Degradation Of Iprodione And Procymidone Residue In Strawberry Based On Electron Accelerator Irradiation

Pesticides are a series of chemicals used in agricultural production such as insecticides,fungicides and growth inhibitors.Their effective use plays an important role in the development of agricultural production.At the same time,the accompanying problem of pesticide residues also has a significant threat and impact on the ecological environment and human health.Therefore,the development of an effective technology to treat agricultural products and accelerate the degradation of harmful pollutants is of critical importance for the healthy development of the food industry.Electron beam irradiation is an environmental pollutant treatment method.The high-energy electron beam emitted by electron accelcrator will react with water molecules to produce active particles such as HO-,H-,hydration electrons,H2O2.These particles act on the degraded molecules,causing oxidation,reduction or hydrolysis,etc.The reaction eventually destroys the chemical bond of the target molecule,causing its degration.The electron accelerator irradiation technology can convert non-biodegradable pollutants into degradable substances,and has the functions of improving the biodegradability of pollutants and reducing their toxicity.Therefore,the electron accelerator was used to degrade two kinds of pesticides in strawberry samples.Taking iprodione and procymidone as examples,the feasibility and degradation law of degradation of pesticides by electron accelerator irradiation were explored.Through experimental verification,the irradiation dose for practical application was proposed.The main research findings are as follows1.In the study of the degradation of iprodione,iprodione was qualitatively and quantitatively analyzed by high performance liquid chromatography(HPLC).In the dose range from 0 to 12 k Gy,5,7.5 and 10 mg/L of iprodione water samples were irradiated.In the dose range of 0-12 k Gy,5,7.5 and 10 mg/L of iprodione water samples were irradiated.The results showed that the degradation rate of iprodione samples approached or exceeded 90% when the irradiation dose reached 4 k Gy,and the degradation rate did not increase significantly within the dose range of 4-12 k Gy.Therefore,strawberry samples were treated at an irradiation dose range of 0-4 k Gy.The results showed that the strawberry samples with residual amounts of 0.43,0.50 and 0.57 mg/kg were irradiated with a dose of 4 k Gy.The degradation rate is higher than 65%.Through comprehensive analysis,taking into account the cost of irradiation,the degradation rate of pesticide residues and the protection of food quality,it is considered that the reference dose of electron accelerator to degrade iprodione in strawberry is 4 k Gy.2.In the study of the degradation of procymidone,the gas chromatography mass spectrometer(GC-MS)was used for qualitative and quantitative analysis.The results showed that the effect of electron accelerators on the degradation of procymidone residues in water and strawberries was significant.Through the analysis of radiation degradation of procymidone pesticides in water and strawberries,the following rules were found: The higher the electron beam irradiation dose,the higher the degradation rate of procymidone pesticides;the same concentration of procymidone,the procymidone concentration the higher,the lower the degradation rate.Residual concentrations of procymidone in the three strawberry samples after spraying were 5.47,10.46 and 15.27 mg/kg,respectively.Under the irradiation treatment of 4 k Gy dose,the degradation rate of procymidone in the three samples was higher than 80%.4 k Gy irradiation dose can effectively reduce the harm of pesticide residues,and will not affect the nutritional composition,freshness and food value of strawberries.