1 g dry ground corn straw powder was poured into a
118-mL serum glass bottle, after which 10 mL distilled water was
added into the bottle. After autoclaving for 120 min at 121C
(SANYOMLS-3020, SANYO Electric Co., Ltd, Japan), the bottles were
inoculated with the complex microbial agents in aseptic conditions. A 0.01% (w/w) dose of the complex microbial agents was
used in our study. Each of 20 bottles was then covered and sealed
with a plastic film. A sponge plug was inserted into the middle of
the film to sparge air while preventing airborne microorganisms
from entering the bottle. The control bottle was not inoculated
with complex microbial agents. It only contained 1 g dry ground
corn straw and 10 mL distilled water. The bottles were placed in
an incubation chamber. Samples were obtained on the 0th, 5th,
10th, 15th, and 20th day of incubation for composition determination, chemical analyses, and biochemical methane potential (BMP)
assay.