{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T18:28:14Z","timestamp":1790447294434,"version":"4.1.0"},"reference-count":31,"publisher":"Public Library of Science (PLoS)","issue":"12","license":[{"start":{"date-parts":[[2023,12,15]],"date-time":"2023-12-15T00:00:00Z","timestamp":1702598400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100017691","name":"Guangxi Key Research and Development Program","doi-asserted-by":"publisher","award":["2023AB01132 and 2021AB27009"],"award-info":[{"award-number":["2023AB01132 and 2021AB27009"]}],"id":[{"id":"10.13039\/501100017691","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:p><jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" ext-link-type=\"uri\" xlink:href=\"https:\/\/www.sciencedirect.com\/topics\/biochemistry-genetics-and-molecular-biology\/carotenoid\" xlink:type=\"simple\">Carotenoids<\/jats:ext-link> are antioxidants, which reduce various chronic diseases of human, and have many industrial applications. The halophilic <jats:italic><jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" ext-link-type=\"uri\" xlink:href=\"https:\/\/www.sciencedirect.com\/topics\/biochemistry-genetics-and-molecular-biology\/dunaliella\" xlink:type=\"simple\">Dunaliella<\/jats:ext-link> parva<\/jats:italic> (<jats:italic>D<\/jats:italic>. <jats:italic>parva<\/jats:italic>) is rich in carotenoids. The compounds CaCl<jats:sub>2<\/jats:sub> and PEG are the popular metabolic enhancers. To further enhance carotenogenesis, <jats:italic>D<\/jats:italic>. <jats:italic>parva<\/jats:italic> was treated with two compounds polyethylene glycol (PEG) and CaCl<jats:sub>2<\/jats:sub>. Application of CaCl<jats:sub>2<\/jats:sub> and PEG enhanced the carotenoids contents and the antioxidant activities of carotenoids compared to control group (no treatment of CaCl<jats:sub>2<\/jats:sub> or PEG). The highest carotenoids contents were obtained by treating <jats:italic>D<\/jats:italic>. <jats:italic>parva<\/jats:italic> with 40 ppm CaCl<jats:sub>2<\/jats:sub> (3.11 mg\/g dry weight, DW) and 80 ppm PEG (2.78 mg\/g DW) compared with control group (1.96 mg\/g DW). When <jats:italic>D<\/jats:italic>. <jats:italic>parva<\/jats:italic> was treated with 40 ppm CaCl<jats:sub>2<\/jats:sub> and 80 ppm PEG, protein contents reached the highest values (90.28 mg\/g DW and 89.57 mg\/g DW) compared to that of control group (73.42 mg\/g DW). The <jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" ext-link-type=\"uri\" xlink:href=\"https:\/\/www.sciencedirect.com\/topics\/biochemistry-genetics-and-molecular-biology\/antioxidant-activity\" xlink:type=\"simple\">antioxidant activities<\/jats:ext-link> of carotenoids samples were determined. Generally, the antioxidant activities of carotenoids from <jats:italic>D<\/jats:italic>. <jats:italic>parva<\/jats:italic> treated with PEG and CaCl<jats:sub>2<\/jats:sub> were superior to that of control group. The antioxidant activities of carotenoids mainly contained reducing power, hydroxyl radical scavenging activity and superoxide radical scavenging activity. The reducing powers of carotenoids extracts from 20 ppm CaCl<jats:sub>2<\/jats:sub> group (2.07%\/mg carotenoids) and 120 ppm PEG group (1.59%\/mg carotenoids) were significantly higher than that of control group (&lt;1.25%\/mg carotenoids). The superoxide radical scavenging activities of carotenoids extracts from 40 ppm CaCl<jats:sub>2<\/jats:sub> group (70.33%\/mg carotenoids) and 80 ppm PEG group (65.94%\/mg carotenoids) were significantly higher than that of control group (&lt;55%\/mg carotenoids). This paper laid a foundation for massive accumulation of carotenoids in microalga <jats:italic>D<\/jats:italic>. <jats:italic>parva<\/jats:italic>.<\/jats:p>","DOI":"10.1371\/journal.pone.0295973","type":"journal-article","created":{"date-parts":[[2023,12,15]],"date-time":"2023-12-15T18:38:12Z","timestamp":1702665492000},"page":"e0295973","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":9,"title":["Physiological changes of microalga Dunaliella parva under the treatment of PEG, CaCl2"],"prefix":"10.1371","volume":"18","author":[{"given":"Qiman","family":"Zou","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Limei","family":"Huang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jinghui","family":"Gu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bingbing","family":"Pang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1447-6117","authenticated-orcid":true,"given":"Changhua","family":"Shang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2023,12,15]]},"reference":[{"key":"pone.0295973.ref001","doi-asserted-by":"crossref","first-page":"1238","DOI":"10.1111\/tpj.16009","article-title":"The 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