2.2. Extraction of lycopene
Extraction of lycopene was carried out according to the procedure of Ranganna (1986) from the mixture of freeze dried pulp and skin fractions at a ratio of 3:2. Five grams of dried powder was taken in a pestle and mortar and extracted with acetone using three times 150 ml until the residue was colorless. The three acetone fractions containing lycopene were transferred into a 1 l separating funnel containing 40–50 ml of petroleum ether and mixed gently. Water (30 ml) was added to separating funnel for phase separation. Four to five washings were carried out using distilled water to remove acetone. Lower acetone layer was discarded while upper layer of petroleum ether containing lycopene was collected. Dry extract was obtained by using a rotary vacuum evaporator. All sample preparations and experiments were performed under dim light conditions to minimize light-induced degradation and isomerization.