Journal of Hazardous Materials 334 (2017) 201–211 Contents lists available at ScienceDirect Journal of Hazardous Materials journal homepage: www.elsevier.com/locate/jhazmat Phenol remediation by peroxidase from an invasive mesquite: Turning an environmental wound into wisdom Savita Singh, Ruchi Mishra, Radhey Shyam Sharma, Vandana Mishra ∗ Bioresources and Environmental Biotechnology, Laboratory, Department of Environmental Studies, University of Delhi, Delhi-110 007, India h i g h l i g h t s • Peroxidase from invasive mesquite (MPx), for phenolic removal is reported. • 0.3U/ml MPx removes >92% of phenol, 2,4-dichlorophenol & 4-chlorphenol within 30 min. • MPx removes phenolics more effi- ciently than HRP at wide pH and temperature range. • MPx removes phenols & retains resid- ual activity, at high phenol levels or without PEG. • MPx reduces phenolic toxicity and enhances plant growth. g r a p h i c a l a b s t r a c t a r t i c l e i n f o Article history: Received 17 February 2017 Received in revised form 1 April 2017 Accepted 3 April 2017 Available online 4 April 2017 Keywords: Peroxidase Phenol Invasive species Remediation Mesquite Water pollution a b s t r a c t The present study examines mesquite (Prosopis juliflora), an invasive species, to yield peroxidase that may reduce hazards of phenolics to living organisms. As low as 0.3U of low-purity mesquite peroxidase (MPx) efficiently remove phenol and chlorophenols (90–92%) compared with Horseradish peroxidase (HRP) (40–60%). MPx shows a very high removal efficiency (40–50%) at a wide range of pH (2–9) and temperature (20–80 ◦ C), as opposed to HRP (15–20%). At a high-level of the substrate (2.4 mM) and without the addition of PEG, MPx maintains a significant phenolic removal (60– ≥ 92%) and residual activity (∼25%). It proves the superiority of MPx over HRP, which showed insignificant removal (10–12%) under similar conditions, and no residual activity even with PEG addition. The root elongation and plant growth bioassays confirm phenolic detoxification by MPx. Readily availability of mesquite across the countries and easy preparation of MPx from leaves make this tree as a sustainable source for a low-technological solution for phenol remediation. This study is the first step towards converting a biological wound of invasive species into wisdom and strength for protecting the environment from phenol pollution. © 2017 Elsevier B.V. All rights reserved. ∗ Corresponding author. E-mail addresses: mistletoe h@hotmail.com, vmishra@es.du.ac.in (V. Mishra). 1. Introduction Phenols are essential for industrial growth but deteriorate the quality of environment [1]. Annual production of phenols is ∼10 http://dx.doi.org/10.1016/j.jhazmat.2017.04.007 0304-3894/© 2017 Elsevier B.V. All rights reserved.