{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T18:06:53Z","timestamp":1775844413028,"version":"3.50.1"},"reference-count":42,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,5,2]],"date-time":"2025-05-02T00:00:00Z","timestamp":1746144000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"national funds through FCT\/MCTES (PIDDAC): LEPABE","award":["UIDB\/00511\/2020"],"award-info":[{"award-number":["UIDB\/00511\/2020"]}]},{"name":"national funds through FCT\/MCTES (PIDDAC): LEPABE","award":["UIDP\/00511\/2020"],"award-info":[{"award-number":["UIDP\/00511\/2020"]}]},{"name":"national funds through FCT\/MCTES (PIDDAC): LEPABE","award":["LA\/P\/0045\/2020"],"award-info":[{"award-number":["LA\/P\/0045\/2020"]}]},{"name":"national funds through FCT\/MCTES (PIDDAC): LEPABE","award":["2020.09538.BD"],"award-info":[{"award-number":["2020.09538.BD"]}]},{"name":"ALiCE","award":["UIDB\/00511\/2020"],"award-info":[{"award-number":["UIDB\/00511\/2020"]}]},{"name":"ALiCE","award":["UIDP\/00511\/2020"],"award-info":[{"award-number":["UIDP\/00511\/2020"]}]},{"name":"ALiCE","award":["LA\/P\/0045\/2020"],"award-info":[{"award-number":["LA\/P\/0045\/2020"]}]},{"name":"ALiCE","award":["2020.09538.BD"],"award-info":[{"award-number":["2020.09538.BD"]}]},{"name":"Portuguese Foundation for Science and Technology\u2014FCT Henrique Sousa","award":["UIDB\/00511\/2020"],"award-info":[{"award-number":["UIDB\/00511\/2020"]}]},{"name":"Portuguese Foundation for Science and Technology\u2014FCT Henrique Sousa","award":["UIDP\/00511\/2020"],"award-info":[{"award-number":["UIDP\/00511\/2020"]}]},{"name":"Portuguese Foundation for Science and Technology\u2014FCT Henrique Sousa","award":["LA\/P\/0045\/2020"],"award-info":[{"award-number":["LA\/P\/0045\/2020"]}]},{"name":"Portuguese Foundation for Science and Technology\u2014FCT Henrique Sousa","award":["2020.09538.BD"],"award-info":[{"award-number":["2020.09538.BD"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Wastewater (WW) treatment using biofilms harboring bacteria and microalgae is considered a promising polishing solution to improve current treatment technologies present in wastewater treatment plants (WWTPs), but their interaction in a sessile community remains to be understood. In this work, multi-species biofilms of Chlorella vulgaris, Chlorella sorokiniana, or Scenedesmus obliquus were selected as representative microalgae species of interest for WW bioremediation, and Rhodococcus fascians, Acinetobacter calcoaceticus, or Leucobacter sp. were selected as the bacteria for co-cultivation in a synthetic WW since they are normally found in WW treatment processes. The attached consortia were developed in specific carriers (K5 carriers) for 168 h, and their biofilm formation ability was evaluated in a profilometer and via scanning electron microscopy (SEM) imaging. From the selected microorganisms, C. sorokiniana was the microalga that adapted best to co-cultivation with R. fascians and A. calcoaceticus, developing a thicker biofilm in these two consortia (3.44 \u00b1 0.5 and 4.51 \u00b1 0.8 \u00b5m, respectively) in comparison to the respective axenic cultures (2.55 \u00b1 0.7 \u00b5m). In contrast, Leucobacter sp. did not promote biofilm growth in association with C. vulgaris and C. sorokiniana, while S. obliquus was not disturbed by the presence of this bacterium. Some bacterial clusters were observed through SEM, especially in A. calcoaceticus cultures in the presence of microalgae. In some combinations (especially when C. vulgaris was co-cultivated with bacteria), the presence of bacteria was able to increase the number of microalga cells adhered to the K5 carrier. This study shows that biofilm development was distinctly dependent on the co-cultivated species, where synergy in biofilm formation was highly dependent on the microalgae and bacteria species. Moreover, profilometry appears to be a promising method for biofilm analyses.<\/jats:p>","DOI":"10.3390\/microorganisms13051060","type":"journal-article","created":{"date-parts":[[2025,5,2]],"date-time":"2025-05-02T07:44:58Z","timestamp":1746171898000},"page":"1060","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Qualitative Assessment of Microalgae\u2013Bacteria Biofilm Development on K5 Carriers: Photoheterotrophic Growth in Wastewater"],"prefix":"10.3390","volume":"13","author":[{"given":"Henrique","family":"Sousa","sequence":"first","affiliation":[{"name":"LEPABE\u2014Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"},{"name":"ALiCE\u2014Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"given":"Kerry A.","family":"Kinney","sequence":"additional","affiliation":[{"name":"Architectural, and Environmental Engineering, Department of Civil, University of Texas, 301E E Dean Keeton St. c1700, Austin, TX 78712, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3719-4454","authenticated-orcid":false,"given":"C\u00e1tia A.","family":"Sousa","sequence":"additional","affiliation":[{"name":"LEPABE\u2014Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"},{"name":"ALiCE\u2014Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"},{"name":"ISEP\/P.PORTO, School of Engineering, Polytechnic of Porto, Rua Dr. Ant\u00f3nio Bernardino de Almeida, 431, 4249-015 Porto, Portugal"},{"name":"CIETI, Center for Innovation in Engineering and Industrial Technology, School of Engineering, Polytechnic of Porto, Rua Dr. Ant\u00f3nio Bernardino de Almeida, 431, 4249-015 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3355-4398","authenticated-orcid":false,"given":"Manuel","family":"Sim\u00f5es","sequence":"additional","affiliation":[{"name":"LEPABE\u2014Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"},{"name":"ALiCE\u2014Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"262","DOI":"10.1007\/s12088-021-00924-8","article-title":"Microalgal-Bacterial Consortia as Future Prospect in Wastewater Bioremediation, Environmental Management and Bioenergy Production","volume":"61","author":"Khoo","year":"2021","journal-title":"Indian J. 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