2007 Annual Report 1a.Objectives (from AD-416) To develop unique fermentation processes using biodiesel glycerol as the primary substrate for the production of sugar-based polyols, arabitol and/or xylitol. 1b.Approach (from AD-416) To conduct species/strain screening and partial characterization of the selected microorganisms, define biodiesel glycerol for use as a suitable culture substrate, and develop fermentation processes for high productivity of the targeted sugar-based polyols. 3.Progress Report The report documents research conducted under a reimbursable agreement between The Agriculture Research Service (ARS) and The University of Akron (UA) funded by the United Soybean Board’s (USB) New Uses Program. Additonal details about this research can be found in the report for the parent project 3620-41000-113-00D, entitled "New Microbial Systems for Utilization of Glycerol and Plant Lipids." Arabitol and Xylitol from Biodiesel Glycerol: The main objective of the study for Fiscal Year 2007 is to identify active microbial strains that are capable of arabitol or xylitol production from glycerol feedstock. A number of tasks have been completed that include establishing selection medium and assay methods, searching ARS Culture Collection and microbial genome databases, and screening for productive species/strains. A total of 138 yeast strains from the ARS Culture Collection (91 belonging to Debaryomyces hansenii and its closely related species and 47 belonging to Metschnikowia reukaufii and its closely related species) were examined for their ability to produce arabitol/xylitol. During the study, the experimental results have been exchanged and discussed between ARS and UA principal investigators mainly by email and facsimile and occasionally by conference calls. Research progress is also monitored by quarterly reports prepared by ARS and UA researchers and evaluated by a USB committee. A Material Transfer Agreement (MTA) has been established between ARS and UA for transferring the identified active strains from ARS to UA for fermentation engineering studies. This agreement is undergoing renewal.