(169f) The Dynamics of Biodiesel Profile and Fungal Diversity of Activated Sludge during Lipid Accumulation on Acetic Acid

Recent studies indicated that the microbial consortia of wastewater treatment plant (WWTP) activated sludge feeding on acetic acid can accumulate lipids, which can be transesterified into biodiesel. The composition of the raw activated sludge, however changes significantly with the fluctuations of operational and environmental conditions in a WWTP. The variations in raw activated sludge composition may pose additional processing cost after extraction and transesterification of the lipids if there is significant variation of the biodiesel profile (measured as fatty acid methyl esters or FAMEs) among raw activated sludges. This study describes the changes on biodiesel profile during lipid accumulation on acetic acid. The changes on the diversity of fungal community are also correlated to the changes in biodiesel profile. The findings suggest that even with variations in the biodiesel profiles from lipids of raw activated sludge, the enhancement of lipid content by feeding on acetic acid induces speciation of microbial community, specifically fungi, resulting in the homogenization of biodiesel profiles.