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Anaerobically treated molasses-based distilleries spent wash is a major source of terrestrial and aquatic pollution due to the mixture of the various unknown organometallic compounds in discharged waste. The nature of pollutants present in effluent has to be characterized prior to the evaluation of their fate in the environment at various tropic levels. The absorption maxima (λmax) were obtained at 295 nm of pollutants present in spent wash which indicated that melanoidins are a major colorant along with other organic compounds. Abundantly identified compounds with GC–MS in effluent were found: 1,2,4,5-tetrahydro-2-methyl-3H-2-benzazepine-3-one, 6-(trifluoromethyl)-1H-imidazole [4,5-c] pyridine, 4,6-di-t-butyl-1H, 3H-thieno[3,4-c] thiophene, butanoic acid, trimethylsilyl ester, silane, (dodecyloxy)trimethylsilyl ester, 4-styryl [2,2] paracyclophane, 4-(p-cumylphenoxy) phthalonitrile, hexadecanoic acid, trimethylsilyl ester, butyl ester, and squalene. Some of these compounds are known with mutagenic and androgenic properties. The toxicity test of post-methanated distillery effluent (PMDE) showed direct toxic effects on catfish (Heteropneustes fossilis) even at 1% (v/v) concentration and caused degeneration of primary and secondary lamellae of the gill and the epithelial layer. Further, higher concentrations between 5 and 10% of PMDE showed loss of primary and secondary lamellae of gills, and liver catalase activity was also increased dramatically in H. fossilis, indicating the generation of oxidative free radicals. Similarly, inhibition of α-amylase activities in germinating Zea mays L. (Maize) seeds was also noted at 10% PMDE. This study confirmed the environmental toxicity of effluent with freshwater fish and Zea mays seeds.

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.

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.

Melanoidins are the randomly polymerized condensed anionic, non-enzymatic product of maillard reaction between amino and carbonyl group at elevated temperature. It occurs particularly during the food processing and wastewater released from distilleries and various fermented industries. Their synthesis is influenced by several factors because they alter the reaction path and change the product composition. Moreover, melanoidins have been known to be beneficial at low concentrations in food products due to their several properties in a biological system. But, when they are released into the environment at a high concentration from fermentation industries they cause a serious threat to land and aquatic ecosystem. This review encompasses the detailed chemical reaction of melanoidin synthesis and its functional properties to various substances present in nature with implications to its impact on the environment and their role in maintaining the nutritional and flavoring properties in food products.

This chapter discusses plant growth–promoting rhizobacteria (PGPR) and bioremediation of industrial waste. It is suggested that PGPR help plant growth not only via classically defined mechanisms (e.g., solubilization of insoluble nutrients, production of plant growth hormones, etc.) but also by mitigating the harmful effects of toxic pollutants grossly accumulated in the soil and groundwater. In the plant-microbial world, the association of PGPR with plants can be exploited for benefits not only for the associated organisms but also for the ecosystem. The eco-friendly approaches inspire a wide range of exploitation of beneficial agriculturally important bacteria and have led to improved nutrient uptake. They play a major role in improving soil fertility. They also play a very important role during remediation of bacterial-assisted phytoremediation of various pollutants present in industrial waste. Beneficial PGPR also play a key role in agricultural approaches through quorum sensing in their biofilm mode. The in vitro production of biofilm PGPR can be used to give increased crop yields and pollutants degradation through a range of plant growth mechanisms. The roots with attached microbial biofilms significantly contribute to soil fertility and bioremediation.