Azo dyes, biodegradation, reactive dyes, bacillus subtilis, rsm. Mniiitmpyp serves as an efficient catalyst for the oxidative degradation of azo dyes such as amaranth by h2o2, which is a simple. Bacterial decolorization and degradation of azo dyes. The anaerobic degradation yields aromatic amines which are mutagenic and toxic to humans and cannot be metabolized further under the conditions which generated them chung and stevens. Biodegradation of carcinogenic textile azo dyes using.
Biodegradation of azo dye using bacillus flexus arun kumar thangavel1 and kokila subbaian2 1department of chemistry, sns college of engineering,coimbatore641107 tamil nadu, india 2department of biochemistry, dr. Biodegradation of reactive red m5b dye using bacillus subtilis. Biodegradation of azo dyes in anaerobicaerobic sequencing. Biodegradation of azo and anthraquinone dyes in continuous. The textile industry accounts for twothirds of the total dyestuff market and during the dyeing process approximately 10% of the dyes used are. Enzymes in azodye degradation microbial degradation of azo dyes is medicated by enzymes. Some azo dyes with this property and which can revert slowly to the trans isomer in the dark are used in sunglasses and car sunroofs. Decolorization of azo dyes direct blue 151 and direct red 31 by. Congo red is one of the best known and used azo dyes which has two azo bonds nn chromophore in its molecular structure. Department of pharmaceutical chemistry, school of advanced sciences, vit university, vellore, tamil nadu, india.
Removal of azo dyes is based on anaerobicaerobic treatment for the reductive cleavage of the azo linkages of dyes and for the degradation of the aromatic amines from azo dye cleavage respectively. Biodegradation of dyes by basidiomycetes fungi using hplc and uvvisible spectrophotometer anuradha kumari. Download it once and read it on your kindle device, pc, phones or tablets. Biodegradation of azo dyes the handbook of environmental chemistry 9 kindle edition by hatice atacag erkurt. Decolorization of dye had positive influence on the growth of. Electrochemical reduction of azo dyes mimicking their. Due to the toxicity, mutagenicity and carcinogenicity of azo dyes and their breakdown products, their removal from industrial wastewaters has been an urgent challenge. Studies on the biodegradation of azo dyes by white rot fungi.
Azo dyes are the main class of industrial dyes and important environmental contaminants. Anaerobic digestion of the azo dyes decomposes due to the cleavage of the azo bond consequently eliminating the color of waste water47. Biodegradation of azo dyes using bacillus megaterium and its phytotoxicity study ii. For those operating under anaerobic conditions, reductive enzyme activities are higher in anoxic conditions, which break down the structure of the synthetic dyes. Accelerating biodegradation of a monoazo dye acid orange 7. The most commercially important are mono azo dyes and di azo dyes, tri azo dyes, whereas poly azo are much less important. Lowcost biodegradation and detoxification of textile azo dye. Biodegradation of acid dyes by an immobilized laccase.
The decolourization of azo dyes has been found to be effective under anaerobic conditions. Reactive red 2 mixed with the anthraquinone dye reactive blue. Biodegradation of mesoporous organosilica nps containing disulfide bonds was examined by tem observation. Crystal violet is one of the vital textile dyes of the triphenylmethane group. Biodegradation of a monoazo dye acid orange 7 ao7 was investigated by using an internal circulation baffled biofilm reactor. In this in this study, toc and salinity also significantly affec ted the distribution of some. Biodegradation of azo dyes by alkaliphilic bacterial consortium is one of the. Biodegradation is a green friendly method used for the degradation of azo dyes. The ftir analysis confirmed that microorganisms were able to degrade toxic azo dyes into a nontoxic product as proved through structural modifications to analyze chemical functions in materials. Due to the toxicity, mutagenicity and carcinogenicity of azo dyes and their breakdown products, their removal from industrial wastewaters has.
