Dye Decolourization Research Articles

Lab scale evaluation of biomineralization-assisted decolourization of reactive blue 4 and toxicity analysis

The process of microbial mineral precipitation has proven to be highly effective in addressing a wide range of pollutants in different environments. The objective of this study is to utilize the mineralization abilities of microbial strains found in the Noyyal River basin, which is home to a significant textile center in India, in order to both remove the color from reactive blue 4 and promote biomineralization. Promising results were obtained from the microbial isolates Streptomyces sp., Rhodococcus ruber, and Bacillus sp., and their consortium which demonstrated the ability to induce biomineralization and decolorize reactive blue 4. Characterization of the obtained biominerals through X-ray diffraction and FT-IR analysis showed the presence of well-crystallized polymorphs of calcium carbonate, along with other organic compounds. SEM-EDX analysis of biominerals formed during biomineralization-assisted decolourization of RB4 revealed distinct morphologies and elemental composition of the biominerals produced by microbial interactions with dye molecules. Further, to assess the safety and efficacy of these biominerals, zebrafish embryo toxicity tests were conducted by comparing biominerals produced during dye decolourization with the pure reactive blue 4 dye. Zebrafish embryos treated with biominerals exhibited normal developmental patterns, whereas those exposed to reactive blue 4 displayed mortality and abnormal hatching rates. The heart rates of the Zebrafish embryos were normal for controls and biomineral groups, but lower for RB4-exposed embryos. In conclusion, this study underscores the potential of biomineralization in remediating dye-contaminated wastewater, offering circular solutions for waste reduction and resource utilization.

Synthesis of omega-3 mediated copper (ω-3-Cu) and copper oxide (ω-3-CuO) nanocatalyst dual application of dye decolourization and aerobic oxidation of eco-friendly sustainable approach.

In this study, ω-3-Cu and ω-3-CuO nanocatalysts were investigated for industrial environmental issues. Nowadays, green methodology is very important for addressing industrial environmental issues. In this regard, the current study focuses on ω-3-Cu and ω-3-CuO used for aerobic oxidation and dye decolourization via an eco-friendly approach. The synthesised ω-3-Cu and ω-3-CuO nanocatalysts were characterised using FT-IR, UV, XRD, TEM, GC-MS, 1H and 13C NMR. The results showed that the prepared ω-3-Cu catalyst was almost spherical with forms and sizes typically less than 20nm and the ω-3-CuO nanocatalyst 10nm. The ω-3 Cu and ω-3-CuO nanocatalysts were investigated for the conversion of pentan-2-ol into pentan-2-one, which was observed by GC-MS analysis. The ω-3-CuO nanocatalyst decolourised the Brilliant Blue dye more quickly (100% in 30min) than ω-3-Cu (85% in 60min) and ω-3 (no colour in 60min), and Rhodamine B was not decolourised because our ω-3-Cu and ω-3-CuO nanocatalysts inactivated the rhodamine B dye. The aerobic oxidation process using the ω-3-CuO nanocatalyst as the end product of pentan-2-one resulted in a retention time of 30.33. To the best of our knowledge, ω-3-Cu and ω-3-CuO nanocatalysts have not been documented for their application in decolourisation and aerobic oxidation. By highlighting the potential use for the continued advancement and innovation of ω-3-CuO nanocatalysts in the long-term future, cost-effective and eco-friendly methods for producing reusable ω-3-CuO nanocatalysts have the potential to be applied in advanced technical fields, particularly in the areas of dye decolourisation and aerobic oxidation. Finally, we successfully accomplished these processes using the ω-3-CuO nanocatalyst. The ω-3-CuO nanocatalyst evaporated more quickly than the ω-3-Cu and ω-3-CuO nanocatalyst, without any additional energy. ω-3-CuO is the most effective nanocatalyst for dye decolourization and aerobic oxidation (Dual application). ω-3-CuO is used in textile and pharmaceutical industries.

