Remazol Brilliant Violet Research Articles

Removal of Azo Dyes: Intercalation into Sonochemically Synthesized NiAl Layered Double Hydroxide

A sonochemical method was employed in the synthesis of nickel aluminum layered double hydroxides (NiAl-LDH) and the materials were used as adsorbents for the removal of the reactive azo dye, Remazol Brilliant Violet (RBV-5r). The experimental data obtained for microstructure were compared and both the arrangement and orientation of the intercalated dye species were examined using molecular dynamics (MD) simulations. The obtained materials were characterized by X-ray diffraction (XRD), nitrogen sorption (BET), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA) and Fourier transformation infrared spectroscopy (FTIR). The adsorption characteristics were studied in a batch process by optimizing different parameters such as calcination temperature, contact time, initial dye concentration, solution pH, and solution temperature. NiAl-LDH material synthesized by sonochemical (SC) methods and calcined at 250 °C (NiAl-C250SC) showed the best dye removal effi...

ANTIBODY LABELING WITH REMAZOL BRILLIANT VIOLET 5R, A VINYLSULPHONIC REACTIVE DYE

Colloidal gold is the first choice for labeling antibodies to be used in Point Of Care Testing. However, there are some recent reports on a family of textile dyes—named “reactive dyes”—being suitable for protein labeling. In the present article, protein labeling conditions were optimized for Remazol Brilliant Violet 5R, and the sensitivity of the labeled antibodies was assessed and compared with that of colloidal-gold labeled antibodies. Also, the accelerated stability was explored. Optimal conditions were pH 10.95, dye:Ab molar ratio of 264 and an incubation time of 132 min. Labeled antibodies were stable, and could be successfully used in a slot blot assay, detecting as low as 400 ng/mL. Therefore, the present work demonstrates that vinylsulphonic reactive dyes can be successfully used to label antibodies, and are excellent candidates for the construction of a new generation of Point of Care Testing kits.

Effect of electron donor source on the treatment of Cr(VI)-containing textile wastewater using sulfate-reducing fluidized bed reactors (FBRs)

The treatment of Cr(VI) containing textile wastewater was studied in ethanol and glucose-fed sulfate-reducing fluidized bed reactors at 35°C for around 250days. The synthetic wastewater contained Cr(VI) (5–45mgL−1), azo dye (Remazol Brilliant Violet 5R) (100–200mgL−1), sulfate (2000mgL−1) and ethanol or glucose (2000mgL−1 chemical oxygen demand (COD)). The robustness of two FBRs was assessed under varying Cr(VI) and azo dye loadings. Both reactors performed well in terms of COD, sulfate, color and Cr(VI) removals. However, ethanol-fed FBR performed better than glucose-fed one. The COD, sulfate, chromium and color removals at the highest Cr(VI) concentration (45mgL−1) in ethanol-fed FBR were around 75%, 95%, 93%, and 99%, respectively. Further increase in influent Cr(VI) concentration adversely effected reactor performance. The COD, sulfate, chromium and color removals at 45mgL−1 Cr(VI) in glucose-fed FBR were around 60%, 50%, 93%, and 76%, respectively.

The effect of biological sulfate reduction on anaerobic color removal in anaerobic–aerobic sequencing batch reactors

Combination of anaerobic-aerobic sequencing processes result in both anaerobic color removal and aerobic aromatic amine removal during the treatment of dye-containing wastewaters. The aim of the present study was to gain more insight into the competitive biochemical reactions between sulfate and azo dye in the presence of glucose as electron donor source. For this aim, anaerobic-aerobic sequencing batch reactor fed with a simulated textile effluent including Remazol Brilliant Violet 5R (RBV 5R) azo dye was operated with a total cycle time of 12h including anaerobic (6h) and aerobic cycles (6h). Microorganism grown under anaerobic phase of the reactor was exposed to different amounts of competitive electron acceptor (sulfate). Performance of the anaerobic phase was determined by monitoring color removal efficiency, oxidation reduction potential, color removal rate, chemical oxygen demand (COD), color, specific anaerobic enzyme (azo reductase) and aerobic enzyme (catechol 1,2-dioxygenase), and formation of aromatic amines. The presence of sulfate was not found to significantly affect dye decolorization. Sulfate and azo dye reductions took place simultaneously in all operational conditions and increase in the sulfate concentration generally stimulated the reduction of RBV 5R. However, sulfate accumulation under anaerobic conditions was observed proportional to increasing sulfate concentration.

