Quantification of Lycopene from Tomatoes and Watermelons by Using Beer-Lambert Principle

Red tomatoes and red-fleshed watermelons contain a high level of lycopene. It is well known that lycopene is precursor to vitamin A. In Uganda, and East Africa in general, there are so many tomato and watermelon varieties with little information on their lycopene content. However, no study has been done to estimate the quantity of lycopene in fresh tomatoes and watermelons in Uganda. The objective of this study was to quantify lycopene by using Beer-Lambert Principle. The varieties were bought from Nakulabye market in Kampala, and extracted by using solvent system of acetone/ethanol/ hexane (5ml/5ml/10ml). Stirring on ice was done for 15 minutes. 3 ml of deionized water was added after shaking. Samples were shaken for 5 minutes on ice and then left at room temperature for 5 minutes to allow the separation of phases. The lycopene layer were then separated and scanned in UV-VIS spectrophotometer. The results showed that the lycopene concentration ranged from 27 ?g/g to 115 ?g/g with % relative error ranged from 2.86 to 3.14, the standard error ranged from ± 0.013to ± 0.015,and standard deviation ranged from 7.38 to 29.5. Both watermelons and tomato varieties contain the appreciable quantities of lycopene which is the significant nutrient for human body in daily life.