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Enhanced Bio-Mineralization by Riboflavin Photosensitization and its Significance to Detoxification of Benzo[a]pyrene


In this study, 14C-benzo[a]pyrene (BaP) was chosen as a model compound to investigate if photosensitization by riboflavin enhances the subsequent microbial mineralization of polycyclic aromatic hydrocarbons (PAHs) in natural aquatic environments. After photolysis, BaP showed an increased toxicity to human epithelial cell and natural microbial assemblage. However, BaP mineralization rate in a river water sample containing riboflavin is roughly twice of that without riboflavin after the 2-day incubation. Thus, the results imply that microbial assemblage can mineralize BaP photoproducts to carbon dioxide and a combination of riboflavin photosensitization and microbial degradation could lead to complete detoxification of PAHs.

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This research was supported by the following grants: (1) NIH-SCORE S06GM08047 (to JSU) and (2) U.S. Department of the Army # DAAD 19-01-1-0733 and # W911NF-04-1-0327 to JSU. This project was performed, in part using compounds provided by the National Cancer Institute’s Chemical Carcinogen Reference Standards Repository operated under contract by Midwest Research Institute, No. N02-CB-07008. Authors also appreciate Sean Cook of Department of Biology at JSU for his help in the experiment.

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Correspondence to H. M. Hwang.

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Zhao, X., Zhang, Y., Hu, X. et al. Enhanced Bio-Mineralization by Riboflavin Photosensitization and its Significance to Detoxification of Benzo[a]pyrene. Bull Environ Contam Toxicol 79, 319–322 (2007).

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  • Benzo[a]pyrene
  • Mineralization
  • Photosensitizer
  • Riboflavin