Editing Biofilm (section)

=== In industry ===
{{See also|Biofilms in industry}}
Biofilms can also be harnessed for constructive purposes. For example, many [[sewage treatment]] plants include a [[secondary treatment]] stage in which waste water passes over biofilms grown on filters, which extract and digest organic compounds. In such biofilms, bacteria are mainly responsible for removal of organic matter ([[Biochemical oxygen demand|BOD]]), while [[protozoa]] and [[rotifer]]s are mainly responsible for removal of suspended solids (SS), including pathogens and other microorganisms. [[Slow sand filter]]s rely on biofilm development in the same way to filter surface water from lake, spring or river sources for drinking purposes. What is regarded as clean water is effectively a waste material to these microcellular organisms. Biofilms can help eliminate petroleum oil from contaminated oceans or marine systems. The oil is eliminated by the [[microbial biodegradation|hydrocarbon-degrading]] activities of communities of [[hydrocarbonoclastic bacteria]] (HCB).<ref name="chapter9">{{cite book |title=Microbial Biodegradation: Genomics and Molecular Biology |vauthors=Martins dos Santos VA, Yakimov MM, Timmis KN, Golyshin PN |publisher=Horizon Scientific Press |year=2008 |isbn=978-1-904455-17-2 |pages=[https://archive.org/details/microbialbiodegr0000unse/page/1971 1971] |chapter=Genomic Insights into Oil Biodegradation in Marine Systems |chapter-url=https://books.google.com/books?id=wx6v3TIkzXUC&pg=PA1971 | veditors = Díaz E |url=https://archive.org/details/microbialbiodegr0000unse/page/1971}}</ref>
Biofilms are used in [[microbial fuel cells]] (MFCs) to generate electricity from a variety of starting materials, including complex organic waste and renewable biomass.<ref name="LearGLewisGD" /><ref>{{cite journal |vauthors = Wang VB, Chua SL, Cai Z, Sivakumar K, Zhang Q, Kjelleberg S, Cao B, Loo SC, Yang L |title = A stable synergistic microbial consortium for simultaneous azo dye removal and bioelectricity generation |journal = Bioresource Technology |volume = 155 |pages = 71–76 |date = March 2014 |pmid = 24434696 |doi = 10.1016/j.biortech.2013.12.078 |bibcode = 2014BiTec.155...71W }}</ref><ref>{{cite journal |vauthors = Wang VB, Chua SL, Cao B, Seviour T, Nesatyy VJ, Marsili E, Kjelleberg S, Givskov M, Tolker-Nielsen T, Song H, Loo JS, Yang L |title = Engineering PQS biosynthesis pathway for enhancement of bioelectricity production in pseudomonas aeruginosa microbial fuel cells |journal = PLOS ONE |volume = 8 |issue = 5 |pages = e63129 |year = 2013 |pmid = 23700414 |pmc = 3659106 |doi = 10.1371/journal.pone.0063129 |doi-access = free |bibcode = 2013PLoSO...863129W }}</ref>
Biofilms are also relevant for the improvement of metal dissolution in [[bioleaching]] industry,<ref name="pmid23720034">{{cite journal |vauthors = Vera M, Schippers A, Sand W |title = Progress in bioleaching: fundamentals and mechanisms of bacterial metal sulfide oxidation—part A |journal = Appl. Microbiol. Biotechnol. |volume = 97 |issue = 17 |pages = 7529–41 |date = September 2013 |pmid = 23720034 |doi = 10.1007/s00253-013-4954-2 |s2cid = 17677624 }}</ref> and aggregation of microplastics pollutants for convenient removal from the environment.<ref>{{Cite journal | vauthors = Chan SY, Wong MW, Kwan BT, Fang JK, Chua SL |date=2022-10-12 |title=Microbial–Enzymatic Combinatorial Approach to Capture and Release Microplastics |journal=Environmental Science & Technology Letters |volume=9 |issue=11 |language=en |pages=975–982 |doi=10.1021/acs.estlett.2c00558 |bibcode=2022EnSTL...9..975C |s2cid=252892619 |issn=2328-8930}}</ref><ref>{{Cite journal | vauthors = Liu SY, Leung MM, Fang JK, Chua SL |date=2021-01-15 |title=Engineering a microbial 'trap and release' mechanism for microplastics removal |journal=Chemical Engineering Journal |language=en |volume=404 |pages=127079 |doi=10.1016/j.cej.2020.127079 |bibcode=2021ChEnJ.40427079L |hdl=10397/88307 |s2cid=224972583 |issn=1385-8947|hdl-access=free }}</ref>