Industrial Oil Products Program
Wednesday morning
Chair(s): M. Dasari, Feed Energy Co., USA and V. Wyatt, USDA, ARS, ERRC, USA
Synthesis of Nanoscale, Monodisperse, Functionalized, Hyperbranched Oligomers Based on Glycerol and Fatty Acids., J.A. Zerkowski, A. Nunez, D.K.Y. Solaiman, USDA, ARS, ERRC, Wyndmoor, PA USA.
Polyesters derived from biorenewables are attractive synthetic targets and are receiving attention for uses such as controlled-release gel matrices. One drawback to these polymers, however, is that they are generally prepared in an “all-at-once” manner that yields a distribution of products, both in terms of size and architecture (degree of branching). A more significant limitation is that this method also precludes the selective incorporation of functional groups at a given site, such as the core or the periphery, or at some desired ratio. By contrast, a stepwise, iterative approach permits unambiguous construction of oligo/polyesters of defined shape and size. This talk will present our results on the stepwise construction of hyperbranched oligomers from glycerol, dicarboxylic acids, and other functionalized building blocks using esterification reagents and, to assemble the final oligomer, the azide-alkyne click reaction. An azido fatty acid that we have prepared is employed in this step. The oligomers are in the size range of 5-10 nm (depending on the building blocks) and 10 kDa and can exhibit upwards of 20 functional groups at their periphery. Alternatively, the synthesis can be designed so that one single reactive functional group can be localized at the surface of the oligomers.
Glycerin-based Polyols of High Biobased Content for Polyurethane Foams., Z. Petrovic, I. Javni, M. Ionescu, D.-P. Hong, Pittsburg State University, Pittsburg, KS, USA.
Utilization of glycerin for polyols for polyurethane industry became interesting as a result of availability from biodiesel production. However, polyols for polyurethane foams have to satisfy a range of requirements in order to be accepted by industry such as clarity (single phase), acceptable viscosity < 10 Pa.s, right OH number (100-600 mg KOH/g), good color (not too dark);functionality: 2-10;acid value bellow 2, miscible with organic solvents (1:1) and water (10%), high glycerin content >50% and high bio-based content >80%. We have developed a family of polyols by modifying polyglycerin to control OH number, viscosity, functionality and solubility, and tested them in rigid foams. Properties of polyols and foams are discussed.
Conversion of Glycerol to Lipids via Oleaginous Microorganisms., J. M. Thomas, R. Hernandez, T. French, W. Holmes, E. Alley, Mississippi State University.
The growing popularity of biodiesel as an alternative to petroleum-derived diesel fuel has created a dramatic increase in the production of crude glycerol. Currently crude glycerol has a low market value and many biodiesel producers are treating the crude glycerol as a waste product. If biodiesel is to succeed as an alternative to petroleum-based fuels, it is essential that the crude glycerol produced is processed/refined cost effectively into a value-added product. Oleaginous microorganisms have the ability to use many different types of carbon sources and convert them into oils that can then be used for the production of fuels. The purpose of this study is to investigate the feasibility of oleaginous microorganisms to utilize glycerol as a carbon source for the production of oils. The study will focus on the oleaginous yeast species Rhodotorula glutinis. The study will investigate the growth and lipid production kinetics of R. glutinis grown on pure glycerol as the sole carbon source.
A Metabolic Approach for Increasing Lipid Storage in Y. Lipolytica Grown on Glycerol., C.E. Hodgman, B.Y. Tao, Purdue University, West Lafayette, IN, USA.
By 2022, biodiesel is mandated to reach 1 billion gallons of annual production. Biodiesel is made from the lipids of any biological material. To make biodiesel, 90% of the lipids are converted to biodiesel while 10% is leftover as industrial glycerol. The success of the biodiesel industry depends on: 1) finding additional sources of oil and 2) a profitable use for industrial glycerol. Through fermentation, glycerol can be used as a feed stock for the oleaginous yeast, Y. lipolytica, and converted back into oil for additional biodiesel production. Y. lipolytica is known to grow well on industrial glycerol, store large amounts of lipids, and is relatively easy to genetically manipulate. We are looking to increase the rate of glycerol consumption in the cell to increase the rate of lipid storage. This is accomplished by overexpressing glycerol 3-phosphate dehydrogenase, a key enzyme in glycerol metabolism. The yeast is grown aerobically in a continuous bioreactor with excess glycerol under nitrogen limiting conditions to induce lipid storage. Preliminary results with the native strain yield 14 g dry biomass/L and 4 g lipids/L (30% total mass) at steady state. The genetically modified strain is compared to the wild type strain in terms of total dry mass, percent and composition of lipids, and rate of glycerol consumption.