No abstract

This work looks for a better understanding of the biodegradation of xenobiotic azo dyes mediated by yeasts. During a screening program of phenolic acid assimilating capacities it was found that a non-conventional ascomycetous yeast isolate, identified as Candida oleophila, efficiently decolorizes agar plates supplemented with the commercial textile diazo dye Reactive Black 5. Aerobic batch cultures of C. oleophila could completely decolorize up to 200 mg dye l −1 , an ability not yet reported for this yeast species. Moreover, this performance has been achieved in just 24 h of incubation at 26 • C in the presence of as little as 5 g glucose l −1 and without visible signs of dye adsorption to yeast cells. It was found that decolorization occurs during the exponential growth phase and neither laccase nor manganese-dependent peroxidase activities were detected in the culture medium. As far as the decolorization mechanism is concerned, our results indirectly suggest the involvement of an azoreductase-like activity in azo bonds cleavage.

No abstract

In a previous work the ability of Candida oleophila to use phenolic compounds as sole carbon and energy source at high concentrations without an additional carbon source was reported. C. oleophila grown in bioreactor batch cultures in a diluted and sterilized olive oil mill wastewater (OMW) caused a significant decrease in the total tannins content but no significant alteration was observed in phenolic acid and fatty acid content. Both treated and untreated OMWs were tested to evaluate the capacity in interfering with mitochondrial bioenergetics. Mitochondrial respiration was not affected by treated OMW on the range of used concentrations, contrary to the untreated OMW. Furthermore, mitochondrial membrane potential and respiratory complexes were always significantly less affected by treated OMW in comparison with untreated OMW. However, supplementary treatment should be applied before OMW could be considered non-toxic. r

No abstract

No abstract

No abstract

No abstract