[Degradation of microcystin-RR by ozonation process].

Degradation of algal toxin Microcystin-RR (MC-RR) by ozonation processes was investigated. The degradation rate of MC-RR reached 83.0% at ozone/MC-RR dosage of 6, and the degradation efficiency was decreased with increase of pH or NOM contents. Ozonation byproducts of MC-RR under different ozone dosages were detected by HPLC-MS to elucidate degradation mechanisms and pathways. The results showed that MC-RR degradation by attacking of ozone and hydrogen radicals mainly involved in substitution and cleavage of the Adda conjugated diene structure, cleavage of the peptide bond between Mdha and Ala. And Adda degradation pathway exerted a dominant position during the process.