A comparative study on the estimated glycemic index (eGI), phenolic constituents, antioxidative and potential antihyperglycemic effects of different parts of ripe Citrus paradisi fruit

  • Folake L. Oyetayo
  • Seun F. AkomolafeEmail author
  • Iyabo F. Oladapo
Research Article


This study compared the estimated glycemic index, antioxidant, and α-amylase and α-glucosidase inhibitory properties of ripe Citrus paradisi fruit’s parts, as well as their phenolic composition by employing high performance liquid chromatography fixed with diode array detector. The result revealed that C. paradisi fruit’s peel exhibited significantly lowest glycemic index, highest antioxidant and inhibitory effects on the activities of α-amylase and α-glucosidase, with concomitant highest polyphenol constituents compared to other parts of the fruit. Thus, being a waste product of the fruit, it could be a prospective source of natural products for functional food development, nutraceuticals or dietary supplement for the management of diabetes, due to the low glycemic index, antioxidant and inhibition of α-glucosidase and α-amylase activities.


Citrus paradisi fruit α-Amylase α-Glucosidase Antioxidant Glycemic index Phenolic constituents 


Compliance with ethical standards

Ethical statement

All procedures performed in studies involving animals were in accordance with the Institutional Animal Ethical Committee. The ethical clearance number is AFO034SAKO04. All efforts were made to minimize the number of animals and their suffering.

Conflict of interest

This manuscript described has not been published before; not under consideration for publication anywhere else; and has been approved by all co-authors.

Supplementary material

Supplementary material 1 (PDF 324 KB)

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Supplementary material 2 (PDF 329 KB)

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Supplementary material 2 (JPEG 328 kb)

Supplementary material 2 (PDF 329 KB)

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Supplementary material 3 (JPEG 328 kb)


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Copyright information

© Institute of Korean Medicine, Kyung Hee University 2018

Authors and Affiliations

  1. 1.Department of BiochemistryEkiti State UniversityAdo EkitiNigeria

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