Methyl red dye decolourization by the photosynthetic bacteria, Rhodopseudomonas palustris and Afifellamarina

Anoxygenic photosynthetic bacteria are common inhabitants of wastewater: we found that Rhodopseudomonas palustris and Afifella marina in eutrophic conditions only partially degraded the azo dye (50 mmol m−3), Methyl Red, but completely degraded it under specially defined conditions. The azo dye is potentially a source of both carbon and fixed nitrogen. Rhodopseudomonas palustris and Afifella marina can live heterotrophically, photoheterotrophically or photoautotrophically under anoxic conditions where they can fix N2 if no organic nitrogen or NH3 is available. If organic carbon sources are available or if NH3 is present, the cells again only partially catabolised Methyl Red. In the absence of no alternative organic carbon sources and no NH3, the cells almost completely spectroscopically decolourised Methyl Red in 4 days. In sewage ponds the ready availability of alternative organic carbon and NH3 would result in only partial removal of Methyl Red. Rhodopseudomonas cells responded to the availability of Methyl Red in N-free media, by increasing both Optimum irradiance and maximum ETR (Eopt 276.3 μmol quanta m−2 s−1; ETRmax 391.4 μmol e− g−1 BChl a s−1) compared to control cells incubated in PM media with no organic carbon source and no fixed N-source (Eopt 115.2 μmol quanta m−2 s−1; ETRmax = 153.0 μmol e− g−1 BChl a s−1. If no alternative C or N sources are available, Rhodopseudomonas embedded in alginate biobeads will completely and repeatedly break down Methyl Red. The marine Afifella readily broke down Methyl Red but again breakdown was only complete if alternative carbon and no fixed nitrogen sources were available. The toxicity of the breakdown products produced by photosynthetic bacteria from azo-dyes needs to be followed up. Photosynthetic bacterial-alginate biobeads have long lifetimes (Rhodopseudomonas ≈ 2 months, Afifella > 6 months) making them of great biotechnological potential.

Recent Developments and Challenges in the Application of Fungal Laccase for the Biodegradation of Textile Dye Pollutants

Abstract: According to the European Environment Agency, the textile industry is responsible for 20% of global water pollution due to dyeing and finishing products, thus facing severe environmental challenges. It is essential to design more biocompatible and sustainable treatment processes capable of removing dyes from industrial wastewater to fight this environmental hazard. Chemical industries must change traditional chemical-based concepts to more environmentally friendly and greener processes to remove pollutants, including dyes. Enzymatic bioremediation is a smart tool and a promising alternative for environmental pollutant degradation. The use of enzymes in dye decolourization makes the process a green and clean alternative to conventional chemical treatments. Moreover, enzymemediated biocatalysis decreases the formation of toxic by-products compared to chemical reactions. The most used enzyme for the decolourization of dyes is laccase. Laccase is a multicopper oxidase found in diverse organisms such as fungi. It promotes the oxidation of phenolic compounds and has a wide range of substrate specificity, making it a promising enzyme for removing different dyes used by the textile industry, including recalcitrant aromatic dyes. The present article gives a comprehensive revision of textile dye decolourization, its types, recent developments in laccase-mediated dye bioremediation technologies, the mechanism of biocatalysis, and their limitations and challenges. Emphasis on the chemical pathways of laccase reaction mechanisms for dye bioremediation processes is also provided. In addition, a brief overview of textile industries and the respective traditional treatment processes for textile wastewater is presented.

Insights into the azo dye decolourisation and denitrogenation in micro-electrolysis enhanced counter-diffusion biofilm system

In this study, electron transport pathways were activated and diversified by coupling counter-diffusion biofilms with micro-electrolysis for Alizarin yellow R (AYR) denitrogenation. Due to the binding of AYR to two residues of EC 4.1.3.36 with higher binding energy, the expression of EC 4.1.3.36 was down-regulated, causing the EC 3.1.2.28 and EC 2.5.1.74 for menaquinone synthesis (redox mediator) undetectable in Membrane aerated biofilm reactors (MABR). Spontaneous electron generation in the micro electrolysis-coupled MABR (ME-MABR) significantly activated two enzymes. Activated menaquinone up-regulated decolourisation related genes expression in ME-MABR, including azoR (2.12 log2), NQO1 (2.97 log2), wrbA (0.45 log2), and ndh (0.47 log2). The diversified electron flow pathways also promoted the nitrogen metabolism coding genes up-regulation, accelerating further inorganic nitrogen denitrogenation after AYR mineralisation. Compared to MABR, the decolourisation, mineralisation, and denitrogenation in ME-MABR increased by 25.80 %, 16.53 %, and 13.32 %, respectively. This study provides new insights into micro-electrolysis enhanced removal of AYR.

