Table 2. Operating condition for GC analysis

Equipment	Gas chromatograph (GC-17A, SHIMADZU Co., Japan)
Column	Capillary column (CBP-1-M25-O25) 25 m × 0.22 mm × 0.25 μm
Carrier gas	Nitrogen, constant flow
Oven temp.	70°C (1 min) → 200°C (30 min, 20°C/min) → 280°C (10 min, 1°C/min)
Injector temp.	250°C
Detector (FID) temp.	260°C