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1.
Molecules ; 26(2)2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33467593

RESUMO

Among bioactive phytochemicals, ellagic acid (EA) is one of the most controversial because its high antioxidant and cancer-preventing effects are strongly inhibited by low gastrointestinal absorption and rapid excretion. Strategies toward an increase of solubility in water and bioavailability, while preserving its structural integrity and warranting its controlled release at the physiological targets, are therefore largely pursued. In this work, EA lysine salt at 1:4 molar ratio (EALYS), exhibiting a more than 400 times increase of water solubility with respect to literature reports, was incorporated at 10% in low methoxylated (LM) and high methoxylated (HM) pectin films. The release of EA in PBS at pH 7.4 from both film preparations was comparable and reached 15% of the loaded compound over 2 h. Under simulated gastric conditions, release of EA from HM and LM pectin films was minimal at gastric pH, whereas higher concentrations-up to 300 µM, corresponding to ca. 50% of the overall content-were obtained in the case of the HM pectin film after 2 h incubation at the slightly alkaline pH of small intestine environment, with the enzyme and bile salt components enhancing the release. EALYS pectin films showed a good prebiotic activity as evaluated by determination of short chain fatty acids (SCFAs) levels following microbial fermentation, with a low but significant increase of the effects produced by the pectins themselves. Overall, these results highlight pectin films loaded with EALYS salt as a promising formulation to improve administration and controlled release of the compound.


Assuntos
Preparações de Ação Retardada/química , Ácido Elágico/administração & dosagem , Ácido Elágico/química , Pectinas/química , Disponibilidade Biológica , Composição de Medicamentos/métodos , Fezes/microbiologia , Fermentação , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos , Hidroxilação , Absorção Intestinal/efeitos dos fármacos , Pectinas/classificação , Solubilidade
3.
J Agric Food Chem ; 49(6): 3051-7, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11410008

RESUMO

This study was undertaken to characterize the pectin from four citrus species and to determine their in vitro inhibitory activities on the binding of fibroblast growth factor (FGF) to the FGF receptor (FGFR). Pectin from various parts of lemon, grapefruit, tangerine, and orange were isolated and characterized. Tangerine had the highest pectin content among the four citrus species. Segment membrane contained as much as or more pectin than flavedo/albedo. Anhydrogalacturonic content was highest in pectin from segment membrane of tangerine and flavedo/albedo of grapefruit. Lemon pectin contained the highest methoxyl content (MC), and grapefruit contained the largest proportion of lower molecular weight (<10000 Da) pectin. Tangerine contained the highest neutral sugar in both flavedo/albedo and segment membrane. The interdependency of heparin on factor-receptor interaction provides a means for identifying new antagonists of growth factor activity and thus for treatment of various diseases. These results showed that pectin significantly inhibited the binding of FGF-1 to FGFR1 in the presence of 0.1 microg/mL heparin. The pectin from the segment membrane of lemon was the most potent inhibitor. The inhibition activity was significantly correlated with sugar content, MC, and size of pectin. Kinetic studies revealed a competitive nature of pectin inhibition with the heparin, a crucial component of the FGF signal transduction process. The observation that the heparin-dependent biological activity of FGF signal transduction is antagonized by citrus pectin should be further investigated for the use of these pectins as anti-growth factor agents for potential health benefits.


Assuntos
Citrus/química , Fatores de Crescimento de Fibroblastos/metabolismo , Pectinas/análise , Receptores de Fatores de Crescimento de Fibroblastos/antagonistas & inibidores , Fatores de Crescimento de Fibroblastos/química , Heparina/química , Heparina/metabolismo , Cinética , Peso Molecular , Pectinas/classificação , Transdução de Sinais
4.
Arch Latinoam Nutr ; 47(3): 208-16, 1997 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-9673674

RESUMO

Great amounts of agroindustrial wastes rich in polysaccharides, such as pectic substances, are produced worldwide. Some of these wastes are used for the production of pectin. Currently, pectin is extracted at industrial scale by physicochemical means, but lately new biotechnological alternatives have been developed. In this review, the principal characteristics of pectic substances and pectic enzymes are described. The traditional physicochemical method for the pectin extraction is described and the new biotechnological (microbial and enzymatic) methods for pectin extraction are discussed and commented as well.


Assuntos
Pectinas/isolamento & purificação , Plantas Comestíveis/química , Biotecnologia/métodos , Microbiologia Industrial/métodos , Pectinas/química , Pectinas/classificação
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