Deciphering the ecological impact of azo dye pollution through microbial community analysis in water-sediment microcosms.

The uncontrolled release of untreated dyeing wastewater into aquatic ecosystems poses global environmental risks. It alters native microbial communities and associated ecological processes, often going unnoticed. Therefore, the influence of acid orange 7dye (AO7) contamination on the natural microbial community was investigated using a water-sediment microcosm. Compared to sterile microcosms, complete dye decolourization in natural microcosms showed microbial communities' significance in combating xenobiotic contamination. Proteobacteria dominated the water community, whereas Firmicutes dominated the sediment. AO7 exposure induced notable shifts in the structural composition of the bacterial community in both water and sediment. Niveispirillum exhibited a marked decrease, and Pseudomonas demonstrated a notable increase. The - 9.0 log2FC in Niveispirillum, a nitrogen-fixing bacterium, from 24.4% in the control to 0.1% post-treatment, may disrupt nutrient balance, plant growth, and ecosystem productivity. Conversely, elevated levels of Pseudomonas sp. resulting from azo dye exposure demonstrate its ability to tolerate and bioremediate organic pollutants, highlighting its resilience. Functional profiling via KEGG pathway analysis revealed differential expression patterns under AO7 stress. Specifically, valine, leucine, and isoleucine degradation pathways in water decreased by 52.2%, and cysteine and methionine metabolism ceased expression entirely, indicating reduced protein metabolism and nutrient bioavailability under dye exposure. Furthermore, in sediment, glutathione metabolism ceased, indicating increased oxidative stress following AO7 infusion. However, C5-branched dibasic acid metabolism and limonene and pinene degradation were uniquely expressed in sediment. Decreased methane metabolism exacerbates the effects of global warming on aquatic ecosystems. Further, ceased-butanoate metabolic pathways reflect the textile dye wastewater-induced adverse impact on ecological processes, such as organic matter decomposition, energy flow, nutrient cycling, and community dynamics that help maintain self-purification and ecological balance in river ecosystems. These findings underscore the critical need for more comprehensive environmental monitoring and management strategies to mitigate ecological risks posed by textile dyes in aquatic ecosystems, which remain unnoticed.

ENHANCEMENT OF PHENOLIC CONTENT AND ANTIOXIDANT PROPERTIES THROUGH CHEMICAL AND BIOCHEMICAL REATMENT OF LIGNIN-RICH RICE STRAW RESIDUE

Valorization of lignin in biorefineries is important as this can lead to enhancement of chemical and physical properties of lignin, making it suitable for applications in polymers, composites and adhesives. Lignin valorization requires overcoming recalcitrance and tailoring for different uses. Here, lignin was extracted from rice straw lignin-rich residue at pH 12, using 4% magnesium oxide and 6% sodium hydroxide on a dry w/w basis. The extracted lignin-rich stream, which had a pH in the range of 9-10, was used further for biochemical transformation. Towards that end, Pseudomonas putida, Sphingomonas paucimobilis, Pseudomonas fluorescens and Bacillus tequilensis were screened for their capability of aromatic dye decolourization. The results of the study show an increase in the total phenolic content in lignin between 50% and 55% after 144 h of treatment with Pseudomonas putida. Concomitant with the increase of phenolics, a four-fold increase in antioxidant activity in gallic acid equivalents was also observed when Pseudomonas putida was used.

Decolourization and detoxification of Reactive Red-195 azo dye by Staphylococcus caprae isolated from textile effluent.

Azo dyes are used as coloring agent in textile industries at larger scale. As a result, large quantity of dye-enriched waste water is generated which subsequently poses environmental problems. Biological tool involving bacteria having azoreductase enzyme has proved to be more effective and efficient in dye effluent treatment. Current work focuses on Staphylococcus caprae (S. caprae) for degradation and decolorization of Reactive Red-195 (RR-195) azo dye. For this purpose, factors such as pH, temperature, inoculums, carbon and nitrogen sources, and dye concentrations have been optimized for maximum decolorization and degradation. S. caprae (4mg/mL) efficiently resulted into 90% decolorization of RR-195 dye under static condition at 100µg/mL concentration, 30°C and pH 7.0 at a 12-h contact period. FTIR analysis has revealed the formation of new functional groups in the treated dye such as O-H stretch at 3370cm-1, C-H band stretching at 2928cm-1, and new band at 1608cm-1 which specify the degradation of aromatic ring, 1382 and 1118cm-1 represents desulfonated peaks. Biodegraded metabolites of RR-195 dye such as phenol, 3, 5-di-tert-butylphenol, and phthalic acid have been identified respectively that find industrial applications. Phytotoxicity test has shown non-toxic effects of treated dye on germination of Vigna radiata and Triticum aestivum seeds. Further, antibiotic diffusion assay has confirmed the biosafety of S. caprae.

