Abstract Natural and biosynthesized phytocompounds have gained significant attention in the food industry because of their non-controversial health and safety benefits as compared with chemically synthesized antioxidants. However, no natural biosynthesized phyto-compounds has been commercially available and used in routine food processing. This study evaluates the antioxidant property of Sidaacuta plant commonly used by many locals in storing cooking oils. The ethanolic leaf extract of this plant was evaluated for its antioxidant potential, total phenolic (TP) and total flavonoid (TF) contents using standard procedures. The extract was added to groundnut oil at four different concentrations of 100 mg/L, 200 mg/L, 400 mg/L and 800 mg/L and stored over a six-month period, while chemical properties of oil including peroxide value (PV), anisidine value (AnV), acid value (AV) and iodine value (IV) were checked on a monthly basis. The results showed that the extract had significant antioxidant effect for DPPH radical scavenging activity (27.4800±0.0173 IC50 % inhibition), β-carotene linoleic antioxidant activity (29.7267±0.0251 IC50 % inhibition), ORAC (6.1067±0.0115 µ Mol TE/g) and FRAP (291.0367±0.0305 µ Mol Fe2+/L). Total phenolic content expressed in tannic acid equivalents was 27102.365±10.189 µg/ml, while total flavanoid content expressed in quercetine equivalents was 1024.783±5.569 µg/ml. The addition of the leaf extract to oils showed significant retardation of oxidation compared to samples without the extract. The findings reveal that the use of Sidaacuta as a natural antioxidant to prevent vegetable oils oxidation if properly harnessed can be a good alternative to synthetic antioxidants.
Keywords Lipid peroxidation, groundnut oil, natural antioxidant, chemical property.