The aim was to investigate the fate of the anaerobic ar14 breakdown products aromatic amines during the sbrs aerobic reaction phase. Use features like bookmarks, note taking and highlighting while reading biodegradation of azo dyes the handbook of environmental chemistry 9. Thus, this work aims to i screen and identify azo dye degrading lactic acid bacteria, ii study the potential. Degradation of synthetic azo dyes of textile industry. Azo dyes, their environmental effects, and defining a. The ability of the bioagents to degrade azodyes depends on the structural characteristics of the dye, the temperature and ph of. The biodegradation of azo dyes may occur either aerobically, anaerobic or by a combination of both. Biodegradation and detoxification of azo dyes by some bacterial strains eman zakaria gomaa department of biological and geological sciences, faculty of education, ain shams university, cairo, egypt abstract background and objective.
Biodegradation of textile azo dyes by bacteria isolated from. In mammals, azo dyes are reduced to aryl amines by cytochrome p450 and a flavin dependent cytosolic reductase 4. In this system microbes can acclimatize themselves to toxic wastes and. Azo dyes is the largest group of synthetic colorants and the most usual synthetic dyes released into the environment 2. Dye related parameters such as class and type of azo dye i. Aerobic degradation of the azo dye acid red 151 in a.
Biodegradation products of a sulfonated azo dye in aerobic. Biochemical tests were carried out and identified as. The reduction products aromatic amines should then be further treated using aerobic biological treatment methods 18,4852. The predominant enzymes are azoreductase, laccases, lignin peroxidase, manganese peroxidase, and hydroxylases. Azo dyes contain diazotized amine coupled with an amine or.
Azo dyes account for most textile dyestuf f produced and are most commonly used synthetic dyes in textile industry1. Dissolved oxygen is considered an inhibitor of the azo dye reduction process, since both molecules act as electron acceptors and oxygen is a much stronger oxidant. Oct 10, 2014 microbes and there enzymes could decolorize the dyes by both aerobic and anaerobic metabolis. Its structural stability makes it highly toxic and resistant to biodegradation.
Due to the toxicity, mutagenicity and carcinogenicity of azo dyes. Due to nonfluorescent nature of azo dyes, fluorescent probes are used to track its pathway attached with the azo dye by the alkyl bond. The standard decolorization medium contained glucose as a carbon and energy source, and its ph was either controlled to 5. This study discusses the biodegradation under aerobic conditions of azo dyes with an oxidative enzyme laccase with or without mediator. Degradation of azo dye acid orange 7 in a microbial. The objective of this study was to assess the congo red biodegradation and detoxification by aspergillus niger. Azo dye, biodegradation, decolorization, dyestuff, wastewater, enzymes, microbes introduction there are more than 100,000 different synthetic dyes.
Degradation of azo dye by bacterium, alishewanella sp. The anodic dye degradation products were unstable when exposed. This field has recent origin and grown exponentially over the last two decades. Oct 27, 2011 nowadays combined anaerobicaerobic treatments are considered as the most effective route. Wk4 biodegradation of azo dyes free download as powerpoint presentation. Decolourisation and biodegradation of textile reactive azo dyes by a strain of proteus mirabilis a thesis submitted to the school of postgraduate studies, university of lagos, nigeria in partial fulfillment of the requirements for the award of doctor of philosophy ph. Azo dyes are used in different industries, including textiles, cosmetics, paper, leather, pharmaceuticals, and food, with an annual consumption of about 0. A variety of synthetic dyestuffs released by the textile industry pose a threat to environmental safety. Industrial effluent containing textile dyes is regarded as a major environmental concern in the present world. Bacterial decolorization and degradation of azo dyes under certain environmental conditions has gained momentum as a method of treatment, as these are inexpensive, ecofriendly and can be applied. In addition, detoxification effectiveness of the target dye was also estimated through the microtox test. Biodegradation of azo dyes the handbook of environmental. Azo dyes are characterized by the presence of one or more azo bonds n n connecting aromatic rings.