Catalytic degradation of water micropollutants and LED-assisted decolourisation of Sudan dyes via mycosynthesised gold nanoparticles

Catalytic degradation of water micropollutants and LED-assisted decolourisation of Sudan dyes via mycosynthesised gold nanoparticles

Immobilization of HRP enzyme on polymeric microspheres and its use in decolourisation of organic dyes

In this study, horseradish peroxidase (HRP) enzyme was immobilized on Pd(II) containing polymeric microspheres by adsorption method and used for the decolourisation of Methyl Orange (MO) and Rhodamine B (RB) dyes. The synthesized microspheres were characterized by Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy-Energy Dispersive X-ray (SEM/EDX), Thermal Gravimetric Analysis (TGA). The effects of pH, dye concentration, temperature, and H2O2 concentration on the decolourisation of MO and RB were determined. According to the results of various parameters studied, when 2-AEPS-napht-HRP support was used, MO and RB were biodegraded to 69.72% and 80.65%, respectively, within 60 min. When 2-AEPS-napht-Pd-HRP support was used, MO and RB were biodegraded to 58.35% and 90.81%, respectively, under optimum conditions. When the reproducibility results of the immobilized supports were examined, it was observed that they remained efficient during the first five reusability cycles and even reached 65% decolourisation efficiency after the 9th reuse. The immobilized enzyme (2AEPS-npht-HRP and 2AEPS-npht-Pd-HRP) showed remarkable resistance to higher temperatures compared to the free enzyme.

Assessment of Biodegradation and Phytotoxicity of Azo Dyes Methyl Orange and Crystal Violet by Escherichia coli and Bacillus subtilis

Azo dyes are widely used colourants, possess array of colours and are generally recalcitrant to microbial degradation. This study aimed to isolate azo dyes degrading bacteria from soil; treat methyl red and crystal violet dyes using the isolates, and assess the phytotoxicity of the treated and untreated dyes on sorghum. Ten bacteria were isolated from the soil, of which two were identified as efficient azo dyes degrading bacteria by efficiency in dye decolouration. The isolates were identified as Escherichia coli and Bacillus subtilis based on their biochemical characteristics. The isolates were able to degrade methyl orange dye by 16-75 % and crystal violet by 16-78%, depending on the concentration of the dye. The isolates were more efficient at degrading the dyes at a low concentration of 0.00025 mg/ml, as indicated by a higher percentage of decolourization (53-79%). The percentage phytotoxicity of the untreated methyl red ranged from 33-59%, while the toxicity of the untreated crystal violet ranged from 62-91%. The toxicity of the treated methyl red ranged from 9-34%, while the toxicity of the treated crystal violet ranged from 12-32%. The results revealed that the isolates were capable of degrading methyl red and crystal violet dyes, and could be useful in the bioremediation of azo dyes polluted soil.

Photocatalytic degradation of Direct Black 10 B dye in aqueous phase using nanophotocatalyst

ABSTRACT In this study, the photocatalytic degradation of an aqueous solution containing a mixture of Direct Black 10 B dye using titanium dioxide (TiO2) as a catalyst was investigated. The degradation of Direct Black 10 B dye was studied for several parameters, including the catalyst, dosage, initial concentration of dye, and pH. Variable catalyst quantities (0.25, 0.50, 0.75, 1, and 1.25 g), pH (3, 5, 9, and 11), and beginning dye concentration were used in the studies (62.5, 125, 250 and 500 ppm). 0.75 g/litre of catalyst was found to be the ideal dose. The ideal catalyst concentration was determined to be 0.75 g/litre, and the maximal dye decolourization rate was further studied in a basic media, i.e. at pH 9 Blue turned into grey and finally white in the acidic medium, whereas blue turned into pink and then white in the basic medium. After 3 hours 98% of the colour was completely removed at this optimal point. The Langmuir, Freundlich and Temkin isotherms were examined. The langmuier isothers with regression coefficient 0.99 is best fitted as compared to Freundlich and Temkin isotherms. The findings of the kinetic analysis suggest that the Pseudo Second order with regression coefficient 0.9923 is best suited as compared with the pseudo first order and Intra-particle diffusion model.

