Abstract
The use of antibiotics is increasing and they enter water untreated. These antibiotics tendency to bioaccumulate and contribute to bacterial resistance. This study is designed to explore and optimize the potential of resistant bacteria for the treatment of norfloxacin (NOR) antibiotic spiked wastewater. The Alcaligenes faecalis ABR-14 was isolated from wastewater and sludge samples and was identified using 16S rRNA sequencing (Macrogen Inc. Geumchen-gu, South Korea). The 1515 bp was submitted in NCBI Genbank and the accession number of ‘PV364597.1’ was obtained. The results demonstrated that Alcaligenes faecalis ABR-14 efficiently broke down NOR reaching 96% degradation at 100 mg/L in 10 days under ideal circumstances such as 35 °C, pH 6.5, sodium acetate, NH4Cl and 105 CFU/mL. Two significate parameters (pH and Nitrogen (N) source), one less-significant parameter (inoculum density) and 3 non-significant parameters (antibiotic concentration, temperature and Carbon (C) source) based on Central Composite Design (CCD) and Response Surface Methodology (RSM) were revealed. The Hanes plot gives straight line, where R2 is 0.99, Vmax = 200.21, Km = 133.4. The plot between experimental and predicted values represent the best fit of the values based on straightness (R2 = 0.91). ANOVA for CCD present the p value below 0.05 which represents the significance and critically important factors. This study is among the first highlights the potential application of Alcaligenes faecalis ABR-14 for norfloxacin biodegradation. The generation of non-toxic metabolites makes this eco-friendly and sustainable. The abilities of such resistant microbes can be utilized in future to develop NOR contaminated wastewater treatment plant.
Data availability
The data for 16sRNA and 1515 bp were submitted to NCBI Genbank under accession number of PV362284.1. Deposited data is available at the following https://www.ncbi.nlm.nih.gov/nuccore/PV362284.1. All data supporting the findings of this study are available within the paper in Tables and Figures.
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Acknowledgements
We are thankful to “Environmental Protection Department, Punjab, Pakistan” and “Irrigation Department, Government of the Punjab, Pakistan” for helping us in wastewater/sediment sampling and analysis. We are also thankful to “Office of Research Innovation and Commercialization, Government College University Lahore, Pakistan” for providing necessary funding and facilities.
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The authors are thankful to Government College University Lahore for providing financial support to carry out this research, vide letter No. 31/ORIC/24.
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A.A, M.F and A. R planned this research. A.A and A.K conducted this research. A. A, M. F and A. R, A. K and F. S analyse the data. All authors contributed in research paper writing.
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Ali, A., Farhan, M., Rehman, A.u. et al. Harnessing the potential of Alcaligenes faecalis for optimum biodegradation of norfloxacin spiked wastewater using response surface methodology. Sci Rep (2026). https://doi.org/10.1038/s41598-026-46734-0
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DOI: https://doi.org/10.1038/s41598-026-46734-0