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In the present investigation, a biocomposite, magnetic carbon nanodot immobilized Bacillus pseudomycoides MH229766 (MCdsIB) was developed and consequently characterized using SEM-EDX, FTIR, XRD, and VSM analyses to effectively biotreat hazardous Congo red (CR) dye present in water bodies. The adsorptive efficiency of MCdsIB for the detoxification of CR from wastewater was investigated both in batch and column schemes. Optimum batch parameters were found as pH 3, 50 mg L

Rapid growth in population, urbanization and industrialization has led to environmental pollution, which directly or indirectly has serious effects on all living beings. Providing and maintaining a clean environment by using sustainable, eco-friendly and cost-effective technologies is one of the difficult challenges of the twenty-first century. Thus, the need for a technology that not only cleans the environment but at the same time is cheap and eco-friendly cannot be avoided. Nanobioremediation is an advanced rapidly emerging technology in the field of nanotechnology for the removal of contaminants from the environment using biogenic nanoparticles. Herein, we review the biological synthesis of nanoparticles from plants, algae, yeast, fungi, bacteria and recent developments in the nanobioremediation technology for environmental clean-up. The technique of nanobioremediation is efficient, effective and proved to be a superior and non-toxic substitute to the available traditional methods.

Plastics are high-molecular-weight organic polymers acquired largely from different hydrocarbons and petroleum by-products. Globally, the production and consumption of plastics has increased over the years, because of their numerous applications in households and industries. However, a large number of these plastics are nonbiodegradable with only a few of them being biodegradable but at a very slow rate. Due to their substantial use, poor waste management, insufficiency in recycling, and improper disposal, plastics cause a serious threat to the environment and human health. This has led researchers to come up with novel and advanced techniques to manage plastic wastes and utilize biodegradable plastics in packaging. The present chapter highlights the different types of plastics, environmental pollution and health hazards from plastic waste, and the mechanisms involved in plastic degradation, with a special emphasis on biodegradation and its different types of mechanisms. The chapter also highlights the challenges and future prospects in plastic degradation.

Owing to rapid growth in urbanization, removal of environmental contaminants is the biggest challenge in the present scenario. Heavy metals are naturally occurring elements in the environment, but their negligent and indiscriminate discharge in the environment through anthropogenic and industrial activities has altered the ecosystem balance severely. The issue of heavy metal pollution thus seems to be a serious menace because of their persistent and recalcitrant nature. The conventional treatment technologies are effective to some extent, but the associated disparate drawbacks make the remediation process complex. Thus the development of nanomaterials has shown to possess distinct properties favoring their use in efficient remediation and more significantly in the ouster of heavy metals from the environment. This chapter presents varied nanomaterials such as metallic nanoparticles, nanowires, nanotubes, nanofibers, etc., with their advantages and mechanisms involved in the easy detection and removal of heavy metals and organic pollutants from the environment.

Antimicrobial resistance is a grave threat to human life. Currently used time-consuming antibiotic susceptibility test (AST) methods limit physicians in selecting proper antibiotics. Hence, we developed a rapid AST using electroanalysis with a 15 min assay time, called EAST, which is live-monitored by time-lapse microscopy video. The present work reports systematical electrochemical analysis and standardization of protocol for EAST measurement. The proposed EAST is successfully applied for Gram-positive

Microalgae are microscopic photosynthetic organisms that are found in both freshwater and marine environment. These are successfully used as food and feed supplements and are efficient producers of fine chemicals and biofuels. Microalgae are also an excellent source of bioactive compounds like vitamins, proteins, polyphenols, polyunsaturated fatty acids, or polysterols with antiviral, antibacterial, antifungal, and anticancer activities. Currently, the demand of these natural bioactive compounds is increasing as they impart health benefits when included and consumed in a functional food or in nutraceuticals. Thus, the utility of microalgae for the production of natural bioactive compounds should be explored at the commercial and industrial sector to harness the growing demands. The chapter gives the overview of different bioactive compounds produced by microalgae which have a wide range of application in different kinds of industries.

