Effect of selenite on the morphology and respiratory activity of Phanerochaete chrysosporium biofilms

[Display omitted] •Exposure of Phanerochaete chrysosporium biofilms to SeO32− was investigated.•20% decrease in O2 flux occurred in the biofilm upon 24h of SeO32− exposure.•A more compact and less porous hyphal biofilm structure was induced by SeO32−. The temporal and spatial effects of selenite (SeO32−) on the physical properties and respiratory activity of Phanerochaete chrysosporium biofilms, grown in flow-cell reactors, were investigated using oxygen microsensors and confocal laser scanning microscopy (CLSM) imaging. Exposure of the biofilm to a SeO32− load of 1.67mgSeL−1h−1 (10mgSeL−1 influent concentration), for 24h, resulted in a 20% reduction of the O2 flux, followed by a ∼10% decrease in the glucose consumption rate. Long-term exposure (4days) to SeO32− influenced the architecture of the biofilm by creating a more compact and dense hyphal arrangement resulting in a decrease of biofilm thickness compared to fungal biofilms grown without SeO32−. To the best of our knowledge, this is the first time that the effect of SeO32− on the aerobic respiratory activity on fungal biofilms is described.