Analysis of the Bioaugmentation Potential of Pseudomonas putida OR45a and Pseudomonas putida KB3 in the Sequencing Batch Reactors Fed with the Phenolic Landfill Leachate

Abstract

The treatment of landfill leachate could be challenging for the biological wastewater treatment systems due to its high toxicity and the presence of poorly biodegradable contaminants. In this study, the bioaugmentation technology was successfully applied in sequencing batch reactors (SBRs) fed with the phenolic landfill leachate by inoculation of the activated sludge (AS) with two phenol-degrading Pseudomonas putida OR45a and Pseudomonas putida KB3 strains. According to the results, the SBRs bioaugmented with Pseudomonas strains withstood the increasing concentrations of the leachate. This resulted in the higher removal efficiency of the chemical oxygen demand (COD) of 79–86%, ammonia nitrogen of 87–88% and phenolic compounds of 85–96% as compared to 45%, 64%, and 50% for the noninoculated SBR. Simultaneously, the bioaugmentation of the AS allowed to maintain the high enzymatic activity of dehydrogenases, nonspecific esterases, and catalase in this ecosystem, which contributed to the higher functional capacity of indigenous microorganisms than in the noninoculated AS. Herein, the stress level experienced by the microorganisms in the SBRs fed with the leachate computed based on the cellular ATP measurements showed that the abundance of exogenous Pseudomonas strains in the bioreactors contributed to the reduction in effluent toxicity, which was reflected by a decrease in the stress biomass index to 32–45% as compared to the nonbioaugmented AS (76%).

Sequencing batch reactor technology for landfill leachate treatment: A state-of-the-art review

“…Therefore, the unlawful disposal of solid waste at locations unprepared for landfilling could lead to unregulated leachate migration into the soil, surface water and even groundwater (Michalska, Gren, Zur, Wasilkowski, & Mrozik, 2019). Leachate considered as an exceptionally saline complex sewerage as well an unavoidable product of a sanitary landfill (Ganjian et al, 2018;Mousavi, Almasi, Kamari, Abdali, & Yosefi, 2015) can be defined as a reservoir with elevated concentrations of contaminants of emerging concern (Michalska, Pinski, Zur, & Mrozik, 2020). It is the liquid formed due to the percolation of precipitation through an open landfill or the cap of a finished site and infiltration of groundwater into the landfill through wastes and biochemical processes (Aziz, Aziz, & Yusoff, 2011a;Aziz, Aziz, Yusoff, & Bashir, 2011;Narayan, Zargham, Ngambia, & Riyanto, 2019).…”

Characterization of Biofilm Formation and Bacterial Resistance to Benzalkonium Chloride under Contrasting Cultivation Conditions

“…With regard to the measurement of metabolic activity in bacterial biofilms, a comparison of three assays, i.e., the crystal violet assay, ATP-luminescence, and FDA hydrolysis, showed that the crystal violet assay would be more appropriate for cases when the biofilm needs to be quantified irrespective of bacterial cell viability, and the FDA assay for cases when only the viable bacterial cells in the biofilm need to be quantified [46]. The use of DHA activity as a valuable criterion to detect the response of E. coli, P. putida, and S. epidermidis to the changing conditions/growth phase has been reported earlier [47][48][49]. The inhibition of DHA activity in pure Staphylococcus and Pseudomonas species has been used for assessing the antimicrobial effect of plant extracts [50].…”

Microbial Action in Wastewater and Sludge

“…This Special Issue consists of five thematically related articles, focusing on various methods to increase the efficiency of pollutant removal from wastewaters and landfill leachates. Among them, two articles present the bioaugmentation potential of selected bacterial strains to improve the aerobic treatment of phenolic landfill leachate [9,10]. The third article concerns the bioaugmentation of activated sludge with a bacterial consortium in order to remove selected non-steroidal anti-inflammatory drugs [11], the fourth is a mycoremediation study of old and intermediate landfill leachates [12], and the final review article indicates fungal biosorption as an eco-friendly, economical, and effective method for the removal of harmful pollutants from wastewater [13].…”

“…In another work by Michalska et al [10], a bioaugmentation approach was successfully applied in SBRs fed with phenolic landfill leachate by inoculation of AS with two newly isolated Pseudomonas putida OR45a and Pseudomonas putida KB3 strains. According to the results, the SBRs bioaugmented with Pseudomonas strains withstood increasing concentrations of the leachate, which was reflected in the high removal efficiency of the chemical oxygen demand (COD), ammonia nitrogen, and phenolic compounds as compared to the non-inoculated SBR.…”