Musa acuminata free tepal (MAFT) crop- mediated synthesis of copper oxide nanocatalyst (MAFT-CuO nanocatalyst): Investigation of aerobic oxidation and dye decolourization via eco-friendly approach

Crop development is used to address environmental problems in the industry. Environmental pollutants, particularly humble or toxic chemicals and dyes, are contaminants in industrial wastewater. Recently, green technology has become important for controlling the chemical risks associated with environmental issues. This study focused on valuable crop materials to form green catalysts that can be used to control chemical toxicity in industrial wastewater. In this study, Musa acuminata-free tepal (MAFT) crops and musa were used to mediate the formation of copper nanocatalyst for environmental pollution. The synthesised nanocatalyst was analysed by XPS, XRD, TEM, SEM, FT-IR, GC-EI-MS, and TGA-DSC. The production of Cu–O in the 512 cm−1 peak range was verified by FT-IR analysis. The XRD peaks associated with the cubic crystalline structures of copper (110) and (200) were used to confirm the Musa acuminata-free tepal CuO nanocatalyst. The SEM images of the Cu and CuO nanocatalyst in the Musa acuminata free tepal showed that the particles were almost spherical. The size of the synthesised Musa acuminata free tepal CuO nanocatalyst core-shell nanostructures was identified using HR-TEM. GC-MS investigations also verified the aerobic oxidation of the main alcohol to aldehyde, with a retention time of 30.34. The MAFT was 80 % of CBB G250 dye decolourised at 24 h, and the MAFT-CuO nanocatalyst was decolourised the CBB G250 dye at 80 % in 20 min and aerobic oxidation at the same time (dual application). Furthermore, our nanocatalyst could be effectively recycled without significant loss of catalytic activity, and the use of safe, environmentally benign MAFT-Cu and CuO nanocatalyst is considered a green chemistry approach that helps avoid wastewater treatment. MAFT-Cu and CuO nanocatalyst were successfully synthesised using Musa acuminata free tepal extract assisted by reflux sample preparation system instruments as a new, green, eco-friendly, and fast process for nanocatalyst synthesis. In the past, there have been no reported applications of MAFT-Cu and CuO nanocatalyst for decolourisation and aerobic oxidation. Nevertheless, we were able to accomplish these procedures with the help of CuO and MAFT-Cu nanocatalyst. Therefore, the most effective naturally occurring environmental catalysts for aerobic oxidation processes are MAFT-CuO nanocatalyst. They are non-toxic and environmentally benign, exhibit strong aerobic oxidation catalytic performance, and have long-lasting benefits for water quality. Additionally, they are more recoverable and biodegradable.

Bioprospective decolourization of reactive azo dyes at pilot scale by a developed bacterial consortium using the RSM and CCD model

Bioprospective decolourization of reactive azo dyes at pilot scale by a developed bacterial consortium using the RSM and CCD model

Brilliant green decolorization by dye decolorizing peroxidase producing bacterium, Achromobacter insolitus isolated from Forest soils of Similipal Biosphere Reserve, Odisha

Dye-decolorizing peroxidases (DyPs) are recently identified superfamily of heme-containing peroxidases which has received much attention for its potential application in dye decolourization. In the current research, six bacterial colonies (SDB1-6) showing lignolytic activity were isolated from forest soils of SBR using a minimal salt medium supplemented with alkali lignin and screened for DyP activity using brilliant green dye supplemented luria bertani agar medium. The highest DyP activity showing bacterium was identified using biochemical and 16SrRNA sequencing and was identified as Achromobacter insolitus. A. insolitus was found to be an efficient strain showing the highest DyP activity of 2.7 U/mL/ml at un-optimized condition. The RSM optimization was conducted to increase the DyP enzyme activity. A. insolitus demonstrated DyP activity of 6.20 U/mL/min with an increase of 2.29 times of enzyme activity in optimal condition of pH 7.0, temperature 25 °C, H2O2 concentration 0.1 mM, and time 24 h. The bacterium was further screened for dye decolorization taking crystal violet, methyl orange, methylene blue, brilliant green and methyl red dyes supplemented in LB medium. The bacterium showed maximum brilliant green degradation ability was analyzed using UV-Vis and FTIR analyses to characterize the degraded product. The highest brilliant green degradation activity of the A. insolitus in the present study could be exploited for bioremediation of brilliant green contaminated industrial effluents in a ecofriendly and cost effective way.