Effect of nitrate on anaerobic azo dye reduction

The aim of the study was to investigate the effect of nitrate on anaerobic color removal efficiencies. For this aim, anaerobic-aerobic sequencing batch reactor (SBR) fed with a simulated textile effluent including Remazol Brilliant Violet 5R azo dye was operated with a total cycle time of 12 h, including anaerobic (6 h) and aerobic cycles (6 h). Microorganism grown under anaerobic phase of the reactor was exposed to different amounts of competitive electron acceptor (nitrate) and performance of the system was determined by monitoring color removal efficiency, nitrate removal, nitrite formation and removal, oxidation reduction potential, color removal rate, chemical oxygen demand (COD), specific anaerobic enzyme (azo reductase) and aerobic enzyme (catechol 1,2 dioxygenase), and formation and removal of aromatic amines. Variations of population dynamics of microorganisms exposed to various amount of nitrate were identified by denaturing gradient gel electrophoresis (DGGE). It was found that nitrate has adverse effect on anaerobic color removal efficiency and color removal was achieved after denitrification process was completed. It was found that nitrate stimulates the COD removal efficiency and accelerates the COD removal in the first hour of anaerobic phase. About 90 % total COD removal efficiencies were achieved in which microorganism exposed to increasing amount of nitrate. Population dynamics of microorganisms exposed to various amount of nitrate were changed and diversity was increased.

The effect of cyclic anaerobic–aerobic conditions on biodegradation of azo dyes

The effect of cyclic anaerobic-aerobic conditions on the biodegradative capability of the mixed microbial culture for the azo dye Remazol Brilliant Violet 5R (RBV-5R) was investigated in the sequencing batch reactor (SBR) fed with a synthetic textile wastewater. The SBR had a 12-h cycle time with anaerobic-aerobic periods of 3/9, 6/6 and 9/3h. General SBR performance was assessed by measurement of catabolic enzymes (catechol 2,3-dioxygenase, azo reductase), chemical oxygen demand (COD), color and amount of aromatic amines. In this study, under steady-state conditions, the anaerobic period of the cyclic SBR was found to allow the reductive decolorization of azo dye. Longer anaerobic periods resulted in higher color removal efficiencies, approximately 71% for the 3-h, 87% for 6-h and 92% for the 9-h duration. Total COD removal efficiencies were over 84% under each of the cyclic conditions and increased as the length of the anaerobic period was increased; however, the highest color removal rate was attained for the cycle with the shortest anaerobic period of 3h. During the decolorization of RBV-5R, two sulfonated aromatic amines (benzene based and naphthalene based) were formed. Additionally, anaerobic azo reductase enzyme was found to be positively affected with the increasing duration of the anaerobic period; however; it was vice versa for the aerobic catechol 2,3-dioxygenase (C23DO) enzyme.

Characterization of a novel Salmonella Typhimurium chitinase which hydrolyzes chitin, chitooligosaccharides and an N-acetyllactosamine conjugate

Salmonella contain genes annotated as chitinases; however, their chitinolytic activities have never been verified. We now demonstrate such an activity for a chitinase assigned to glycoside hydrolase family 18 encoded by the SL0018 (chiA) gene in Salmonella enterica Typhimurium SL1344. A C-terminal truncated form of chiA lacking a putative chitin-binding domain was amplified by PCR, cloned and expressed in Escherichia coli BL21 (DE3) with an N-terminal (His)(6) tag. The purified enzyme hydrolyzes 4-nitrophenyl N,N'-diacetyl-β-D-chitobioside, 4-nitrophenyl β-D-N,N',N″-triacetylchitotriose and carboxymethyl chitin Remazol Brilliant Violet but does not act on 4-nitrophenyl N-acetyl-β-D-glucosaminide, peptidoglycan or 4-nitrophenyl β-D-cellobioside. Enzyme activity was also characterized by directly monitoring product formation using (1)H-nuclear magnetic resonance which showed that chitin is a substrate with the release of N,N'-diacetylchitobiose. Hydrolysis occurs with the retention of configuration and the enzyme acts on only the β-anomers of chitooligosaccharide substrates. The enzyme also released N-acetyllactosamine disaccharide from Galβ1 → 4GlcNAcβ-O-(CH(2))(8)CONH(CH(2))(2)NHCO-tetramethylrhodamine, a model substrate for LacNAc terminating glycoproteins and glycolipids.

