초록
<P><B>Highlights</B></P><P>► We developed the complete enzymatic saccharification process for agarose. ► The process is divided into chemical liquefaction and enzymatic saccharification. ► Acectic acid was used as an acid catalyst in the chemcial liquefaction. ► Multiple agarases and a hydrolase were employed in the enzymatic process. ► The process was evaluated by the SSF of agarose for bioethanol production.</P> <P><B>Abstract</B></P><P>A sugar platform equipped with acetic acid, multiple agarases and neoagarobiose hydrolase (NABH) converted recalcitrant agar polysaccharide into monosugars, which was evaluated by simultaneous saccharification and fermentation (SSF). The sugar platform was divided into chemical liquefaction and enzymatic saccharification. The chemical liquefaction was carried out in mild conditions (using a dilute acetic acid at 80°C for 1–6h) to avoid the production of fermentation inhibitors and hence the highest degree of liquefaction of 95.6% (w/w) was obtained. We mimicked the natural agarolytic pathway using three microbial agarases (Aga16B, Aga50D and DagA) and NABH, and the enzyme system converted 79.1% of agarose to monosugars. The chemical liquefaction and SSF of 30g/l agarose resulted in 4.4g/l ethanol concentration and 49.3% of the theoretical ethanol yield to <SMALL>D</SMALL>-galactose. This is the first report on the complete enzymatic conversion of agarose into its monosugars and the SSF of agarose into ethanol.</P>