Spectrophotometric and voltammetric assessment of totalflavonoid and phenolic content of Cucurbita species and theirantioxidant activity

Authors

  • C. Andrew
    Department of Chemistry, Faculty of Physical Sciences, Federal University Wukari, PMB 1020, Wukari, Taraba State, Nigeria
  • S. W. Ngbo
    Department of Chemistry, Faculty of Physical Sciences, Federal University Wukari, PMB 1020, Wukari, Taraba State, Nigeria
  • L. O. Edmund
    Department of Chemistry, Faculty of Physical Sciences, Federal University Wukari, PMB 1020, Wukari, Taraba State, Nigeria
  • P. S. Moses
    Department of Chemistry, Faculty of Physical Sciences, Federal University Wukari, PMB 1020, Wukari, Taraba State, Nigeria
  • P. Y. Olekwu
    Department of Chemistry, Faculty of Physical Sciences, Federal University Wukari, PMB 1020, Wukari, Taraba State, Nigeria
  • A. I. Onen
    Department of Chemistry, Faculty of Physical Sciences, Federal University Wukari, PMB 1020, Wukari, Taraba State, Nigeria

Keywords:

Antioxidants, Voltammetry, Spectroscopy, Cucurbita

Abstract

Evaluating the antioxidant properties of edible fruits is central to understanding their potential health benefits. We determined the antioxidant capacity and total phenolic and flavonoid contents of Cucurbita pepo and Cucurbita moschata using cyclic voltammetry and spectrophotometric assays, including 2,2'-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant potential (FRAP). A microwave-assisted method was used for extraction with n-hexane and methanol as solvents. The methanolic extracts produced higher phenolic contents in C. pepo (122.40 μg gallic acid equivalent (GA Eq)/mg) and C. moschata (132.4 μg GA Eq/mg) than the n-hexane extracts. Higher flavonoid levels were found in the methanolic extract of C. pepo (266.7 μg Q Eq/mg) and the n-hexane extract of C. moschata (177 μg Q Eq/mg). The DPPH assay showed higher percentage inhibition of free radicals in the n-hexane extracts of C. pepo (66.732 ± 6.976%) and C. moschata (58.425 ± 5.340%) than in the methanolic extracts. The FRAP assay indicated that the n-hexane extract of C. pepo had higher reducing power (∼98.0%) than the methanolic extract (∼77.5%), whereas the methanolic extract of C. moschata had higher reducing potential (∼106.9%) than the n-hexane extract (∼86.2%). The voltammetric assay showed that C. moschata had higher antioxidant activity (1.13 ± 0.061 μg GA Eq/mg and 4.19 ± 0.10 μg ascorbic acid equivalent (AA Eq)/mg) than C. pepo extracts (0.65 ± 0.004 μg GA Eq/mg and 3.40 ± 0.0068 μg AA Eq/mg). These findings provide insight into the antioxidant potential of two Cucurbita species and may support broader antioxidant research in food science and technology.

Dimensions

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FIG 4

Published

2026-06-02

How to Cite

Spectrophotometric and voltammetric assessment of totalflavonoid and phenolic content of Cucurbita species and theirantioxidant activity. (2026). African Scientific Reports, 5(2), 445. https://doi.org/10.46481/asr.2026.5.2.445

Issue

Volume 5, Issue 2, August 2026

Section

CHEMISTRY SECTION
Copyright & Licensing

Copyright (c) 2026 C. Andrew, S. W. Ngbo, L. O. Edmund, P. S. Moses, P. Y. Olekwu, A. I. Onen

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

How to Cite

Spectrophotometric and voltammetric assessment of totalflavonoid and phenolic content of Cucurbita species and theirantioxidant activity. (2026). African Scientific Reports, 5(2), 445. https://doi.org/10.46481/asr.2026.5.2.445

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