Conclusion Day 3 of fermentation showed the highest yield of ethanol at 4.71%. Meanwhile, 20g of glucose would be the optimized glucose as it gained the highest yield of ethanol at 3.94%. On the other hand, the highest yield of ethanol at 6.21% is proven by 3g of yeast. Lastly, pH range between 4.0 and 4.6 achieved the highest yield of ethanol at 1.87%. So, conversion of cellulose from Leucaena leucocephala seeds to bioethanol could be optimized following these parameters; 3 days of fermentation, 20g of cellulose from Leucaena leucocephala seeds, 3g yeast and pH range between 4.0 and 4.6. In conclusion, Leucaena leucocephala seeds would be potentially replace edible plants in production of ethanol.

Bioethanol Production from Leucaena leucocephala Seeds

Atik Zufar bin Haji Mohd Razaki1 and Zul Ilham Zulkiflee Lubes2

1Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia

IntroductionRenewable fuel such as bioethanol could be produced from sugary plants such as sugar cane (Sarkar et al., 2012). However, utilization of sugar cane (Pimentel, 2003) and other edible plants for bioethanol production could lead to the food vs. fuel dilemma as the feedstock is crucial for human needs as well as animal feed. Hence, the high demand for the bioethanol could be unsustainable (Hahn-Hägerdal et. al., 2006). The alternative way is by using the non-edible plants such as the fast growing Leucaena leucocephala. However, there is limited information on the bioconversion of monosugars from the seed of Leucaena leucocephala into bioethanol. This study is conducted to determine the optimum parameters for the fermentation of anhydrous glucose with yeast, convert cellulose from Leucaena leucocephala seeds to bioethanol using optimized conditions, detect the presence of bioethanol from Leucaena leucocephala seeds by using GCMS headspace and calculate the percentage yield of bioethanol. Optimization of the parameters is important to produce high yield bioethanol from cellulose obtained from Leucaena leucocephala seeds.

References:Hahn-Hägerdal, B., Galbe, M., Gorwa-Grauslund, M. F., Lidén, G., & Zacchi, G. (2006). Bio-ethanol–the fuel of tomorrow from the residues of today.Trends in biotechnology, 24(12), 549-556.Pimentel, D. (2003). Ethanol fuels: energy balance, economics, and environmental impacts are negative. Natural Resources Res, 12, 127–34.Sarkar, N., Ghosh, S. K., Bannerjee, S., & Aikat, K. (2012). Bioethanol production from agricultural wastes: An overview. Renewable Energy, 37(1), 19-27.

Graph 2 : Retention time of ethanol for optimized amount of glucose by using GCMS headspace

Methodology

Results and Discussion

Figure 1 : Cellulose from Leucaena leucocephala seeds

Graph 1 : Percentage yield of ethanol for optimization of glucose

Amount of Glucose, g

Yield of Ethanol,

%

Figure 2 : Ethanol kept in vials while filtrated products kept in bottles

AUTOCLAVE OF EMPTY

FLASKS

OPTIMIZATION OF DAYS

OPTIMIZATION OF GLUCOSE

AMOUNT

OPTIMIZATION OF YEAST AMOUNT

OPTIMIZATION OF PH

FILTRATION DISTILLATION

ANALYSIS BY USING GCMS HEADSPACE

0