2.3. Soxhlet extraction (SE) process
Rice
bran was placed into a cellulose paper cone and extracted for 6 h in a
Soxhlet extractor at 90 ℃ with n-hexane
according
to the Soxhlet standard extraction method (AOAC,
1997).
The oil was then recovered by evaporating off the solvent at 50 ℃ under
reduced pressure
using
a rotary evaporator Model RE-2000A
(Yarong
Biochemical Instrument Factory, Shanghai, China) and residual solvent
was removed by flushing with 99.99% nitrogen. This technique produced
18.45 ± 0.25 g of oil per 100 g of rice bran, which was set as 100% oil
recovery for comparison. The recovered oil was stored at 4 ℃ until use.