Azo dyes account for more than 50% of the dyes used in textile processing industries and are the most common synthetic dyes discharged into the environment khouni et al. The first step in the bacterial degradation of azo dyes, in either anaerobic or aerobic conditions, is the reduction of the n n bond. Mixtures of the azo dyes reactive black 5 and reactive red 2 were degraded in batch as well as continuous experiments. In this study, the degradation of azo dyes was carried out by using bacillus species that were isolated from the soil obtained from the textile industry.
Biodegradation of dyes by basidiomycetes fungi using hplc and. Bioremediation, especially through bacteria, is becoming an emerging and important. Aerobic degradation of the azo dye acid red 151 in a sequencing batch bio. Microbial degradation of synthetic dyes in wastewaters springerlink. Usually azo dyes are resistant to biodegradation, but there are chemical and biological systems capable of reducing them. S and disperse red f3bs, using aeromonas hydrophila sk16 and lysinibacillus sphaericus sk. Studies on the biodegradation of azo dyes by white rot fungi daedalea flavida in the absence of external carbon source chhavi rani, asim k. Biodegradation of azo dye compounds premier publishers. Anaerobicanoxic azo dye decolorization by several mixed and pure bacterial cultures have been reported. Introduction textile effluent treatment is of due significance owing to their polluting effects on water bodies1. Biodegradation is a costeffective method to remove the residues of azo dyes prior to their discharge in wastewater streams from dye product industries.
Azo dyes are characterized by one or more azo groups which nitrogen to nitrogen double bond nn and it absorb light in the visible spectrum directly to their chemical structure 3. Studies on immobilized yeast for decolorization of azo dyes dastagir, sindhu sameera, p. In silico analysis of bacterial systems for textile azo. Some dyes combine with metal salts mordanting to form insoluble colored complexes lakes.
Biodegradation of malachite green by the ligninolytic. Biodegradation and detoxification of azo dyes by a newly. Biodegradability of disulfideorganosilica nanoparticles. Azo dyes are the largest group of dyes used in industry ramalho et al. Biodegradation and detoxification of textile azo dyes by. The microorganisms were inoculated from forest residues. Results showed that the yeast named syf1 was identified as candida tropicalis and could decolorize six different azo dyes, among which acid red b arb was decolorized the fastest, mainly through biodegradation. Pdf azo dyes are one of the oldest industrially synthesized organic compounds characterized by presence of azo bond nn and are widely utilized as. Jan 29, 2015 thus, to understand the mechanism of azo dyes degradation by bacterial consortium which doesnt produce aromatic amines under sequential microaerophilicaerobic processes. Efficient oxidative degradation of azo dyes by a water. One of the main problems associated with the treatment of textile wastewater is the removal of dyes. Bacterial decolourization and degradation of azo dye.
Bioremediation of xenobiotics including synthetic dyes by different microbes will hopefully prove a green solution to the problem of environmental soil and water pollution in future. Pdf high throughput sediment dna sequencing reveals azo. There are few reports on the biodegradation of triphenyl methane dyes by bacteria. Azo dyes play an important role as coloring agents in the textile, food, and pharmaceutical industry. The biodegradation of synthetic dyes is an economic, effective, biofriendly, and environmentally benign process.
Biodegradation of azo dyes the handbook of environmental chemistry atacag erkurt, hatice on. Biodegradation of azo dye compounds linkedin slideshare. Biodegradation of azo dyes from wastewater springerlink. Biodegradation and detoxification of azo dyes by some. These materials are usually used for the dyeing of cotton, wool or other protein fiber. Azo dyes play an important role as coloring agents in the textile, food, and. Biodegradation of azo dyes by bacteria inoculated on solid media. Biodegradation of azo dyes the handbook of environmental chemistry. Biodegradation of azo dye compounds irjbb biodegradation of azo dye compounds kamlesh shah department of biotechnology, p. Anaerobic stage is the first step of the treatment process in which azo dyes are reduced, resulting in toxic and colorless aromatic amines. Biodegradation of crystal violet dye by bacteria isolated. Toxicity assessment and microbial degradation of azo dyes. Use of a microbial sensorinhibition effect of azo reactive dyes on activated sludge. They are a commercially important family of azo compounds, i.
