BIOETHANOL PRODUCTION
FROM SEVERAL TROPICAL WOOD SPECIES USING SIMULTANEOUS SACCHARIFICATION AND
FERMENTATION PROCESSES
Muhammad Daud1, Wasrin Syafii2, Khaswar Syamsu3
1Faculty of Forestry, Hasanuddin University
2Faculty of Forestry, IPB
3Agricultural Industry Technology Department, IPB
ABSTRACT
The study was conducted
to determine the best method to hydrolyse (saccharification) and fermentation
in bioethanol production using simultaneous
saccharification and fermentation processes. Three different tropical wood species namely
gmelina wood (Gmelina sp.), pine
wood (Pinus merkusii) and oil palm (Elaeis
guineensis Jacq.) were pretreated using kraft process and then were
produced to bioethanol using simultaneous saccharification and fermentation
(SSF) processes. Pulp were produced
from kraft process were analize to determine their chemical properties
before treatments. SSF runs were performed in 500 ml fermentors using a total slurry 200 ml. The substrate and
nutrient media were autoclaved (121 oC and 20 minutes). The samples
diluted to 2,5% (w/v) of total slurry was used as substrate. The enzyme
preparation used commercial cellulase enzyme. The amount of cellulase added
were 8% and 4% (w/w) dry mass of samples. All SSF processes were inoculated with
10% (v/v) yeast Saccharomyces cereviciae (1.5 x 109 CFU/cc). The SSF experiments
were run for 96 hours, and the data were investigated periodically every 24
hours. The results showed total of sugar and reducing sugar tended to decrease
with time of inoculation whereas ethanol concentration increase significantly.
The growth of yeast Saccharomyces cereviciae tended to incease in initial
inoculation and decrease by the end of inoculation. The best method to
hydrolyse (saccharification) and fermentation on SSF processes for all tropical
wood species were using cellulase 8% of dry mass (DM) and 10% (v/v) of Saccharomyces cereviciae which
produced highest bioethanol concentration gmelina, pine and oil palm were
0.98%; 0.57% and 0.51% respectively and produced yields 11.21%, 5.85% and
3.20%, respectively.
Key words: Bioethanol, simultaneous saccharification and
fermentation, tropical wood species,
cellulase, Saccharomyces cereviciae
