氰戊菊酯的手性拆分及其对映异构体对扁藻的胁迫效应

Chiral separation of fenvalerate and the stress effects of its enantiomers on Platymonas subcordiformis

为减少农药的施放量,有必要对其手性进行研究.选用广谱杀虫剂氰戊菊酯为研究对象,以β-环糊精作为手性选择剂,利用微乳电动毛细管色谱方法,完成氰戊菊酯对映异构体的手性拆分.实验结果表明,在分离电压15 kV,石英毛细管50 cm(有效长度)×75μm(内径),分离温度25℃,β-环糊精浓度30 mmol/L,磷酸二氢钠和硼砂的缓冲溶液pH 6.5,以SDS、正庚烷和正丁醇组成微乳的条件下,可使氰戊菊酯的4个对映体基线分离.利用氰戊菊酯(FEN)和S,S-氰戊菊酯(ESF)对扁藻进行毒理实验,考察了扁藻在胁迫作用下各生理指标,如叶绿素a、可溶性蛋白质、超氧化物歧化酶(SOD)、过氧化物酶(POD)的变化.实验结果表明:氰戊菊酯的96 hEC50为39.2 mg/L,S,S-氰戊菊酯96 hEC50为5.9 mg/L.S,S-氰戊菊酯对扁藻的胁迫作用大于氰戊菊酯消旋体,这在超氧化物歧化酶指标上表现的尤为突出.

It is necessary to study the chiral pesticide to reduce its dosage. A broad spectrum pesticide called fenvalerate （FEN） was selected as an sample, and its four enantiomers were com pletely separated by microemulsion electrokinetic chromato graphy （MEEKC） by using β-eyclodextrin as chiral selector. The separation conditions were as follows：separation voltage t 5. 0 kV, an uncoated fusedsilica capillary 50 cm（effective length） × 75 /ml （inner diameter）, capillary temperature 25 ℃ , con centration of β-cyclodextrin 30 mmol/L, pH 6.5 of the buffer with sodium dihydrogen phosphate and borax, as well as microemulsion with SDS, nheptane and 1butanol. Toxicological ex periments of fenvalerate and S, Sfenvalerate（ESF） to Platy monas subcordiformis were performed, and the physiological in dexes of Platymonas subcordiformis such as chlorophyll a, solu ble protein, superoxide dismutase（SOD） and peroxidase（POD） were evaluated under stress. The 96 hEC50 of fenvalerate is 39.2 mg/L and the 96 hEC50 of S, S-envalerate is 5.9 mg/L, the stress effect of the latter is higher than that of the former. SOD has the maximal reduction rate under such a stress.