Bioacumulation and biosorption properties of Penicillium funiculosum against textile dyes

The dye removal properties of Penicillium funiculosum mold were investigated in live and inactive forms. Acid Violet 90 and Direct Blue 86 textile dyes were used as target pollutant molecules. Bioaccumulation occurred when live mold was used. The dyes were gathered by living cells metabolically. The experiments were performed by adding mold spores and dyes to the nutrient medium in an orbital shaker with varied conditions. 100% removal efficiencies were achieved using 100 mg/L dye concentrations at the natural pH of the growth medium (pH 6.7), agitation speed of 160 rpm, 28 °C, and 4 days. The mold was killed in an autoclave for biosorption. The uptake occurred through the interaction of the dye molecules with the functional groups in the cell wall of dead mold. The biosorption experiments were done in batch mode at different pH, time, mixing speed, temperature, dead mold amount, and initial dye concentrations. The removal rates reached ~ 99% for AV90 and ~ 98% for DB86 using 0.1 g of mold at pH 4, 200 rpm shaking speed, 60 min reaction time, and 40 °C with 100 mg/L dye concentrations. The removal percentages were 100% when 0.25 g of mold was used in the same conditions. The kinetic, isotherm, and thermodynamic parameters of the biosorption were calculated. The biosorption is well fitted to the pseudo-second-order kinetic model and Langmuir isotherm. The used mold efficiently removed textile dyes in both live and inactive forms. The uptaken dyes can be seen in the microscope images of the treated molds.