Microalgae hold much promise as a feedstock in liquid biofuel production. Lipid content of microalgae cells range from 30-80% dry weight of biomass. It is projected that microalgae can produce between 1,000-6,500 gallons/acre/year of oil. Currently, production of industrial algae operates in open raceway ponds that use minimal capital and energy inputs to culture algae. Raceway ponds can also be used to grow microalgae from municipal waste streams. Although high biomass productivity can be achieved in these systems, there remains a large production gap between large volumes of biomass cultivation and high lipid content from microalgae cells. Low lipid content has been ameliorated through laboratory manipulations of nitrogen availability and light intensity. This two-part project measured microalgae lipid levels in open raceway ponds located at the San Luis Obispo Water Reclamation Facility (SLO WRF) grown in primary clarifier effluent and then performed nitrogen depletion and light-shift methods on cultures to increase triglyceride (TAG) content. The raceway ponds reached maximum biomass productivity of 24 g/m2-day, but with minimal TAG reserves. Optimization of both biomass productivity and TAG content can be achieved in April and September with 13 g/m2-day productivity and 13% TAG content. Investigation of increased TAG production responses were performed on wastewater microalgae (predominately Scenedesmus sp.) through N-depletion and three light treatments: light-shift on day 3 (before N-depletion), light-shift on day 5 (near N-depletion), and a double-illumination treatment. Highest levels of TAG content were observed in the double-illumination treatment and reached a maximum of 49% TAG in 9 days.
","abstract_html":"<p>Microalgae hold much promise as a feedstock in liquid biofuel production. Lipid content of microalgae cells range from 30-80% dry weight of biomass. It is projected that microalgae can produce between 1,000-6,500 gallons/acre/year of oil. Currently, production of industrial algae operates in open raceway ponds that use minimal capital and energy inputs to culture algae. Raceway ponds can also be used to grow microalgae from municipal waste streams. Although high biomass productivity can be achieved in these systems, there remains a large production gap between large volumes of biomass cultivation and high lipid content from microalgae cells. Low lipid content has been ameliorated through laboratory manipulations of nitrogen availability and light intensity. This two-part project measured microalgae lipid levels in open raceway ponds located at the San Luis Obispo Water Reclamation Facility (SLO WRF) grown in primary clarifier effluent and then performed nitrogen depletion and light-shift methods on cultures to increase triglyceride (TAG) content. The raceway ponds reached maximum biomass productivity of 24 g/m<sup>2</sup>-day, but with minimal TAG reserves. Optimization of both biomass productivity and TAG content can be achieved in April and September with 13 g/m<sup>2</sup>-day productivity and 13% TAG content. Investigation of increased TAG production responses were performed on wastewater microalgae (predominately <em>Scenedesmus sp</em>.) through N-depletion and three light treatments: light-shift on day 3 (before N-depletion), light-shift on day 5 (near N-depletion), and a double-illumination treatment. Highest levels of TAG content were observed in the double-illumination treatment and reached a maximum of 49% TAG in 9 days.</p>","abstract_has_math":false,"creators":["Kelley, James Edward"],"institution":null,"degree_name":"MS in Biological Sciences","degree_level":null,"degree_discipline":"Biological Sciences","degree_department":null,"school":null,"contributors":["Mark Moline"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2013,"date_issued":"2013-12-01T08:00:00Z","date_published":"2013-12-01T08:00:00Z","updated_at":"2026-07-24T01:32:50Z","subjects":["Fatty acid methykl esters (FAMEs)","Lipids","Triglycerides (TAGs)","Light-shift","nitrogen depletion","light intensity","gas chromatography mass spectrometry","Analytical Chemistry","Biology","Environmental Engineering","Organic Chemistry"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["10.15368/theses.2013.204"],"render_values":[{"text":"10.15368/theses.2013.204","href":"https://doi.org/10.15368/theses.2013.204","code":true}]}]},"links":{"outbound_url":"https://digitalcommons.calpoly.edu/theses/1123","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Mark Moline"]},{"key":"dc:creator","label":"Author","values":["Kelley, James Edward"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["2014-12-09T08:00:00Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Biological Sciences"]},{"key":"thesis:degree_name","label":"Degree