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Screening, identification and optimization of a yeast strain, Candida palmioleophila JKS4, capable of azo dye decolorization.

Jafari N, Kasra-Kermanshahi R, Soudi MR - Iran J Microbiol (2013)

Bottom Line: With elongated incubation period, complete decolorization was observed in presence of all dyes.From the physiological properties and phylogenetic analysis based on the 26S rDNA sequences, strain JKS4 was classified into Candida palmioleophila.Because of high decolorizing activity against various azo dyes commonly used in the textile industries, it is proposed that the isolated yeast may have a practical application in the biotransformation of various dye effluents.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology, Faculty of Science, Alzahra University, Tehran, Iran.

ABSTRACT

Background and objectives: Synthetic dyes are recalcitrant to degradation and toxic to different organisms. Decolorization of textile wastewaters is one of the major concerns since last decades. Physical-chemical treatments are very expensive and frequently producing large amounts of toxic wastes. Biological treatments can be more convenient. In the present study, an attempt has been made for decolorization of azo dyes using microbial process.

Material and methods: Screening of microorganisms capable of azo dye decolorization was performed from activated sludge. The decolorization of various dyes (Reactive Black 5, Reactive Orange 16, Reactive Red 198, Direct Blue 71, Direct Yellow 12 and Direct Black 22) was determined by measuring the absorbance of culture supernatant at their λmax. Culture supernatants were also analyzed for UV-Vis absorption between 200-800 nm. The effect of aeration, temperature, different concentrations of glucose and NaCl was studied with an aim to determine the optimal conditions required for maximum decolorization.

Results: The yeast (strain JKS4) which had high ability to decolorize different azo dyes was isolated. Under aerobic condition, the yeast strain showed 85.7% of decolorization at 200 mg/l Reactive Black 5 (as a model azo dye), 1% (w/v) glucose concentration and 35°C after 24 h. All the examined dyes were extensively decolorized (53.35-97.9%) after 24 h. With elongated incubation period, complete decolorization was observed in presence of all dyes. From the physiological properties and phylogenetic analysis based on the 26S rDNA sequences, strain JKS4 was classified into Candida palmioleophila.

Conclusions: Because of high decolorizing activity against various azo dyes commonly used in the textile industries, it is proposed that the isolated yeast may have a practical application in the biotransformation of various dye effluents.

No MeSH data available.


Related in: MedlinePlus

Effect of various glucose concentrations on decolorization of RB5 (at 200 mg/l) by C. palmioleophila JKS4.
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Figure 4: Effect of various glucose concentrations on decolorization of RB5 (at 200 mg/l) by C. palmioleophila JKS4.

Mentions: Fig. 4 shows the effect of different glucose concentrations (0.5-2%) on decolorization of RB5 azo dye at 200 mg/l concentration after 24 h incubation. The decolorization increased from 63.45% to 82.45% with an increase in glucose concentration from 0.5 to 1%. With further increase in glucose concentration to 2%, lower decolorization (79.3%) was obtained. No decolorization was observed when the culture medium was not supplemented with glucose. Fig. 5 shows decolorization of dye (at 200 mg/l concentration) at different temperatures (29, 32, 35 and 40°C) after 24 h incubation. It is clear from the figure that decolorization increased (from 78.3% to 85.7%) with an increase in temperature form 29 to 35°C. The decolorization decreased (to 40%) with further increase in temperature to 40°C. Fig. 6 shows the effect of different NaCl concentrations on decolorization. After 24 h, the decolorization of dye was found to be 82.45, 67.75, 51.9 and 5.5% at NaCl concentrations 0, 3, 5 and 10%, respectively.


Screening, identification and optimization of a yeast strain, Candida palmioleophila JKS4, capable of azo dye decolorization.

Jafari N, Kasra-Kermanshahi R, Soudi MR - Iran J Microbiol (2013)

Effect of various glucose concentrations on decolorization of RB5 (at 200 mg/l) by C. palmioleophila JKS4.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4385174&req=5

Figure 4: Effect of various glucose concentrations on decolorization of RB5 (at 200 mg/l) by C. palmioleophila JKS4.
Mentions: Fig. 4 shows the effect of different glucose concentrations (0.5-2%) on decolorization of RB5 azo dye at 200 mg/l concentration after 24 h incubation. The decolorization increased from 63.45% to 82.45% with an increase in glucose concentration from 0.5 to 1%. With further increase in glucose concentration to 2%, lower decolorization (79.3%) was obtained. No decolorization was observed when the culture medium was not supplemented with glucose. Fig. 5 shows decolorization of dye (at 200 mg/l concentration) at different temperatures (29, 32, 35 and 40°C) after 24 h incubation. It is clear from the figure that decolorization increased (from 78.3% to 85.7%) with an increase in temperature form 29 to 35°C. The decolorization decreased (to 40%) with further increase in temperature to 40°C. Fig. 6 shows the effect of different NaCl concentrations on decolorization. After 24 h, the decolorization of dye was found to be 82.45, 67.75, 51.9 and 5.5% at NaCl concentrations 0, 3, 5 and 10%, respectively.

Bottom Line: With elongated incubation period, complete decolorization was observed in presence of all dyes.From the physiological properties and phylogenetic analysis based on the 26S rDNA sequences, strain JKS4 was classified into Candida palmioleophila.Because of high decolorizing activity against various azo dyes commonly used in the textile industries, it is proposed that the isolated yeast may have a practical application in the biotransformation of various dye effluents.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology, Faculty of Science, Alzahra University, Tehran, Iran.

ABSTRACT

Background and objectives: Synthetic dyes are recalcitrant to degradation and toxic to different organisms. Decolorization of textile wastewaters is one of the major concerns since last decades. Physical-chemical treatments are very expensive and frequently producing large amounts of toxic wastes. Biological treatments can be more convenient. In the present study, an attempt has been made for decolorization of azo dyes using microbial process.

Material and methods: Screening of microorganisms capable of azo dye decolorization was performed from activated sludge. The decolorization of various dyes (Reactive Black 5, Reactive Orange 16, Reactive Red 198, Direct Blue 71, Direct Yellow 12 and Direct Black 22) was determined by measuring the absorbance of culture supernatant at their λmax. Culture supernatants were also analyzed for UV-Vis absorption between 200-800 nm. The effect of aeration, temperature, different concentrations of glucose and NaCl was studied with an aim to determine the optimal conditions required for maximum decolorization.

Results: The yeast (strain JKS4) which had high ability to decolorize different azo dyes was isolated. Under aerobic condition, the yeast strain showed 85.7% of decolorization at 200 mg/l Reactive Black 5 (as a model azo dye), 1% (w/v) glucose concentration and 35°C after 24 h. All the examined dyes were extensively decolorized (53.35-97.9%) after 24 h. With elongated incubation period, complete decolorization was observed in presence of all dyes. From the physiological properties and phylogenetic analysis based on the 26S rDNA sequences, strain JKS4 was classified into Candida palmioleophila.

Conclusions: Because of high decolorizing activity against various azo dyes commonly used in the textile industries, it is proposed that the isolated yeast may have a practical application in the biotransformation of various dye effluents.

No MeSH data available.


Related in: MedlinePlus