Refined sunflower oil (100 g) was mixed with 10 g of acti-vated carbon in a 250 mL glass bottle and capped after flushing with nitrogen. The mixture was stirred overnight at room temper-ature (23 ± 2C) in an orbital shaker at 50 rpm, and then centri-fuged for 10 min at 10,000 rpm (Sigma 3–18 K, Sartorius AG, Göttingen, Germany). The oil phase was decanted and diluted with
200 ml of n-hexane and passed through a chromatographic column
containing activated alumina, which was prepared by holding the
alumina at 100C (16 h) prior to heating at 220C for 6 h. Acti-vated alumina (150 g) was mixed with 250 ml n-hexane to pro-duce a slurry that was transferred to a glass chromatography
column (30028 mm i.d.). After passing 150 ml of puren-hexane
through the column, the diluted oil was loaded into the column.
The sample was washed with 150 ml of n-hexane. The solvent
was evaporated using a rotary evaporator under reduced pressure
at 40C to obtain the stripped oil.