Remazol Brilliant Blue R Research Articles

Interfacial interactions in aqueous systems of poly(ε-caprolactone)-co-poly(2-hydroxyethyl methacrylate) hydrogel with dye molecules in synthetic wastewaters

The use of dyes is widespread in the textile business, having various detrimental effects on humans and ecosystems. When dying, both cationic and anionic dyes are used. A lot of studies have been conducted in order to find an effective eco-friendly solution to resolve this issue. In this study, we recommend the use of an amphoteric and amphiphilic hydrogel consisting of ε-caprolactone and 2-hydroxyethyl methacrylate which are both biodegradable and cost-effective. The synthesis of this material was confirmed by FTIR, XRD, and SEM. The parameters under which the composite was adsorptively examined were the effects of pH, temperature, and contact time. It was found that the kinetics followed the pseudo fractal-like first order kinetic model for Μethylene Blue, while for Remazol Brilliant Blue R, both the pseudo fractal-like first order and the pseudo-second order models describe the data equally well. Thermodynamic analysis indicated that the adsorption process of both dyes was endothermic and spontaneous. Reuse experiments showed that their removal efficiency was retained at high levels, while stability studies revealed that the hydrogel retains its structural integrity, even at extreme pH values. Finally, the poly(ε-caprolactone)-co-poly(2-hydroxyethyl methacrylate) approach appears to be a viable strategy for removing dye residues from wastewater that is both successful and ecologically acceptable.

Identification and Evaluation of Locally Isolated Fungi Through Rapid Screening for Potential Mycelium-Based Biofoam Application in Malaysia

Expanded polystyrene foam (EPS) contributes to environmental problems due to its inability to decompose in nature within a short period. In addition, petroleum as a core source for EPS is now depleting and new biological and environmentally friendly approaches are encouraged. As an alternative to EPS, mycelium-based biofoam (MBF) is a new foam technology formed of agricultural biomass and mycelium as a binding matrix is introduced. However, based on previous literature, the fungal strains used are mainly highlighted as one of the main factors which affect the final properties of MBF. Thus, this study aims to evaluate the most potential fungus used for MBF application using OPEFB, biomass from the palm oil industry as novel substrate using rapid screening. Twelve local fungi isolated from a local forest in Selangor, Malaysia were cultivated on Potato Dextrose Agar and OPEFB plate before being screened on agar containing four different types of dye indicators, which are methylene blue, guaiacol, Remazol Brilliant Blue R and azure B. As a result, Phanerochaete concrescens isolate LYN-UPM S1 and Perenniporia subtephropora isolate LYN-UPM S9 have shown the ability to produce ligninolytic enzymes and high content of chitin, which will be useful for the fabrication of mycelium-based biofoam.

Heterogeneous Fenton process using GO@Fe3O4/Cu catalyst for the degradation of reactive dyes from aqueous solutions: modeling and optimisation

ABSTRACT Various industries such as textile, paper, rubber, plastic, and cosmetics use dyes to produce their products. Some dyes used in textile industries are teratogenic, carcinogenic, mutagenic, and dangerous for humans and other organisms. This study aimed to determine the amount of removal of reactive dyes from aqueous solutions during the heterogeneous Fenton process. In this study, iron oxide nanoparticles and copper nanoparticles were loaded on graphene oxide (GO). GO@Fe3O4/Cu catalyst was synthesised and applied to remove reactive dyes from aqueous solutions in a heterogeneous Fenton process. Contact time, pH, catalyst dose, dye concentration, and H2O2 dose were considered effective parameters. Experiments were designed according to the Box-Behnken design in the Design Expert software. Catalyst properties were determined using SEM, VSM, XRD, and FTIR analysis. The ANOVA showed that the selected statistical model with R2 0.965, p < 0.0001, and F-value 27.79 was significant. In the optimal conditions of pH 3, H2O2 dose 0.48 mL, catalyst dose 0.34 g/L, dye concentration 22 mg/L, and contact time 9 min, the degradation efficiency of Reactive Blue 21 (RB21), Reactive Red 195 (RR195) and Reactive Red 19 (RR19) were 92, 97, and 80%, respectively. The results showed that after 5 cycles of recycling, the catalyst had a high efficiency in pollutant removal and could be utilised many times for dye decomposition. GO@Fe3O4/Cu catalyst was successfully synthesised using a simple method. The heterogeneous Fenton process with a magnetic catalyst in the presence of H2O2 has a high potential to remove reactive dyes from the aqueous solution.

