Effects of glucose on the decolorization of Reactive Black 5 by yeast isolates.
The cometabolic roles of glucose were investigated in decolorization of an azo dye, Reactive Black 5, by yeast isolates, Debaryomyces polymorphus and Candida tropicalis. The results indicated that the dye degradation by the two yeasts was highly associated with the yeast growth process and glucose presence in the medium. Color removal of 200 mg dye/L was increased from 76.4% to 92.7% within 60 h to 100% within 18-24 h with the increase of glucose from 5 to 10 g/L, although the activity of manganese dependent peroxidase (MnP) decreased by 2-8 times in this case. Hydrogen peroxide of 233.3 microg/L was detected in 6 h in D. polymorphus culture. The cometabolic functions of glucose and hydrogen peroxide could be also confirmed by the further color removals of 95.8% or 78.9% in the second cycle of decolorization tests in which 7 g glucose/L or 250 microg H2O2/L was superadded respectively together with 200 mg dye/L.
College of Life Sciences, Key Laboratory of Environmental Pollution Control Technology of Henan Province, Henan Normal University, Xinxiang 453007, China. yangqx66@163.com
Qingxiang
Q
Yang
Lingxia
L
Tao
Min
M
Yang
Hao
H
Zhang
D041022:Candida tropicalis / Q000187:drug effects* / Q000378:metabolism; D004396:Coloring Agents / Q000378:metabolism*; D005947:Glucose / Q000494:pharmacology*; D006861:Hydrogen Peroxide / Q000378:metabolism; D009282:Naphthalenesulfonates / Q000378:metabolism*; D010544:Peroxidases / Q000378:metabolism; D004718:Saccharomycetales / Q000187:drug effects* / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000378:metabolism*; D018508:Water Purification
D004396:Coloring Agents; D009282:Naphthalenesulfonates; D014874:Water Pollutants, Chemical; D006861:Hydrogen Peroxide; D010544:Peroxidases; C051129:manganese peroxidase; D005947:Glucose; C063421:Remazol black B