A 5 g of sample was
extracted with a solvent mixture containing 40 ml acetone and
60 ml hexane until the residue became colourless. The
homogenate was filtered through Whatman No. 4 filter paper
and transferred to a separating funnel. Fifty millilitres of
hexane was added, and acetone was separated from the
extract by repeated washings with distilled water and 5% NaCl
solution. The upper hexane layer with extracted pigment was
shifted to a 100 ml volumetric flask, and the volume is made
up with hexane. The absorbance was measured using
spectrophotometer (Shimadzu 1609, Tokyo, Japan) at 450 nm
with hexane as blank. The total carotenoids were calculated
using the following formula