{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T15:12:58Z","timestamp":1789139578868,"version":"build-2803163510"},"reference-count":31,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2023,9,30]],"date-time":"2023-09-30T00:00:00Z","timestamp":1696032000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"USA National Science Foundation IRES Program","award":["1458962"],"award-info":[{"award-number":["1458962"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Life"],"abstract":"<jats:p>Microalgae represent a promising source of triglycerides and free fatty acids, synthesized in the form of lipids, for use in renewable fuels and chemicals. One challenge is the ability to efficiently recover the lipids from within the microalgae cell. Although various techniques have been studied individually, a comprehensive study of extraction techniques using consistent experimental and analytical methodology is missing. This study aims to provide this unifying comparison using the common microalgae strain Chlorella vulgaris. The factors that were surveyed and then optimized to achieve maximum extraction efficiency included the solvent type; mechanical pre-treatment using a ball mill at a variety of grinding speeds; microalgae-to-solvent ratio; extraction facilitated by microwave; extraction facilitated by sonication; extraction facilitated using increased temperature; and extraction facilitated by in situ transesterification to convert the lipids into esters prior to extraction. The optimum conditions determined during these studies were utilizing methanol as the solvent, with ball mill pretreatment at a grinding speed of 500 rpm, and a 1:9 microalgae to solvent ratio. When used in combination with microwave-assisted extraction at a temperature of 140 \u00b0C, approximately 24 wt% of the initial lipids were recovered. Recoveries of over 70 wt% were obtained without a microwave at extraction temperatures of over 200 \u00b0C.<\/jats:p>","DOI":"10.3390\/life13101997","type":"journal-article","created":{"date-parts":[[2023,10,1]],"date-time":"2023-10-01T16:58:09Z","timestamp":1696179489000},"page":"1997","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["A Comprehensive Study of Techniques to Optimize the Extraction of Lipids from the Autotrophic Strain of the Microalgae Chlorella vulgaris"],"prefix":"10.3390","volume":"13","author":[{"given":"Ian","family":"Foerster","sequence":"first","affiliation":[{"name":"Chemical Engineering Department, University of North Dakota, 243 Centennial Drive Stop 7101, Grand Forks, ND 58202, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wayne","family":"Seames","sequence":"additional","affiliation":[{"name":"Chemical Engineering Department, University of North Dakota, 243 Centennial Drive Stop 7101, Grand Forks, ND 58202, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jasmine","family":"Oleksik","sequence":"additional","affiliation":[{"name":"Energy & Environmental Research Center, University of North Dakota, 15 N. 23rd St., Grand Forks, ND 58202, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2318-5883","authenticated-orcid":false,"given":"Alena","family":"Kubatova","sequence":"additional","affiliation":[{"name":"Chemistry Department, University of North Dakota, 151 Cornell Street Stop 9024, Grand Forks, ND 58202, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew","family":"Ross","sequence":"additional","affiliation":[{"name":"School of Chemical and Process Engineering, University of Leeds, 209 Clarendon Road, Leeds LS2 9JT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"87","DOI":"10.1016\/j.rser.2019.01.064","article-title":"Biomass recovery and lipid leaching processes for microalgae biofuels production: A review","volume":"107","author":"Menegazzo","year":"2019","journal-title":"Renew. 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