Bioremediation and Phytoremediation: Theories and Perspectives

Introduction

Bioremediation is a waste management system (Sultana, Sanyal, & Hossain, 2015) toward solving various environmental problems (Rathoure, 2016). The objectives of a bioremediation process are to immobilize contaminants and to transform them into chemical products that do not pose a risk to human health and environment (Rathoure & Dhatwalia, 2016). Bioremediation options encompass diverse types of biotechnological mechanisms that lead to a target pollutant's mineralization, partial transformation, and humification (Basak & Dey, 2016). The combination of several remediation techniques are considered to improve the remediation results especially in the sites with complex contamination, as most traditional methods do not provide the acceptable solutions for the removal of wastes from soils (Shiekh, Bhat, Shah, & Ahanger, 2015).

Bioremediation is a method of removal of environmental pollutants and wastes from the environment by the utilization of microorganisms or microbes (Verma & Shukla, 2016). Rathoure (2016) indicated that bioremediation can be performed as the in situ treatment (i.e., treated at the site of pollution itself) or the ex situ treatment (i.e., taking them away from the site). The key to successful bioremediation is to trap up the occurring catabolic potential of microorganisms to effectively catalyze the transformations of environmental pollutants (Mohanta, Mohanta, & Mohanta, 2015). The application of bioremediation involves the manipulation of environmental parameters in such a way that they allow microbial growth and degradation to proceed at an adequately faster rate (Nanayakkara & Witharana, 2015).

Phytoremediation, a plant-based and cost-effective technology (Ha, Sakakibara, & Sano, 2009), is a treatment process that tackles environmental problems through the utilization of plants without the requirement to excavate the contaminant material (Dadrasnia, Emenike, & Ismail, 2015). Phytoremediation is a word formed from the Greek prefix “phyto” meaning plant, and the Latin suffix “remedium” meaning to clean or restore (Jagdale & Chabukswar, 2016). Phytotechnology, the application of science and engineering based on plants and associated microorganisms to analyze and solve problems, can offer the cost-effective alternative for the remediation of low-to-medium contamination of soils, sediments, solid wastes, and waters (Mench et al., 2010).

Heavy metals are one of the major ecological problems concerning human activities (Vigliotta, Matrella, Cicatelli, Guarino, & Castiglione, 2016). Phytoremediation is an emerging green technology that combines the disciplines of plant ecophysiology, soil chemistry, and microbiology to clean up heavy metal-polluted soils and waters (Mudhoo & Lin, 2012). Phytoremediation takes advantage of the unique and selective uptake capabilities of plant root systems, and applies these natural processes alongside the translocation, bioaccumulation, and contaminant degradation abilities of the entire plants (da Conceição Gomes, Hauser-Davis, de Souza, & Vitória, 2016).

This chapter focuses on the literature review through a thorough literature consolidation of bioremediation and phytoremediation. The extensive literature of bioremediation and phytoremediation provides a contribution to practitioners and researchers.