EFFECTS OF BOILING ON THE ANTIOXIDANT PROPERTIES OF THREE SPECIES OF GARDEN EGG (Solanumaithiopicum Solanumaubergine and Solanumanguivi)

Abstract

Garden egg (Solanum spp) has been reported to exhibit several pharmacological properties and widely used in folk medicine for the traditional treatment of ailments. Hence, this study sought to investigate the antioxidant properties of the aqueous extract of boiled and unboiled garden egg varieties (solanumaubergineSolanumaithiopicumSolanumanguivi) using several antioxidant parameters. The extract were tested for free radical scavenging ability, ferric reducing properties and Fe 2+ chelating ability. Furthermore the phytochemicals constituent (Total phenolic, flavonoids and vitamin C) of the extract were determine. Result showed that the extracts demonstrated potent free radical scavenging and ferric reducing ability and iron chelating activity in vitro. The total phenolic content, and the antioxidant capacity (free radical scavenging ability, ferricreducing properties and Fechelating ability), of the boiled extracts were substantially higher than those of the unboiled, while the flavonoid, vitamin C and Fe2+ chelating ability of aqueous extract of Solanum spp of the boiled extract reduced for all the three varieties studied. Among the three varieties, solanum aubergine has a significantly much higher content of total phenolic which varied between (11.87-18.75mg gallic acid equivalents [GAE] mg/ml). Additionally, a high correlation between total phenolic content and antioxidant capacity (except Fe 2+ chelating ability of aqueous extract which reduced) was found in all the three garden egg varieties. In conclusion, our results demonstrated that the effectiveness of bioactive compounds in food can be affected by thermal treatment. Boiling can increase the antioxidant activity.