Short Communication: Candida sp. isolated from mangrove soils for biological decolorization of textile reactive dyes

Abstract. Boontanom P, Chantarasiri A. 2024. Short communication: Candida sp. isolated from mangrove soils for biological decolorization of textile reactive dyes. Biodiversitas 25: 2595-2602. Effluent discharge from dye-related industries is a significant environmental pollution problem and a concern for human health. Dyes have harmful effects on aquatic organisms due to their toxic properties. One possible solution is using microorganisms for the biological decolorization of textile reactive dyes as an eco-friendly and potentially lucrative alternative to physicochemical processes. Therefore, this study isolated an effective dye-decolorizing yeast from mangrove soil samples in Thailand and investigated the decolorization efficiency of eight textile reactive dyes under experimental conditions. Yeasts have several advantages over other bacteria and fungi for the biological decolorization of textile reactive dyes, but the number of dye-decolorizing yeasts discovered in mangrove soils remains scarce. The most effective dye-decolorizing yeast, isolate RY21703, showed Remazol Brilliant Blue R (RBBR) decolorization of 37.50±0.07% within 72 h of incubation. This yeast isolate was genetically and phylogenetically identified as Candida sp. strain RY21703 and produced 0.97±0.08 U/mL of crude laccase activity, an essential enzyme in dye decolorization mechanisms. Candida sp. strain RY21703 showed strong decolorization efficiency after 72 h of incubation in all azo-reactive dyes, ranging from 27.32±3.34% (CI Reactive Orange 122) to 61.45±1.43% (CI Reactive Green 19). This strain also decolorized phthalocyanine reactive dye (CI Reactive Blue 21) by 60.71%. Findings suggested that this mangrove yeast can be used for the biological decolorization of dyeing wastewater.

Degradation of Anthraquinone dye wastewater by sodium percarbonate with CoO heterogeneous activation

AbstractBACKGROUNDAnthraquinone dyes have an anthraquinone structure as their nucleus, with one or more substituents forming different organic dyes. Anthraquinone dyes have a complex structure that allows them to exist stably in water environment, but also makes them more toxic than azo dyes. This results in varying degrees of harm to both humans and the environment as a result of residual dyes in the water or on the material’ surface. Sodium percarbonate (SPC) is a highly promising oxidant due to its green end product. Therefore, in this study, the catalytic performance and kinetic study of cobalt oxide (CoO) on SPC under different conditions were systematically investigated using RB19 as the target pollutant. The Box–Behnken Design (BBD) model was used to model the degradation of RB19 by CoO/SPC system, which gives the basis for practical application. The types of reactive oxygen species that effectively degrade RB19 and the potential degradation mechanism of the CoO/SPC system were revealed. At the same time, the CoO/SPC system was evaluated in terms of its practicality.RESULTSIn this work, the activation of SPC using CoO towards reactive blue 19 (RB19) degradation was explored. Experimental results showed that nearly 93.8% of RB19 could be removed within 30 min using 1 mmol L−1 SPC and 30 mg L−1 CoO. The three‐factor interaction effects of SPC concentration, CoO dosage and initial pH were investigated. The BBD model was set up to obtain the optimum working conditions of 1.039 mmol L−1 SPC, 33.35 mg L−1 CoO and the initial pH of 7.82, which gave a degradation rate of 95.372%. Additionally, it was confirmed that the solubility of Co2+ is consistently &lt;150 μg L−1, meeting the emission standard (1 ppm). The presence of Cl−, NO3–, and HA had a similar profile, with a slight promoting effect in small amounts and an inhibitory effect when introduced in excess. The introduction of SO42– had a negligible effect on RB19 degradation, whereas the presence of HCO3− produced a slight inhibitory effect. Furthermore, the presence of PO43– showed a strong inhibitory effect. The CoO/SPC system is suitable for other organic dyes (32.7%–100%) and antibiotics (97.1–100%). Electron paramagnetic resonance (EPR) analysis and quenching experiments confirmed the presence and relative contribution of free radicals in the CoO/SPC system as CO3•‐ (88.12%) &gt;O2•‐ (51.11%) &gt;1O2 (37.21%) &gt;•OH (5.27%) &gt; SPC (3.33%) &gt;CoO (0.09%). It has been confirmed that CoO activates SPC through electron transfer.CONCLUSIONThe present study describes a less time‐consuming, and more efficient method of treating anthraquinone dye wastewater that requires less oxidizer and catalyst, making it more economical. This proposes a straightforward, cost‐effective and efficient technique using SPC triggered by transition metal oxides. © 2024 Society of Chemical Industry (SCI).

