Responses of Periphyton Microbial Growth, Activity, and Pollutant Removal Efficiency to Cu Exposure

Abstract

Periphyton is an effective matrix for the removal of pollutants in wastewater and has been considered a promising method of bioremediation. However, it still needs to be verified whether periphyton can maintain microbial activity and pollutant removal efficiency when dealing with the influence with complex components, and the underlying mechanisms of periphyton need to be revealed further. Herein, this study investigated the microbial growth, activity and functional responses of periphyton after removal of Cu from wastewater. Results showed that the cultivated periphyton was dominated by filamentous algae, and high Cu removal efficiencies by periphyton were obtained after 108 h treatments. Although 2 mg/L Cu2+ changed the microalgal growth (decreasing the contents of total chlorophyll-a (Chla), the carbon source utilization and microbial metabolic activity in periphyton were not significantly affected and even increased by 2 mg/L Cu2+. Moreover, chemical oxygen demand (COD) removal rates were sustained after 0.5 and 2 mg/L Cu2+ treatments. Our work showed that periphyton had strong tolerance and resistance on Cu stress and is environmentally friendly in dealing with wastewater containing heavy metals, as the microbial functions in pollutant removal could be maintained.

Bioremediation: The Eco-Friendly Solution to the Hazardous Problem of Environmental Pollution

“…De Lorenzo (2008) provides a newer approach of bioremediation with the help of algal species. Periphytons inhabit the surface waters and are an important factor in determining the primary productivity of aquatic ecosystem (Zhong et al, 2020). The components of periphyton are algae, diatoms, fungi, bacteria, protozoa as well as small multicellular animals, and organic detritus (Wu et al, 2014).…”

Removal of Phosphorus and Cadmium from Wastewaters by Periphytic Biofilm

“…Additionally, Lu et al (2020) observed that periphytic biofilms significantly reduce Cd accumulation in rice, with a Cd adsorption rate of 390 pmol cm −2 s −1 [10]. Furthermore, when applied in wastewater treatment, periphytic biofilms have exhibited a high tolerance to Cu concentrations exceeding 2 mg L −1 [11]. By absorbing and accumulating Cd and Pi, periphytic biofilms effectively remove these contaminants from the water, reducing their availability to other organisms [12].…”