Biofabrication, spectroscopic, and photocatalytic studies of titania nanoparticles mediated by Proteus mirabilis strain NG-ABK-32 for smart applications

ABSTRACT Green fabrication of nanoparticles (NPs) is simple, pocket-friendly, easy, sustainable, and devoid of eco-toxicity issues. Thirty-five bacterial strains were isolated from ‘tie and dye’ effluent-contaminated soil and effluent samples and were identified using traditional methods. Following a dye decolourization assay, Proteus mirabilis strain (NG-ABK-32) emerged as the isolate with the highest potential to decolourize vat violet RR dye. Titania nanoparticles (TiO2 NPs) fabricated using NG-ABK-32 strain were characterized by UV-visible spectroscopy (UV-vis), Transmission Electron Microscopy (TEM), X-ray Diffraction (XRD), and Fourier Transform Infrared (FT-IR) spectroscopy. UV-Vis result displayed an absorption peak at 320 nm. The TEM image revealed monodispersed, spherical NPs possessing an average particle size of 3.18 nm. The crystallographic plane of rutile TiO2 NPs and high purity were confirmed by the XRD pattern. The average crystallite size was 52.53 nm. The synthesis of TiO2 NPs was further established from FT-IR by the presence of Ti-O, Ti-OH, and O-Ti-O functional groups. The synergistic treatment caused a significant reduction of total suspended solids (TSS), total dissolved solids (TDS), biological oxygen demand (BOD), chemical oxygen demand (COD), and color (Pt.Co) of the effluent by 96.86%, 78.78%, 67.84%, 56.65%, 67.84%, and 72.09% respectively. Thus, this study confirmed the better efficiency of combining biological (NG-ABK-32) pre-treatment with photocatalytic degradation post-treatment using the synthesized TiO2 NPs in the treatment of ‘tie and dye’ effluent compared to the application of the TiO2 NPs as a single treatment method.

Valorization of sugarcane bagasse for high-yield production of laccase through Aspergillus terreus for effective azo dye decolourization

Synthetic dyes such as azo dyes are significant pollutants in the wastewater released from various textile industries. The low biodegradability and production from synthetic sources with high shelf life make azo dyes a challenging material for degradation. This study used chemically mutated Aspergillus terrus in the laccase production under solid-state fermentation using sugarcane bagasse. Initially, the wild-type strain produced a laccase activity of 4.12 U/mL. Later, the alkaline pretreatment of sugarcane bagasse showed a significant increase in laccase activity by 38.9%. Further, random mutagenesis treatment with 100 mM EMS generated a hyper laccase-producing strain with a 2.3-fold increment in laccase activity compared to the wild-type strain. The enzyme displayed optimal activity at pH 6.5 and 35 °C. The metal ions such as Fe3+ (29.4 U/mL), Fe2+ (20.8 U/mL) and Cu2+ (18.05 U/mL) showed positive effects on laccase activity. The crude laccase was used to bioremediate Congo red, a prominent azo dye used in textile and pharmaceutical industries. The preliminary studies with a crude enzyme displayed 68.86% dye decolourization after 24 h of incubation. Additionally, with Taguchi orthogonal array optimization experiments, the maximal dye decolorization of 78.24% was achieved by maintaining crude enzyme concentration (20 U), dye concentration (25 mg/L) and pH 4.5.

