**2.8. Ethanol determination**

The ethanol content in fermented solution was analyzed by gas chromatography (GC). GC analysis was carried out with an Agilent Technologies (Santa clara, CA) 6890 gas chromato‐ graph equipped with a flame ionization detector and a HP-5 (Bonded 5%phenyl, 95% dime‐ thylpolysiloxane) capillary column (30 m x 0.32 mm ID, 0.25 µm film thickness). The temperature program was an initial temperature of 150ºC, increased to 190ºC at 10ºC/min then 15ºC/min to 250ºC, and held for 15 min. The injector and detector temperature were 250 ºC and 300ºC, respectively. Standard and sample were injected by using the split mode ratio of 50:1.