Improved expression of Cerrena unicolor Laccase in Aspergillus niger via combined strategies and its applications

The application of laccases in biotechnology and industry is an expanding research field. Laccases derived from Cerrena unicolor (C. unicolor) exhibit notable potential in the food and industrial sectors. However, generating sufficient yields of this laccase through heterologous expression to meet commercial demands remains a challenge. Therefore, we heterologously expressed LACCASE2 (Lac2), a laccase gene from C. unicolor, in Aspergillus niger. By incorporating strategies such as codon optimization, molecular chaperone-assisted expression, and atmospheric and room-temperature plasma (ARTP) mutagenesis, we successfully screened the strain OPT-HacA-M10 with the highest laccase yield, which exhibited a remarkable enzymatic activity of 416.8 U/mL in a 50-L fermenter. We further assessed the enzymatic properties of the recombinant laccase rLac2, focusing on its capabilities in dye decolorization and mycotoxin degradation. In the absence of a mediator, rLac2 exhibited extremely high degradation efficiency for Remazol Brilliant Blue R and indigo. Impressively, outstanding results were achieved with this laccase in denim bleaching. In mycotoxin degradation tests, with methyl syringate as a mediator, rLac2 achieved degradation rates of over 94% for aflatoxin B1 and zearalenone. In summary, due to its heightened laccase activity and versatile applications, our enhanced strain is highly suitable for industrial and food sectors.

Graphene oxide dots‐loaded chitin flask: A sustainable adsorbent for separating multiple dyes from water

AbstractThis research endeavors to comprehensively explore the sorption dynamics of dyes from aqueous solutions utilizing a graphene oxide‐chitin (GO‐chitin) biosorbent. The investigation systematically evaluates the influence of key parameters, including temperature, pH, duration of contact, and initial dye doses, on the sorption efficiency of the biosorbent. Results obtained indicated that at acidic pH range, the dye removal efficacy was more than 80% for methyl orange and Remazol Brilliant Blue. Maximum removal efficacy was achieved within the 30 min of adsorption studies. Notably, the study underscores the remarkable adsorption capacity of GO‐chitin, varies in the range of 75% and 95%, for all three dyes, positioning it as a highly promising material for the remediation of polluted aquatic environments. The adsorption follows pseudo‐second‐order kinetics and Freundlich isotherm. These findings contribute valuable insights into the potential application of GO‐chitin as an effective biosorbent in the context of wastewater treatment, emphasizing its role in addressing environmental challenges associated with dye contamination in aqueous systems.

