Characterization and biodegradation of paracetamol by Bacillus pumilus strain PYP2

AbstractAs we know the recent pandemic, coronavirus disease (COVID-19) due to SARS CoV-2 virus has led to an increase in the consumption of various drugs as medicines by the patients. Paracetamol (acetaminophen, APAP) act as an emerging contaminant classified among the class pharmaceutical and personal care pollutant (PPCP) and is detected in wastewater and sewage systems. The enrichment culture approach was used for the isolation APAP-degrading bacterium wastewater sample. Microscopic examination, biochemical and 16S rRNA sequence analysis showed that the isolate PYP-2 belongs to the Bacillus pumilus strain. Shake flask and batch culture degradation studies have shown that the strain can degrade APAP. Further, the response surface methodology (RSM) plot was used to know the best physical condition for biodegradation by optimization study. The optimum pH of 5.0, temperature of 30 °C, agitation speed of 146 rpm, and APAP 267 mg/L concentration were reported for PYP-2-based degradation. Bacterial biomass kinetic analysis was performed at the best physical condition, and the results showed that the specific growth rate (µ) was 713 mg/L. Oxalic acid, 2-isopropyl-5-methyl cyclohexanone, and phenothiazine were the intermediates of the APAP degradation pathway detected by the GC-MS chromatogram peaks. Therefore, this research has shown that Bacillus pumilus strain PYP-2 has the metabolic capacity to biodegrade APAP, providing new tools for bioremediation.Keywords: ParacetamolBacillus pumilus strain PYP-2biodegradation16S rRNA sequence analysisshake flask studywastewater AcknowledgmentsThe authors are thankful to Department of Biotechnology, Deenbandhu Chhotu Ram University of Science and Technology Murthal Sonipat Haryana India, for providing necessary facilities to conduct this study. The authors also acknowledge the sample analysis for FTIR at Central Instrumentation Laboratory (CIL), DCRUST Murthal Sonipat India, DNA sequencing at Eurofins Genomics India Pvt Ltd, Advanced Instrumentation Research Facility (AIRF), JNU New Delhi, India for GC-MS analysis. S. Chopra, also wishes to thank UGC, New Delhi India, for providing a research assistantship in the form RGNF fellowship. Authors are thankful to Editor/Reviewers for suggestions that has improved the the manuscript.Disclosure statementNo potential conflict of interest was reported by the authors.Author contributionsAll authors contributed to the study conception and design. The material preparation, data collection and analysis were performed by SC and DK. The first draft of the manuscript was written by SC and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript. DK supervised this research.Ethics approvalNot applicable.Data availability statementThe 16S rRNA gene sequence data of the paracetamol degrading Bacillus pumilus strain PYP-2 was deposited to National Centre of Biotechnology Information (NCBI) GenBank with accession number MN744329.Additional informationFundingThere is no external funding received to carry out this research. The authors wish to thank the Department of Biotechnology, DCRUST Murthal, Sonipat India, for providing the necessary facilities to carry out this research.