This reduction may involve different mechanisms, such as enzymes, low molecular weight redox mediators, chemical reduction by biogenic reductants like sulfide, or a combination of these. Biodegradation of azo dyes by the yeast candida zeylanoides. Many azo dyes, like sudan red and scarlet red, can be used as biological dyes because they are fat soluble and can be absorbed into fat cell tissues on microscope slides. Microbial degradation of basic dyes in wastewaters. About 70% of dyes used in textile industries are azo, a dye complex in structure. At this time, the information related to the biodegradation of dyes other than azo dyes was insignificant. The azo aromatic is the most widespread dye class in the industry. Biodegradation of azo dyes by bacteria inoculated on solid media blanca e. Detoxification and disposal of sludge is a problem to textile dye units. Due to its recalcitrant nature and toxicity for animals and human beings, the elimination of these dyes from the environment is essential. Microbiology research laboratory, department of microbiology, university of chittagong, chittagong 4331, bangladesh available online at.
The initial step in the bacterial degradation of azo dyes is the reductive cleavage of azo bond by an enzymatic biotransformation reaction under static or anaerobic conditions which leads to the formation of colorless aromatic amines. Although many microorganisms can degrade azo dyes 4047 relatively few. These studies confirmed that the nanospheres with a diameter of 40 nm were decomposed into small pieces with a size of 5 nm after incubation for 7 d. Aerobic biodegradation characteristic of different water.
A combination of outer porous eleocharis and inner catalytically active mnpe components of the hybrid resulted in highly efficient sacb system, evidenced by high removal rate of 15 kg m3 day1 100% and complete degradation of toxic orange ii or azo dye into nontoxic products gases and weak acids. The two major sources of release of dyes into the environment are the effluents from textile processing units and dyestuff manufacturing industries oneill et al. Wk4biodegradation of azo dyes free download as powerpoint presentation. The fiber is first treated with an aluminum, chromium and iron salt and then contacted with a lake forming dye azo and anthraquinone derivatives. In textile azo dyes, synthetic dye, reactive dye, acid dye, sulfur dye, basic dye, oxidation dye, anthraquinone dye, acridine dye and many other different colorants are used.
Microbial treatment which involves enzymatic process was very promising for the degradation and detoxification of azo dyes. Azo dyes are the most widely used synthetic colorants in industry and they are regarded as pollutants. Investigation of isolation and immobilization of a microbial consortium for decoloring of azo dye 4bs. For accelerating ao7 biodegradation, endogenous electron donors produced from ao7 by uv photolysis were added into the reactor. Laccase and azoreductase have been shown to degenerate azo dyes rodriguez et al. International journal of chemical and analytical science. Azo dyes account for the majority of all dyestuffs, produced because they are extensively used in the textile, paper, food, leather, cosmetics and pharmaceutical industries. Conclusion azo dyes are the largest and most widely used class of dyes, accounting for 50% of the dyes produced annually. Biodegradation mechanisms and kinetics of azo dye 4bs by a microbial consortium.
About 1015% of dyes goes unused in textile effluents2,3. Decolorization and biodegradation of reactive sulfonated. The optimum growth conditions of the bacterium were 37 c and ph 7 additional file 1. The present study focuses on the biodegradation of such azo dye, malachite green mg, through a potent ligninolytic fungus, aspergillus flavus f10. Read biodegradation of azo dyes by available from rakuten kobo.
