the run was isocratic at a flow rate of 1.5 mL/min. Carotenoids were
detected by UV-Vis (UV detector, Varian 9050) at 460 nm. Linearity
of the variation of peak area as a function of concentration was assessed from triplicate injections of standard solutions (n = 9) over
a concentration range of 1 to 15 mg/L. The correlation coefficient
was 0.9989. This allows the use of only 1 external standard solution
for routine analysis. The concentration of total carotenoids (α and
β carotenes) was expressed as milligram per 100 g of fresh weight.
Carotenoid standards were obtained from Sigma-Aldrich (St. Louis,
Mo., U.S.A.)