【摘要】 赤霉素A3(gibberellin A3,GA3)在水溶液中极易异构化为iso-GA3而失去生物活性。本研究利用羟丙基-β-环糊精(hydroxypropyl-β-cyclodextrin,HP-β-CD)对GA3进行包合,采用正交试验设计,确定最优包合条件,以增强GA3在溶液中的稳定性。在此条件下,进一步以溶液中的活性GA3含量为指标,利用豌豆茎伸长生物测试法和超高效液相色谱分析法,对制备的GA3-HP-β-CD进行稳定性检测。结果表明:最优包合条件为n(HP-β-CD)∶n(GA3)=1∶1,在二乙醇胺溶剂(含体积分数20%的吐温-80)中加热至35℃,搅拌2 h,包合率为81.7%;在此条件下,利用紫外可见分光光度法验证了包合物的生成;在(54±2)℃条件下贮藏14 d后,GA3水溶液中的活性GA3几乎全部降解,而GA3-HP-β-CD包合物溶液中GA3的降解率仅为34%。本研究揭示,利用羟丙基-β-环糊精对GA3进行包合,是提高GA3水溶液稳定性的一种有效途径。更多还原

【Abstract】 The isomerization of gibberellin A₃（GA₃） to iso-GA3 in aqueous solutions results in losing biological activity of GA₃.The inclusion compound of GA3 with hydroxypropyl-β-cyclodextrin（HP-β-CD） was prepared in order to enhance the stability and activity of GA3 in aqueous solution.The formation of inclusion compound was detected by the UV spectroscopy.The optimal condition was established by the orthogonal test.The best results was obtained using the mixture of HP-β-CD and GA₃（1:1 mole ratio） stirring for 2 h at 35 ℃ in a diethanolamine solution which contained 20%Tween-80 as the emulsifier.The inclusion rate was 81.7%under the optimal condition.Moreover,the stability of the GA₃-HP-β-CD inclusion complex was evaluated by the biological test on elongation of pea’s stem.The active component of GA₃ in an aqueous solution was quantitated using ultra performance liquid chromatography（UPLC）.Nearly all GA₃ molecules were degraded and lost the biological activity after 14 d at 54℃±2℃.Whereas,the degradation ratio of inclusion compound was only 34%under the same condition.This study showed that the inclusion compound of GA₃ with HP-β-CD might be an effective way to raise GA₃ stability in aqueous solution.更多还原