Removal of Copper (II) Ions from Aqua Growth Medium by Red Yeast

Copper is a natural fungicide and is the active component of various pesticides. We detected uptake of higher concentration of the copper ions and responses to this stress in combination with presence hydrogen peroxide as a source of free radicals were studied on the three red yeast strains of species Rhodotorula glutinis (two strains) and Sporobolomyces roseus (one strain). The maximum Cu sorption was observed at the cells of strain Rhodotorula glutinis CCY 20-2-33 (25,18 mg/g dry weight) and at their exopolymers which accumulated the amount 10.22 mg/g dry weight. The remaining copper was sorbed onto the fibrillar part of cell wall (3.75 mg/g dry weight). The presence peroxide (oxidative stress) in cultivation medium decreased of the toleration of yeasts to Cu2+ ions and cells were able to take up less of about 17 % (from 3mM on 2,5 mM), although total uptake was lower about 11.01-15.96 %. We found that the strains of Rhodotorula glutinis are able to uptake about 44 % more copper ions (25.18-24.32 mg/g dry weight) in compared with strain of Sporobolomyces roseus (16.92 dry weight). However, the addition of peroxide into the cultivation medium the addition of affecting trade changes by reduce of the ability to uptake Cu2+ ions. The exopolymers and fibrillar part of cell wall these yeast were used as biopolymers with high sorption ability for metals.