The nutrients, natural products and antioxidant capacity of flour from Livingstone potato (Plectranthus esculentus) tubers were investigated. The flour contained 8.26 ± 0.20% moisture, 2.58 ± 0.18% ash, 2.60 ± 0.07% dietary fiber, 5.30 ± 0.17% lipid, 7.87 ± 0.04% protein and 76.00 ± 2.33% carbohydrate, but contained low amount of thiamine, riboflavin and niacin. The total flavonoid content of flour was lower (P < 0.05) than its total phenolic content. The antioxidant assay of flour (determined using 2,2-diphenyl-1-picrylhydrazyl radical and reducing power assays) indicated its strong antioxidant activity, although lower than that of quercetin. Gas chromatographic mass spectrometric assay of methanol/chloroform extract of flour revealed the presence of 13 compounds, whereas the major compounds in the extract with identified biological properties were 9,12-octadecadienoic (55.31%), 12-methyl-E,E-2,13-octadecadien-1-ol (21.68%), 10-octadecenoic acid methyl ester (2.74%) and 3,5-di-t-butyl phenol (2.34%). Livingstone potato contains strong antioxidant activity and some bioactive compounds that support its biological properties. Practical Applications This paper reveals the bioactive principles/natural products in Livingstone potato that justify its biological properties as used in folklore medicine. By isolating and identifying some compounds with biological activities in this plant, new drugs could be developed from this plant in the future to treat various diseases.
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