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Biomacromolecules from Marine Organisms and Their Biomedical Application
Published in Se-Kwon Kim, Marine Biochemistry, 2023
Pitchiah Sivaperumal, Kannan Kamala, Ganapathy Dhanraj
Extracellular Polymeric Substances (EPSs): Various marine microbes produced complex substances composed of carbohydrates, proteins, humic substances, lipids and nucleic acids (Manivasagan and Kim, 2014) are known as EPSs. It consists of organic and inorganic substances along with acetate, pyruvate, phosphate and succinate moieties (Priyanka and Ena, 2020). Enormous EPS-producing Vibrio furnissi VB0S3 was isolated from the coastal area of Goa (Bramhachari et al., 2007). Similarly, an Enterobacter cloaca was isolated from marine sediment, which has produced enormous acidic EPS exhibits significant emulsifying properties (Iyer et al., 2005). A gram-positive bacteria Planococcus maitriensis was isolated from the coastal waters of Bhavnagar in India produced an EPS used in oil recovery and bioremediation of oil (Priyanka and Ena, 2020). Marine bacterium Alteronomas sp., Pseudoaltromonas sp., and Vibrio sp., produced unique EPSs ranged from 0.5 to 4 g per liter of sugar base medium (Raza et al., 2011). The EPS from Vibrio diabolicus has composed with glucosamine and glucuronic acid (Arias et al., 2003).
Interactions between Oral Bacteria and Antibacterial Polymer-Based Restorative Materials
Published in Mary Anne S. Melo, Designing Bioactive Polymeric Materials for Restorative Dentistry, 2020
Fernando L. Esteban Florez, Sharukh S. Khajotia
In general terms, bacteria can only exist as planktonic or biofilm populations.[52] Microbial adhesion is considered as the cornerstone step in the process of colonization of oral surfaces (biotic and abiotic),[53] which allows for the establishment and growth of oral biofilms. Figure 4.3 shows a schematic drawing of the diverse phases of oral biofilm formation. These firmly attached and highly organized (layered-stratified) communities of microorganisms are typically found embedded in a matrix of extracellular polymeric substances (EPS)[52,54,55] composed of exopolysaccharides of both bacterial and human origin. The deposition of EPS is currently regarded as a universal survival strategy among numerous bacteria[56]. EPS provides the necessary scaffolding for biofilm growth,[57] and also acts as a biologically active layer that offers protection against external aggressors such as antibiotics,[58] disinfectants,[59] and dynamic environments.[60] This matrix also serves as a reservoir for key molecules, enzymes, and nutrients that are necessary for the maintenance of cells’ viability in conditions of nutrient deficiency.[61]
Bioprocess Parameters of Production of Cyanobacterial Exopolysaccharide
Published in Gokare A. Ravishankar, Ranga Rao Ambati, Handbook of Algal Technologies and Phytochemicals, 2019
Onkar Nath Tiwari, Sagnik Chakraborty, Indrama Devi, Abhijit Mondal, Biswanath Bhunia, Shen Boxiong
The exopolysaccharides from microalgae are gaining importance as sources of bioactive molecules of therapeutic importance. Several commercially available exopolysaccharides are obtained from cyanobacterial sources. Development of biotechnological processes for the production of biomass and downstream processing for the production of high-quality EPS products is being considered. However the process innovation is centric to the type of organism and conditions favoring the production of biomass and EPS. Accordingly the innovative interventions are being adopted for maximizing the yield for commercial feasibility.
Algal extracellular polymeric substances (algal-EPS) for mitigating the combined toxic effects of polystyrene nanoplastics and nano-TiO2 in Chlorella sp.
Published in Nanotoxicology, 2023
Lokeshwari Natarajan, M. Annie Jenifer, Willie J. G. M. Peijnenburg, Amitava Mukherjee
One of the critical gaps in the current ecotoxicological studies of nanomaterials lies in ignoring the role of naturally occurring biopolymers in modulating their physico-chemical as well as biological interactions. Extracellular Polymeric Substances (EPS) areone such natural biopolymer that often functions as a barrier to pollutants. EPS constitutes a key component of microalgae. Algae produce EPS for a variety of reasons, including (a) secure attachment and improvement of the local environment, and (b) as a metabolic waste. Notably, EPS secretion boosts cell survival, metabolic efficacy, and adaptability (Decho and Gutierrez 2017). These biopolymers can easily adsorb to nanomaterials in the aquatic environment, modulating their bioactivity, cytotoxicity, and physiological features (Alimi et al. 2018). This phenomenon is often referred to as eco-corona formation, the effects of which need to be considered while formulating an experimental design for nano-ecotoxicity studies in aquatic organisms.
Biofouling control of membrane distillation for seawater desalination: Effect of air-backwash and chemical cleaning on biofouling formation
Published in Biofouling, 2022
Ardiyan Harimawan, Vita Wonoputri, Jonathan Ariel, Helen Julian
Among all fouling types, biofouling do not receive much attention as the high temperature and high salt concentration in MD should inhibit the microorganism growth (Gryta 2002). However, the thermophilic bacteria were mentioned as the great concern on MD as the biofouling may reduce the flux and induce pore wetting (Bogler and Bar-Zeev 2018). The temperature on the membrane surface is not as high as in the bulk feed solution due to the temperature polarization (Julian et al. 2018), making membrane surface more ideal for biofilm formation. In addition, the use of renewable heat source or low-grade heat in MD leads to moderate feed temperature (Mericq et al. 2011; Andrés-Mañas et al. 2020) which are more suitable for the growth. Biofouling is started by the deposition of microorganisms on the membrane surface, which excrete extracellular polymeric substances (EPS) and form the biofilm (Costa et al. 2021). The EPS acts as the nutrient source, provides mechanical stability and water retention, allows communication between microorganism cells, and most importantly provides protective barrier for the microorganisms (Liu et al. 2020). The control of biofouling is challenging due to the protective nature of the EPS, and as a single microorganism can multiply and initiate the formation of the biofilm (Bogler and Bar-Zeev 2018).
Hurdle technology based on the use of microencapsulated pepsin, trypsin and carvacrol to eradicate Pseudomonas aeruginosa and Enterococcus faecalis biofilms
Published in Biofouling, 2022
Samah Mechmechani, Adem Gharsallaoui, Khaled El Omari, Alexandre Fadel, Monzer Hamze, Nour-Eddine Chihib
Bacterial cells in biofilms secrete extracellular polymeric substances (EPS), consisting mainly of polysaccharides, proteins, DNA, and lipids. They form a viscous film that encloses the bacterial cells (Flemming and Wingender 2010; Simões et al. 2010). The EPS matrix is structurally and functionally complex, which plays a major role in biofilm formation, survival, and development. It provides not only a barrier of protection against external stresses, but also a nutrient and enzyme source, and an intercellular connection (Pinto et al. 2020). Furthermore, the EPS matrix ensures the high antimicrobial resistance of biofilms (Pinto et al. 2020). Consequently, a new strategy for the efficient inactivation of bacterial cells in biofilms is needed. Approaches using enzymes that degrade the EPS matrix to remove biofilms have already been investigated (Kim et al. 2013). Many studies have highlighted the destructive and destabilizing power of protease-based enzymes when used against several bacterial biofilms (Fagerlund et al. 2016; Mohamed et al. 2018; Lim et al. 2019; Jee et al. 2020; Baidamshina et al. 2021).