Enzymatic Treatment of Petrochemical Wastewater containing 2-Napthalene Sulfonated Polymers by Pleurotus ostreatus

Pleurotus ostreatus, using glucose as carbon source, is able to depolymerize a mixture of 2-naphthalene sulfonic acid polymers (NSAP), contained in a real petrochemical wastewater. On the contrary, its extracellular crude extracts, rich in laccases, are ineffective on NSAP degradation. Purified laccases and fungal extracellular extracts are able to depolymerize NSAP only in presence of specific synthetic or natural mediators. When P. ostreatus is grown on straw, the extracellular extracts are able to degrade the polymers, because they contain both high amount of laccases and natural mediators. Because of the negligible cost of the straw this process appears very promising for enzymatic bioremediation of wastewater from rubber industry

Biodegradation of 2-naphthalensulfonic acid polymers by white-rot fungi: Scale-up into non-sterile packed bed bioreactors

This paper presents a first scale up under non-sterile conditions of the biodegradation process of 2-naphthalensulfonic acid polymers (NSAP) contained in a petrochemical wastewater by two white-rot fungi (Bjerkandera adusta and Pleurotus ostreatus). The biodegradation experiment was conducted first in flasks and then in packed-bed bioreactors filled with inert and biodegradable carriers (straw), the latter acting as both physical support and carbon source. Reactor inoculated with P. ostreatus attached on straw worked under non-sterile conditions for three months showing 30 ± 5% NSAP degradation. Respirometric tests showed that the fungal treatment was also able to significantly increase the biodegradable fraction of the wastewater COD, which rose from 9% to 40%. It was observed that the fungal degradation of the straw in the bed releases non-biodegradable by-products. Taking into account this contribution to nbCOD, the combined treatment of fungi and activated sludge could theoretically be able to reduce the original COD by up to 73%