainly composed of extractable compounds. Significant changes (P < 0.05) in carotenoid, tocopherol, total phenolic, and condensed tannin contents of both extractable and bound phenolics fractions, as well as in antioxidant activities, were found in lentils before and after cooking. More specifically, cooking was found to favor the release of carotenoids and tocopherols and flavonols (kaempferol glycosides), but led to losses of flavanols (monomeric and condensed tannin). Whereas reduced flavanols and other phenolic compounds may have negatively affected the antioxidant activity, other components, especially the lipophilic antioxidants, were increased. The present study suggests that incorporation of cooked lentils into the diet will not cause significant loss to the phytochemical antioxidants and thus will retain the potential health benefits.


Assuntos
Antioxidantes/química , Carotenoides/química , Ácidos Graxos/química , Lens (Planta)/química , Fenóis/química , Extratos Vegetais/química , Tocoferóis/química , Culinária , Temperatura Alta
12.
J Agric Food Chem ; 62(52): 12610-9, 2014 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-25465272

RESUMO

Composition of lipophilic phytochemicals including fatty acids, tocopherols, and carotenoids in leaves of 6 quinoa and 14 amaranth cultivars was analyzed. The oil yields in quinoa and amaranth leaves were only 2.72-4.18%, which contained mainly essential fatty acids and had a highly favorable ω-3/ω-6 ratio (2.28-3.89). Pro-vitamin A carotenoids, mainly α- and ß-carotenes, and xanthophylls, predominantly lutein and violaxanthin, were found in all samples. The primary tocopherol isomers present in both quinoa and amaranth leaves were α- and ß-tocopherols. Added to the discussion on the lipophilic nutrients was the normalization of ω-3/ω-6 ratio, α-tocopherol equivalents, and carotenoids, in an attempt to establish a novel system for evaluation of the overall quality attributes of lipophilic nutrients (NQ value). The NQ value, but not the individual components, was highly correlated with all the antioxidant activities, supporting the ranking order of the potential nutritional quality of quinoa and amaranth leaves based on this new method.


Assuntos
Amaranthus/química , Carotenoides/química , Chenopodium quinoa/química , Lipídeos/química , Extratos Vegetais/química , Folhas de Planta/química , Tocoferóis/química , Ácidos Graxos/química , Isomerismo , Valor Nutritivo
13.
J Agric Food Chem ; 62(20): 4754-61, 2014 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-24796380

RESUMO

A common protocol for the extraction of phenolic aglycons or bound phenolics in plants generally involves hydrothermal hydrolysis in an aqueous methanol or ethanol solution containing 2-4 N HCl. However, as shown in the present study, this process also forms 5-(hydroxymethyl)furan-2-carbaldehyde (HMF) and its derivative products 5-(methoxymethyl)furan-2-carbaldehyde (MMF) and 5-(ethoxymethyl)furan-2-carbaldehyde (EMF), as identified by HPLC-DAD-ESI-MS/MS and NMR. These compounds are commonly misidentified as phenolics due to similar UV absorption at 280 nm. In this study, production of HMF, MMF, and EMF was shown to be dependent on the solvent condition and duration and temperature of hydrolysis. Fruits and vegetables produced HMF more readily than grains. HMF and its derivatives were subjected to various spectrophotometric antioxidant assays [2-diphenyl-1-picryhydrazyl radical scavenging activity (DPPH), ferric-reducing antioxidant power (FRAP), and oxygen radical absorbing capacity (ORAC)] and displayed antioxidant activity mainly in the ORAC assay. Results of this study help avoid overestimation of phenolic content and antioxidant activities of plant foods.


Assuntos
Antioxidantes/química , Frutas/química , Furaldeído/análogos & derivados , Fenóis/química , Extratos Vegetais/química , Verduras/química , Ácidos/química , Cromatografia Líquida de Alta Pressão , Furaldeído/química , Hidrólise , Espectrometria de Massas em Tandem
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