肉桂药材粉末中桂皮醛与单体桂皮醛肠代谢差异比较

目的:考察并比较桂皮醛单体及肉桂药材粉末中桂皮醛在大鼠小肠黏膜匀浆液中的代谢特性。方法:采用体外温孵法,以HPLC测定桂皮醛和肉桂酸的含量,考察桂皮醛随时间和浓度代谢变化的动力学特征。HPLC条件:采用Diamonsil C18(150 mm×4.6 mm,5μm),以0.1%磷酸-乙腈(70∶30)为流动相,流速1.0 mL.min-1,检测波长280 nm,柱温25℃。结果:桂皮醛在大鼠小肠匀浆液中很不稳定,含量很快降低,主要代谢产物为肉桂酸。随着桂皮醛浓度的增加,桂皮醛降解达到稳定的时间逐渐延长;其降解速率随着桂皮醛浓度的增大而增加,当桂皮醛浓度达到0.4 mg.mL-1之后,降解速率趋稳。对6个浓度桂皮醛的代谢观察,当单体桂皮醛和肉桂粉末供试品溶液中桂皮醛含量相同时,单体桂皮醛较药材粉末的代谢速率快得多,二者差异明显,肉桂酸的生成也具有同样的趋势。而桂皮醛单体在经加热使代谢酶失活的肠匀浆液中随时间和浓度变化较小。结论:肉桂中主要成分桂皮醛很易在大鼠小肠中受酶代谢降解,主要代谢产物是肉桂酸,药材中的桂皮醛因释放缓慢及与代谢酶接触机会少而受到保护,延缓了其在肠中代谢速率。

The intestinal metabolic difference of pure cinnamic aldehyde and in cinnamon powder

Objective:To compare the difference of pure cinnamic aldehyde and cinnamon powder in rat intestine.Methods: Using an in vitro incubated system,the metabolic pharmacokinetic characteristics of cinnamic aldehyde were investigated.The content of cinnamic aldehyde and cinnamic acid in hatch solution were determined by HPLC.HPLC condition:Diamonsil C18(150 mm×4.6 mm,5 μm)was adopted,the mobile phase consisted of 0.1% phosphoric acid-acetonitrile(70∶ 30)at a flow rate of 1.0 mL·min-1,the detection wavelength was 280 nm and the column temperature was 25 ℃.Results:Cinnamic aldehyde was unstable in intestine,and can be easily metabolited into cinnamic acid.The metabolic rate increased gradually with the concentration.When the concentration reached 0.4 mg·mL-1,metabolic rate was going to be unchangeable.Through 6 concentration investigation it was found that pure cinnamic aldehyde can be more easily metabolited than that in cinnamon powder.Two samples had obvious differerce.As control,pure cinnamic aldehyde showed less metabolism in inactive intestine homogenate which was heated at 100 ℃.Conclusion:Cinnamic aldehyde as main constituents of cinnamon can be easily metabolited into cinnamic acid in rat intestine.For the reason of cinnamic aldehyde in cinnamon powder was slower realeased and had less chance to intact with enzyme in rat intestine,its metabolic rate be reduced comparing with pure cinnamic aldehyde.