Cr(VI) reduction from contaminated soils by Aspergillus sp. N2 and Penicillium sp. N3 isolated from chromium deposits

The Journal of General and Applied Microbiology

Tsubasa Fukuda¹  Yasuhiro Ishino¹  Hiroshi Morita¹  Akane Ogawa¹  Kadzuyo Tsutsumi¹ 

[1] Graduate School of Environmental Engineering, The University of Kitakyushu

关键词: Aspergillus sp.;    bioremediation;    chromate-resistant fungi;    Cr(VI) removal;    Penicillium sp.;    polluted soils;   

DOI  :  10.2323/jgam.54.295

学科分类：微生物学和免疫学

来源: Applied Microbiology, Molecular and Cellulrar Biosciences Research Foundation

【 摘 要 】

Aspergillus sp. N2 and Penicillium sp. N3 are chromate-resistant filamentous fungi that were isolated from Cr(VI) contaminated soil based on their ability to decrease hexavalent chromium levels in the growth medium. After 120 h of growth in a medium containing 50 ppm Cr(VI) at near neutral pH, Aspergillus sp. N2 reduced the Cr(VI) concentration by about 75%. Penicillium sp. N3 was able to reduce the Cr(VI) concentration by only 35%. However, Penicillium sp. N3 reduced the Cr(VI) concentration in the medium by 93% under acidic conditions. Interestingly, the presence of Cu(II) enhanced the Cr(VI) reducing ability of Aspergillus sp. N2 and Penicillium sp. N3 at near neutral pH. Aspergillus sp. N2 and Penicillium sp. N3 reduced the Cr(VI) concentration in the growth medium to a virtually undetectable level within 120 h. For both Aspergillus sp. N2 and Penicillium sp. N3, mycelial seed cultures were more efficient at Cr(VI) reduction than conidium seed cultures. The mechanisms of Cr(VI) reduction in Aspergillus sp. N2 and Penicillium sp. N3 were enzymatic reduction and sorption to mycelia. Enzymatic activity contributed significantly to Cr(VI) reduction. Aspergillus sp. N2 and Penicillium sp. N3 reduced the levels of Cr(VI) in polluted soil samples, suggesting that these strains might be useful for cleaning up chromium-contaminated sites.

【 授权许可】

Unknown