Antioxidant potential of the farmer preferred selections of Solanum aethiopicum vegetable consumed in central Uganda

Abstract

In addition to the rich micronutrient value, indigenous vegetables are regarded as possessing medicinal attributes. The Solanaceae family has over 1000 species worldwide, with a number of indigenous species originating in Africa. The most popular leafy vegetable in Uganda is the Solanum aethiopicum (Nakati). The objective of this study was to determine the selected phytochemical attributes, chlorophyll content, moisture content and total antioxidant activity of the farmer preferred selections within the landraces of Solanum aethiopicum leafy vegetable in Uganda. The antioxidant activity was achieved by screening the leaf extracts for their free radical scavenging properties using diphenyl picryl hydrazyl (DPPH) and ascorbic acid as standard. The ability of the extracts to scavenge DPPH radical was determined spectrophometrically at 517nm.The study showed that all the landraces had a high polyphenol and flavonoid content with SAS185/P/2015 containing the highest flavonoid content (3.16±0.06 mg QE/g fw). SAS1641/2015 showed the highest total polyphenol content of 7.79±0.27 mg GAE/g fw and also showed the highest vitamin C content. This contributed to the high total antioxidant activity of 2.79±0.01 and 5.43±0.02 mg AAE/g fw when using FRAP and DPPH methods respectively. SAS145/2015 presented the highest chlorophyll content of 19.69±0.01 mg/g dwb. All the landraces showed a high percentage moisture content that ranged from 82.66±0.35 to 84.21±0.48%. These results are of nutraceutical significance and hence confirm their usage as medicinal vegetables. DOI: http://dx.doi.org/10.5281/zenodo.1195552

Keywords

• Landraces
• Polyphenols
• Flavonoids
• Vitamin C
• Total antioxidant activity
• Ferric reducing antioxidant power (FRAP)