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Determination of free and total available ferulic acid in different types of Chinese angelica by high performance liquid chromatography(Taipei City, Taiwan: Bureau of Food and Drug Analysis (BFDA), 2007)Free and conjugated forms of ferulic acid (FA) are generally available in higher plant taxa such as Chinese Angelica (CA, the roots of Angelica sinensis (Oliv.) Diels). These various forms of FA were found readily inter-convertible and the extractable level of each depended on solvent properties and acidity. Extraction efficiency using various pH solutions namely, water, 70% methanol, methanol-formic acid (95:5) and methanol-2% NaHCO3 in water (95:5) was compared. Extractable FA were found varying in samples under neutral solvents extraction, whilst relatively consistent for slightly acidic and alkali solvents which were therefore chosen as the optimal media to extract and determine the reproducible levels of free and total available FA. An accurate and rapid high performance liquid chromatographic (HPLC) analysis was conducted using an Alltima C18 column (5 mum, 4.6 mm i.d. x 250 mm) with a guard column (C18, 5 mum, 4.6 mm i.d. x 7.5 mm) at 30degreesC, eluted with a mixture of 1.0% acetic acid and acetonitrile in a gradient program at a flow rate of 1.0 mL/min and detected at 320 nm. Altogether 20 different types of CA samples including whole root, root head, rootlets, whole root slice, Angelica processed by Chinese yellow wine, and charred Angelica were quantified for free and total available FA. Total available FA was found more abundant than free counterpart with an average ratio of 3.15 (n = 20) in the range of 1.29 to 8.23 for these CA samples. The extraction protocol was proven reliable to quantitatively convert all conjugated FA into its free forms and thereby accurately determined by HPLC method for quality assessment.
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Determination of oleanolic acid in Caulis clematidis armandii by HPLC(ILIB, 2006)OBJECTIVE: To develop an HPLC method for the content determination of oleanolic acid in Caulis clematidis armandii after hydrolysis. METHODS: In the system of HPLC, a Alltima C_(18)(250 mm×4.6 mm,5 μm) column was used with a mixture of methanol-water-acetic acid-triethylamine(89∶11∶0.04∶0.02) as the mobile phase.The measuring wavelength was set at 207 nm.The flow rate was 1.0 ml·min~(-1) and the column temperature maintained at 45 ℃.RESULTS The oleanolic acid peak in chromatograms was completely separated from ...
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The Chinese Quality Of Life Instrument: Development Of A New Health-Related Quality Of Life Instrument Using Factor Analysis And Structural Equation Modeling(The Berkeley Electronic Press, 2006)A new Chinese Quality of Life Instrument (ChQOL) based on the principles of diagnosis and practice in Chinese medicine has been developed. This paper describes the development of the ChQOL instrument using factor analysis and structural equation modeling. An initial pilot version of the 78 items instrument was field tested in a sample 273 subjects recruited from different areas in China. The objective of this study was to determine the factor structure and latent constructs of the ChQOL based on factor analysis. A series of confirmatory factor analysis and structural equation models were used to determine the final model of the ChQOL. The results showed that the application of factor analysis and structural equation modeling is an effective method to develop the new health-related quality of life instrument, ChQOL, even though the practice of Chinese medicine is quite different from the practice of conventional western medicine.