The Effect of Oxygen on Anaerobic Color Removal of Azo Dye in a Sequencing Batch Reactor

AbstractIn this study, various amounts of oxygen were added to the anaerobic phase of an anaerobic‐aerobic sequencing batch reactor (SBR) receiving azo dye remazol brilliant violet 5R to mimic the input of oxygen into the anaerobic zones of biological textile wastewater treatment plants. The effect of oxygen on the anaerobic biodegradative capability of the mixed microbial culture for remazol brilliant violet 5R was investigated. To investigate the effect of oxygen on anaerobic azo dye biodegradation, the anaerobic phase of the SBR cultures were exposed to a very low limited amount of oxygen for various air flow rates. Initially, an air flow rate of 20 mL/min was applied, further on the air flow rate in the anaerobic phase was increased up to 40 mL/min. System performance was determined by monitoring chemical oxygen demand, color removal rate, activities of anaerobic (azo reductase) and aerobic enzymes (catechol 2,3‐dioxygenase, catechol 1,2‐dioxygenase). The results of percentage COD reduction at each stage were similar for all runs, giving an overall reduction of 96%. Anaerobic color removal efficiency and azo reductase activity of anaerobic microorganisms were adversely affected by the addition of oxygen. Color removal efficiencies of the anaerobic phases decreased from 80% down to 42 and 38% for the limited oxygen conditions of 20 mL/min and 40 mL/min, respectively. It was observed that the activity of catechol 2,3‐dioxygenase and catechol 1,2‐dioxygenase, involved in breakage of aromatic rings, increased after they are exposed to oxygen limited conditions compared to fully anaerobic conditions. It was also observed that catechol 1,2‐dioxygenase enzyme activity increased by increasing the oxygen level on oxygen limited conditions in the anaerobic zone.

Treatment of complex Remazol dye effluent using sawdust- and coal-based activated carbons

A complex Remazol dye effluent, comprised of four reactive dyes and auxiliary chemicals, was decolorized using SPS-200 (sawdust-based) and SPC-100 (coal-based) activated carbons. A detailed characterization revealed that the pore diameter of the activated carbon played an important role in dye adsorption. The solution pH had no significant effect on the adsorption capacity in the pH range of 2–10.7. According to the Langmuir model, the maximum uptakes of SPS-200 were 415.4, 510.3, 368.5 and 453.0 mg g −1 for Reactive Black 5 (RB5), Reactive Orange 16 (RO16), Remazol Brilliant Blue R (RBBR) and Remazol Brilliant Violet 5R (RBV), respectively. Conversely, those of SPC-100 were slightly lower, at 150.8, 197.4, 178.3 and 201.1 mg g −1 for RB5, RO16, RBBR and RBV, respectively. In the case of Remazol effluent, SPS-200 exhibited a decolorization efficiency of 100% under unadjusted pH conditions at 10.7, compared to that of 52% for SPC-100.

Poly(methylmethacrylate) grafted chitosan: An efficient adsorbent for anionic azo dyes

