Fatty acids and chlorogenic acid content in Plectranthus edulis root tubers

Abstract

This study quantified the fatty acid profile and total chlorogenic acid content of various Ethiopian cultivars of the Plectranthus edulis tuber, traditionally known as 'Agew Dinich'. Lipid extraction utilized the Folch method and the acid-catalyzed derivatization method to derivatize the fatty acids into fatty acid methyl ester (FAME) were used. Whereas maceration was used to extract chlorogenic acid from the fresh and freeze- dried tuber samples. Analysis revealed a total of thirteen fatty acids in all P. edulis samples, with nine classified as saturated and four as unsaturated. Palmitic acid was the most abundant fatty acid in P. edulis and accounted for 40.57%-50.21% of the total fatty acid content. The second and third most abundant fatty acids in the P. edulis sample were stearic and linoleic acids, which accounted for 8.38%-12.92% and 8.12%-11.28%, respectively. We reported chlorogenic acid for the first time in this potato species and found it to contain a concentration of 211± 4.2-300±24.7 mg/100g of dry weight basis when the determination was made using fresh samples. On the other hand, these samples yielded a chlorogenic acid concentration ranging from 115 ±8.6 mg/100g-175±3.9 mg/100g of freeze-dried powder samples. These findings suggest that P. edulis tubers could represent a significant dietary source of both chlorogenic acid and fatty acids.