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This study aimed to assess the heavy metals accumulation patterns by some native plants such as Achyranthus aspera L., Amaranthus viridis, Basella alba L., Sesbania bispinosa, Pedalium murex L., and Momordica doica, which have been traditionally employed for medicinal and food purposes. The plants were grown on complex distillery waste containing a mixture of organometallic compounds. Results revealed bioaccumulation of Mn, Cd, Fe, Cr, Cu, As, Se, Mo, and Co in their roots, shoots, and leaves in levels higher than the surrounding sludge. A. aspera was noted as root accumulator for Mn (16.95 mg kg−1), Zn (30.12 mg kg−1), Fe (240.40 mg kg−1), Co (3.19 mg kg−1), while Se (4.07 mg kg−1), Mo (4.36 mg kg−1), was accumulated selectively in the shoot of the plant. Similarly, S. bispinosa, P. murex, and M. doica were found as root accumulators for Mn, Fe, and Ni. A. viridis accumulated Cd, Zn, and Cu in the shoot and leaves of the plant. The high bioconcentration factors (BCF) and translocation factors (TF) observed in these native plants (>1) suggested their tendency to hyperaccumulate heavy metals. The findings highlighted that these plants as a potential metal accumulator may pose health hazards and deteriorate the medicinal property if grown on such wastes.

Complex wastewater discharge from alcohol distilleries is one of the major sources of water and soil pollution, and the degradation of this effluent is a very challenging task. Distillery wastewater retains a high content of heavy metals as well as inorganic and organic compounds, which are difficult to remove due to their solubility in water or the presence of persistent and recalcitrant compounds. In recent decades, advanced oxidation processes (AOPs) have constituted important, efficient, promising, catalytic, and environmentally friendly treatment technology designed for the remediation of recalcitrant pollutants from industrial wastewaters. AOPs include ozonation, ultraviolet irradiation-based processes, Fenton oxidation, photo-Fenton oxidation, electrochemical remediation, sonolysis, photocatalytic technology, and various combinations of these technologies. This chapter delineates the advanced oxidation processes currently used for the remediation of untreated and partially treated distillery wastewater; controversial issues in pollutant degradation mechanisms are also discussed. Further, the principles, chemical performances, reaction mechanisms, and pros and cons of advanced oxidation processes in the degradation of some organic compounds of distillery wastewater are discussed. The authors also discuss issues associated with practical wastewater treatment and offer suggestions for the direction for future research.

The adaptation of any microorganism is morphological or biochemical changes required to survive in their ecological niches. This indicates the evolutionary process of bacterial communities, where the individual organism becomes better suited to live in its habitat. The bacterial communities have a broad range of adaptations due to their unique cell membrane properties and versatile nutritional behavior. It may be thermophiles, psychrophiles, acidophiles, halophiles, alkalophiles, and barophiles. To maintain the variable environmental conditions bacterial cell membrane protein modification plays a crucial role in controlling their function. The genome sequence of various psychrophiles revealed the function of the cell membrane with an increased proportion of polyunsaturated and branched fatty acids to increase the fluidity at low temperature and the presence of cold shock proteins are also believed to increase translational efficiency by destabilizing secondary structure of mRNA. The plant strategies for growth and phytoremediation at the polluted site involved various biochemical mechanisms for the amelioration of environmental pollutants. The mechanism of plant strategies is regulated through the production of glutathione, phytochelatins, metallothioneins, and various organic acids. Therefore the plant may adopt phytoextraction, phytostabilization, phytovolatilization, or rhizofiltration strategies based on the nature of pollutants and plant species. The phytoextraction process is mediated by the combined action of bacteria and plants due to secretion of some organic acids from plant and bacteria facilitating plant growth and transpiration mechanism. Consequently, various heavy metals are accumulated in the plant from complex organometallic wastes. The siderophores production for nutrient availability to plant is also a unique strategy of stress environment as a result of plant and bacterial interaction.

Environmental contamination (soil, water, and air) due to rampant industrialization, anthropogenic activities is a pertinacious problem and continues to be a burden to human and animal health in some parts of the world. Microbial communities are complex biological assemblies and play an integral and often unique role in ecosystem functions, whose study has been difficult for a long time because a large fraction of the species is unknown. Understanding the structure and composition of complex microbial communities and their responses to environmental perturbations, such as toxic contamination, climate change, and land-use changes, is critical for prediction, maintenance, and restoration of desirable ecosystem functions. Effective 16S rRNA genes based unbiased high-throughput “omics” approaches including metagenomics, metatranscriptomics, metaproteomics, metabolomics, interactomics, and fluxomics have been developed and applied for analyzing detailed knowledge of microbial community structure and function and quantitative measurements of various biological molecules in a high-throughput manner, thus allowing a better determination of their variation between different biological states on a genomic scale. In the present chapter, we discussed numerous advanced omics approaches that help to comprehend and explore the structural and functional aspects of the microbial communities in response to different environmental pollutants and presented some success stories by using these approaches.

Water, air, and soil pollution are becoming a major concern of the entire world due to rapid industrialization, economic growth, urbanization, increase in population, unsuitable and nonaffordable treatment technologies, and inadequate waste management practices. The safe disposal of solid waste mismanagement is a global issue in terms of environmental contamination and economic sustainability, which requires integrated assessments and holistic approaches for its solution. Landfills remain the main method of solid waste disposal and management in developed and developing countries. However, the major environmental challenges associated with the sustainable management of landfills are the surface and groundwater contamination and greenhouse gases and odor emissions. Phytocapping is an eco-friendly, cost-effective, and sustainable techniques to cover old landfill/dumpsites and to cap new landfills, with an objective to minimize leachate generation by reducing water infiltration into waste and to mitigate greenhouse emission and odor. The present chapter provides an overview of the role and mechanism of phytocapping technology for environmental cleanup.

Contamination of water and soil by toxic heavy metals and organic compounds, through natural and rapid industrial processes, due to its serious consequences on human health, agricultural crop production, and aquatic ecosystem has become a worldwide environmental problem. Therefore, the remediation of polluted soil and water has become an increasingly pressing issue worldwide. Conventional procedures to deal with the polluted environments are expensive, time-consuming and dependent on a complex group of techniques and equipment availability. Moreover, these techniques are not feasible at large due to generation of a huge amount of toxic sludge and other secondary pollutants. Alternatively, phytoremediation is an attractive, effective and, emerging eco-friendly technology that uses plants and their associated microorganisms to reduce and or degrade environmental pollutants from the contaminated sites. However, phytoremediation of numerous organic contaminants often proves not ideal because plants and their root-associated microorganisms only partially degrade these toxic compounds. In addition, the presence of toxic compounds in contaminated matrices can also affect the overall system performances by reducing the plant growth or by inhibiting the natural decay process. To tackle these issues, phytoaugmentation is considered to be a promising technology for the remediation of contaminated soil and wastewater as well. The present book chapter provides a view of the recent progress made toward the role of rhizospheric and endophytic bacteria in phytoaugmentation technology and presents their potential applications for cleanup of contaminated soil, domestic and industrial wastewater. Future, future prospects for phytoaugmentation have also been discussed for sustainable development.