Pomegranate ellagitannins inhibit α-glucosidase activity in vitro and reduce starch digestibility under simulated gastro-intestinal conditions.
Int J Food Sci Nutr
; 66(1): 85-92, 2015 Feb.
Article
em En
| MEDLINE
| ID: mdl-25519249
ABSTRACT
Pomegranate extract was tested for its ability to inhibit α-amylase and α-glucosidase activity. Pomegranate extract strongly inhibited rat intestinal α-glucosidase in vitro whereas it was a weak inhibitor of porcine α-amylase. The inhibitory activity was recovered in an ellagitannins-enriched fraction and punicalagin, punicalin, and ellagic acid were identified as α-glucosidase inhibitors (IC(50) of 140.2, 191.4, and 380.9 µmol/L, respectively). Kinetic analysis suggested that the pomegranate extract and ellagitannins inhibited α-glucosidase activity in a mixed mode. The inhibitory activity was demonstrated using an in vitro digestion system, mimicking the physiological gastro-intestinal condition, and potatoes as food rich in starch. Pre-incubation between ellagitannins and α-glucosidase increased the inhibitory activity, suggesting that they acted by binding to α-glucosidase. During digestion punicalin and punicalagin concentration decreased. Despite this loss, the pomegranate extract retained high inhibitory activity. This study suggests that pomegranate ellagitannins may inhibit α-glucosidase activity in vitro possibly affecting in vivo starch digestion.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Extratos Vegetais
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Lythraceae
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Trato Gastrointestinal
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Taninos Hidrolisáveis
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Inibidores Enzimáticos
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Alfa-Glucosidases
Limite:
Animals
Idioma:
En
Revista:
Int J Food Sci Nutr
Assunto da revista:
CIENCIAS DA NUTRICAO
Ano de publicação:
2015
Tipo de documento:
Article
País de afiliação:
Itália