Zygnema sp. as creator of copper oxide nanoparticles and their application in controlling of microbial growth and photo-catalytic degradation of dyes

Recently, focus has been placed on renewable sources, as they can be provided in large quantities at the lowest possible cost, in order to create nanoparticles. One of these sources is Zygnema moss which used in the present investigation to create Copper oxide nanoparticles (CuONPs). Several phenols and flavonoids were identified the extract of Zygnema sp. via analysis of High performance liquid chromatography. These constituents served as reducing and stabilizing agents for CuONPs. Characterization of CuONPs was performed via UV-visible spectrum that demonstrated peak at 252 nm, Transmission electron microscopy that showed spherical CuONPs with mean diameter of 30.06 nm, Fourier transform infrared spectroscopy that confirm that presence of several functional groups aided to formation of CuONPs. The crystallographic pattern of CuONPs was recorded via X-ray diffraction analysis. Antimicrobial potential of CuONPs was compared to copper acetate and antibiotic/antifungal drug. CuONPs exhibited more inhibition zones against S. aureus (32 ± 0.1 mm), E. coli (36 ± 0.1 mm), S. typhi (27 ± 0.2 mm), E. faecalis (37 ± 0.1 mm), C. albicans (34 ± 0.3 mm) than copper acetate and antibiotic/antifungal drug. Promising MIC values of were recorded against S. aureus, E. coli, and S. typhi. CuONPs at 200 ppm inhibited the growth of C. lunata, F. oxysporium, A. flavus, and Mucor circinelloid with inhibtion of 76.92, 73.33, 63.63, and 53.84%, respectively regarded the control 100% growth. The photocatalytic role of CuONPs was recorded for degradation of reactive red (RR195) and reactive blue (RB) dyes with maximum degradation of 84.66% and 90.82%, respectively at 75 min. Moreover, the optimal dyes degradation was 84.66 and 90.82%, respectively at 40 °C.

Exploring fungal-mediated solutions and its molecular mechanistic insights for textile dye decolorization

Decolorization of textile dyes and study of their intermediate compounds is necessary to comprehend the mechanism of dye degradation. In the present study, different fungal mediated solutions were explored to provide an alternative to treat the reactive dyes. Growing biomass of Pleurotus sajor caju showed 83% decolorization (249.99 mg L−1 removal) of Reactive Blue 13 (RB 13) and 63% decolorization (188.83 mg L−1) of Reactive Black 5 (RB 5) at 300 mg L−1 initial concentration on 8 d. Higher laccase activity was positively correlated with increase in decolorization. However, increasing dye concentration has inhibitory effect on fungal biomass due to increase in toxicity. In laccase mediated decolorization, laccase produced from P. sajor caju using carbon rich waste material as substrate showed 89% decolorization (276.36 mg L−1 removal) of RB 13 and 33% decolorization (105.37 mg L−1 removal) of RB 5 at 300 mg L−1 initial dye concentration in 100 min at 30 °C and pH 3.0’. Comparing the two methods, laccase-mediated decolorization shows better decolorization in less time and does not produce sludge. Further, the present work also attempted to study the dye degradation pathway for Reactive blue 13 via laccase mediated process. Fourier-transform infrared spectroscopy (FTIR), high-performance liquid chromatography (HPLC), and gas chromatography–mass spectrometry (GC-MS) were utilized to identify the degraded products. The GC-MS analysis showed the formation of naphthalene, naphthalene 2-ol, benzene,1–2, dicarboxylic acid, 4, amino, 6,chloro, 1-3-5, triazin-2-ol as the final degraded products after enzymatic degradation of RB 13. These findings provide in-depth study of laccase-mediated textile dye degradation mechanism.

