Mycoremediation of Atrazine in a Contaminated Clay-Loam Soil and its Adsorption-Desorption Kinetic Parameters

Abstract

Clean-up of contaminated soils with atrazine is an ecological responsibility. The objectives of this study are to evaluate atrazine degradation in a clay-loam soil microcosm using fungal enzyme extracts from Trametes maxima and its co-culture with Paecilomyces carneus and to determine the kinetic parameters of the adsorption-desorption of atrazine in soil. Fungal co-culture extract (T. maxima-P. carneus) and monoculture (T. maxima) were able to degrade 100% of atrazine. However, we observed variation in atrazine degradation over the course of the evaluated time period, which suggests that an adsorption-desorption process is occurring in the soil. Adsorption-desorption kinetic parameters of the Freundlich model revealed that the studied soil has a significant capacity to adsorb atrazine (K-F = 8.2148; r(2) = 0.992 and P-value < 0.0001), while according to the desorption parameters (K-F = 5.4992; r(2) = 0.245 and P-value = 0.036) and hysteresis index (H = 0.573), the soil does not desorb atrazine at the same rate. Fungal enzyme extracts from a monoculture and co culture of T. maxima were able to degrade atrazine in a short time period (< 12 h). The ability of the contaminated soils to adsorb and desorb atrazine should be taken into account in mycoremediation systems.