초록
<P><B>Abstract</B></P> <P>Macroalgae are increasingly regarded as a potential feedstock for sustainable biobutanol production. However, macroalgae cell-wall polysaccharides must be properly pretreated for subsequent efficient enzymatic hydrolysis to fermentable sugar. The effects of different chemicals (H<SUB>2</SUB>SO<SUB>4</SUB> and NaOH), chemical concentrations (1–9% (w v<SUP>−1</SUP>) H<SUB>2</SUB>SO<SUB>4</SUB>), pretreatment temperatures (95 °C and 121 °C), and times (30 and 60 min) with <I>Rhizoclonium</I> spp. on the efficiency of the subsequent hydrolysis were studied. The results showed that the highest sugar released in the hydrolysate of 558 mg sugar per g algae was obtained from algae pretreated with 3% H<SUB>2</SUB>SO<SUB>4</SUB> at 95 °C for 1 h. Acetone, butanol ethanol fermentation by <I>Clostridium beijerinckii</I> TISTR 1461 was carried out with low external supplementation resulting in a yield of 135 mg butanol per g sugar equal to 49 mg butanol per g algae. This work showed the feasibility of converting residual aquatic biomass of <I>Rhizoclonium</I> spp. into sugar rich solutions for enzymatic fermentation.</P> <P><B>Highlights</B></P> <P> <UL> <LI> First report on pretreatment of <I>Rhizoclonium</I> spp. for ABE fermentation. </LI> <LI> The highest sugar yield obtained when pretreated with 3% H<SUB>2</SUB>SO<SUB>4</SUB> at 95 °C for 1 h. </LI> <LI> Maximum 558 mg reducing sugar per g algae was obtained. </LI> <LI> ABE could be produced from <I>Rhizoclonium</I> spp. with low external nutrient added. </LI> <LI> Residual macroalgae of <I>Rhizoclonium</I> spp. is a potential biofuel producer. </LI> </UL> </P>