A Study of the Microbial Degradation of Metal Phthalocyanine Textile Dyes by High-performance Liquid Chromatography and Atomic Absorption

Abstract

<jats:p> The investigation of the degradation of two commercially available dyes (Remazol Turquoise Blue and Everzol Turquoise Blue) by the lignin-degrading fungus Phanerochaete chrysosporium and comparison with that of a phthalocyanine whose structure is known (Heligon Blue) are presented. Atomic absorption showed a large release of copper from the biomass at day 7. Polarography served to speciate the copper present in the supernatant. Day 5 sees the complete disappearance of the main dye peak with the release of free copper into the supernatant. Day 7 sees a large increase in the free copper signal with two other electroactive species also present in the supernatant, all of which are seen to decrease at day 8. Visible spectroscopy shows that the main decolourization takes place between day 4 and day 6, with complete decolourization occurring at day 7. HPLC analysis again confirms the above results, with possible degradation products detected at 254 nm occurring at 3.621 and 4.170 min at day 7 which may well correlate with those found in polarographic analysis at –1050 and –1150 mV. Day 7 also sees a large increase in a peak at 2.744 min. </jats:p>

Sulfophthalimide as major metabolite formed from sulfonated phthalocyanine dyes by the white-rot fungusBjerkandera adusta

“…1 and 2), which are likely to originate from the SPC‐core, as the core is identical for both dyes. These two compounds may correspond to the two unidentified metabolites that have recently been reported to occur in the supernatant of SPC dye degradation with P. chrysosporium [13]. For both dyes, further chromatographic signals are recognized at longer retention times (14–22 min; Fig.…”

Sulfophthalimide as major metabolite formed from sulfonated phthalocyanine dyes by the white-rot fungus Bjerkandera adusta

“…1 and 2), which are likely to originate from the SPC-core, as the core is identical for both dyes. These two compounds may correspond to the two unidenti¢ed metabolites that have recently been reported to occur in the supernatant of SPC dye degradation with P. chrysosporium [13]. For both dyes, further chromatographic signals are recognized at longer retention times (14^22 min; Fig.…”

Degradation of natural toxins by phthalocyanines–example of cyanobacterial toxin, microcystin

“…Decrease of 1 O p 2 production during 48 h in all samples could be explained by two processes. The first one is unlikely and includes degradation of phthalocyanines by bacteria during the test period, since microbial degradation of phthalocyanine dyes was reported by Conneely et al (1999). Nevertheless, aseptic conditions were kept during the experiment, thus we consider this explanation is irrelevant.…”