About this Research Topic
Coloured textile products are an indispensable amenity of the modern human society. The coloration of textiles is achieved by application of various classes of aromatic dye compounds (such as disperse, direct, reactive, vat, etc.) consisting of diverse xenobiotic chemical structures (such as azo, nitroso, anthraquinone, sulpho, acidic, basic, mordant, etc.) and therefore are recalcitrant to photolysis, fading and microbial degradation. The textile and allied industries generate large volumes of toxic dye bearing hazardous wastewaters mainly due to inefficiencies in the water demanding textile dyeing processes. Textile dye wastewaters have a complex composition, for example in addition to unbound dyes they contain various auxiliary chemicals such as soda-ash, fastening and binding agents and other synthetic compounds. The characteristics of textile wastewater varys depending on its constituent pollutants, typically textile wasterwaters are highly coloured and have higher chemical oxygen demand (COD), total dissolved solids (TDS) and varying degrees of salinity, alkalinity or acidity and biochemical oxygen demand (BOD). Many types of textile dye wastewaters are known to have the BOD/COD ratio below 0.3 and therefore are resistant to biodegradation. Textile wastewaters also contain intermediates of partial dye degradation products (such as aromatic amines) which alongwith other pollutants exert extremely bio-toxic, mutagenic and carcinogenic effects. Direct release of untreated textile wastewaters imparts intense colour to pristine water resources and inhibits various ecosystem processes causing significant pollution of the water and soil habitats across the globe.
Microbial bioremediation of textile wastewaters is sought after as an eco-friendly and sustainable alternative to the conventional treatment methods. Given the adaptive nature of microorganisms to xenobiotic pollutants, a large number of microorganisms, including bacteria, fungi, yeasts, algae or microbial consortia and microbial communities have been tested for the biodecolourization, biodegradation and mineralization of various types of textile dyes and wastewaters in recent years. Promising alternative bioremediation strategies including sequential microbial treatment approaches, biofilm and membrane bioreactors, hybrid/integrated bioreactors, microbial fuel cells (MFCs), plant-microbial fuel cells (P-MFCs), phytoremediation/constructed wetland systems, in situ treatments systems employing bioagumentation, biostimulation have been developed recently for the treatment of textile dye wastewaters. Likewise, recent research has focused on guaging the microbial community structures and metagenomes of aerobic or anaerobic biotreatment systems to understand their roles and mechanisms in dye biodegradation in order to design efficacious bioremediation processes.
This Research Topic therefore, welcomes Original Research or Review articles focusing on all aspects of microbial biotechnology solutions for treatment of textile dye wastewaters. The topic encourages research contributions dealing with microbial systems for efficacious bioremediation of textile dye wastewater, understanding of microbial community structures and dynamics of treatment systems and “Omics” approaches such as metagenomics, metatranscriptomics, metabolomics to identify novel textile dye degradation genes, metabolites, pathways and microbial mechanisms during active bioremedation processes. Further, the Topic aims to explore integrated systems, hybrid bioreactors and combination of physico-chemical processes with microbial systems for enhanced removal of textile dyes from wastewaters. Contributions from experimental lab scale to field trials of microbial or integrated treatment systems and processes are of special interest. The primary objective is to compile recent developments in microbial technologies for treatment of textile dye wastewater, knowledge on microbial dye degradation mechanisms/metabolic pathways and role of microbial communities mediating bioremediation.
Following objectives will be covered by this Research Topic:
• Systematic investigations on bacterial, archaeal, fungal, algal strains, mixed cultures, consortia or communities for decolorization/degradation/mineralization of textile dyes in wastewaters.
• Studies elucidating mechanisms of textile dye biodegradation, characterization of microbial genes mediating textile dye bioremediation (for example, microbial azo reductases, laccases, lignin peroxidases).
• Eco-engineered microbial aerobic or anaerobic remediation technologies such as various types of bioreactors, sequential biological treatment systems, microbe-assisted phytoremediation, constructed wetlands, microbial fuel cells and bioelectrochemical treatment systems, plant-microbial fuel cells in bioremediation of textile wastewaters.
• Cross-disciplinary/hybrid approaches coupling bioremediation with physico-chemical processes such as advance oxidation processes (AOPs).
• Eco-sustainable Ex-situ and In-situ microbial/integrated bioremediation approaches focusing on pilot-scale or full-scale systems for treatment of textile dye wastewaters.
• Metagenomics, metatranscriptomics and metabolomics studies elucidating the microbial community stuctures and their synergistic functional roles in biodecolorization/degradation of textile dye wastewaters.
• Environmental auditing/cost analysis of microbial treatment systems, knowledge gaps, future perspectives/ pragmatic solutions for microbial textile dye bioremediation.
Please Note: All articles need to explore a clear hypothesis, merely descriptive articles and articles dealing with genome announcements won’t be considered for peer-review.
Keywords: Textile dye wastewaters, biodegradation, bioreactors, microbial communities, microbial fuel cells
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.