Select Research Projects:
Production of Bioethanol from Agricultural Wastes
Olive oil industry represents one of the most important economic agro-food sectors in the Middle Eastern region. This industry generates huge amounts of waste materials which contain unexploited agricultural residues such as the olive mill wastewater (OMW) and olive mill solid wastes (OMSW). These waste materials pose acute environmental problems in the region. If pretreated to release fermentable sugars, the cheap, available and renewable lignocellulosic residues from OMSW and OMW can be used as a valuable feedstock for biofuel and bioproduct conversion. The low cost lignocellulosic materials from olive oil industry waste, combined with efficient conversion steps of all released sugars to ethanol and other value added products could substantially reduce the production cost of bioethanol. The main objectives of the proposed research are to discover an efficient approach to extract the lignocellulosic and other nitrogen sources from OMSW and OMW, to evaluate several pretreatment methods including the use of hydrolytic enzymes such as laccase and cellulose, and to recommend the best pretreatment scheme for the biomass contained in OMSW and OMW waste.
Researchers: Dr. Hassan Azaizeh (PI), Dr. Ahmed Tafesh, Dr. Jeries Jadoun, R&D Center, Galilee Society; and Prof. Carlos Dosoretz, Technion, Haifa. Fund: Ministry of Science and Technology.
Recombinant Yeasts for Effective Ethanol Production from Olive Mill Solid Wastes
Lignocellulose biomass is the main component of agricultural waste. Lignocellulosic raw materials are mainly composed of cellulose, hemicellulose, and lignin. The cellulose fraction is made up of glucose polymers, whereas the hemicellulose fraction is made up of a mixture of glucose, galactose, mannose, xylose and arabinose sugars. Xylose is found in hardwood and softwood hemicelluloses, whereas arabinose is a component in hemicellulose in certain agricultural crops, such as corn.
The cellulose and hemicellulose fractions can be hydrolyzed to monomeric sugars, which can be fermented to high-value products like ethanol and lactate. we propose to develop molecular method or tool for obtaining recombinant, S. cerevisiae, which ferments lignocellulose raw materials to ethanol, that includes transformation of genes encoding the enzymes xylose reductase and xylitol dehydrogenase obtained from P. stipitis, and xylulokinase obtained from S. cerevisiae into industrial yeast strains of S. cerevisiae and to perform mutant strain which grows on minimum nutrient containing xylose as sole carbon source. The produced ethanol can serve as an environmentally acceptable liquid fuel, it is an energy form that is CO2 neutral, and hence it does not contribute to global warming.
Researchers: Dr. Naim Najami-post doctorate- and Dr. Hassan Azaizeh (supervisor), R&D Center, the Galilee Society. Fund: Ministry of Science and Technology (Levi-Eshkol grant).