A dualistic approach to investigate the remedial potential and edible property of Pleurotus ostreatus on hydrocarbon-contaminated soil

Abstract

Hydrocarbon soil contaminants are the major concern globally that causes an adverse impact on human health and reduces the functionality of ecosystem. Mycoremediation certainly has an edge over other bioremediation process in combating the targets most efficiently. This study attempts to investigate the potentials of an edible mushroom dualistically remediating the hydrocarbon-contaminated (HC) soil as well analyzing its impact on edibility. Many studies have been done over the past few decades, no attempts were made to analyze the presence or absence of toxicity sorption in edible organisms after remediation. HC soils from eight different petrol filling stations (Site A to H) of Coimbatore district were collected and analyzed for its physical and chemical properties. Based on physicochemical parameters, Site D1 that showed maximum total petroleum hydrocarbon (TPH) content (12,200 mg/ kg) was chosen for this study. Five experimental sets were prepared by mixing the lignocellulose substance with HC soil at different ratio (Set I–Set V). Among the experimental sets, P. ostreatus showed maximum hydrocarbon degradation efficiency and well-defined fruiting body formation, high biological efficiency (140%), moisture (90%), and crude protein (32%) in Set III trials. Kinetic studies on TPH degradation fitted to the first-order kinetic model revealed a higher degradation rate constant, k (0.097 day-1) and lower biodegradation half-life t1/2 (7 days). Fourier transform infrared spectrum of P. ostreatus after remediation showed the complete absence of peak that corresponds to petroleum hydrocarbon, thereby preliminarily confirms the possibility of safe consumption.