0D/1D CuO-Cu2O/ZnO p-n heterojunction with high photocatalytic activity for the degradation of dyes and Naproxen

The development of highly active photocatalysts with broad spectrum response is of paramount importance for photocatalytic applications. Herein, heterostructured CuO-Cu2O/ZnO photocatalysts were prepared in a single step and under mild conditions using a photodeposition process which allows to deposit CuO-Cu2O particles with an average size of ca. 2.4 nm on the surface of ZnO nanorods. The p-n heterojunction built between CuO-Cu2O and ZnO allows to increase both the visible light response of the photocatalyst and the charge separation. The CuO-Cu2O(10%)/ZnO catalyst exhibits the highest activity for the degradation of dyes (Rhodamine B and Remazol Brilliant Blue R) and of Naproxen under simulated solar light irradiation. Based on scavenging experiments, holes, superoxide radicals O2●- and singlet oxygen 1O2 are the dominant species involved in the photocatalytic degradation and a mechanism is proposed. Due to its high stability and photocatalytic performance in various water matrices, the CuO-Cu2O(10%)/ZnO nanohybrid is of high potential for the large scale remediation of organic pollutants in wastewater.

Kinetics study of photocatalytic oxygen indicator reactions

The indicators are comprised of TiO2, Remazol Brilliant Blue R, glycerol, and polymer. Two different polymer matrices, poly(vinyl acetate) (PVAC) or (carboxy)methyl cellulose (CMC) were used. The indicators were printed on a plastic foil and covered with a UV curable coating. Data for the kinetic study of photocatalytic reduction and oxidation were gathered with reflectance spectrophotometer and the kinetic analysis was based on the change of the indicator's optical density. Both indicators were successfully activated with UVA and both detected oxygen. The rate of oxidation depended on percentual oxygen concentration, increasing with increasing oxygen concentration. The PVAC based indicator was much quicker to detect oxygen than its CMC counterpart, the former having a color change response to oxygen that is easily detected by naked eye in just one minute.

Microwave-assisted green synthesis of silver nanoparticles and chitosan nanocomposites for the removal of reactive blue-19

Microwave-assisted green synthesis of silver nanoparticles and chitosan nanocomposites for the removal of reactive blue-19

Fabrication of Magnetic Chitosan-Benzil Biopolymer with Organoclay for Remazol Brilliant Blue R Dye Removal: a Statistical Modeling and Adsorption Mechanism

Fabrication of Magnetic Chitosan-Benzil Biopolymer with Organoclay for Remazol Brilliant Blue R Dye Removal: a Statistical Modeling and Adsorption Mechanism

Parabolic trough concentrator design, characterization, and application: solar wastewater purification targeting textile industry dyes and pharmaceuticals—techno-economic study

AbstractSolar energy, along with other renewable resources, has the potential to be a major contributor to solving environmental issues in the future, as illustrated by the most recent advancements in solar photocatalytic technology. Indeed, wastewater treatment using a parabolic solar collector for industrial processes is gaining ground owing to improved system performance and economic benefits. The fabricated parabolic trough collector (PTC) incorporates reflective, parabolic panels that focus solar energy onto a transparent tube positioned along the parabolic focal line, where solar-powered photochemical reactions occur. This study investigated the design, implementation, and effectiveness of a concentrated sunlight system for removing industrial dyes and emerging large-use pharmaceutical contaminants in the presence of H2O2 at a small demonstrator scale (10 L/h). A spectrophotometric assessment revealed that subjecting Remazol Brilliant Blue (RBB, 60 ppm) and ciprofloxacin (CIP, 10 ppm) to irradiation in the presence of 0.1 M H2O2 (RBB) or 0.01 M H2O2 (CIP) for 3 h resulted in a degradation rate exceeding 60% and 80%, respectively. Furthermore, the total organic content (TOC) analysis indicates a very high total removal yield for RBB. On these bases, a techno-economic analysis is produced, and economic viability is discussed. The data reveal that the annual costs for water treatment, considering investment, electricity, and catalyst expenses over a 12-month period are significantly lower for our PTC-based prototype than for a comparable artificial UV-based equipment.

