Crowe Kristi M, Bushway Alfred A, Bushway Rodney J, Hazen Russell A
Department of Food Science and Human Nutrition, 5735 Hitchner Hall, University of Maine, Orono, ME 04469-5735, USA.
J Agric Food Chem. 2006 Dec 13;54(25):9608-13. doi: 10.1021/jf0616210.
Chemical and photochemical oxidation processes were evaluated for their ability to degrade residual phosmet on lowbush blueberries and for their role in the conversion of phosmet to phosmet oxon--a toxic metabolite of phosmet. Chemical processes included 1 ppm of aqueous ozone, 1% hydrogen peroxide, 100 ppm of chlorine, and UV, whereas photochemical processes included hydrogen peroxide/UV, chlorine/UV, and ozone/hydrogen peroxide/UV. Phosmet applied as Imidan 2.5EC under laboratory conditions resulted in a mean residual concentration of 44.4 ppm, which was significantly degraded (p < 0.05) by ozone and chlorine, yielding reductions of 57.7 and 46%, respectively. Interaction between phosmet (Imidan 2.5EC) and any chemical or photochemical treatment did not result in conversion to phosmet oxon. Residual analysis of commercially grown blueberries revealed mean phosmet (Imidan 70W) levels of 10.65 ppm and phosmet oxon levels of 12.49 ppm. Treatment of commercial blueberries resulted in significant reductions in phosmet regardless of treatment type; however, only UV, hydrogen peroxide/UV, and ozone treatments degraded phosmet (Imidan 70W) to less toxic metabolites and reduced phosmet oxon levels. Treatment-induced conversion of phosmet to phosmet oxon was noticeably influenced by variations between phosmet formulations. Acceleration of photochemical degradation by UV was not observed. Selective oxidation by ozone represents a significant postharvest process for degrading residual phosmet on lowbush blueberries.
对化学氧化和光化学氧化过程进行了评估，以确定它们降解矮丛蓝莓上残留的稻丰散的能力，以及它们在稻丰散向稻丰散氧磷（稻丰散的一种有毒代谢物）转化过程中所起的作用。化学过程包括1 ppm的臭氧水溶液、1%的过氧化氢、100 ppm的氯以及紫外线，而光化学过程包括过氧化氢/紫外线、氯/紫外线和臭氧/过氧化氢/紫外线。在实验室条件下，以益达胺2.5EC形式施用的稻丰散导致平均残留浓度为44.4 ppm，臭氧和氯对其有显著降解作用（p < 0.05），降解率分别为57.7%和46%。稻丰散（益达胺2.5EC）与任何化学或光化学处理之间的相互作用均未导致其转化为稻丰散氧磷。对商业种植的蓝莓进行残留分析发现，稻丰散（益达胺70W）的平均含量为10.65 ppm，稻丰散氧磷的含量为12.49 ppm。对商业蓝莓进行处理后，无论处理类型如何，稻丰散含量均显著降低；然而，只有紫外线、过氧化氢/紫外线和臭氧处理能将稻丰散（益达胺70W）降解为毒性较小的代谢物，并降低稻丰散氧磷的含量。处理诱导的稻丰散向稻丰散氧磷的转化明显受稻丰散制剂差异的影响。未观察到紫外线对光化学降解的加速作用。臭氧的选择性氧化是矮丛蓝莓采后降解残留稻丰散的一个重要过程。
