Dr. Shuyi Wang is a research scientist in the Scripps Institution of Oceanography (SIO) at the University of California, San Diego (UCSD). Dr. Wang completed her Ph.D. degree in Environmental Engineering from Duke University in 2009. She also holds a B.S. and M.S. degree in Environmental Engineering from Tsinghua University. She is a licensed Professional Engineer (P.E.) in California. She has extensive experience in microbial biology and 8 years’ practice in engineering.
Abstract
Microalgae require major nutrients such as nitrogen and phosphate for growth. One of the challenges to grow algae at a large scale for sustainable biofuel production is to identify sources of such nutrients. Extraction of lipids during biofuel production leaves a residue rich in nitrogen, which could be recycled to grow more algae. Diverse marine and freshwater strains were screened for their ability to use organic nitrogen sources including glutamic acid, casein, BSA and lipid extraction residues. Some strains such as Haematococcus were found to be promising algal candidates that can grow on byproducts of lipid extraction. Nearly total recycling of nitrogen might eventually be achieved for these strains in biofuel ponds.
Microalgal strains for algal biofuels production in outdoor ponds will need to have robust growth and grazer resistance. A small pond in the San Elijo Lagoon estuary in California was chosen to serve as a model pond due to its visibly high chlorophyll content. Profiles of microalgal assemblages from water samples collected from April 2011 to Jan 2012 were obtained by constructing 18S rDNA clone libraries. Pond assemblages were found to be dominated by green algae Picochlorum sp. and Picocystis sp. throughout the year. However, changes of temperature, salinity or irradiance may have caused the bloom of diatom Chaetoceros sp. in June 2011. Isolates of these microalgae were obtained and characterized. Isolate Picochlorum sp. was studied as a model strain and grown in ponds to examine its potential for biofuels in terms of grazer resistance and lipid yield.