Increased population density and demands of urban environment together with industrialization has caused environmental pollution which ultimately has adverse effects on human health. Maintaining a clean environment by using a sustainable, eco-friendly and cost-effective technologies is one the arduous challenge of twenty-first century. Nanobioremediation is an advanced rapidly emerging technology for the removal of contaminants from the environment using biologically synthesized nanoparticles. These nanoparticles show unique physical, chemical and biochemical properties and thus have received considerable attention from researchers globally in different fields of environmental sciences including bioremediation. Biologically synthesized nanoparticles have been found to be significant in modifying and detoxifying pollutants which ruin the environment. Moreover, these also have the capability for extensive environmental cleanup at lower price and reduced toxic by-products. The present chapter summarizes the biological synthesis of nanoparticles from plants, algae, yeast, fungi and bacteria and recent developments in the nanobioremediation technology for environmental cleanup along with the future prospects. The technique of nanobioremediation is found to be efficient and economic and proved to be a superior and innocuous substitute to the available traditional methods providing a sustainable environment.

Bioremediation is traditionally carried out using ‘free’ bacterial cells; however, in recent years, utilization of ‘immobilized’ bacterial cells has gained attention as a promising technique due to multifarious benefits. This review collates a vast amount of existing literature on the myriad contaminants treated using immobilized bacteria. We also discuss various mechanistic aspects of using immobilized cells for environmental remediation applications, with special attention on cells encapsulated in hydrogels and their implementation in detoxifying harmful contaminants and environmental cleanup. We examine different methods/techniques for immobilizing viable bacterial cells in various supporting matrices, use of single- and multi-species bacterial communities, various growth substrates, and factors affecting the remediation process including mass transfer, kinetic processes and bioreactor configurations used in pilot and field-scale applications. The advantages and limitations associated with the use of immobilized bacteria in a bioreactor for contaminated water treatment are also discussed. From a sustainable futures perspective, resource recovery and retrieval of value-added products along with bioremediation could be an added benefit of the immobilized cell-based treatment system, making it a more cost-effective and viable treatment strategy as well as one that is amenable to the principles of circular economy.

Supplementation of consortium comprising of aboriginal bacterial species with high degradation capacity can significantly enhance the biodegradation process of the domestic wastewater. The present study examined the bioremediation of domestic wastewater using a novel bacterial consortium comprising of five autochthonous bacterial strains with high potential for reduction in BOD, COD and protein content to 89%, 55% and 86%, respectively after 24 h of incubation. HPLC and GC-MS analyses revealed that the chosen consortium had successfully degraded wide-ranging complex organic compounds, which is crucial in the decontamination of wastewater. Phytotoxicity assay of the effluent exhibited that the seeds of Vigna radiata showed better growth and germination when subjected to wastewater treated by novel bacterial consortium as compared to the seeds exposed to untreated wastewater. Further, raw and treated wastewater were assessed for their genotoxicity with comet assay which displayed the intensity of DNA damage in the Allium cepa root tip cells before and after exposure to treated effluent. It is evident from the demonstrated results that the formulated bacterial consortium can be used successfully in a small-scale wastewater treatment plant.

A new approach for easy synthesis of Bacillus pseudomycoides immobilized polyvinyl alcohol (PVA)/glutaraldehyde (GA) hydrogel for application in a wastewater treatment system is reported. Optimization studies revealed that GA/PVA mass ratio of 0.03 and acidic pH of 2 were required for hydrogel synthesis and eventually for bacterial cell immobilization. The synthesized crosslinked matrix possessed a pore size suitable for microbial cell entrapment while maintaining cell accessibility to external environment for bioremediation. Possible crosslinking and bacterial cell immobilization in the hydrogel were evidenced by FTIR, XRD, and SEM studies, respectively. Further, the extent of crosslinking of GA with PVA was investigated and confirmed by transmittance and permeability experiments. The viability and proliferation of hydrogel embedded cells (after 25 days) was confirmed by confocal fluorescence microscopy which also indicated that acidic pH of polymer solution did not affect the immobilized live cells. B. pseudomycoides immobilized hydrogel were demonstrated to be effective for treatment of municipal wastewater and reduced biochemical oxygen demand (BOD), chemical oxygen demand (COD), and protein content below the recommended levels. Overall, the results from this bench-scale work show that employing bacteria-embedded PVA/GA hydrogel for the treatment of municipal wastewater yield promising results which should be further explored in pilot/field-scale studies.

