α-amylase and α-glucosidase inhibitors isolated from Triticum aestivum L. sprouts

Abstract

Inhibitory activities of the methanol extract from Triticum aestivum L. sprouts were examined against α-amylase and α-glucosidase. The active constituents of T. aestivum were isolated by chromatographic techniques and identified as γ-aminobutyric acid and ferulic acid on the basis of IR and NMR. γ-Aminobutyric acid and ferulic acid showed the high inhibitory activities with IC50 values of 5.4±0.2 and 9.5±0.1 mM against α-amylase, and 1.4±0.4 and 4.9±0.3 mM against α-glucosidase. The methoxy group on the hydroxycinnamic acid of ferulic acid derivatives played important functions in the α-amylase and α-glucosidase inhibitory activities. Based on the IC50 values of nitrite-scavenging activity, ferulic acid (98±3.9 μg/mL) was the most effective constituent, followed by γ-aminobutyric acid (182± 4.2 μg/mL), sinapic acid (301±2.7 μg/mL), and p-coumaric acid (454±2.2 μg/mL). These results indicate that γ-aminobutyric acid and ferulic acid could be useful as preventative agents, and possibly therapeutic modalities for the treatment of metabolic diseases. © 2012 The Korean Society for Applied Biological Chemistry.