Bacterial degradation of textile dyes under saline condition
Presented by: Farzana Kausar
IntroductionDyes•A dye is a colored substance that has an affinity to the substrate to which it is being applied. •Amongst the synthetic dyes, azo dyes are the largest group.
Uses
These dyes are widely used in textile, food, cosmetics, pharmaceuticals and paper industry.
Problems cussed by dyes
Chemical nature Pollution Disturb aquatic life Carcinogenic, mutagenic
Biodegradation of textile dyes
Microorganisms Enzymes systemSteps involved in degradationAdvantages
Effects of salt on microbial degradtion
Various salts are used in dyeing industrySalt concentration up to 15-20% High salt concentarion cause plasmolysis Halotolerant micoorganisms
Objective of the study
This study was planned with the following objectives:• Isolation of salt tolerating bacteria from dye contaminated wastewater, sludge and soil.• Evaluate performance of bacteria for the removal of different azo dyes under saline conditions.
MATERIALS AND METHODS Dyes
Reactive Black-5,
Reactive Blue BRS and
Reactive Golden Ovifix
Culture Medium
MSM
pH-7.2
ISOLATION OF AZO DYE DECOLORIZING BACTERIA
1. Sampling Karachi Faisalabad Khewra
2. Isolation Procedure
3. Purification of Bacterial Culture
Table 1: Isolation of salt tolerant bacterial strains Karachi Faisalabad Khewra
Ocean
water Ocean sludge
Noshad textile mill
Qazaffi textile mill
Saline soil of khewra
salt mines KW-1
KW-2
KW-3
KW-4
KW-5
KW-6
KW-7
KW-8
KW-9
KW-10
KW-11
KW-12
KW-13
KW-14
KW-15
KW-16
KW-17
KW-18
KS-1 KS1-19
KS-2 KS-20
KS-3 KS-21
KS-4 KS-22
KS-5 KS-23
KS-6 KS-24
KS-7 KS-25
KS-8 KS-26
KS-9 KS-27
KS-10 KS-28
KS-11 KS-29
KS-12 KS30
KS-13
KS-14
KS-15
KS-16
KS-17
KS-18
F-1 F-19
F-2 F-20
F-3
F-4
F-5
F-6
F-7
F-8
F-9
F-10
F-11
F-12
F-13
F-14
F-15
F-16
F-17
F-18
T-1 T-19
T-2 T-20
T-3 T-21
T-4 T-22
T-5 T-23
T-6 T-24
T-7
T-8
T-9
T-10
T-11
T-12
T-13
T-14
T-15
T-16
T-17
T-18
S-1
S-2
S-3
S-4
S-5
S-6
S-7
S-8
S-9
S-10
SCREENING EFFICIENT BACTERIAL STRAINS FOR DECOLORIZATION OF
AZO DYES •On the basis of better decolorization efficiency initially 16 isolates were selected after 24 hours of decolorization results.
•Three most efficient strains were used for further experiment.
DECOLORIZATION OF AZO DYES UNDER SALINE CONDITIONS
KS-26, KS-23 and T-14 salinity levels ranging from 0-100 g l-1 of NaCl. The medium to inoculum ratio was 20:1. Decolorization of azo dyes
RESULTS
Isolation of salt tolerated bacterial strains
The selected strains of bacteria capable of degrading azo dye at 50 g NaCl l-1
Table 2: The selected strains of bacteria capable of degrading azo dye at 50 g NaCl l-
Bacterial Strains % Decolorization
KS-23 100
KS-26 100
T-14 100
T-17 90
F-9 70
S-4 80
DEGRADATION OF REACTIVE BLACK-5
All the three strains of bacteria were able to decolorize Reactive Black-5 up to salt concentration of 60 g NaCl l-1. The degradation rate was affected with increase in salt concentration
0
20
40
60
80
100
120
0 4 8 12 16 20 24
Time (h)
Deco
lori
zati
on
(%
)
0 10 20 30 40 50 60
Fig. 1: Potential of bacterial strain KS-23 for decolorization of Reactive Black-5 at different salt concentration (0-60 g NaCl l-1)
0
20
40
60
80
100
120
0 4 8 12 16 20 24
Time (h)
Deco
lori
zati
on
(%
)
0 10 20 30 40 50 60
Fig. 2: Potential of bacterial strain KS-26 for decolorization of Reactive Black-5 at different salt concentration (0-60 g NaCl l-1)
0
20
40
60
80
100
120
0 4 8 12 16 20 24
Time (h)
Deco
lori
zati
on
(%
)
0 10 20 30 40 50 60
Fig. 3: Potential of bacterial strain T-14 for decolorization of Reactive Black-5 at different salt concentration (0-60 g NaCl l -1)
DEGRADATION OF REACTIVE BLUE BRS
All the selected strains were able to degrade Reactive Blue BRS efficiently. Bacterial strains were able to tolerate salt concentration up to 100 g NaCl l-1.
0
20
40
60
80
100
120
0 4 8 12 16 20 24
Time (h)
Deco
lori
zati
on
(%
)
0 10 20 30 40 50 60
70 80 90 100
Fig. 4: Potential of bacterial strain KS-23 for decolorization Reactive Blue BRS at different salt concentration (0-100 g NaCl l-1)
0
20
40
60
80
100
120
0 4 8 12 16 20 24
Time (h)
Deco
lori
zati
on
(%
)
0 10 20 30 40 50 60 70
80 90 100
Fig. 5: Potential of bacterial strain KS-26 for decolorization Reactive Blue BRS at different salt concentration (0-100 g NaCl l-1)
0
20
40
60
80
100
120
0 4 8 12 16 20 24
Time (h)
Deco
lori
zati
on
(%
)0 10 20 30 40 50 60
70 80 90 100
Fig. 6: Potential of bacterial strain T-14 for decolorization Reactive Blue BRS at different salt concentration (0-100 g NaCl l-1)
DEGRADATION OF REACTIVE GOLDEN OVIFIX
Bacterial strains were able to decolorize Reactive Golden Ovifix. All the three strains were able to decolorize Reactive Golden Ovifix in the presence of salt concentration 0-60 g NaCl l-1.
0
20
40
60
80
100
120
0 4 8 12 16 20 24
Time (h)
Deco
lori
zati
on
(%
0
0 10 20 30 40 50 60
Fig. 7: Potential of bacterial strain KS-23 for decolorization Reactive Golden Ovifix at different salt concentration (0-100 g NaCl l-1)
0
20
40
60
80
100
120
0 4 8 12 16 20 24
Time (h)
Deco
loriz
ati
on
(%
)0 10 20 30 40 50 60
Fig. 8: Potential of bacterial strain KS-26 for decolorization Reactive Golden Ovifix at different salt concentration (0-100 g NaCl l-1)
0
20
40
60
80
100
120
0 4 8 12 16 20 24
Time (h)
Deco
lori
zati
on
(%
)0 10 20 30 40 50 60
Fig. 9: Potential of bacterial strain T-14 for decolorization Reactive Golden Ovifix at different salt concentration (0-100 g NaCl l-1)
CONCLUSION
This research suggested that under high saline conditions microbial activity is affected but there are many bacteria that have natural ability to tolerate such saline conditions. Therefore use of such halotolerant bacteria can be useful for the degradation of azo dyes under saline conditions.