Role of Exopolysaccharides of Pseudomonas in Heavy Metal Removal and Other Remediation Strategies

Abstract

Pseudomonas biofilms have been studied intensively for several decades and research outcomes have been successfully implemented in various medical and agricultural applications. Research on biofilm synthesis and composition has also overlapped with the objectives of environmental sciences, since biofilm components show exceptional physicochemical properties applicable to remediation techniques. Especially, exopolysaccharides (ExPs) have been at the center of scientific interest, indicating their potential in solving the environmental issues of heavy metal land and water contamination via sorptive interactions and flocculation. Since exposure to heavy metal via contaminated water or soil poses an imminent risk to the environment and human health, ExPs provide an interesting and viable solution to this issue, alongside other effective and green remedial techniques (e.g., phytostabilization, implementation of biosolids, and biosorption using agricultural wastes) aiming to restore contaminated sites to their natural, pollution-free state, or to ameliorate the negative impact of heavy metals on the environment. Thus, we discuss the plausible role and performance of Pseudomonas ExPs in remediation techniques, aiming to provide the relevant available and comprehensive information on ExPs’ biosynthesis and their usage in heavy metal remediation or other environmental applications, such as wastewater treatment via bioflocculation and soil remediation.

Impact of Vanadium–Titanium–Magnetite Mining Activities on Endophytic Bacterial Communities and Functions in the Root Systems of Local Plants

“…It has been shown that Pseudomonas can reduce highly toxic pentavalent V to less toxic tetravalent V under certain conditions, thereby reducing its toxicity [67]. At the same time, some studies have shown that Pseudomonas has a certain resistance to heavy metals and is widely used in heavy metal remediation [68][69][70][71]. Additionally, Actinobacteria and Firmicutes were dominant among the root endophytes in these samples, which could be attributed to their high tolerance to heavy metals.…”

Beneficial Interactive Effects Provided by an Arbuscular Mycorrhizal Fungi and Yeast on the Growth of Oenothera picensis Established on Cu Mine Tailings

“…On the yeast front, the presence of exopolysaccharides (EPS) may influence the soil-root interface, thereby reducing the availability of Cu. The intricate role of microbial EPS production in enhancing soil aggregation, particularly under challenging conditions such as salinity and drought, has been well documented [59][60][61]. Recent studies have further underscored the significant biotechnological potential of EPS, highlighting its efficacy in both the sequestration and remediation of heavy metals [50,62,63].…”

Testing plant growth promoting microorganisms in the field - a proposal for standards

“…• Phytohormonal plant growth stimulation, N 2fixation and improved nutrient acquisition (Singh et al, 2023) • Solubilization of P and other sparingly soluble nutrients (Barin et al, 2022) • Promotion of mycorrhization (Viollet et al, 2017) and legume nodulation (Soussou et al, 2017) • Soil aggregation (Sandhya and Ali 2015) and metal detoxification (Balıḱováet al, 2022) by release of exopolysaccharides…”