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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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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.
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The effects of sinomenine on intestinal absorption of paeoniflorin by the everted rat gut sac model.(Amsterdam: Elsevier, 2006)Paeoniflorin and sinomenine, derived from the root of Paeonia lactiflora Pall. (family Ranunculaceae) and the stem of Sinomenium acutum Rehder & Wilson (family Menispermaceae), respectively, have been, and are currently, widely used for treatment of rheumatic and arthritic diseases in China and Japan. Our previous studies demonstrated that sinomenine could significantly improve the bioavailability of paeoniflorin in rats, but the underlying mechanisms remain unknown. The present study aims to investigate the intestinal kinetic absorptive characteristics of paeoniflorin as well as the absorptive behavior influenced by co-administration of sinomenine using an in vitro everted rat gut sac model. The results showed a good linear correlation between the paeoniflorin absorption in sac contents and the incubation time from 0 to 90 min. However, the concentration dependence showed that a non-linear correlation exists between the paeoniflorin absorption and its concentrations from 10 to 160 microM, and the absorption was saturated at about 80 microM of the drug. Sinomenine at 16 and 136 microM concentrations could significantly enhance the absorption of paeoniflorin (20 microM) by 1.5- and 2.5-fold, respectively. Moreover, two well-known P-glycoprotein inhibitors, verapamil and quinidine, could significantly elevate the absorption of paeoniflorin by 2.1- and 1.5-fold, respectively. Furthermore, sinomenine in a pattern, which influenced paeoniflorin's absorption, manifested as similar to that of P-glycoprotein inhibitors. In conclusion, sinomenine significantly enhance the intestinal absorption of paeoniflorin, subsequently improve the bioavailability of paeoniflorin. The mechanism underlying the improvement of paeoniflorin's bioavailability was proposed that sinomenine could decrease the efflux transport of paeoniflorin by P-glycoprotein.