苦荞麦麸皮黄酮类化合物在微波辅助提取过程中的动态变化

Studies on the Chemical Change in the Process of Microwave-Assisted Extraction of Flavonoids from Tartary Buckwheat Bran

利用HPLC-UV和HPLC-ESI-MSn技术,测定了苦荞麦麸皮中黄酮类化合物在微波辅助常压和高压提取过程中化学组分的动态变化,观察提取压力和提取时间对其化学组分的影响。结果表明,在提取压力超过400 kPa时芦丁开始失去1个芸香糖转化为槲皮素;随着微波照射时间的延长,芦丁、表儿茶素和槲皮素提取产率先增加,而后下降;提取压力越大,提取速率越快,分解的速度也越快,达到最高提取产率的时间越短。

In the process of normal pressure and high pressure microwave-assisted extraction, the chemical composition changes of the flavonoids from tartary buckwheat bran were studied by HPLC-UV and HPLC-ESI-MS^n. The influences of pressure and microwave-assisted extraction time on the chemical composition changes were investigated. The experimental results demonstrate that rutin in the extract can be partly decomposed when pressure is over 400 kPa, as a result the content of quercetin increases with the loss of rutinosyl from rutin. With the increase of microwave extraction time, extraction yields of rutin, epicatechin, quercitrin and quercetin firstly increased and then decreased. The higher the pressure is, the faster the extraction rate and the decomposition rate are, the shorter the extraction time for obtaining the highest yield is.