Haji Khamis, Kituyi Lusweti, Haji Mwevura, Steven Nyanzi, B.T. Kiremire, Tanzania
Tomatoes (Solanum lycopersicum) and red-fleshed watermelons (Citrullus lanatus) contain lycopene, which have many important health benefits. However, no study has so far been done to establish the degree of purity of lycopene in fresh tomatoes and watermelons in Uganda, and East Africa in general. The objective of this study was to separate and purify lycopene in selected tomato and watermelon varieties in Uganda and then determine its % purity. The varieties were bought from Nakulabye market in Kampala, and extracted by using solvent system of hexane/acetone/ethyl acetate (4:2:1 v/v/v). The extracts were filtered and the lycopene layer (extracts) were then separated from the filtrate by using separating funnel, washed, dried by rotary evaporator and then dissolved in hexane. The concentrated hexane solution was then fractionated by using the alumina column chromatography. The purity of lycopene was determined by using high performance liquid chromatography (HPLC). The % purity of lycopene was calculated by dividing the area of lycopene peak to the total area of peaks from the HPLC chromatogram. The results obtained showed that the quantity of lycopene varied from 140 ?g/g to 791 ?g/g wet weight in tomato and for watermelon was 326 ?g/g. The % purity ranged from 76.3% to 87.8% for tomato varieties. The chromatograms of lycopene from watermelon did not appear properly. Purity products are committed to providing customers with evidence based nutrition's supplements. The % purity of extracted lycopene may be increased by crystallization of lycopene.