TLCS 法测定苦玄参中苦玄参苷 I_A 和 I_B 的含量

Determination of PicfeltarraeninsⅠ_A andⅠ_B in Picria fel-tarrae Lour,with TLCS

目的:采用薄层扫描法测定不同产地苦玄参的根、茎、叶中苦玄参苷 I_A 和 I_B 的含量,为选择优质药材的产地和苦玄参药材的精制提供依据。方法:以甲醇为溶媒,超声提取苦玄参各药用部位,提取物经大孔树脂 D_(101)精制后,点于含1%CMC-Na的硅胶 GF_(254)板上,以氯仿-甲醇-水(4∶1∶0.1)为展开剂展开后,用 CAMAG TLCⅢ型线性扫描仪测定,检测波长为268nm,狭缝尺寸为8mm×0.6mm。结果:苦玄参苷 I_A 的点样量在1.1-5.4μg、苦玄参苷 I_B 在1.0-6.2μg范围内与各自峰面积呈良好的线性关系,r 分别为0.9990和0.9992,加样回收率分别为98.3%和97.5%;在同一产地不同药用部位中,苦玄参苷 I_A 和I_B 的含量:叶中最高,茎中次之,根中最低;在同一药用部位中,叶中苦玄参苷 I_A 含量高于 I_B ,根和茎中苦玄参苷 I_B 含量高于 I_A。结论:本法简便、准确,可作为选择道地药材的一个依据;从苦玄参苷 I_A 和 I_B 的含量来看,可结合必要的药理实验,考虑只以苦玄参的地上部分入药。

Objective:To determine picfeltarraenins I_A and I_B of the leaves,stems,and roots in Picria fel-tarrae Lour.occurring in several regions so as to afford the basis for purchase and processing.Methods:The air-dried parts(leaves,stems,and roots)of picria fel-tarrae were extracted with MeOH by ultrasonic treatment at room tem- perature.The methanol extracts were purified with macroporous resin D_(101),followed by developing on silica gel pre- coated plates containing 1.0% CMC-Na with a mixture of chloroform-methanol-water(4:1:0.1)as eluent. Then,picfeltarraenins I_A and I_B were determined by TLCS,with the detecting wavelength being 268 nm and slit size 8 mm×0.6 mm.Results:The linear ranges of picfeltarraenins I_A and I_B were 1.1-5.4μg and 1.0-6.2μg,and their average recoveries in real samples were 98.3% and 97.5% respectively.Either the content of picfeltarraenin I_A or I_B in leaves was significantly higher than that in stems,and the content latter was higher than that in roots.The content of picfeltarraenin I_A was higher than that of picfeltarraenin I_B in the identical part in leaves,while conversely in stems and roots.Conclusion:TLCS is a simple and accurate method which can be used for authentic identifica- tion of Picriafel-tarrae ;On the basis of the analytic results of picfeltarraenins I_A and I_B,aerial parts of Picria fel -tarrae is recommended to utilize only,if supported by further pharmacological findings.