Dissipation of pirimiphos-methyl during wheat fermentation by Lactobacillus plantarum
Dissipation of pirimiphos-methyl during wheat fermentation by Lactobacillus plantarum
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DOI：
10.1111/lam.12128
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发表时间：
2013-11-01
影响因子：
2.4
通讯作者：
Umiljendic, J. S. Gajic
中科院分区：
文献类型：
--
作者：
Dordevic, T. M.;Siler-Marinkovic, S. S.;Umiljendic, J. S. Gajic
研究了植物乳杆菌在小麦发酵过程中对甲基嘧啶的降解规律。采用GC/MS法测定发酵小麦基质中吡嘧磺隆-甲基残留，样品前处理采用25 mL甲醇：丙酮=1：1混合溶剂提取30 min，弗罗里硅土玻璃柱净化，25 mL乙酸乙酯：丙酮=4：1洗脱。以农药降解率最高为目标，采用响应面法对发酵条件进行优化。我们的研究结果表明，植物乳杆菌能够降低小麦中的甲基嘧啶的水平。尽管甲基嘧啶在接种前灭菌期间部分不稳定（类似于37-50%），并且也存在农药的自发化学降解（类似于6-11%），但总体上植物乳杆菌将降解从15%提高到34%，即提高到近81%。此外，研究了甲基吡嘧磺隆对乳酸杆菌生长和发酵效率的影响，其中甲基吡嘧磺隆在高于5 mg kg（-1）的浓度下抑制细菌生长，而甲基吡嘧磺隆的存在总体上不影响乳酸发酵。
In this study, the dissipation of pirimiphos-methyl during wheat fermentation by Lactobacillus plantarum was investigated. Sample preparation for GC/MS detection of pirimiphos-methyl residues from fermented wheat substrate was carried out by two steps: extraction with 25mL of methanol:acetone=1:1 solvent mix for 30min, followed by clean-up procedure through a glass column with florisil coupled with elution by 25mL of ethyl acetate:acetone=4:1. To obtain the highest pesticide degradation level, the fermentation conditions were optimized according to response surface methodology. Our results showed that L.plantarum was able to reduce the level of pirimiphos-methyl in wheat. Although pirimiphos-methyl was partially labile during sterilization prior inoculation (similar to 37-50%), and there was also spontaneous chemical degradation of pesticide (similar to 6-11%), overall L.plantarum enhanced degradation from 15 to 34%, that is, to nearly 81%. Additionally, the effect of pirimiphos-methyl on the lactobacilli growth, and efficiency of fermentation, was studied where pirimiphos-methyl inhibit the growth of bacteria in concentrations higher than 5mgkg(-1), while the presence of pirimiphos-methyl did not overall affect the lactic acid fermentation.