Biodegradation of plasticizers by novel strains of bacteria isolated from plastic waste near Juhu Beach, Mumbai, India

Phthalic acid esters are pivotal plasticizers in various applications, including cosmetics, packaging materials, and medical devices. They have garnered significant attention from the scientific community due to their persistence in ecosystems. The multifaceted aspects of PAEs, encompassing leaching, transformation, and toxicity, underscore their prominence as primary components of anthropogenic waste. In this study, we conducted an extensive investigation to isolate and evaluate bacterial strains with the potential to degrade plasticizers from soil samples collected at JUHU Beach, Mumbai. The degradation capabilities of the isolates were meticulously assessed, and their characterization was performed using established microbiological protocols followed by Sanger dideoxy 16S rRNA sequencing. Four isolates demonstrating notable plasticizer degradation proficiency were subjected to in-depth examinations of their growth dynamics and tolerance thresholds. The biodegradation capabilities of these isolates were evaluated under varying pH, temperature, and plasticizer concentrations. Optimization of degradation rates was achieved through a central composite design experiment. Phenotypic characterization of the isolates was conducted through phylogenetic analysis. The isolates were identified as novel strains belonging to Brevibacillus brevis, Acinetobacter baumannii, Moraxella sp., and Halomonas sp. respectively. The novel isolates were submitted to GenBank with accession numbers OP984197, OQ690115, PP174910, and PP177540 respectively.