21 research outputs found
<span style="font-size: 20.0pt;mso-bidi-font-size:14.0pt;font-family:"Times New Roman","serif"; color:black">Biodegradation of benzidine based azodyes Direct red and Direct blue by the immobilized cells of <i><span style="font-size:20.5pt; mso-bidi-font-size:14.5pt;font-family:"Times New Roman","serif";color:black">Pseudomonas fluorescens </span></i><span style="font-size:20.0pt;mso-bidi-font-size:14.0pt; font-family:"Times New Roman","serif";color:black">D41 </span></span>
1131-1136<span style="font-size:
14.0pt;mso-bidi-font-size:8.0pt;font-family:" times="" new="" roman","serif";="" color:black"="">Benzidine based azodyes are proven carcinogens, mutagens and have
been linked to bladder cancer of human beings and laboratory animals. The
textile and dyestuff manufacturing industry are the two major sources that
released azodyes in their effluents. The dye, Direct blue contains two
carcinogenic compounds namely benzidine (BZ), 4-amino biphenyl (4- ABP), while
the dye Direct red has benzidine (BZ). Among 40 isolates of Pseudomonas fluorescens <span style="font-size:14.0pt;
mso-bidi-font-size:8.0pt;font-family:" times="" new="" roman","serif";color:black"="">screened,
one isolate designated as D41<span style="font-size:12.0pt;mso-bidi-font-size:
6.0pt;font-family:HiddenHorzOCR;mso-hansi-font-family:" times="" new="" roman";="" mso-bidi-font-family:hiddenhorzocr;color:black"=""> <span style="font-size:
14.0pt;mso-bidi-font-size:8.0pt;font-family:" times="" new="" roman","serif";="" color:black"="">was found to be capable of
extensively degrading the dyes Direct blue and Direct red. Immobilized
cells of <span style="font-size:14.5pt;mso-bidi-font-size:8.5pt;
font-family:" times="" new="" roman","serif";color:black"="">P. fluorescens D41 efficiently degraded Direct red (82%) and Direct blue (71 %)
in the presence of glucose.
</span
Toxicity assessment and microbial degradation of azo dyes
618-626Toxic effluents
containing azo dyes are discharged from various industries and they adversely
affect water resources, soil fertility, aquatic organisms and ecosystem
integrity. They pose toxicity (lethal effect, genotoxicity, mutagenicity and
carcinogenicity) to aquatic organisms (fish, algae, bacteria, etc.) as well as
animals. They are not readily degradable under natural conditions and are
typically not removed from waste water by conventional waste water treatment
systems. Benzidine based dyes have long been recognized as a human urinary
bladder carcinogen and tumorigenic in a variety of laboratory animals. Several
microorganisms have been found to decolourize, transform and even to completely
mineralize azo dyes. A mixed culture of two Pseudomonas
strains efficiently degraded mixture of 3-chlorobenzoate (3-CBA) and
phenol/cresols. Azoreductases of different microorganisms are useful for the
development of biodegradation systems as they catalyze reductive cleavage of
azo groups (-N=N-) under mild conditions. In this review, toxic impacts of
dyeing factory effluents on plants, fishes, and environment, and plausible
bioremediation strategies for removal of azo dyes have been discusse