Bioremediation of MP-polluted Waters Using Bacteria Bacillus licheniformis, Lysinibacillus massiliensis, and Mixed Culture of Bacillus sp. and Delftia acidovorans

Abstract

Microplastic particles (MPs) are widely distributed pollutants in the environment. While a growing number of studies have shown that MPs are toxic to plant and animal life, systemic efforts to reduce their presence have been scarce. Low-density polyethylene (LDPE) and polystyrene (PS) are one of the most common among all plastic-forming MPs. In this study, pure bacterial strains, Bacillus licheniformis and Lysinibacillus <br /> massiliensis, and a mixed bacterial culture of Delftia acidovorans and Bacillus sp., were <br /> used for biodegradation of LDPE and PS microplastics. Biodegradation of MP-PS and <br /> MP-LDPE of particle size 300 – 500 μm was carried out under batch operating conditions at a temperature of 25 ± 2 °C, pH values of 7.15, and 160 rpm during 22 days. The <br /> obtained results showed that mixed bacterial cultures degraded MP-LDPE and MP-PS <br /> better than pure bacterial cultures, and the biodegradation efficiency was higher for MP-LDPE than for MP-PS, as indicated by greater reduction in peak intensity and spectral <br /> deformation, higher colony forming unit (CFU), and inorganic carbon (IC) values.

Optimization of Polystyrene Biodegradation by Bacillus cereus and Pseudomonas alcaligenes Using Full Factorial Design

“…These changes were also consistent with the changes in CFU of Pseudomonas alcaligenes during the 30-day biodegradation of PS. However, TOC and TIC concentrations in the blank (BP) also increased, indicating the lysis of bacterial cells [ 27 , 52 ]. Compared to BP, TOC and TIC values were higher in samples with MP-PS particles, indicating the utilization of MP-PS by bacteria.…”

“…The most used bacteria for PS degradation are genera Bacillus [ 5 , 14 , 26 , 27 ], Pseudomonas [ 26 ], Paenibacillus [ 28 ], and Rhodococcus [ 29 , 30 ], while Aspergillus [ 5 ] and Curvularia [ 31 ] are the most investigated genera of fungi. Asmita et al [ 5 ] reported PS weight loss of 20.0 and 5.0% by Bacillus subtilis and Pseudomonas aeruginosa , respectively, which were cultured in nutrient broth.…”

Removing microplastics from aquatic environments: A critical review

“…6.4% [ 156 ] B. cereus and B. gottheilii Mangrove sediment The bacterial isolates possess functional groups that can attach to the microplastic surfaces PE powder (white/75 μm, 0.94 g mL −1 ), PP granules (white/spherical, 0.9 g mL −1 ), PS granules (white/spherical, 1.59 g mL −1 ), PET granules (granular/milky white, 1.68 g mL −1 ) After 40 days, the percentage weight loss of PE, PET, and PS by B. cereus was 1.6%, 6.6%, and 7.4%, respectively; the percentage weight loss of PE, PET, PP, and PS by B. gottheilii was 6.6%, 3.0%, 3.6%, and 5.8%, respectively [ 157 ] Zalerion maritimum Maritime coastal waters Zalerion maritimum used PE-MPs as a nutrient source PE−MPs (250–1000 μm) The weight loss of PE−MPs in 14 days was 56.7 ± 2.9% [ 158 ] Pure bacterial strains, Bacillus licheniformis and Lysinibacillus massiliensis , and a mixed bacterial Culture of Delftia acidovorans and Bacillus sp. Activated sludge and sediment There was a release of additives from the surface of LDPE−MPs and PS−MPs and disruption of its structure LDPE, PS−MPs (300–500 μm) N/A [ 159 ] Aspergillus flavus named PEDX3 The guts of wax moth Galleria mellonella Two LMCOs that isolated from Aspergillus flavus were considered as the potential PE-degrading enzymes after preliminary screen LDPE with density of 0.921 g cm −3 , HDPE with density of 0.955 g cm −3 (＜200 μm) The mass loss percentage (Δm/m0) was 3.9025 ± 1.18% after 28 days [ 161 ] Greater wax moth (Galleria mellonella) larvae N/A Through the styrene oxide–phenylacetaldehyde, and 4-methylphenol–4-hydroxybenzaldehyde–4-hydroxybenzoate metabolic pathways PS microbead suspensions with and without red fluorescence labeling (25 μm, provided as mono-spheres suspended in distilled water at a concentration of 2.5% w/v) ...…”

“…LDPE−MPs and PS−MPs were reported to be degraded by Bacillus licheniformis , Lysinibacillus massiliensis , and mixed cultures of Delftia acidovorans and Bacillus sp. [ 159 ]. Hyperthermophilic bacteria in h TC accelerated PS−MPs biodegradation through excellent bio-oxidation performance of Thermus , Bacillus , and Geobacillus , which were the dominant bacteria responsible for the highly efficient biodegradation [ 109 ].…”

Development of plastic-degrading microbial consortia by induced selection in microcosms

“…As a consequence, its use has increased exponentially reaching 370 million tons per year in Europe in 2016 and forecasting 800 million tons per year by 2040 ( Lebreton and Rady, 2019 ; Wang et al, 2019 ). This high production results in the generation of large quantities of plastic waste that is highly resistant to biodegradation, mainly due to its molecular structure, which is made up of long carbon chains ( Kučić Grgić et al, 2021 ; Ragusa et al, 2021 ). Pollution by microplastics and film plastics is increasingly problematic due to their small size, which allows their easy ingestion by a wide range of organisms and their consequent accumulation in food chains ( Zurier and Goddard, 2021 ).…”