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Exopolysaccharide Production from Marine Bacteria and Its Applications
Published in Se-Kwon Kim, Marine Biochemistry, 2023
Prashakha J. Shukla, Shivang B. Vhora, Ankita G. Murnal, Unnati B. Yagnik, Maheshwari Patadiya
There are many techniques used to prevent fouling of artificial surfaces such as the use of biocide-coated surfaces (Nakayama et al., 1998; Morris and Walsh, 2000; Bearinger et al., 2003). However, natural antifouling chemicals produced by aquatic organisms or plants are the most promising methods for biofouling control. Coating surfaces with biological polymers or secondary metabolites can also prevent the formation of biofilm and, subsequently, biofouling. Guezennec et al. (2012) used EPSs from Alteromonas, Pseudomonas, and Vibrio spp. for an antibiofouling coating. They reported that EPSs can inhibit the primary colonization of bacteria, thereby minimizing successive biofouling. The presence of a polysaccharide film changes the hydrophobic/hydrophilic balance, which is important for adhering cells to surfaces (Yaskovich, 1998; Guezennec et al., 2012). Vibrio alginolyticus, V. proteolyticus, and V. vulnificus also are producers of antibiofouling EPSs (Qian et al., 2006; Kim et al., 2011).
Study of the impact of EMF on the reduction of biofouling in heat exchangers
Published in C. Guedes Soares, T.A. Santos, Trends in Maritime Technology and Engineering Volume 1, 2022
D. Boullosa-Falces, M.A. Gomez-Solaetxe, Z. Sanchez Varela, S. García, A. Trueba, D. Sanz
Therefore, it is necessary to use techniques to reduce the effect of biofouling on equipment as much as possible, to detect and mitigate its effect (Müller-Steinhagen et al. 2011). Normally, industries use physical or chemical techniques for the reduction, prevention and elimination of biofouling in industrial plants that use seawater as a cooling element (Dobretsov et al. 2013; Liu & Dong, 2008; Rajagopal et al. 2012). For an accessible surface, the most recommended technique for mitigating biofouling is the use of antifouling coatings. However, in equipment that is difficult to access, such as inside the tubes of a heat exchanger, the dosage of biocidal products is necessary. However, this type of treatment is intrusive with the equipment and aggressive with the environment (Eguía et al. 2007). Other types of techniques such as electromagnetic fields (EFM) are not harmful to the environment or intrusive to the equipment. Electromagnetic fields are created by an electric current and are directly proportional to the flow of that current. EFMs cause the precipitation of calcium carbonate (CaCO3) in fine particles that, after a period of crystallization, are deposited in the form of sludge on the surface of the heat exchanger walls that is easily removed and is carried away by the effect shear of the circulating water itself (Trueba et al. 2015).
Concrete deterioration mechanisms (B)
Published in Brian Cherry, Green Warren, Corrosion and Protection of Reinforced Concrete, 2021
Biofouling is the undesirable growth of biological matter, including bacteria, algae, fungi, and invertebrate organisms at liquid-solid interfaces. The detrimental effect of biofilms on skin friction has been well established and the increases in frictional resistance and resultant energy losses due to biofilms are of major concern to structure owners including hydroelectric power generators and water supply industries. It is the presence of biofilms in a frictional sense rather than their effect on the concrete degradation that is the problem (Andrewartha & Cribbin, 2009).
Assessing the effect of a thickness gradient on the shear stress profile at the epoxy/silicone interface of thin coatings subjected to transverse shear loads with finite element analyses
Published in The Journal of Adhesion, 2023
Melissa M. Gibbons, Stephen McNeela, James G. Kohl
Biofouling is the accumulation of living organisms on the surface of any structure submerged in seawater. The process begins almost immediately with the adsorption of organic particles that create a conditioning film that attracts primary colonizers, and if left unchecked results in colonization by macroscopic fouling like mussels and barnacles.[1] There are several negative outcomes when biofouling occurs on marine vessels. The irregular surface created by macroscopic biofouling increases drag, which results in increased fuel costs.[2] Biofouling has also been linked to the spread of invasive species to non-native environments.[3] Some of the first anti-fouling solutions were toxic paints that included copper or the organotin tributyltin. While these paints were easy to use and effective at controlling biofouling, the compounds slowly leached into the water, resulting in unintended negative environmental effects.[4,5] A stepwise prohibition of paints using biocidal organotin compounds was adopted by the International Maritime Organization in 2008.[6]
Occurrence of booster biocides in the global waters and a tiered assessment for their ecological risk to the aquatic system
Published in Human and Ecological Risk Assessment: An International Journal, 2022
Keyan Cui, Xianhai Yang, Huihui Liu
To prevent biofouling in the shipping industry, the submerged structures are usually coated with antifouling paint containing biocidal ingredients. With the ban of organotin compounds in antifouling paint, some emerging booster biocides were widely used. As a result, they were detected in the coastal environment worldwide, especially in the marinas and harbors with frequent boating activities (Kroon et al. 2020; Torres and De-la-Torre 2021). Due to the large-scale use and the persistence, Diuron and Irgarol 1051 were the most detected and reported biocides. Their highest concentrations exceeded the permissible limit proposed by the Dutch authorities (i.e., 430 and 24 ng/L for Diuron and Irgarol 1051, respectively) in many waters, such as the California marinas (Sapozhnikova et al. 2013), the coastal areas of Korea (Kim et al. 2014), Kurose River in Japan (Kaonga et al. 2015), the ports of Peninsular Malaysia (Ali et al. 2021). By comparison, other booster biocides (e.g., DCOIT, Chlorothalonil and Dichlofluanid) were prone to be degradable biologically or chemically in hours. Thus they were generally undetectable in waters, even though often occurred in sediments (Lam et al. 2017; Mukhtar et al. 2020; Abreu et al. 2021a). Additionally, some degradation products of the booster biocides were always detected in the environment, even higher than their parent compounds (Thomas et al. 2002; Hamwijk et al. 2005; Sapozhnikova et al. 2013; Lee et al. 2015).
Uniqueness of biofouling in forward osmosis systems: Mechanisms and control
Published in Critical Reviews in Environmental Science and Technology, 2018
Qiaoying Wang, Meng Hu, Zhiwei Wang, Weijie Hu, Jing Cao, Zhi-Chao Wu
Biofouling can be defined as the accumulation of microorganisms accompanied with agglomeration of extracellular substances on the membrane surface (Hori & Matsumoto, 2010). It includes the attachment of microorganisms on the membrane surface followed by gradual accumulation of more bacteria and extracellular materials to form a fouling layer, i.e., biofilm. Different from other fouling types, biofouling involves not only physicochemical interactions between membrane and bacteria, but also a biological process associated with the attached microorganisms. Since microorganisms can grow and multiply, an eventual biofilm could form even that 99.99% of microorganisms was removal from the system (Flemming & Schaule, 1988). Therefore, biofouling is inevitable in the presence of microorganisms and nutrients in the system.