Nigerian propolis: chemical composition, antioxidant activity and α-amylase and α-glucosidase inhibition

Abstract

Propolis is an attractive natural ingredient to design health products due to its pharmacological effects. Our chemical investigation of a polar extract of Nigerian propolis (NP) led the isolation and identification of five isoflavonoids (1-4, 6), one diarylpropane (5) and one prenylated flavanone (7) by the combination of chromatographic and spectroscopic techniques. Compounds 1, 4 and 7 were found to be the main markers in NP (8.0, 5.0 and 4.0 mg/g of dry extract, respectively). Moreover, NP and its phenolic constituents exhibited in vitro free radical scavenging activity together with a promising antidiabetic effect against α-amylase and α-glucosidase enzymes. Finally, NP showed also a moderate inhibition of Helicobacter pylori growth. These results suggested that NP could be a good candidate in nutraceuticals and food products.

Keywords:

• Nigerian propolis
• polyphenols
• free-radical scavenging activity
• α-amylase and α-glucosidase enzymes
• Helicobacter pylori

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study was financially supported by the University of Lagos, Nigeria grant (CRC No: M2012/02).