CC BY-NC-ND 4.0 · Planta Medica International Open 2020; 07(04): e170-e178
DOI: 10.1055/a-1323-0786
Original Papers

Hypolipidemic Activity of Tetracarpidium conophorum (African walnut) Seed Oil and Its Mechanism of Action

Kelly Oriakhi
1   Department of Medical Biochemistry, School of Basic Medical Sciences, University of Benin, Benin City, Nigeria
Patrick Uadia
2   Department of Biochemistry, Faculty of Life Sciences, University of Benin, Benin City, Nigeria
› Author Affiliations
Funding The research was funded by the Tertiary Trust Fund, the University of Benin, Benin City, Nigeria to Oriakhi Kelly, Department of Medical Biochemistry, University of Benin, and the ICCBS-TWAS Postgraduate Fellowship award (FR No. 3240280482). The authors also strongly thank the Natural Product Research and Disease Control Laboratory (NPRDC), Department of Biochemistry, University of Benin for providing the facilities needed to carry out this study.


The present study was designed to evaluate the hypolipidemic activity of Tetracarpidium conophorum oil and its mechanism(s) of action. The oil was extracted using the Soxhlet method and subjected to column chromatography/spectroscopic techniques. GC-MS analysis was performed on the oil to identify 15 constituents with 9,12,15-octadecatrienoic acid (ω-3 fatty acid or α-linolenic acid) (68%) showing the highest proportion. Isolation and purification of the oil gave three compounds, namely, β-sitosterol, stigmasterol, and stearic acid (octadecanoic acid). Thirty-five rats were used and divided into seven groups for the in vivo hypolipidemic study. Findings from this study showed significant decreases (p<0.05) in total cholesterol, triglycerides, and low-density lipoprotein cholesterol, and an increase in high-density lipoprotein cholesterol in rats fed a normal diet and receiving T. conophorum oil (250 and 500 mg/kg body weight) for 20 days. But there were significant increases (p<0.05) in total cholesterol, triglycerides, low-density lipoprotein cholesterol, creatine kinase, lactate dehydrogenase, aspartate amino transferase, malondialdehyde, 3-hydroxy-3-methylglutaryl-coenzyme A reductase, and C-reactive protein levels with a decline in the low-density lipoprotein cholesterol level in rats fed the high cholesterol diet when compared to those fed a normal diet. However, oral administration of T. conophorum oil and atorvastatin for 20 days resulted in a significant lowering (p<0.05) of triglycerides, low-density lipoprotein cholesterol, creatine kinase, lactate dehydrogenase, aspartate amino transferase, malondialdehyde, 3-hydroxy-3-methylglutaryl-coenzyme A reductase, and C-reactive protein levels with a rise in high-density lipoprotein cholesterol in rats nourished with the high cholesterol diet. The study showed that T. conophorum seed oil possesses hypolipidemic and cardioprotective properties.

Supplementary Material

Publication History

Received: 12 May 2020
Received: 16 November 2020

Accepted: 24 November 2020

Article published online:
19 January 2021

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