Aerobic biodegradation of 2-picolinic acid by a Chryseobacterium sp.

Abstract:

[Background] 2-Picolinic acid is highly toxic, carcinogenic, and long-term persisted in water bodies, thereby further endangers the environment. [Objective] to develop a technique that can efficiently and economically treat 2-picolinic acid-loaded wastewater. [Methods] We isolated a strain that could use 2-picolinic acid as the sole source of carbon, nitrogen and energy under aerobic conditions, and characterized its degradation. [Results] Based on the 16S rRNA gene sequence analysis, this strain was identified as a Chryseobacterium sp. and named as ZD2. When the initial concentration of 2-picolinic acid was 100, 200, 400, 600 and 800 mg/L, ZD2 completely degraded 2-picolinic acid within 10, 18, 22, 78 and 114 h, respectively. Zero-order kinetic model expressed the degradation behavior of 2-picolinic acid by ZD2 well. Between the concentration of 100 and 400 mg/L, the degradation rate constant increased with the increase in concentration and reached the maximum at 400 mg/L. Between the concentration of 600 and 800 mg/L, the degradation rate constant began to decrease, indicating an inhibitory effect. [Conclusion] The degradation efficiency of 2-picolinic acid by ZD2 demonstrates its potential in decontaminating wastewater containing 2-picolinic acid.