The total carotenoid (TC) content was determined as reported by
Bono et al. (2012) with slight modifications. Briefly, 1 g of the dried material
was homogenized for 30 s at full speed with 20 ml of acetone using
a vortex (Heidolph REAX 2000, Germany). 10 ml of petroleum ether (BP
40–60 °C) was added to the acetone extract and then vortexed for 30 s.
Ten milliliters of 0.1% NaCl was added to the acetone/petroleum ether
mixture and then vortexed for 30 s. After centrifugation of the homogenate
(6000 rpm for 10 min), the supernatant was removed and then
evaporated under vacuum at room temperature using a Speedvac
(SC210A, Savant Instruments, Farmingdale, NY).