P2 Exploring the functional components of the African horned cucumber (Cucumis metuliferus), Mokapana (Tswana) – Characterisation by phenolic content and antioxidant activity in Botswana

Abstract

The African horned cucumber (Cucumis metuliferus) is a traditional food plant indigenous to Southern Africa. It grows naturally and is commonly found in Botswana, Namibia, South Africa and Swaziland. In Botswana it is found throughout the country. The fruit is mostly consumed fresh, pressed into juices, eaten like an ordinary cucumber, or used in fruit salad. Cucumis metuliferus has become one of the most popular fruits with a potential to be fully commercialised. The fruit is covered with prominent spines and is about 10 cm in length. It turns yellow-orange when ripe. In Botswana, there is a rich variety of wild fruit plants which have served as mainstay sources of nutrition and medicines for many years (Motlhanka et al., 2008). Like vegetables, wild fruits are excellent sources of minerals and vitamins, which are essential for proper maintenance of good health. However, these wild fruits have not received much attention as sources of antioxidants compared to their commercial counterparts. Duthie and Crozier (2000) reported phenolic compounds to account for most of the antioxidant activity in plants. Recently, natural antioxidants have gained increasing attention from nutritionists and medical researchers for their potential effects in the prevention of chronic and degenerative diseases such as cancer, coronary heart disease, strokes, and aging (Ames et al., 1993; Azam et al., 2004; Diaz et al., 1997; Young & Woodside, 2001).