Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:1.10.3.2 (
laccase
)
4,656
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Bleach plant effluents from the pulp and paper industry generated during bleaching with chlorine-containing chemicals are highly colored and also partly toxic due to the presence of chloro-organics, hence the need for pretreatment prior to discharge. In a rotating biological contactor (RBC) reactor effluent decolorization was studied using Coriolus versicolor, a white-rot fungus and Rhizomucor pusillus strain RM7, a mucoralean fungus. Decolorization by both fungi was directly proportional to initial color intensities. It was found that the extent of decolorization was not adversely affected by color intensity, except at the lowest level tested. It was shown that decolorization of 53 to 73% could be attained using a hydraulic retention time of 23 h. With R. pusillus, 55% of
AOX
were removed compared to 40% by C. versicolor. Fungal treatment with both R. pusillus and C. versicolor rendered the effluent essentially nontoxic. Addition of glucose to decolorization media stimulated color removal by C. versicolor, but not with R. pusillus. Ligninolytic enzymes (manganese peroxidase and
laccase
) were only detected in effluent treated by C. versicolor. It seems that there are definite differences in the decoloring mechanisms between the white-rot fungus (adsorption + biodegradation) and the mucoralean fungus (adsorption). This aspect needs to be investigated in greater detail to verify the mode responsible for the decolorization activity in both types of fungi.
...
PMID:Decolorization of bleach plant effluent by mucoralean and white-rot fungi in a rotating biological contactor reactor. 1623 95
In present study, xylanase and
laccase
were produced in a cost-effective manner up to 10 kg substrate level and evaluated in elemental chlorine free bleaching of Eucalyptus kraft pulp. Compared to the pulp pre-bleached with xylanase (15%) or
laccase
(25%) individually, the ClO2 savings were higher with sequential treatment of xylanase followed by
laccase
(35%) at laboratory scale. The sequential enzyme treatment when applied at pilot scale (50 kg pulp), resulted in improved pulp properties (50% reduced post color number, 15.71% increased tear index) and reduced
AOX
levels (34%) in bleach effluents. The decreased
AOX
level in effluents will help to meet
AOX
discharge limits, while improved pulp properties will be value addition to the paper.
...
PMID:Xylanase and laccase based enzymatic kraft pulp bleaching reduces adsorbable organic halogen (AOX) in bleach effluents: a pilot scale study. 2503 36