Present study reports on peroxydisulfate/ascorbic acid initiated synthesis of Chitosan-graft-poly(methylmethacrylate) (Ch-g-PMMA) and its characterization by FTIR, XRD and 13C NMR. The copolymer remained water insoluble even under highly acidic conditions and was evaluated to be an efficient adsorbent for the three anionic azo dyes (Procion Yellow MX, Remazol Brilliant Violet and Reactive Blue H5G) over a wide pH range of 4–10 being most at pH 7. The adsorbent was also found efficient in decolorizing the textile industry wastewater and was much more efficient than the parent chitosan. Equilibrium sorption experiments were carried out at different pH and initial dye concentration values. The experimental equilibrium data for each adsorbent-dye system were successfully fitted to the Langmuir and Freundlich sorption isotherms. Based on Langmuir model Q max for yellow, violet and blue dyes was 250, 357 and 178, respectively. Thermodynamic parameters of the adsorption processes such as Δ G°, Δ H°, and Δ S° were calculated. The negative values of free energy reflected the spontaneous nature of adsorption. The adsorption kinetic data of all the three dyes could be well represented by pseudo-second-order model with the correlation coefficients ( R 2) being 0.9922, 0.9997 and 0.9862, for direct yellow, reactive violet and blue dye, respectively with rate constants 0.91 × 10 −4, 1.82 × 10 −4 and 1.05 × 10 −4 g mg −1 min −1, respectively. At pH 7, parent chitosan also showed pseudo-second-order kinetics. The temperature dependence of dye uptake and the pseudo-second-order kinetics of the adsorption indicated that chemisorption is the rate-limiting step that controls the process.

Effect of cycle time on biodegradation of azo dye in sequencing batch reactor

The effects of cycle time on the biodegradation of the azo dye remazol brilliant violet 5R (RBV-5R) were investigated in an anaerobic–aerobic sequencing batch reactor (SBR). System performance was determined by monitoring chemical oxygen demand (COD), color, anaerobic enzyme (azo reductase) and aerobic enzyme (catechol 2,3-dioxygenase), and aromatic amine concentration. SBR was operated in three different total cycle times (48 h, 24 h and 12 h), fed with a synthetic textile wastewater. In this study, the anaerobic period of SBR was found to allow the reductive decolorization of azo dye and the aerobic period was found to be effective on further COD removal after the anaerobic period. The percentage reductions in color by the anaerobic stage of the SBR were at 72%, 89% and 86% for the 24-h, 12-h and 6-h cycle times, respectively. Total COD removal efficiencies were over 75% for all operational conditions and about 70% of the COD removal was achieved in the first 3 h of anaerobic stages. During the decolorization of RBV-5R, two sulfonated aromatic amines (benzene-based and naphthalene-based) were formed and detected by HPLC. Aerobic phases of SBR with total cycle times of 48 h, 24 h and 12 h were able to remove benzene-based aromatic amines with removal efficiency of 64%, 92% and 89%, respectively. The results indicated that the best SBR performance in terms of color removal and aromatic amine degradation was achieved from total cycle time of 24 h.

Decolourisation and degradation of textile dyes using a sulphate reducing bacteria (SRB) – biodigester microflora co-culture

Successful decolourisation and degradation of textile dyes was achieved in a biosulphidogenic batch reactor using biodigester sludge from a local municipality waste treatment plant as a source of carbon and microflora that augmented a sulphate reducing bacteria (SRB) consortium. Orange II (O II) was decolourised by 95% within one day (24 h) producing 1-amino-2-naphthol and stoichiometric quantities of sulphanilic acid. The latter was degraded steadily (from
290 to 43 iM) over 20 days while 1-amino-2-naphthol disappeared from the reactor within two days. Other azo dyes, Reactive black 5 (RB 5), Reactive red 120 (RR 120), Remazol Brilliant violet 5R (RBV 5R), an anthraquinone dye Reactive blue 2 (RB 2) and an industrial azo dye mixture (Da Gama Textiles, King Williams Town, South Africa) were successfully degraded with the exception of Amido black 10B (AB 10B). The Orange II degrading cultures were freeze dried to investigate the feasibility of commercialising a powdered mixed starter culture for textile effluent bioremediation, but this decreased the dye degrading efficiency. Therefore bioremediation of textile effluent with sludge and SRB can concomitantly treat two wastes while providing a cheaper alternative of the carbon source. However, the fate of more aromatic amines needs to be investigated before full commercialisation of the process.

Kinetic Studies of Reactive Azo Dye Decolorization in Anaerobic/aerobic Sequencing Batch Reactors

The decolorization kinetics of Remazol Brilliant Violet 5R (RBV-5R) and Remazol Black B (RB-B) (mono- and diazo reactive dyes, respectively) was investigated in the first 9 h (anaerobic phase) of a 24-h cycle anaerobic/aerobic sequencing batch reactor (SBR). Two distinct, successive decolorization periods were observed for both dyes, apparently due to different decolorization mechanisms. The apparent first-order rate constants were much lower for the second periods. First-order kinetics were apparently followed for both periods of RBV-5R but not for the first decolorization period of RB-B, possibly due to the occurrence of mass transfer limitations.

