薄層層析法與經確效高效能薄層層析法測定羅勒中之熊果酸含量   全文下載

Thin-Layer Chromatographic Separation and Validated HPTLC Method for Quantification of Ursolic Acid in Various Ocimum Species

本研究開發並驗證改良之薄層層析法（TLC），檢測羅勒（Ocimum）植株各部位的熊果酸含量。使高效TLC預制板達到最佳分離效果的移動相組成為甲苯：丙酮：甲酸（7.8 : 2.2 : 0.15, v/v/v）。含量和光密度的檢測，需在預制板與甲醇－－硫酸試劑於540 nm反射／吸收等衍生作用之後進行，偵測極限與定量極限分別為20與35 ng/spot。熊果酸濃度在40-440 ng/spot時呈線性，r2 = 0.9995，顯示波峰與濃度具高關聯性。回收率98.36-100.06%，表示方法準確性高。本方法之精準、再現及正確性均已依ICH準則確效。本方法簡單、快速、準確且敏感，可有效的將羅勒中之熊果酸與其他成分分離，並且測定其含量，研究結果顯示，羅勒莖部熊果酸含量最高。"

An improved thin-layer chromatographic separation and quantitative estimation of ursolic acid in different plant parts of various Ocimum species have been developed and validated. Excellent separation of the components was achieved on high-performance precoated TLC plates by using optimized ternary mobile phase consisting of toluene : acetone : formic acid (7.8 : 2.2 : 0.15, v/v/v). Quantification and densitometric determination were performed after derivatization of the plate with methanol-sulphuric acid reagent in reflection/absorption mode at 540 nm. The limit of detection and limit of quantification were found to be 20 and 35 ng/spot, respectively. The response of ursolic acid was linear over the range of 40 to 440 ng/spot with a correlation coefficient of r2=0.9995, indicating good relationship between peak area and concentration. Recovery values from 98.36 to 100.06% showed excellent accuracy of the method. The method was validated according to ICH protocol for precision, repeatability and accuracy. Ursolic acid was efficiently separated from the other components by the proposed method which was very simple, rapid, precise, sensitive and accurate for the quantification of ursolic acid in different plant parts of Ocimum species. The maximum ursolic acid content was found in the stems.