Production of bioethanol from sago hampas via Simultaneous Saccharification and Fermentation (SSF)

Abstract

Huang CH, Adeni DSA, Johnny Q, Vincent M. 2018. Production of bioethanol from sago hampas via Simultaneous Saccharification and Fermentation (SSF). Nusantara Bioscience 10: 240-245. Sago hampas is an inexpensive, renewable and abundant agro-industrial residue that can be exploited to produce bioethanol. In this study, ethanol production was performed via simultaneous saccharification and fermentation (SSF) on fresh sago hampas at 2.5%, 5.0% and 7.5% (w/v) feedstock loadings with the aid of amylolytic enzymes, cellulolytic enzymes and Saccharomyces cerevisiae, under anaerobic condition for five days with a constant agitation of 150 rpm and ambient temperature. Results obtained indicated that SSF with 5.0% (w/v) sago hampas loading produced the highest ethanol yield at 17.79 g/L (79.65% Theoretical Ethanol Yield, TEY), while SSF using 2.5% and 7.5% (w/v) sago hampas produced ethanol at only 8.38 g/L (75.00% TEY) and 23.28 g/L (69.48% TEY), respectively. Total biomass reduction was recorded between 66.3% to 71.3% by the end of the SSF period. This study demonstrated that fresh sago hampas is a promising feedstock for bioethanol production as yields are generally high for all the substrate loadings tested. Moreover, bioethanol production using fresh sago hampas may assist in reducing pollution caused by sago waste accumulation.

Potential of Candida glabrata from ragi as a bioethanol producer using selected carbohydrate substrates

“…As outlined in Table 2, dried sago hampas used in this study contained 52.03% starch, 27.82% cellulose, 5.32% hemicellulose and 3% lignin. The results obtained in this work are comparable to a previous report by Hung et al (2018), where sago hampas were reported to contain 55.4% starch, 23.6% cellulose, 9.1% hemicellulose, and 4.0% lignin. Furthermore, the starch content recorded in this study, which was in the range of 30% -50% was comparable with that reported by Awg-Adeni et al (2010).…”

“…Based on Figure 6, a steep decrease of total sugar content during the first 6 h indicated that the substrates present in the fermentation broth were rapidly fermented into ethanol by C. glabrata. The same observations were also reported by Hung et al (2018) who stated that not all sugars can be converted to ethanol. In addition, the results obtained in this study showed the presence of other unknown hexose sugars in the fermentation broth besides glucose.…”

“…After the depletion of glucose at 6 h, the ethanol concentration continued to increase until its maximum production at 24 h. The highest ethanol concentration was 5.44 g/L. This corresponds to an estimated 21.25% TEY, which is significantly lower than that reported by Hung et al (2018) (79.65% TEY). The author reported a higher TEY because they used only sago hampas as substrate, while in this study, the mixture of sago effluent and sago hampas was used.…”

“…TSE consists of sago hydrolysate, which is the liquid part while the solid component is called sago hampas. It is reported to contain high amount of lignocellulosic materials, which can be found in the solid sago hampas, making it suitable to be used as a substrate for bioethanol production (Hung et al 2018). The hydrolysate can also contribute to bioethanol production as it contains starch that can be converted into fermentable sugars (Vincent et al 2015).…”

Development of Rhodotorula mucilaginosa strain via random mutagenesis for improved lipid production

“…The limited petroleum reserves and serious environmental pollutions have triggered the necessity to exploit alternative renewable energy sources, such as bioethanol and biodiesel (Huang et al, 2018). Biodiesel is an outstanding renewable fuel that can supplement petroleum fuel .…”