Bio-capped multifunctional CuO nanoparticles via Knautia arvensis for dye removal, antibacterial and antifungal efficiency, and molecular docking

Copper oxide nanoparticles (CuONPs) synthesized using Knautia arvensis flower extract in an environmentally friendly and one-step procedure were characterized by UV–vis, FT-IR, SEM and DLS. The in vitro antibacterial and antifungal activities of CuONPs were determined using E. coli, S. aureus and A. niger. In silico antibacterial and antifungal evaluation of CuONPs were performed by molecular docking analysis using chitin deacetylase of A. niger, topoisomerase IV of E. coli and tyrosyl-tRNA synthetase of S. aureus. The best binding energy was determined using these microbial targets in molecular docking analyses and the antimicrobial mechanisms between the microorganism and the CuONP were elucidated. The degradation potential of Remazol brilliant blue R (RBBR) and Napthol blue black (NBB) dyes in the presence of CuONPs were investigated. The peak obtained at 289 nm as a result of UV–vis analysis revealed the presence of CuONPs. The spherical morphology of CuONPs and the particle size varying between 88–289 nm were visualized by SEM. DLS analysis pointed out the mean diameter of CuONPs was 189 nm along with the PDI value of 0.324. The 600 and 595 cm−1 vibrations attained in the FT-IR spectroscopy showed the presence of CuONPs. In addition, the presence of phenolic compounds found in the plant extract responsible for bio-capping of copper ions into CuONPs were enlightened by the FT-IR analysis. Dye degradation activity of CuONPs was found as 69% and 71% using NBB and RBBR at 50 °C in 90 min, respectively. Antifungal and antibacterial interactions of CuONPs with chitin deacetylase of A. niger, topoisomerase IV of E. coli and tyrosyl-tRNA synthetase of S. aureus were analyzed in order to reveal the antimicrobial mechanisms of CuONPs and it was found that CuONPs demonstrate significant interactions with those proteins with binding energies −7.25, −7.14 and −7.89 kcal mol−1, respectively.

Tinospora cordifolia-assisted synthesis of silver ferrite nanoparticles: a multifunctional approach to photocatalytic degradation of reactive blue-13 dye, anti-bacterial efficacy, and antioxidant properties

Tinospora cordifolia-assisted synthesis of silver ferrite nanoparticles: a multifunctional approach to photocatalytic degradation of reactive blue-13 dye, anti-bacterial efficacy, and antioxidant properties

Decolorization of anthraquinone dye by Brevibacillus laterosporus R81 via polysaccharides excreted

AbstractThe aim of this research was to assess the efficacy of different microbial strains in the decolorization of anthraquinone dyes. Strain R81 was obtained from a textile company's wastewater discharge for its remarkable ability to decolorize reactive blue 19 (RB19). By employing physiological and biochemical analyses, along with 16S rRNA gene sequencing, strain R81 was determined to be Brevibacillus laterosporus. After optimization, the decolorization rate achieved a peak of 86.24% over a 48‐h timeframe, utilizing an initial dye concentration of 100 mg L–1. The decolorization capacity of strain R81 was observed to be impeded by heightened levels of salt and temperature in culture solutions, yet remained unaltered when R81 cells were directly introduced into dye solutions. Furthermore, cells that were induced through prior cultivation in a medium containing RB19 demonstrated enhanced efficacy in decolorization compared to noninduced cells. Subsequent analysis indicated that the development of biofilms and the synthesis of polysaccharides by strain R81 were augmented in a concentration‐dependent fashion by RB19. Nevertheless, the decolorization efficacy of R81 was impeded by the existence of sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB), both of which possess the capacity to eliminate polysaccharides. The decolorization capabilities were reinstated by the SDS or CTAB eluent containing polysaccharides, suggesting a reliance on the presence of polysaccharides. The employment of stepwise diethylaminoethyl (DEAE)‐cellulose chromatography and decolorization experiments elucidated the importance of a specific polysaccharide in the decolorization process. This study proposes a bacteria‐derived polysaccharide as a promising remedy for treating dyeing wastewater contaminated with anthraquinones.