Sequential batch culture studies for the decolorisation of reactive dye by Coriolus versicolor

The white rot fungus Coriolus versicolor could decolorise reactive dye Remazol Brilliant Violet to almost 90%. The fungal mycelia removed color as well as COD up to 95% and 75%, respectively, in a batch reactor. Decolorising activity was observed during the repeated reuse of the fungus. It was possible to substantially increase the dye decolorising activity of the fungus by carefully selecting the operational conditions such as media composition, age of fungus and nitrogen source. The fungal pellets could be used for eight cycles during the long term operation, where medium and dye was replenished at the end of each cycle and the fungus was recycled. Presence of a nitrogen source and nutrient content of media played an important role in sustaining the decolorisation activity of the fungus. The form of nitrogen source (e.g. peptone vs. urea) was also important to maintain the decolorising activity with peptone showing better decolorisation.

Biological sulphate reduction and redox mediator effects on azo dye decolourisation in anaerobic–aerobic sequencing batch reactors

In this work, the anaerobic period of an anaerobic–aerobic sequencing batch reactor was found to allow the reductive decolourisation of azo dyes. 1-l reactors were operated in 24-h cycles comprising anaerobic and aerobic reaction phases, fed with a simulated textile effluent including a reactive type (Remazol Brilliant Violet 5R) or an acid type (Acid Orange 7) azo dye. The aim was to assess the role of different redox phenomena in the anaerobic decolourisation process. Selective inhibition of sulphate reducing bacteria was carried out in the sulphate-containing, reactive dye fed reactor, resulting in nearly complete, though reversible and inhibition of decolourisation. The acid dye fed reactor's supplementation with sulphate, though resulting in sulphate reduction, did not improve decolourisation. Other redox mediators, namely quinones, were more effective in promoting electron transfer to the azo bond. Bio-augmentation of the acid dye fed reactor with a pure sulphate reducer strain known to decolourise azo dyes, Desulfovibrio alaskensis, was also carried out. Decolourisation was improved, but apparently as a result of the carbon source change required to support D. alaskensis growth. A chemically mediated reduction of the azo bond coupled to biological sulphate reduction, thus seemed to account for the high decolourisation yields of both dyes.

Microbial decolorization of reactive azo dyes in a sequential anaerobic–aerobic system

A sequential anaerobic–aerobic treatment process based on mixed culture of bacteria isolated from textile dye effluent-contaminated soil was used to degrade reactive azo dyes Remazol Brilliant Orange 3R. Remazol Black B and Remazol Brilliant Violet 5R. Treating synthetic dye wastewater with the combination anaerobic and aerobic process showed that the majority of colors were removed by the anaerobic process, on the other hand the majority of chemical oxygen demand (COD) was removed in the subsequent aerobic process. Samples from combined anaerobic–aerobic system at the beginning of anaerobic process, after anaerobic process and after subsequent aerobic process were analyzed by high performance liquid chromatography (HPLC). The results suggested that under anaerobic conditions, the azo dyes were reduced and the aromatic amines were generated by the bacterial biomass. After re-aeration of the synthetic dye wastewater, these amines were further degraded by the same isolates. Thus, total degradation of reactive azo dyes was achieved by using an anaerobic–aerobic treatment.

Adsorption of Some Textile Dyes onto Crosslinked Poly(N-Vinylpyrrolidone)

The adsorption of some textile dyes such as Indigosol Blau IBC, Iyozol Turkish G, Iyozol Black B, Remazol Brilliant Orange 3R, Remazol Brilliant Violet 5R, Remazol Blau 3R, Sumufix Red 3BF and Everzol Yellow 4GL with crosslinked poly(N-vinylpyrrolidone) was investigated. Adsorption of these textile dyes onto crosslinked poly(N-vinylpyrrolidone) was studied by batch adsorption techniques at 25°C. The adsorption isotherms obtained were L-type (Langmuir-type) according to the Giles classification system. Adsorption studies indicated that monolayer coverage of the crosslinked poly(N-vinylpyrrolidone) by the dyes studied increased in the order: Indigosol Blau IBC > Iyozol Turkish G > Sumufix Red 3BF > Iyozol Black B > Remazol Brilliant Orange 3R > Remazol Blau 3R > Everzol Yellow 4GL > Remazol Brilliant Violet 5R. Values of the removal efficiency of the dyes ranged from 21% to 81%.