Name","values":["MS in Biological Sciences"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Fatty acid methykl esters (FAMEs)","Lipids","Triglycerides (TAGs)","Light-shift","nitrogen depletion","light intensity","gas chromatography mass spectrometry","Analytical Chemistry","Biology","Environmental Engineering","Organic Chemistry"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://digitalcommons.calpoly.edu/theses/1123","10.15368/theses.2013.204"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Microalgae hold much promise as a feedstock in liquid biofuel production. Lipid content of microalgae cells range from 30-80% dry weight of biomass. It is projected that microalgae can produce between 1,000-6,500 gallons/acre/year of oil. Currently, production of industrial algae operates in open raceway ponds that use minimal capital and energy inputs to culture algae. Raceway ponds can also be used to grow microalgae from municipal waste streams. Although high biomass productivity can be achieved in these systems, there remains a large production gap between large volumes of biomass cultivation and high lipid content from microalgae cells. Low lipid content has been ameliorated through laboratory manipulations of nitrogen availability and light intensity. This two-part project measured microalgae lipid levels in open raceway ponds located at the San Luis Obispo Water Reclamation Facility (SLO WRF) grown in primary clarifier effluent and then performed nitrogen depletion and light-shift methods on cultures to increase triglyceride (TAG) content. The raceway ponds reached maximum biomass productivity of 24 g/m2-day, but with minimal TAG reserves. Optimization of both biomass productivity and TAG content can be achieved in April and September with 13 g/m2-day productivity and 13% TAG content. Investigation of increased TAG production responses were performed on wastewater microalgae (predominately Scenedesmus sp.) through N-depletion and three light treatments: light-shift on day 3 (before N-depletion), light-shift on day 5 (near N-depletion), and a double-illumination treatment. Highest levels of TAG content were observed in the double-illumination treatment and reached a maximum of 49% TAG in 9 days.
"]},{"key":"dc:title","label":"Title","values":["Lipid Production by Microalgae Treating Municipal Wastewater"]}]}],"canonical_facts":{"dc:contributor":["Mark Moline"],"dc:creator":["Kelley, James Edward"],"dc:date.available":["2014-12-09T08:00:00Z"],"dc:description.abstract":["Microalgae hold much promise as a feedstock in liquid biofuel production. Lipid content of microalgae cells range from 30-80% dry weight of biomass. It is projected that microalgae can produce between 1,000-6,500 gallons/acre/year of oil. Currently, production of industrial algae operates in open raceway ponds that use minimal capital and energy inputs to culture algae. Raceway ponds can also be used to grow microalgae from municipal waste streams. Although high biomass productivity can be achieved in these systems, there remains a large production gap between large volumes of biomass cultivation and high lipid content from microalgae cells. Low lipid content has been ameliorated through laboratory manipulations of nitrogen availability and light intensity. This two-part project measured microalgae lipid levels in open raceway ponds located at the San Luis Obispo Water Reclamation Facility (SLO WRF) grown in primary clarifier effluent and then performed nitrogen depletion and light-shift methods on cultures to increase triglyceride (TAG) content. The raceway ponds reached maximum biomass productivity of 24 g/m2-day, but with minimal TAG reserves. Optimization of both biomass productivity and TAG content can be achieved in April and September with 13 g/m2-day productivity and 13% TAG content. Investigation of increased TAG production responses were performed on wastewater microalgae (predominately Scenedesmus sp.) through N-depletion and three light treatments: light-shift on day 3 (before N-depletion), light-shift on day 5 (near N-depletion), and a double-illumination treatment. Highest levels of TAG content were observed in the double-illumination treatment and reached a maximum of 49% TAG in 9 days.
"],"dc:identifier":["https://digitalcommons.calpoly.edu/theses/1123","10.15368/theses.2013.204"],"dc:subject":["Fatty acid methykl esters (FAMEs)","Lipids","Triglycerides (TAGs)","Light-shift","nitrogen depletion","light intensity","gas chromatography mass spectrometry","Analytical Chemistry","Biology","Environmental Engineering","Organic Chemistry"],"dc:title":["Lipid Production by Microalgae Treating Municipal Wastewater"],"thesis:degree_discipline":["Biological Sciences"],"thesis:degree_name":["MS in Biological Sciences"]},"updated_at":"2026-07-24T01:32:50Z"}