sentence: Upon reconstitution in 315 μ L tetrahydrofuran : n-hexane ( 4:1 ) , the extracts were fractionated by high-performance liquid chromatography ( HPLC ) on an Alliance 2695 separation module ( Waters ) equipped with a normal-phase Spherisorb Si60 analytical column ( 250 × 4.6mm ID , 5 μ m ; Waters ) .