Effect of co-cultivation of white and brown rot species on basidiome production, lignocelluloytic enzyme activity and dye decolourisation

The aim of this work was studying the impact of co-cultivating two mushroom species: a white (Pleurotus albidus CLA 45) and a brown rot one (Laetiporus sulphureus BAFC 205) in substrates based on poplar or pine sawdust, on their lignocellulolytic enzyme production, yield values and basidiomes properties. Laetiporus sulphureus only developed basidiome primordia, but P. albidus monoculture and co-culture in pine sawdust achieved biological efficiencies of up to 50–55 %. Co-cultivation on diverse substrates rendered varied enzyme titers. Laccase and Manganese peroxidase titers were highest in pine co-culture and P. albidus poplar monoculture, respectively. Enzymatic extracts obtained from spent poplar substrate of dual cultures displayed potential for treating non-sterile textile-coloured effluents, achieving 35 % decolourisation after 120 h. The knowledge available on the effects of co-culture of white and brown rot fungi is still limited. This study represents an initial exploration of the interaction between them within intensive cultivation conditions.

Sustainable approach for the degradation of Contrast dye Evans blue by Enterobacter cloacae strain SD4-1

BackgroundDischarge of dye complexes through industrial effluents continues to be a never-ending problem for the environment. Several degradation techniques have been experimented with, of which utilizing biological entities for the effective degradation of these dye molecules is extensively studied and still being explored. The present study focuses on (i) isolation of bacterial strains from the contaminated agricultural lands (ii) screening the isolates for their decolourization efficiency of Evans blue dye (iii) optimization of culture parameters such as temperature, pH, concentration of dye and nitrogen source for effective decolourization (iv) analysing the effect of degradation of diazo dye Evan's blue by the selected strain using GCMS analysis. MethodsThe bacterial strains were isolated from contaminated agricultural lands in Chennai, Tamil Nadu, India. The collected samples were aseptically transferred to the laboratory and stored for further studies. The collected samples were serially diluted, and the colonies with distinct morphology were pure-cultured. The isolated strains were studied for their efficiency to decolourize the dye Evans blue dye. The strain with higher decolourization efficiency was selected and optimized for parameters such as temperature, pH, nitrogen source and concentration of dye. The degradation of dye by the isolate was analysed by GCMS. Significant FindingsThe investigation unveiled that the strain SD4-1 of Enterobacter cloacae effectively decolorizes Evans blue dye at 37°C and pH 6.0, utilizing Sodium nitrate as the nitrogen source. SD4-1 exhibited an impressive dye decolourization efficiency of approximately 75%. The comprehensive GCMS analysis verified the bacterium's capability to fully degrade the azo dye Evans blue. Consequently, this study concludes that the SD4-1 Enterobacter cloacae strain holds promising potential for the efficient biodegradation of Evan's blue dye. Its application as a highly effective biological agent in the practical removal of dyes from textile industries is envisaged. Notably, this organism demonstrates superior performance in comparison to other studies where a mixture of dyes or consortia of microorganisms were employed for dye decolourization.

Design and development of symmetric aromatic bischalcogenide-based photocatalysts for water treatment application: a concise study of diphenyl diselenide polypyrrole nanocatalysis.

Dopant engineering can be a very selective approach in designing hybrid materials. Incorporating the required functionality in a dopant effectively modulates its properties towards aimed applications. Consequently, this work through a comparative study envisaged the incorporation of chalcogenides (S, Se, and Te) in a biphenyl motif based on the analysis of major photocatalytic descriptors. Bischalcogenides as tuned dopants have been impressive in enhancing the surface area, increasing crystallinity and facilitating band gap shifts towards better light harvesting. In addition, the chalcogen effect was observed to induce preferential ion migration, leading to effective charge separation and attenuated recombination rates. Photocatalytic descriptors evaluated from electrochemical impedance spectroscopy and photoluminescence data corroborated the chalcogen effect in the observed trend (Ph)2 < (PhS)2 < (PhSe)2 < (PhTe)2. The diphenyl diselenide polypyrrole nanocomposite emerged to be better among the studied systems. (PhSe)2/PPY was characterized and comprehensively evaluated for its photocatalytic activity towards varied dye classes and the colorless isoniazid antibiotic under environmentally viable conditions. Its calculated band potential values and scavenger experiments indicate OH˙ and O2 ˙- as dominant species in its photocatalytic activity. Control experiments confirmed photocatalytic degradation over photolysis as the dye decolouration mechanism. Taken together, (PhSe)2/PPY emerges as a good propensity photocatalyst worthy of real time customization for wastewater treatment on a pilot scale.