Screening South African potato, tomato and wheat cultivars for five carotenoids

Abstract

In South Africa malnutrition is of great concern. Vitamin A deficiency is one of the leading causes of infections as a result of micronutrient malnutrition. Although supplementation and food fortification programmes exist, these either are not available or are unaffordable to communities in remote rural areas. The selection of crops that are naturally rich in provitamin A (β-carotene) and other carotenoids that can be recommended to small-scale farmers for breeding and for food production, could be an effective way to address vitamin A deficiencies and associated diseases. The aim of this study was to profile two cultivars each of potato, tomato, bread wheat and durum wheat, which are highly consumed crops in South Africa, for their carotenoid content using high-performance liquid chromatography. To this effect, reliable extraction and quantification of five carotenoids - lutein, zeaxanthin, canthaxanthin, β-carotene and lycopene - were performed for these crops. Lutein and zeaxanthin were found to be the major carotenoids in potato, whilst lycopene was the major carotenoid in tomato. In durum wheat, only lutein and zeaxanthin were identified whilst bread wheat contained lutein, zeaxanthin and β-carotene. The methodology used proved to be robust and suitable to screen a large number of potato, tomato and wheat cultivars for their carotenoid content.