Residual crude oil after extraction (as described in the gravimetric analysis section) at
the end of each incubation period was quantified chromatographically
via capillary gas chromatography (CGC) using
Agilent 6890 plus gas chromatograph equipped with flame
ionization detector (FID), split/splitless injector, and fused
silica capillary column HP-1 of 30mlength, 0.35mminternal
diameter, and 0.5