Effect of Pseudomonas moorei KB4 Cells' Immobilisation on Their Degradation Potential and Tolerance towards Paracetamol

Functional characterization of an efficient ibuprofen-mineralizing bacterial consortium

Ibuprofen (IBU) is a widely used non-steroidal anti-inflammatory drug (NSAID), which has attracted widespread attention due to its high frequency of environmental detection, non-degradability and potential ecological risks. However, little is known about the functional characterization of the highly efficient IBU-mineralizing consortium. In this study, an IBU-mineralizing consortium C6 was obtained by continuous enrichment of the original consortium C1 accumulated the metabolite of 2-Hydroxyibuprofen (2HIBU). Methylobacter, Pseudomonas, and Dokdonella spp. were significantly enriched in the consortium C6. Streptomyces sp. had a relative abundance of about 0.01 % in the consortium C1 but extremely low (< 0.001 %) in the consortium C6. Subsequently, two IBU degraders, Streptomyces sp. D218 and Pseudomonas sp. M20 with detection of 2HIBU or not, were isolated from the consortia C1 and C6, respectively. These results imply that the degradation of IBU in the consortia C1 and C6 may be mainly mediated by key players of Streptomyces and Pseudomonas, respectively. This study showed that the composition of the core functional strains of the bacterial community structure was changed by continuous enrichment, which affected the degradation process of IBU. These findings provide new insights into our understanding of the biotransformation process of NSAIDs and provide valuable strain resources for bioremediation.

Characterization and biodegradation of paracetamol by biomass of Bacillus licheniformis strain PPY-2 isolated from wastewater

Industrialization leads to the entry of diverse xenobiotic compounds into the environment. One such compound is paracetamol (APAP), which is emerging as a pharmaceutical and personal care pollutant (PPCP). In this study, the APAP degrading bacterium was isolated by enrichment culture method from the sewage sample. The microscopy, biochemical, and 16S rRNA gene sequence analyzed the isolate PPY-2, which belongs to Bacillus licheniformis, and GenBank assigned accession number MN744328. Physiological and batch culture degradation studies have indicated that the strain involved in the degradation of APAP. The optimum pH for degradation of the PPY-2 was 7.7, whereas the temperature was 25 °C, agitation speed was 142 rpm, and concentration of APAP was 621 mg/L reported, and the optimum temperatures were 42 °C and 32 °C, respectively. Biomass kinetic was studied at optimal physical conditions, which suggested that the specific growth rate (μ) was 721 mg/L. The GC-MS chromatogram peaks have detected metabolites, viz., oxalic acid, 2-isopropyl-5-methyl cyclohexanone, and phenothiazine. The study confirmed that Bacillus licheniformis strain PPY-2 exhibits metabolic potential to biodegradation APAP and can be further deployed in bioremediation.

Immobilization of Biomass Materials for Removal of Refractory Organic Pollutants from Wastewater

In the field of environmental science and engineering, microorganisms, enzymes and algae are promising biomass materials that can effectively degrade pollutants. However, problems such as poor environmental adaptability, recycling difficulties, and secondary pollution exist in the practical application of non-immobilized biomass materials. Biomass immobilization is a novel environmental remediation technology that can effectively solve these problems. Compared with non-immobilized biomass, immobilized biomass materials have the advantages of reusability and stability in terms of pH, temperature, handling, and storage. Many researchers have studied immobilization technology (i.e., methods, carriers, and biomass types) and its applications for removing refractory organic pollutants. Based on this, this paper reviews biomass immobilization technology, outlines the mechanisms and factors affecting the removal of refractory organic pollutants, and introduces the application of immobilized biomass materials as fillers for reactors in water purification. This review provides some practical references for the preparation and application of immobilized biomass materials and promotes further research and development to expand the application range of this material for water purification.

Draft Genomic Sequences of Pseudomonas moorei Strains Isolated from Wild Cranberry Bogs in Massachusetts

Pseudomonas moorei has been used to detoxify recalcitrant environmental contaminants from the pharmaceutical industry. Two P. moorei strains were isolated from soil in the pristine wild cranberry bogs of the Cape Cod National Seashore that putatively encode genes for degradation of 4- and 5-chlorosalicylates, acetaminophen, and diclofenac.

Immobilized Stenotrophomonas maltophilia KB2 in Naproxen Degradation

Immobilization is a commonly used method in response to the need to increase the resistance of microorganisms to the toxic effects of xenobiotics. In this study, a plant sponge from Luffa cylindrica was used as a carrier for the immobilization of the Stenotrophomonas maltophilia KB2 strain since such a carrier meets the criteria for high-quality carriers, i.e., low price and biodegradability. The optimal immobilization conditions were established as a temperature of 30 °C, pH 7.2, incubation time of 72 h, and an optical density of the culture of 1.4. The strain immobilized in such conditions was used for the biodegradation of naproxen, and an average rate of degradation of 3.8 µg/hour was obtained under cometabolic conditions with glucose. The obtained results indicate that a microbiological preparation based on immobilized cells on a luffa sponge can be used in bioremediation processes where it is necessary to remove the introduced carrier.

Stability of 28 typical prescription drugs in sewer systems and interaction with the biofilm bacterial community

Identifying the attenuation characteristics of drugs in sewage and sewers is one of the important factors to improve the accuracy of wastewater-based epidemiology (WBE) application. In this study, 28 drugs including antidepressants, cardiovascular drugs, antihistamines, anticonvulsants and some of their human metabolites were chosen as the targets to study the hydrolysis, adsorption, and biodegradation at different temperatures in sewage and sewers. The interaction between drugs degradation and community structure of biofilm was also investigated. In the simulated sewers, the removal percentages of 12 parent or drug metabolites are 0-20%, such as demethylvenlafaxine, fluvoxamine, etc., which are highly stable chemicals and suitable to be chosen as biomarkers for WBE back-calculation under appropriate circumstances. Fourteen drugs including venlafaxine and citalopram have removal percentages of 20-60%. While paroxetine and sertraline, with removal percentage of 100%, are the most unstable and cannot be used as biomarkers. Among the 28 drugs, there are 25 drugs that have a higher loss rate in the aerobic sewer than that in the anaerobic sewer in this study. During drug exposure in anaerobic biofilms, species abundance first decreased and then increased. Species abundance and diversity in aerobic biofilm generally showed a decreasing trend. In addition, Proteobacteria and Spirochaetota were the dominant phyla in both sewers.