Comparative behavior of two gram positive Cr6+ resistant bacterial strains Bacillus aerius S1 and Brevibacterium iodinum S2 under hexavalent chromium stress

摘要

Bacillus aerius S1 and Brevibacterium iodinum S2 showed maximum growth at 37?°C and pH 8. B. aerius and B. iodinum could resist Crsup6+/sup upto 30 and 35?mM and biosorption proficiency ( q ) of B. aerius S1 was 19, 27, 52 and 34?mM/g while for B. iodinum S2, it was 39, 50, 23 and 16?mM/g mM/g after 2, 4, 6 and 8 days of incubation. A pronounced rise in antioxidant enzymes activities was determined in B. aerius S1 i.e. POX (963%), CAT (717%), APOX (699%), SOD (683%), and GST (792%). However, in B. iodinum S2, relatively a minor increase was estimated. A significant GSH increase was determined in B. aerius S1 (364%) and B. iodinum S2 (663%) cultures under 2?mM Crsup6+/sup stress. Pilot scale study demonstrated that both strains could reduce Crsup6+/sup into Crsup3+/sup within 6 days from the original tannery effluent with efficiency of 99%.