Screening, Isolation and Characterization of dye degrading bacteria from textile dye effluents

Textile dye industry waste is one among the foremost serious issues within the atmosphere. The dye wastes are severely harmful to surface water bodies. The dye degradation and decolorisation processes, that embody several physical and chemical strategies having inherent drawbacks, like cost accounting, economically impracticable (require additional energy and chemicals), unable to get rid of a number of the recalcitrant dyes and production of huge quantity of sludge that if not properly treated, successively will cause secondary pollution. So, biological degradation, being eco-friendly and cheap methodology, is taken into account as an efficient methodology for the removal of nephrotoxic radical dyes. Our present study was therefore aimed to isolate dyestuff decolorizing microorganism from dyeing industry effluent associate degreed to check their characteristics so as to use them as an economical bio agent for decolorizing and mineralizing nephrotoxic radical dyes.Various microorganism like Bacillus subtilis, Aeromonas hydrophila and Bacillus Cereus, fungi & actinomycetes are found to possess dye decolorizing activity. For the aim of finding out their characteristics, water sample was subjected to enrichment culture technique and then isolated on sterile nutrient agar plates containing 0.005%, 0.01%, and 1% of Congo red dye. The probable isolated organism from Congo red dye i.e. Pantoea agglomerans was found which can possess the ability to decolorize Congo red at lower concentration. The probable isolates obtained must be additional investigated relating to varied factors like dye degradation capability, media composition affecting dye degradation & mechanism of dye degrading activity.


INTRODUCTION
In modern life, rapid industrialization and urbanization resulted in the discharge of large amount of waste in to the environment, which in turn creates pollution.Water is essential for survival and existence of life on planet earth.The waste water and sewage are released from the industries, that wastes are entering into the water bodies, it is one of major source of environment toxicity [1], it also affect the soil micro flora and aquatic ecosystem [2].The most environmental problem faced due to the textile dyeing industry is that the industry produces large volumes of high strength of aqueous waste effluents.
The discharge of dye effluents containing recalcitrant residue into rivers and lakes [3].The residual dyes from different source such as textile industries, cosmetics, paper mills, pulp industries, dyeing and dye intermediates and bleaching industries, more than 80,000 tons of dyes and pigments are produced in these industries.Especially in textile industries produced more than 70% of the total quantity of waste in India [4].India is the second largest exporter of dyestuffs and intermediates after China.The textile industry accounts for the largest consumption of dyestuffs, at nearly 80%.
The effluent which is untreated is one of the major sources of consumed metal dyes, phenol, aromatic amines [4,5,6]; several aromatic amines are known mutagens and carcinogens to human beings.Dyes also affect internal organ like kidney, liver, gastrointestinal tract.In ancient age natural sources were used for dying clothes.But the extraction process was a bit difficult and also expensive.Hence there was a need of synthetic dyes.In 1856, English chemist William Henry Perkin, in his experiment with aniline (one of the simplest chemical components of coal tar) obtained a black precipitate and discovered purple color, which readily dyed silk and was much more stable in sunlight than any other (natural) purple dye then in use.[7] Dyes are natural or synthetic colored organic compounds having the property of imparting their color to the other substances, such as textile fibers.[7] Synthetic dyes are used extensively for textile dyeing, paper printing, leather dyeing, color photography and as additives in petroleum products because of their ease and cost effectiveness in synthesis, firmness, high stability to light, temperature, detergent and microbial attack and variety in color as compared to natural dyes [8] Approximately, 10,000 different dyes and pigments are used in different industries and their production exceeds over 7 × 10 5 tons annually worldwide [9] "Bioremediation" has become a key microbial tool to deal with different pollutants, is a key research area in the field of environmental science.[11] A number of bacteria, fungi, yeasts, algae and actinomycetes have been capable of decolorizing a range of azo dyes .[12] A number of biological and physico-chemical methods have been developed for the efficient removal of industrial azo dyes.
Particularly, bacteria are the most frequently applied microorganisms for degradation of azo dyes, as they are generally fast to multiply rapidly under aerobic, anaerobic, facultative conditions as well as in extreme environmental conditions, like high salinity and wide variations in both pH and temperature [13]

MATERIALS AND METHODS
The study was conducted at Department of Biotechnology, Smt.Chandibai Himathmal Mansukhani College, Ulhasnagar-3, District Thane, Maharashtra, India.The maximum absorption was noted at 545nm after every 30 minutes .Optical density was noted and a graph was plotted denoting x-axistime in minutes and y-axisoptical density at 545nm.

