Physicochemical Properties, Fatty Acids Composition and Antioxidant Potential of the Seed Kernel Oil of Oysternut (Telfairia pedata) Found in Kenya

Aim: Certain edible plant sources contain vegetable oils that have been under-exploited both commercially and in research. This study aimed to determine the physicochemical properties, fatty acids composition, and antioxidant potential of the oil from the seed kernels of Telfairiapedata, which are used as food by the local population of Tharaka-Nithi County in Kenya.

Materials and Methods: Telfairia pedata seeds were collected from farmers in the county of Tharaka-Nithi, Kenya. n-Hexane was used to extract the oil via soxhlet extraction. Standard laboratory protocols were used to characterize the oil’s physicochemical properties, while fatty acids composition and antioxidant potential were characterized using gas chromatography mass spectrometry and 2, 2-diphenyl-1-picrylhydrazyl assay, respectively.

Results: The seed kernels of Telfairia pedata yielded more than 66% of oil. The oil’s physicochemical properties were found to be within the Food and Agriculture Organization set limits and were as follows; moisture content (0.0592±0.0140%), peroxide value (0.9641±0.2021 meq O2/Kg), iodine value (23.0058±2.2473 gI2/100g) and acid value (0.6352±0.0330 mg KOH/g). Fatty acids such as myristic acid (14:0; 0.11%), palmitoleic acid (16:1n7; 0.13%), palmitic acid (16:0; 34.97%), margaric acid (17:0; 0.10%), linoleic acid (18:2n6; 48.46%), stearic acid (18:0; 15.33%), 10,13-octadecadienoic acid (18:2n5; 0.09%), 18-methylnonadecanoic acid (20:0; 0.68%), and behenic acid (22:0; 0.14%) were found in the oil. The antioxidant potential of the oil expressed in IC50 was found to be 18.05 mg/mL, in relation to that of ascorbic acid 2.406 mg/mL.

Conclusions: Telfairia pedata seed kernel oil can be economical to exploit commercially due to its relatively high yield. The determined properties of Telfairiapedata seed kernel oil present high nutritive value making the oil fit for edible applications.