The biological approach for the synthesis of metallic nanoparticles provides an eco-friendly substitute to the conventional chemical and physical methods. Cell-mediated synthesis of silver nanoparticles using microorganisms are reported to be slow, hence, the present study demonstrates a rapid bio-reductive method by using a new and rare Bacillus species (Bacillus pseudomycoides MH229766) out of the two isolated Bacillus species from the domestic effluent. The synthesis of silver nanoparticle was confirmed by UV-Visible Spectroscopy, its morphology by Scanning Electron Microscopy (SEM), elemental profiling by Energy Dispersive X-ray analysis (EDX) and size by Dynamic Light Scattering (DLS). The bio-electrochemical evaluation was also done comprehending the capability of Bacillus pseudomycoides to synthesize silver nanoparticles. The green synthesized nanoparticle was effective in treating domestic wastewater, which was confirmed by ∼90% reduction in BOD and ∼60% reduction in COD after 5 days of application.

Dairy industry is one of the most polluting industries in India. Due to the elevated milk demand, the dairy industry in India has developed swiftly, leading to a large amount of waste discharge in the nearby water bodies. The waste water from dairy industry is characterized by high BOD, COD, organic and inorganic contents. Release of these waste waters into the water bodies without suitable remediation can cause serious environmental issue. Indian government has enforced very stern rules and regulations for the waste water discharge to safeguard the environment. Therefore, suitable methods are needed to meet the effluent discharge standards. This chapter thus discusses the various sources and characterization of dairy waste water, their impact on the environment and the conventional as well as the improved techniques for the treatment of dairy waste water.

Bacterial strain Bacillus pseudomycoides, isolated from domestic wastewater was used to decolorize azo dye Acid Black 24. Response Surface Methodology based on Box- Behnken model was used to optimize the conditions for maximum dye decolorization. High regression coefficient values (adjusted R2 = 0.9317 and predicted R2 = 0.8343) confirmed that the predicted values are in compliance with the experimental values implying the appropriateness of the employed polynomial regression model. The adequacy of the model was validated by different descriptive statistics viz. lack of fit, adequate precision, F and p values. 96.79% of dye decolorization was achieved at pH 7, temperature 37 °C and 40 mg L−1 dye concentration. The activities of oxido-reductive enzymes like lignin peroxidase, laccase and azoreductase were found to be induced during the dye decolorization process. The biodegradation of the dye was assessed by HPLC, FTIR and UV spectroscopy. Genotoxicity and phytotoxicity studies substantiated the nontoxic nature of the degraded dye.

The beverages industry faces growing scrutiny of responsible use and protection of the natural environment through conservation and sustainable practices. These industries cause high probability of polluting the environment by discharging untreated wastewater in to the soil and water which lead to agricultural loss and human health hazards. The aim of this study was to characterize various physiochemical parameters such as pH, temperature, TS, BOD, COD and DO etc. from effluent samples collected from four different beverage industries located in Delhi-NCR along with the biochemical characterization of isolated bacterial strains from effluent. Analysis of the collected samples states that the pH values were 4.57, 4.91, 5.17 and 5.11; Total Dissolved Solids were 1175 mg/l, 1210mg/l, 1270 mg/l and 1250 mg/l; total hardness was measured as 226, 223, 244 and 220 mg/l and alkalinity were 130, 138, 145 and 141 mg/l, respectively. Chloride test was found negative for effluent samples revealing the absence of chlorine molecule. Dissolved Oxygen were 3.3, 2.8, 3.1 and 3.2 mg/l, Biological Oxygen Demand were 211, 256, 237 and 272 mg/l where as Chemical Oxygen Demand was found 1067, 1098, 1078 and 1092 mg/l, respectively. Results suggested that pH values, DO, total hardness, alkalinity; BOD and COD were exceeded to the permissible standard limits. This study provides a detailed insight that beverage industries do produce waste linked problems and there is a high probability of polluting the environment by these industries as a result of discharge of untreated wastewater into the water body or soil that may lead to death of crops or reduction in crops yield, contamination of drinking water supplies and/or accumulation and dissemination of toxic chemicals that may further endanger ecosystems and threaten public health. It is hoped that waste water management practices being used in beverages and other food industries will benefit to sustain the natural environment.