Synthesis and photocatalytic properties of zinc-copper bimetallic oxide nanoparticles for removal of reactive blue 19 dye in aqueous suspension

ABSTRACT This research investigates the photocatalytic removal of reactive blue 19 (RB19) dye utilising Zn-Cu (zinc-copper) bimetallic oxide nanocatalysts under UV irradiation. The nanocatalysts were prepared via the co-precipitation technique and thoroughly characterised using different procedures including XRD, FTIR, BET-BJH, FESEM, TEM, and EDX. BET-BJH analysis revealed a specific surface area of 59.774 m2/g for the Zn-Cu bimetallic oxide nanocatalyst. Response surface methodology (RSM) was employed to optimise operational factors such as catalyst amount, pH, H2O2 amount, and UV power, with a quadratic model showing high reliability (R2 = 0.89). Under optimal conditions (4 mg catalyst amount, pH 6.68, 0.42 mL H2O2 dose, 23 W UV power, and 45 min reaction time), the maximum RB19 removal reached 77.14%, increasing to 98.33% after 120 min. The kinetic study revealed a reaction rate constant of 0.884 min−1, indicating efficient removal. Zn-Cu bimetallic oxides demonstrated superior RB19 removal capacity, with only a 5.92% reduction in removal yield after 5 consecutive reuse cycles. This study underscores the potential of Zn-Cu bimetallic oxide nanocatalysts for efficient removal of RB19 dye in suspension media.

Reactive Blue 19 Adsorption on Activated Carbon From Pumpkin (Cucurbita Pepo) Seed Waste: Kinetic, Isotherm and Thermodynamic Studies

In this study, the removal of Reactive Blue 19 dyestuffs in aqueous systems was investigated by adsorption method using activated carbon obtained from the pumpkin seed waste. Activated carbon obtained from pumpkin seed waste functionalized with ZnCl2 was used as an absorbent. Pumpkin seed hydrochar was characterized by FT-IR, SEM, TGA-DTA, BET, and XPS. In the experimental stages, the adsorption equilibrium time was determined as 45 minutes, the adsorbent dosage was 0.8 g and the optimum pH was 6.0. After this step, the adsorption parameters of Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich isotherms were investigated. It has been pointed out that the adsorption process fits better with the Freundlich isotherm model, and the adhesion occurs in a multilayered manner and on a heterogeneous surface. Freundlich and Dubinin-Radushkevich isotherms support that the bonding mechanism is realized by physical interactions. When the kinetic data were evaluated, it was found to be compatible with the pseudo-second-order kinetic model. The thermodynamic parameters of adsorption indicate that the system is endothermic, and the adsorption of Reactive Blue 19 on activated carbon is a spontaneous process.

Immobilization of fungal mycelial and laccase from Trametes hirsuta EDN082 in alginate-cellulose beads and its use in Remazol Brilliant Blue R dye decolorization

In this study, laccase from Trametes hirsuta EDN 082 was immobilized onto alginate-cellulose beads (CAC-L) and employed for the decolorization of Remazol Brilliant Blue R (RBBR) dye. The characterization and decolorization efficiency of the CAC-L beads were compared to immobilized laccase without cellulose (CA-L), immobilized fungal mycelia (CAC-FM), alginate-cellulose (CAC), and alginate beads (CA), and examined using light microscopy, FTIR, and SEM. The results showed that laccase was successfully immobilized onto alginate-cellulose beads with an enzyme loading of 1.9 U/mL and an immobilization efficiency of 97.7 %. The optimal decolorization (89.2 %) was achieved with 2 g CAC-L beads and 1.9 U/mL laccase activity at 40 °C and pH 5 for 6 h of incubation. Furthermore, the decolorization extent was >70–80 % after five cycles. The phytotoxicity test using Vigna radiata and Artemia salina revealed biodetoxification, indicating that CAC-L beads could be used as a biocatalyst for dye removal.