GC–FID system is consisted of an Agilent Technologies 7890B Series gas chromatograph system with a flame ionization detector (FID) equipped with an 7693A automated sample injection system (Agilent Technologies, Wilmington, Delaware, USA). ChemStation software is used for system operation, data acquisition and processing. The FID is sensitive detector, capable to detect compounds that contain carbon atoms (C), which accounts for almost all organic compounds.