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Heavy Metals, Hydrocarbons, Radioactive Materials, Xenobiotics, Pesticides, Hazardous Chemicals, Explosives, Pharmaceutical Waste and Dyes Bioremediation
Published in Vivek Kumar, Rhizomicrobiome Dynamics in Bioremediation, 2021
Elżbieta Wołejko, Agata Jabłońska-Trypuć, Andrzej Butarewicz, Urszula Wydro
Drugs from the group of NSAID are the most frequently detected pain killers in surface water in an unchanged or slightly modified form. NSAIDs are detected in different areas of the environment in concentrations in the range of nanograms to micrograms per litre (Wu et al. 2012). Their high chemical stability causes problems with their elimination in sewage treatment plants, which may explain their presence in tap water with which they are unintentionally consumed by consumers. Bioremediation processes for the aforementioned group of drugs are a promising alternative to chemical methods of their removal, which in turn are often associated with the generation of large amounts of free radicals in the course of complex chemical reactions and generate high costs (Zhang et al. 2013). Among the microorganisms capable of decomposing and transforming NSAID, currently several species of fungi are mentioned, the most often being Penicillium sp., Trametes versicolor, Cunninghamella elegans, C. echinulata, C. blakesleeana, Beauveria bassiana, Phanerochaete chrysosporium, Ph. sordida, Actinoplanes sp., Bjerkandera sp. R1, Bj. adusta, Irpex lacteus, and Ganoderma lucidum (Wojcieszyńska et al. 2014, Rodarte-Morales et al. 2012). For instance naproxen, which is commonly found both in surface and groundwater and whose photolytic degradation generates photoproducts more toxic than a parent molecule, can be degraded by the fungus Trametes versicolor in a few hours process (Marco-Urrea et al. 2010). According to the literature data, other fungi species like Bjerkandera sp. R1 and Bj. adusta, require longer time, e.g. seven days, for complete naproxen removal (Rodarte st al. 2011). On the other hand, there are a few literature data regarding NSAID removal by different bacterial strains. Among them, Pseudomonas, Nocardia, Rhodococcus,Sphingomonas, Patulibacter and Stenotrophomonas were mentioned (Wu et al. 2012). For instance, paracetamol can be degraded by Delftia tsuruhatensis, Pseudomonas aeruginosa and Stenotrophomonas, which use drug as a sole carbon and energy source. Above mentioned strains use different mechanisms and a variety of enzymes in biodegradation process.
Genetic Variability of Klebsiella Variicola by RAPD-PCR Technique and Bioremoval of Pb2+ and Cd2+ from Simulated Contaminated Soils
Published in Soil and Sediment Contamination: An International Journal, 2022
Yetunde Mutiat Feruke-Bello, Gbolahan Babalola, Olu Odeyemi
Bioremediation of heavy metal by microorganisms makes use of bioaccumulation, biosorption, biomineralization and biotransformation [Ayangbenro and Babalola (2017)] ; therefore, scholar’s focus on immobilizing heavy metals in soils using microorganisms has increased. The strains of K. variicola and its mutant strains were Gram-negative, rod-shaped, non – spore-formers and exhibited multiple resistances to Pb, Cd, As and Ni. However, the resistance to Ni was observed to be lost in the mutant strains which could be attributed to the instability of the genes responsible for the Ni resistance or/ and means of preservation. Futhermore, Dabir et al. (2019) identified several heavy metal resistant bacterial strains from soil samples of a coal mine. The identities of each of the Klebsiella variicola strains were determined by 16S rDNA and their characteristics were observed to be the same as reported by Feruke-Bello, Babalola, and Odeyemi (2018). Several researchers have reported the isolation of bacteria with the capability to bioremediate Pb and Cd from contaminated environment. Liu et al. (2018) isolated a cadmium resistant bacterium named Delftia B9 sp. from cadmium contaminated soil from Zhuzhou, China. Lin et al. (2016) also isolated Delftia tsuruhatensis with resistance to cadmium and lead from contaminated rice field soil. Cadmium and lead resistant K. variicola was isolated in our previous research (Feruke-Bello, Babalola, and Odeyemi 2018), however, studies on isolation of heavy metal resistant K. variicola from metal-contaminated environment has rarely been reported.