目的 探讨不同的浸出溶媒、保存温度、煎煮时间及配伍对决明子浸出液紫外吸收光谱的影响。方法 对不同浸出条件下的决明子浸液，用紫外可见分光光度计在190～400nm进行紫外扫描。结果 决明子的水浸液、醇水浸液在278nm处有一吸收峰；而乙醇浸液在此扫描范围无吸收峰，且在237～400nm的吸光度为0。决明子水浸液的室温保存比低温保存的吸光度小。决明子水浸液的吸光度，随着煎煮时间的延长而增加。与夏枯草、菊花和钩藤配伍后，决明子水浸液的紫外吸收光谱形状未发生变化，菊花使其吸光度有所降低，夏枯草和钩藤使其吸光度增加。与黄芩配伍后，决明子水浸液的紫外吸收光谱的形状发生了变化，在207，278，311nm处各有一吸收峰。结论 若决明子水浸液、醇水浸液、乙醇浸液中起降压作用的为同种物质，该物质在237～400nm的吸光度为0。决明子水浸液宜置于冰箱低温保存。从浸出速度和节省能源来考虑，决明子的煎煮时间不宜超过1h。菊花对决明子中化学成分的浸出有抑制作用，夏枯草、钩藤则对其有助溶作用。黄芩不仅影响决明子中化学成分的浸出浓度，而且影响某些化学成分的浸出形态。

Object To study the effects of different solvent, storage temperature, decoction time, and when extracted in combination with other compatible drugs on the UV absorption spectra of cassia seed extract. Methods Extracts of cassia seed obtained under different conditions of extraction were scanned by UV at 190～ 400 nm with a UV-Vis spectrophotometer. Results Aqueous and alcoholic aqueous extracts showed an absorption peak at 278 nm, while an ethanolic extract was devoid of such peak, and its absorbance at 237～ 400 nm was 0. The absorbance of an aqueous extract of cassia seed stored at ambient temperature was lower than that stored at refrigerator temperature, but increased with the time of decoction. The UV spectrum showed no change when cassia seed was extracted in combination with Chrysanthemum morifolium Ramat. , Prunella vulgaris L. or Uncaria rhychophylla (Miq.) Jacks. , but the former decreased, while the latter two increased the absorbance. The UV spectrum showed additional peaks at 207,278, and 311 nm when cassia seed was extracted in combination with Scutellaria baicalensis Georgi. Conclusion If the hypotensive activity of aqueous, alcoholic aqueous, and ethanolic ex tracts of cassia seed was due to a similar constiuent, its absorbance at 237～400 nm must be 0. Aqueous extract of cassia seed should be stored at a low refrigerator temperature. Considering the dissolution rate with heat energy expenditure, the time for decoction should not exceed 1h. C. morifolium showed an inhibitory effect on the dissolution, while both P. vulgaris and U. rhynchophylla showed solubilizing activities. S. baicalensis not only effected the dissolution of chemical constituent in cassia seed, but also showed a profound influence on the chemical composition of the extract.

陕西省自然科学基金资助项目(99SM74)