Research Abstract |
The biodegradability of various kinds of dyes and their effluent treatment by use of an enzyme, Bilirubin oxidase (BO) are reported. Biodegradation of copper phthalocyanine (CP) was first examined by using the soil perfusion method. An aqueous CP solution was circulated through columns containing native and sterilized field soils, respectively. A rapid decrease to almost zero in both O.D.(λ max=622 nm) and total copper concentration in the solution was observed within 2 weeks in the native soil column, but no significant decrease in the sterilized soil column. A fungus growing on an agar medium containing 0.1% CP as a sole carbon source was isolated from the former column after 292 days of circulation. The fungus was identified as Myrothecium verrucaria according to the characteristic morphology of its phyalides. According to Murao and Tanaka (Agri.Biol.Chem., 1981, 45, 2383), Myrothecium verrucaria isolated from soil generates BO successfully. CP was efficiently decolorized by the BO under the optimum conditions of pH 5-7 and of temperatures 32-37℃. Aqueous solutions of 21 dyes (C.I.Acid Blue 25, 40, 41, 45, 80, 138, Acid Green 25, 27, Reactive Blue 2, 4, 5, 19, Reactive Black 5, Direct Blue 6, 15, 106, Direct Green 59, Direct Black 22, 51, Direct Violet 48, Direct Red 2) were decolorized by BO.The absorption spectrum of decolorized solutions were analysed by HPLC, and their intermediats were detected by the photodiode array analysis.
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