Reactive Black 5 bioremoval potential of newly isolated halotolerant Kluyveromyces marxianus

Abstract

Textile industry creates serious amount of dye effluents. These hazardous molecules threat environment, animal, and plants. Therefore, there is an urgent need to diminish the negative effects of these substances. The current study describes reactive dye removal capacities of newly isolated halotolerant yeast. Because of textile wastewaters contain significant amount of salts, 14 yeasts isolates from cheese and pickle factory wastes were screened for their ability to remove different reactive dyes in molasses media contained NaCl. One isolate showed high Reactive Black 5 removal performance in the presence of 4% NaCl (w/v) and this isolate was identified as Kluyveromyces marxianus. Effects of some important parameters such as pH, NaCl concentration, incubation period, inoculum amount, and initial dye concentration on bioremoval efficiency were investigated. K. marxianus was able to remove 70% Reactive Black 5 at an initial dye concentration of 100 mg/L, pH 6 in the presence of 4% NaCl (w/v) and 10% (v/v) inoculum amount. The maximum specific dye uptake (q m) was obtained as 14.8 mg/g when initial dye concentration was 100 mg/L and this value increased to 33.8 mg/g in the presence of 390 mg/L initial dye which is equal to 27.5% removal of the dye. Based on these findings, the current study shows that halotolerant yeast strains can be evaluated for the removal of salt-contained textile wastewaters.