2.3. Extraction
Soxhlet extraction was carried out as follows: pitaya seed kernels
(3 g) were extracted with 150 ml hexane for 3 h at 60 C,
and the solvent was evaporated and recycled. MAE was performed
in a modified household microwave oven (Gelanshi 800DSE30, China).
Pitaya seeds kernels (3 g) was mixed with 25 ml hexane and
the mixture was placed in a flat bottom flask (150 ml), which
was connected to a condensor at the top to ensure solvent reflux.
The flask was put into the microwave oven for different time at
2.45 GHz. The solvent was evaporated and recycled.