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Abstract: In this study, a non-invasive and non-destructive microcalorimetric method was applied to assess the toxic effects of two Aconitum herbal medicines, Radix Aconitum Kusnezoffii and Radix A. carmichaeli, on the multiplying and non-multiplying metabolism of Shigella dysenteriae. Some crucial information, such as the thermogenic curves and thermo-kinetic parameters including growth rate constant k, inhibitory ratio I and half-inhibitory concentration IC 50, of S. dysenteriae growth affected by the two Aconitum species was obtained. Coupled with chemometric analysis on this information, it could be found that Radix A. Kusnezoffii and Radix A. carmichaeli could be differentiated according to their toxic effects; Radix A. Kusnezoffii with IC 50 of 35.2mg/mL had stronger toxic effect than Radix A. carmichaeli with IC 50 of 49.6mg/mL. This present study shows the effectiveness of combining microcalorimetry and chemometrics for assessing the toxic effects of herbal medicines and other food matrices. [Copyright &y& Elsevier]

Abstract: A reverse phase ultra-performance liquid chromatography coupled with evaporative light scattering detection (UPLC–ELSD) method was successfully established for simultaneous determination of five bile acid derivatives in Calculus Bovis and its medicinal preparations using a Waters Acquity UPLC T3 C18 column (2.1×50mm, 1.8μm) with gradient elution of 0.2% aqueous formic acid and acetonitrile. The influence of liquid flow-rate and column temperature, gas flow-rate and drift tube temperature on resolution was investigated to get the optimized parameters and conditions. This method was validated according to the regulatory guidelines with respect to precision, accuracy and linearity. Under optimum conditions, the five analytes were baseline separated in 11min with detection and quantification limits ranged in 3.0–6.0ng and 6.0–18.0ng, respectively, which provided about a twofold reduction in analysis time and good efficiency and sensitivity by comparing a conventional high performance liquid chromatography (HPLC) method. [Copyright &y& Elsevier]