OBSERVATION AND RESULTS
Textile effluents are directly released into Ulhas River at Ulhasnagar.Thus, only one effluent sample from Ulhas River, Ulhasnagar East was used.

Colony characteristics of selected strains:
Plates containing 0.005%, 0.01% and 1% of Congo red dye with sterile Nutrient agar medium showed growth of colonies which was of 1mm size, circular shape, reddish white color, raised elevation, mucoid consistency, opaque and gram negative which indicated that the bacteria belongs to Coccobacilli genera.

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CONCLUSION
In

2. 1
Sample Collection: Contaminated water samples collected from Ulhas River, Ulhasnagar east were used as a source to isolate bacteria with distinct morphological colony characters capable of decolorizing selected azo dye.The water samples were collected in airtight bottles and filtered through ordinary filter paper to remove large suspended particles and the filtrate were used for the isolation procedure.2.2 Physico-chemical property analysis The collected effluent samples have been analyzed to determine its physico-chemical parameters.The various parameters like Chemical oxygen demand (COD), Biological oxygen demand (BOD), Dissolved Oxygen (DO) were analyzed in the laboratory by the standard protocol.2.3 Enrichment and isolation of dye tolerating strainsa) Enrichment : The water sample collected were subjected to enrichment culture technique.The enrichment was carried out in 100 ml Nutrient Broth medium containing 1% Congo red taken in 250 ml Erlenmeyer flask by adding 10 ml of sample water.The flask was then incubated in a rotary shaker at 50 rpm at 30 0 C for one week.b) Isolation and Characterization of dye degrading bacteria: A loopful from enriched flask was streaked on media plate viz.sterile Nutrient agar with 1% dye concentration Congo red and was incubated at room temperature for 24 hours.Similarly, effluent sample was directly streaked on sterile nutrient agar plates with 0.005% and 0.01% and 1% Congo red and incubated at room temperature for 24 hours.The identification of dye degrading bacterial strains was carried out based on morphological characteristics of colonies obtained on plates.c) Staining and motility: 24 hr.old cultures of all the isolates were used to study Gram reaction and the cell morphology.The morphological characterization of the isolates was checked by Gram's staining.d) Growth curve: 20 ml of sterile nutrient broth was inoculated with 18 hrs.Old culture of 0.005%, 0.01%, 1% concentration of Congo red dye in side arm flask.

Figure 1 :Figure 2 :Figure 3 :
Figure 1: Enrichment of dye degrading bacteria from textile of effluent sample

Figure 4 :Figure 5 :
Figure 4: Growth curve for bacteria grown in 0.01% of Congo Red.
this Investigation, enrichment of dye degrading bacteria in a nutrient agar containing different concentrations of Congo red dye was carried out.After enrichment for 24 hrs.loopful culture was streaked on media plates and incubated for 24 hrs.at R.T. to isolate dye degrading bacterium.Well isolated colonies were found which then studied for their characteristics like cell shape, size, colour, arrangement, etc.By performing Gram's Staining, the Gram nature of all the isolated organisms was found to be Gram negative coccobacilli.The probable organism isolated that decolorizes the Congo red was can be Pantoea agglomerans.As this can be an issue of environmental pollution, the isolates will play a crucial role in the prevention of pollution.It can be concluded that the dye decolorizers are often can be for the treatment of waste water and textile effluents that are alarming for the environment.At future studies, the characterization, optimization and molecular investigation of the dyestuff degradation by the isolate also can provide important info during this field to solve the arising problem.We will able to conjointly develop molecular biology technique and commercially can produce such enzyme to protect environment from the pollution.