In Vivo Bioavailability of Lycopene from Watermelon (Citrullus lanatus Thunb) Coloring.

Diet containing watermelon coloring (5, 20, 35 and 50 mg lycopene/100g) was fed to albino rats to study in-vivo bioavailability of lycopene. The rats were fed with lycopene enriched test diets for seven days of treatment period along with control diet during pre and post treatment periods of seven days each. The body weight of each group of albino rats significantly increased during feeding trial which showed that rats were in healthy condition during the treatment. The daily lycopene intake from test diets varied from 0.03 to 0.51 mg during treatment period of seven days which decreased to 0.02-0.07 mg during post-treatment period with control diet. The lycopene absorbed by different groups of rats varied from 0.22 to 3.74 mg/kg body weight of rat during treatment period and 0.15-0.67 mg/kg body weight of rat during post-treatment periods. Lycopene bioavailability increased proportionately with the lycopene content of test diet.

Utilization of watermelon pulp for lycopene extraction by response surface methodology.

Lycopene extraction was optimized from watermelon pulp using response surface methodology using independent variables:solvent/meal ratio (4:1-12:1v/w), number of extractions (1-5), temperature (20-60°C) and extraction time (4-20min). Watermelon pulp had 59.95mglycopene/100g on fresh weight basis. The experimental values of lycopene with selected combinations of independent variables were 8.20-59.17mg/100g on fresh weight basis. The second order model obtained revealed a coefficient of determination (R2) of 0.986, the standard error of 0.04, the root mean square error of 0.02 and a scattered plot between experimental and predicted values. The optimum solvent/meal ratio, number of extractions, temperature and extraction time were 10:1v/w, four, 50°C and 16min respectively. The optimum conditions of lycopene extraction were confirmed experimentally.