Azo dyes are organic compounds bearing the functional group r. However, from the above section, actual removal of ao7 azo dye was achieved figure 1 b. Azo dyes represent the largest and most versatile class of synthetic dyes. Biodegradation of textile azo dyes by bacteria isolated from dyeing industry effluent hassan m. Pdf biodegradation of azo dye compounds researchgate. Azo dyes account for about onehalf of all dyes produced and are the most commonly used synthetic dyes in the textile, food, paper making, color paper printing, leather and cosmetic industries chang and lin2001. Pdf bacterial decolorization and degradation of azo dyes.
The efficacy of this treatment method is highly dependent on establishing. Dye removal from wastewater is a difficult task and expensive2. Wk4biodegradation of azo dyes dye physical sciences. Azo are mainly used in dyeing textile fibers, particularly cotton but also silk, wool, viscose and synthetic fibers. Oct 29, 2014 microbes and there enzymes could decolorize the dyes by both aerobic and anaerobic metabolis. Bacterial decolorization of textile azo dye acid orange by. Received 2nd may 20, revised 27 th june 20, accepted 18 th july 20. Biodegradation of azo dyes hatice atacag erkurt springer. Cleavage of the azo bonds in the azo dyes gives aromatic amines which are more toxic and carcinogenic.
Azo dyes, as groups of electrondeficient xenobiotic compounds, are reported recalcitrant against aerobic bacterial degradation, and aerobic processing of azo dyes has been proven ineffective 23,24,25. Most 6070% of the more than 10,000 dyes applied in textileprocessing industries are azo. Grd college of science, coimbatore641014, tamil nadu, india for correspondence. Sudan dyes may be transformed by anaerobic bacteria in soil, sludge, and the intestines into carcinogenic aromatic amines 22, which exert more toxic health effects than the dyes themselves. Degradation of azo dyes by alcaligenes aquatilis 3c and its potential. Biodegradation of azo dye compounds shah k 007 biological methods bioremediation is the microbial clean up approach is on the front line and priority research area in the environmental sciences. The acute and phytotoxicity evaluation of degraded metabolites suggests that bacterial strain favors the detoxification of dye rb 172. The most widely used dyes in industries are azo dyes, which require an anaerobic and aerobic phases for their complete biodegradation.
All datasets generated for this study are included in the manuscriptsupplementary files. Homology models for laccase and azoreductase enzymes from these two bacteria were. Saturation mutagenesis to improve the degradation of azo. We have examined the decolorization of two azo dyes acid red 88 and acid black 172 by a native trametes villosa laccase immobilized on thiolsulfinateagarose as well as the effect of different redox mediators in the reactions. As stated above, one of the main challenges when using enzymes for the degradation of azo dyes is the diversity of dye structures,,,, but saturation mutagenesis targeting the surface trp environment was able to increase the catalytic efficiency of vp against all three test dyes. Congo red decolorization and detoxification by aspergillus. The aim of this work was to study the degradation and detoxification of three textile azo dyes reactive red 198, reactive red 141 and reactive blue 214 by mixed fungal cultures from semiarid region of brazilian northeast. A number of simple azo dyes was degraded in liquid aerated batch cultures by a strain of the yeast candida zeylanoides. Thus, wb could be utilized as a lowcost growth medium for the enrichment of bacteria and their further use for biodegradation of azo dyes and its derivatives containing wastes into nontoxic form.
This study focused on the biodegradation of an azo dye acid red 14, ar14 in two anaerobicaerobic sequencing batch reactors sbrs treating synthetic textile wastewater, operated with aerobic granular sludge under different hydrodynamic regimens. Biodegradation of synthetic dyes of textile effluent by. The effects of ph, initial dye concentration, temperature. The antibacterial activity was studied of azo dyes. By using certain fungi, eco friendly degradation of azo dyes can be carried out to remove toxicity and thus can help in keeping the environment free from pollution. Degradation of azo dyes in textile dyeing effluent by bacterial consortia. P international journal of environmental sciences volume 1 no. Redox biodegradation of azo dyes universidade do minho. Human health and ecological effects have made this a burning issue. Degradation and detoxification of three textile azo dyes by.
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