Anaerobic Treatment of Synthetic Textile Wastewater Containing a Reactive Azo Dye

In this study, anaerobic treatment of synthetic textile wastewater containing a reactive azo dye, namely, Remazol Brilliant Violet 5R, was investigated. A fluidized bed reactor (FBR) was used in the study. Before the operation period, start-up of the FBR was completed in 128 days with an immobilized microorganism level of 0.069 g volatile suspended solids per g support material (pumice). Anaerobic treatment of synthetic textile wastewater revealed that 300 mg/L dye was removed in the FBR system. Chemical oxygen demand (COD) and color reduction in the system were approximately 60 and 94%, respectively. Under anaerobic conditions, formation of two sulfonated aromatic amines (SAAs) was detected due to anaerobic reduction of the dye. The SAAs were not degraded under anaerobic conditions. In addition to the anaerobic treatment, the effectiveness of aerobic treatment was investigated in order to further reduce the COD after the anaerobic treatment.

Analysis of secondary metabolite fate during anaerobic‐aerobic azo dye biodegradation in a sequential batch reactor

A great number of the reported examples of azo dye biodegradation comprise two main steps, the reductive cleavage of the azo bond under anaerobic conditions and the subsequent aerobic mineralization of the produced aromatic amines. Based on this possible metabolism a Sequencing Batch Reactor was chosen to study biological color removal from simulated cotton textile effluents containing a reactive azo dye. In previous studies high color removal levels of the azo dye Remazol Brilliant Violet 5R were achieved (up to 90% with an initial dye concentration of 100 mg l−1 ) during the anaerobic phase of Sequencing Batch Reactor operation. However, HPLC analyses revealed that the aromatic amines formed in the anaerobic phase were not mineralized during the subsequent aerobic phase. In an attempt to promote the aerobic biodegradation of these aromatic amines three different approaches were tested, the increase of the relative duration of the aerobic phase, the increase of the hydraulic retention time through the decrease of the daily fill flow and finally the increase of the dye/carbon source concentration ratio through the decrease of the fed volumetric organic load. The two aromatic amines directly resulting from azo bond reduction were detected by HPLC analysis. However, a third metabolite with significant peak area was also detected with a time profile suggesting an equilibrium with one of the aromatic amines. In spite of the conversions occurring between metabolites during the cycles of the tested approaches, no effective biodegradation of these metabolites was observed during the experimental period of over 810 days.

Improved assays for assessment of enzyme activity in nutrient solutions from closed irrigation systems

Colorimetric enzyme assays are suitable for evaluating enzyme activity in nutrient solutions. In this study, variations of the standard methods were tested in order to simplify handling, adapt set-ups to processing large numbers of samples and increase sensitivity of the assays. Hide Powder Azure (HPA) was identified as the most suitable substrate for proteases in nutrient solutions. With this substrate significant higher protease activity was found compared to Gelatin Remazol Brilliant Blue (Gel-RBB), whereas Casein Remazol Brilliant Blue (Cas-RBB) did not show any proteolytic activity. Large number of samples might be treated in a miniaturized set-up in 96-well-microplates. Suitability of assays for chitinolytic, cellulolytic and β-1,3-glucanolytic enzymes was proven in routine tests during 4 weeks. Lyophilization of nutrient solution enhanced the sensitivity of the protease and chitinase assay using Gel-RBB and Chitin Remazol Brilliant Violet, respectively. Compared to the standard assay, concentrated variants showed up to five times higher chitinase and a sixfold increase in protease activity. Due to inconsistent results, no statement concerning cellulase and β-1,3-glucanase is possible. Dissolving the lyophilized residue in water prior to mixing with the enzyme substrate solution is unfavorable for detection of enzyme activity. Dialysis of nutrient solution prior to lyophilization is not essential.