ANTIOXIDANT ACTIVITIES OF GUAVA FRUITS
Fruit extracts for carotenoid analysis were prepared
following the method of Wilberg and BodriguezAmaya
(1995), with some modifications. Three grams
of guava tissue (flesh and peel) was mixed with 20 ml
of ethanol-hexane (1:1) solution that contained 200 mg/
l 2,6-di-ter-butyl-p-cresol to avoid carotenoid oxidation
and then homogenized using the Ultra-Turrax
homogenizer until there was uniform consistency. The
homogenate was filtered using a Whatman No 4 and
re-extracted three times with 20 ml of solvent. The
extract was washed tree times with nanopure water.
The supernatant was recovered and added with hexane
to a final volume of 10 ml; then stored at -20°C until
assayed.