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Present work describes the bioleaching potential of metals from low-grade mining ore containing smithsonite, sphaerocobaltite, azurite and talc as main gangue minerals with adapted consortium of Sulfobacillus thermosulfidooxidans strain-RDB and Thermoplasma acidophilum. Bioleaching potential improved markedly by added energy source, acid preleaching and adaptation of microbial consortium with mixed metal ions. During whole leaching period including acid preleaching stage of 960 h and bioleaching stage of 212 days about 76% Co, 70% Zn, 84% Cu, 72% Ni and 63% Fe leached out.

The characteristics of oils extracted from gamma-irradiated sunflower (Halianthus annuus) and maize (Zea mays) seeds at absorbed doses of 2, 4, 6, 8, and 10 kGy were investigated. Gamma irradiation did not affect the lipid, protein, fiber, and ash contents of neither sunflower nor maize seeds significantly ( p>0.05). No significant changes were observed for the values of refractive index and density between the control and irradiated sunflower and maize oils. Peroxide value, acid value, para-anisidine value, and conjugated dienes and trienes contents increased, while iodine values decreased in the irradiated oils as compared to those of control oils ( p<0.05). A small decrease in the contents of a-, g-, and d-tocopherols of both sunflower and maize oils was noted by radiation treatment up to 6 kGy, however, the decline was more pronounced at higher dosages. The effects of irradiation on the fatty acid composition of sunflower oil showed a significant ( p<0.05) change in the amounts of stearic, oleic, and linoleic acids, while the concentration of palmitic acid was unaffected even at 10 kGy. Similar trends in the fatty acid profile were found for both the sunflower and maize oil.