为探索胡椒碱的光致异构化规律,以纯胡椒碱为原料,采用不同辐照时间、辐照波长、光源等处理,HPLC检测胡椒碱及其3种异构体。结果表明:(1)辐照一定时间后,胡椒碱及其异构体相互转化并形成动态平衡;(2)365 nm紫外辐照对胡椒碱异构化的影响大于254 nm辐照;(3)不同光源处理时胡椒碱的损耗量相近,紫外辐照利于异胡椒碱和胡椒脂碱形成,日光灯照射利于异胡椒脂碱形成。

The photoisomerization of piperine solution were investigated by different irradiation conditions such as different time,wavelength and light source.Piperine and its isomers were determined by HPLC.The results showed that(1) piperine and its isomers inter-converted and achieved dynamic balance after irradiated for a certain period of time.(2)The effect of piperine radiated at 365 nm on photoiaomerization was higher than that of 254 nm.(3) The lost of piperine were almost the same when piperine were irradiated with different light sources.UV light benefited the format of chavicine and isopiperine,while sunlight helped more isochavicine being formatted.These results could provide a reference for studying the stability and the retention rate of piperine.