Phytoconstituents and Antioxidant Activity of the Stem Bark of Pentaclethra macrophylla (Fabaceae)

Phytoconstituents and Antioxidant Activity of the Stem Bark of Pentaclethra macrophylla (Fabaceae)

Augustine Ajibogun Ahmadu*1, Aniefiok Udobre2, Ini Ekpe3, Florence Tarfa4 and Patricia
Odumosu5

 

  1. Department of Pharmaceutical and Medicinal Chemistry, Faculty of Pharmaceutical
    Sciences, Veritas University, Bwari-Abuja, Nigeria.
  2. Department of Pharmaceutical and Medicinal Chemistry, Faculty of Pharmacy, University of Uyo, Uyo, Nigeria.
  3. Department of Biochemistry, Faculty of Pure and Applied Sciences, Veritas University Bwari, Abuja, Nigeria
  4. Department of Medicinal Plant and Quality Control, National Institute for Pharmaceutical
    Research and Development, Idu, Abuja, Nigeria.
  5. Department of Pharmaceutical and Medicinal Chemistry, Faculty of Pharmaceutical Sciences, University of
    Jos, Jos, Nigeria.

 

Key words:

Antioxidant activity, 11-galloylbergenin, Myricetin-3-O-glucoside, LC-MS

 

 

 

 

*Corresponding author: ahmadu2001@yahoo.com;
DOI:https://doi.org/10.61594/tnpr.v6(2).2025.126

Page No: 114-123
Volume: 6, Issue 2, 2025
Trends in Natural Products Research
Copy Right: NAPREG

Abstract

Pentaclethra macrophylla is known for its nutritional and medicinal properties. Despite its wide usage, little information is known about the antioxidant potential of the stem bark extract and its fractions. This work reports the antioxidant activity of ethyl acetate and n-butanol soluble fractions, as well as chromatographic fractions, and the identification of probable antioxidant compounds using LC-MS. Vacuum liquid chromatography and gel filtration using a Sephadex LH-20 were used to isolate and identify the compounds. Antioxidant assays were carried out using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azinobis (3-ethyl-benzothizoline-6-sulfonic acid (ABTS), and ferric reducing antioxidant power (FRAP) assays, and the scavenging activity was calculated as (IC50
± SEM). The result revealed that in the ABTS assay; the n-butanol soluble fraction (Sample D) exhibited a dose-
dependent scavenging activity with an IC50 of 43.76 ± 2.38 μg/ml followed by the ethyl acetate soluble fraction
(Sample C) with IC50 of 49.90 ± 2.99 μg/ml in comparison to the standard drug ascorbic acid with IC50 of 20.20
± 0.23 μg/ml. In the DPPH assay method, the n-butanol chromatography fraction (Sample E) showed the highest
DPPH scavenging activity with IC50 of 16.53 ± 1.17 μg/ml followed by n-butanol soluble fraction which gave an IC50 of 18.14 ± 0.18 μg/ml which were both higher than the standard drug ascorbic acid with IC50 of 37.42 ± 1.67 μg/ml. In the reducing power assay, the n-butanol soluble fraction (Sample D) showed the highest activity with IC50 of 46.99 ± 2.10 μg/ml while the ethyl acetate fraction gave an IC50 value of 53.37 ± 1.53 μg/ml in comparison to ascorbic acid with an IC50 of 29.18 ± 0.66 μg/ml. Purification of the ethyl acetate and n-butanol fractions afforded 11-O-galloyl Bergenin, Myricetin-3-O-glucoside, and a mixture of bergenin and Methyl Bergenin. The compounds were identified using LC-MS. The presence of these compounds might explain the antioxidant and nutritional potential of this plant.