Research on the Mechanism of Ultrasound To Enhance the Biodegradation of Profenofos by Lactiplantibacillus plantarum

The effect and mechanism of ultrasound on the biodegradation of profenofos by Lactiplantibacillus plantarum were studied in this work. The results showed that ultrasound applied in the prelogarithmic phase of microbial growth would significantly enhance the biodegradation of profenofos (P < 0.05). The key ultrasonic parameters (ultrasonic intensity, pulse mode, and duration time) were optimized using the response surface methodology. The Holden model was used to describe the growth of L. plantarum and the biodegradation of profenofos. Under the optimal ultrasonic condition, the maximum specific growth rate of L. plantarum and the maximum specific degradation rate of profenofos were 2 and 1.7 times higher than those without sonication, respectively. The promotion of profenofos degradation by ultrasound comes from two aspects: one is the enhancement of phosphatase activity; the second is the improvement of cell membrane permeability, which accelerates the transport of nutrients, profenofos, and other metabolites through the cell membrane.