| dc.description.abstract | Sago (Metroxylon sagu) has been one of the important raw materials for the production of useful substances. Because contains more than 80% carbohydrates, which is consists of 55.86% starch and 14.52% lignocellulosic material, the utilization of sago pith is essential for the fermentable sugar production in terms bioenergy production. In other hand, using the sago pith might prevent the waste of the resources. Lignin is one of the main components in lignocellulosic materials in sago pith. Its existence influence the sago pith structural rigidity by holding and stiffening the fibres together so decreasing the enzymatic suspectibility of sago pith. The use of microwave radiation is a promising approach to pretreatment that utilizes thermal and non-thermal effects generated by microwaves in aqueous environments. This study have shown that the microwave heating caused the process of swelling and gelatinization of starch granules and also could enhance lignin degradation itself. Thus could be very efficient in destroying the starch and lignin crystalline arrangement, obtaining a soft gel, and destroying cellulose-hemicellulose structure. On the other hand, if the energy that given to the slurry of sago pith more than it needed then it would build resistant characteristic of sago pith and increasing enzymes concentration wouldn’t enhance yield of reducing sugars. Pretreatment were evaluated based on yields of total sugars, reducing sugars, polymerization degree, equivalent dextrose, filtrate volumes, weight of residue, and filtrate purity from enzymatic hydrolysis of the pretreated biomass. The experimental results in this study can be used in existing simultant process of bioethanol production by using Pichia stipitis and Saaccharomyces elippsoides. The highest ethanol content was given by technical glucose and fermented by Pichia stipitis, prove the pretreatment could not efficiently degradated biomass due to the lignin content was too high. Thus, the lignin content is one of the matter in efficiently pretreatment in order to get the highest yield of reducing sugars. | en |
