苦皮藤素在水体中的稳定性及水解产物结构研究

采用高效液相色谱及高效液相色谱-电喷雾多级质谱技术(HPLC-ESI-MS/MS),研究了植物源杀虫活性成分苦皮藤素V、苦皮藤素I、NW28及NW53在不同水体中的稳定性及苦皮藤素Ⅴ在碱性水体中的水解产物。54℃±1℃贮存24 h,在pH值为4的水体中,苦皮藤素V、苦皮藤素I及NW53比较稳定,而NW28稳定性较差,其水解率依次为5.03%、4.15%、6.60%及19.75%;在pH为7的水体中,苦皮藤素V比较稳定,水解率为6.43%,苦皮藤素I、NW28及NW53稳定性较差,水解率分别为12.5%、12.3%及50.55%;在pH为10的水体中,苦皮藤素V、苦皮藤素I、NW28及NW53极易水解,水解率依次为71.53%、84.55%、77.68%及99.30%。苦皮藤素V在碱性水体中的主要水解产物为一系列在其C-1、C-2 C-8及C-9位发生酯键水解而形成的3-羟基、4-羟基或5-羟 基的二氢沉香呋喃多元酯。

Studies on the Stability of Celangulins in Water and theStructures of the Hydrolysates

The stability of the botanical insecticidal components Celangulin V,Celangulin I,NW 28 and NW 53 in three buffer solutions with different pH values at 54℃±1℃ for 24h was studied by high performance liquid chromatography. Celangulin V,Celangulin I and NW 53 were more stable in pH 4 buffer solution,while NW 28 was less stable,the hydrolysis rates of them were 5.03%,4.15%,6.60% and 19.75%,respectively. The stability of four tested compounds in pH 7 buffer solution exhibited similar trend with that of above metioned,and their hydrolysis rates were 6.43%,12.50%,12.03% and 50.55%,respectively. Whereas in pH 10 buffer solution,all tested components were hydrolyzed easily,and their hydrolysis rates were 71.53%,84.55%,77.68% and 99.30%,respectively. The hydrolysates of Celanlulin V were also investigated by means of HPLC-ESI-MS/MS. The results showed that the main hydrolysates were produced from the break of varies ester bonds substituted at C-1,C-2,C-8 and C-9 of the β-dihydroagrofuran sesquiterpene skeleton,in which the structures of five compounds were deduced by their MS/MS spectra.