ABSTRACT
Vegetables possess both nutritional and medicinal properties and are daily consumed as food in form of beverages or health supplement. The aim of this study is to compare the medicinal and food values of two vegetables (Corchorus olitorius andTelfairia occidentalis). The following parameters were determined, these are; proximate, minerals, antioxidants, and phytochemicals (secondary metabolites) compositions. Results revealed that ash, fat and carbohydrate contents were higher in Corchorus olitorius (21.67%, 12.67% and 46.93% respectively). Telfairia occidentalis contained higher amounts of moisture and crude fibre contents (11.89% and 4.55% respectively). The mineral analysis showed that potassium had the highest value (1715.69mg/100g), sodium (49.62mg/100g), calcium (33.43mg/100g), iron (16.78mg/100g), manganese (9.44mg/100g), magnesium (4.39mg/100g), zinc (2.94mg/100g), copper (2.11mg/100g) and lead had the least value (0.21mg/100g). The antioxidant activity revealed that standard ascorbic acid had higher antioxidant activity values for TAC, reducing power, hydrogen peroxide and DPPH, where p <0.05. There was no significant difference between reducing power of Telfairia occidentalis and Corchorus olitorius where p<0.05. The DPPH scavenging activity was significantly higher in Telfairia occidentalis compared to Corchorus olitorius where p <0.05. Hydrogen peroxide scavenging activity was significantly higher in Corchorus olitorius as compared toTelfairia occidentalis where p<0.05. There was no significant difference between the total antioxidant capacity of Telfairia occidentalis and Corchorus olitorius where p<0.05.The qualitative phytochemical screening revealed the presence flavonoids, phenols, saponins, tannins, steroids and alkaloids in both extracts; terpenoids was only present in and Telfairia occidentalis, while cardiac glycosides was present only in Corchorus olitorius,quinones was not detected in plant both extracts.High performance liquid chromatography of methanol leaf extract of Corchorus olitorius revealed that quercitrin, quercetin,catechin,epicatechin, kaempferol and sinapinic acid were present in higher amounts. Plants containing phenolic and flavonoid class of compounds are reported to possess excellent antioxidant activity.
