The use of surfactants in households and industries is inevitable and so is their discharge into the environment, especially into the water bodies as effluents. Being surface-active agents, their utilization is mostly seen in soaps, detergents, personal care products, emulsifiers, wetting agents, etc. Anionic surfactants are the most used class. These surfactants are responsible for the foam and froth in the water bodies and cause potential adverse effects to both biotic and abiotic components of the ecosystem. Surfactants are capable of penetrating the cell membrane and thus cause toxicity to living organisms. Accumulation of these compounds has been known to cause significant gill damage and loss of sight in fish. Alteration of physiological and biochemical parameters of water decreases the amount of dissolved oxygen and thus affecting the entire ecosystem. Microbes utilizing surfactants as substrates for energy form the basis of the biodegradation of these compounds. The main organisms for surfactant biodegradation, both in sewage and natural waters, are bacteria.Several Pseudomonas and Bacillus spp. have shown efficient degradation of anionic surfactants namely: sodium dodecyl sulphate (SDS), linear alkylbenzene sulphonate (LAS), sodium dodecylbenzenesulphonate (SDBS). Also, several microbial consortia constituting Alcaligenes spp., Citrobacter spp., etc. have shown efficacy in the degradation of surfactants. The biodegradation efficiency studies of these microbes/ microbial consortia would be of immense help in formulating better solutions for the bioremediation of surfactants and help to reduce their potential environmental hazards.

The increasing population density and industrialization are adversely affecting the environment globally. The contamination of the soil, agricultural lands, and water bodies with petroleum wastes and other hydrocarbon pollutants has become a serious environmental concern as perceived by the impacts on the aquatic and marine ecosystem. Various investigations have provided novel insights into the significant roles of microbial activities in the cleanup of hydrocarbon contaminants. However, the burden of these pollutants is expected to increase many folds in the next decade. Therefore, it is necessary to investigate and develop low-cost technologies rapidly, focusing on eco-sustainable development. An understanding of the details of biodegradation mechanisms paves the way for enhancing the efficiency of bioremediation technology. The current article reviews the applicability of various bioremediation processes, biodegradation pathways, and treatments, and the role of microbial activities in achieving efficient eco-sustainable bioremediation of hydrocarbon pollutants. It is envisaged that an integrated bioremediation approach, including biostimulation and bioaugmentation is preferably advocated for the cost-effective removal of toxic petroleum hydrocarbons and their derivatives.

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Anionic surfactants in the river, particularly downstream in Delhi, have created massive foam-like conditions which may be harmful to aquatic life and humans that come in contact. The present study focussed on the quantification of anionic surfactants, biological contaminants in terms of total bacterial count, total and faecal coliform bacteria and qualitative analysis of pathogenic bacteria from the samples acquired from different sites of Yamuna river. The concentration of anionic surfactants was observed to be between 0.42-3.89 mg L-1 at Okhla barrage, which was significantly high as compared to Wazirabad barrage and ITO bridge. The total bacterial count of Okhla barrage was observed more as compared to Wazirabad barrage and ITO Bridge ranging between 9.7 × 106 to 9.1 × 108 CFU/mL. The findings of total coliform bacteria were observed to be consistently high at Wazirabad barrage ranging between 1.3 × 103 to 9.0 × 104 MPN/100 mL. Qualitative analysis of pathogenic bacteria showed the presence of P. aeruginosa, Salmonella sp., E. coli and S. aureus. Based on the results obtained in the study, it was inferred that the water quality of Yamuna river at Wazirabad barrage, ITO Bridge and Okhla barrage was poor and thus requires regular monitoring and call for immediate effective mitigation strategies.Anionic surfactants in the river, particularly downstream in Delhi, have created massive foam-like conditions which may be harmful to aquatic life and humans that come in contact. The present study focussed on the quantification of anionic surfactants, biological contaminants in terms of total bacterial count, total and faecal coliform bacteria and qualitative analysis of pathogenic bacteria from the samples acquired from different sites of Yamuna river. The concentration of anionic surfactants was observed to be between 0.42-3.89 mg L-1 at Okhla barrage, which was significantly high as compared to Wazirabad barrage and ITO bridge. The total bacterial count of Okhla barrage was observed more as compared to Wazirabad barrage and ITO Bridge ranging between 9.7 × 106 to 9.1 × 108 CFU/mL. The findings of total coliform bacteria were observed to be consistently high at Wazirabad barrage ranging between 1.3 × 103 to 9.0 × 104 MPN/100 mL. Qualitative analysis of pathogenic bacteria showed the presence of P. aeruginosa, Salmonella sp., E. coli and S. aureus. Based on the results obtained in the study, it was inferred that the water quality of Yamuna river at Wazirabad barrage, ITO Bridge and Okhla barrage was poor and thus requires regular monitoring and call for immediate effective mitigation strategies.