Quantitative structure-activity relationship study on the biodegradation of acid dyestuffs

摘要

Quantitative structure-biodegradability relationships (QSBRs) were established to develop predictive models and mechanistic explanations for acid dyestuffs as well as biological activities. With a total of four descriptors, molecular weight (M_W), energies of the highest occupied molecular orbital (E_(homo)), the lowest unoccupied molecular orbital (E_(lumo)), and the excited state (E_(es)), calculated using quantum chemical semi-empirical methodology, a series of models were analyzed between the dye biodegradability and each descriptor. Results showed that E_(homo) and M_W were the dominant parameters controlling the biodegradability of acid dyes. A statistically robust QSBR model was developed for all studied dyes, with the combined application of E_(homo) and M_W. The calculated biodegradations fitted well with the experimental data monitored in a facultative-aerobic process, indicative of the reliable prediction and mechanistic character of the developed model.