2.2. Pretreatment of MG
MG was pretreated using the grass optimization method according
to Boonmanumsin et al. and Tatijarern et al. The milled grass
was mixed with 3% w/v NaOH using a liquid-to-solid ratio (LSR)
of 15 mL of NaOH: 1 g of grass (Boonmanumsin et al., 2012;
Tatijarern et al., 2013). The mixture was stirred thoroughly until
it was homogenous. Then, it was subjected to microwave treatment
(300 W, Ethos Series, Milestone Inc.) at 120 C for 10 min. After the
alkaline pretreatment, the mixture was washed until the pH was
neutral. The solid residue was oven-dried for 24 h. The dry solid
was stored in a dry container at room temperature.