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In this study, microcalorimetry combined with chemometric analysis was used to investigate the effects of angle and nail animal valuable drugs on Bacillus subtilis ( B. subtilis) growth. The power-time curves of the growth metabolism of B. subtilis affected by Cornu Cervi Pantotrichum, Cornu Cervi Elaphi, Cornu Saigae Tataricae, cornu caprae hircus, Cornu Bubali, Squama Manis, and Carapax Trionycis were determined using a thermal activity monitor (TAM) air isothermal microcalorimeter, ampoule mode, at 37 °C. By analyzing these curves and some quantitative parameters using principal component analysis, the effects of the seven animal drugs on B. subtilis could be quickly evaluated from the change of the two main parameters, the maximum heat-flow power P and total heat output Q: Cornu Saigae Tataricae, cornu caprae hircus, Cornu Bubali, Squama Manis, and Carapax Trionycis inhibited the growth of B. subtilis, while Cornu Cervi Pantotrichum and Cornu Cervi Elaphi promoted the growth of B. subtilis. Further, the result of hierarchical clustering analysis showed that the drugs which promoted the growth of B. subtilis gathered in one cluster, the other drugs which inhibited the growth of B. subtilis gathered in the other cluster. All these illustrated that the internal characteristics of the seven animal drugs were different though they had similar resources and these drugs could be well clustered according the effects of them on B. subtilis growth with the help of chemometric methods. This study provided an useful idea of the combination of microcalorimetry and chemometric analysis for studying the effects of drugs on organisms. [ABSTRACT FROM AUTHOR]

A simple, sensitive and reliable high-performance liquid chromatography (HPLC) method with evaporative light scattering detection (ELSD) has been developed for simultaneous determination of five major alkaloids in Coptidis rhizoma. Simultaneous separation of five alkaloids was achieved on a Kromasil C18 analytical column (250 mm × 4.6 mm, 5 µm) with the isocratic elution of acetonitrile : water (30 : 70, v/v, the pH was adjusted to 6.0 with 0.2 moL L-1 trichloroacetic acid). The drift tube temperature of the ELSD system was set at 115°C and the nitrogen flow rate was 2.8 L min-1. All the five calibration curves showed a good linear relationship (r2 > 0.9991) within the test ranges. The limit of detections and quantifications for the five alkaloids in ELSD were less than 0.88 and 2.73 ng, respectively. The established method was successfully applied to quantify the five ingredients in different C. rhizoma samples and evaluate the internal quality of C. rhizoma samples from various sources by analysing the chemical fingerprints using similarity analysis (SA), hierarchical clustering analysis (HCA) and principal component analysis (PCA), which provided a useful basis of overall evaluation of the quality of C. rhizoma. [ABSTRACT FROM AUTHOR]

The action of Cornu Cervi Pantotrichum (CCP), Cornu Cervi (CC) and Cornu Saigae Tataricae (CST) on Escherichia coli growth were investigated using microcalorimetry to find the heat change regularity of microbial growth. The similarity of thermogenic curves and thermodynamics parameters were investigated as evaluation index, such as the growth rate constant in the first exponential phase (k1), maximum power in the first exponential phase (P1), maximum power in the secondary exponential phase (P2), peak time in the first exponential phase (T1), peak time in the stationary phase (T2) and the total heat production in stage 1 (Q1), and the total heat production in stage 2 (Q2). Chemometric analysis was used as a reference for the bioactivity evaluation of medicinal animal horns. The results indicated that the similarity between CST and the control was smaller than that between CCP, CC and the control. Both CCP and CC could increase the heat in the microbial growth, whereas CST decreased it. The biotic thermal activity of different medicinal animal horns was objectively, qualitatively, and quantitatively evaluated by the similarity of thermogenic curves and thermodynamics parameters analysis. [ABSTRACT FROM AUTHOR]

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: Musk is a precious and wide applied material in traditional Chinese medicine, also, an important material for the perfume industry all over the world. To establish a rapid, cost-effective and relatively objective assessment for the quality of musk, different musk samples, including authentic, fake and adulterate, were collected. A oxide sensor based electronic nose (E-nose) was employed to measure the musk samples, the E-nose generated data were analyzed by principal component analysis (PCA), the responses of 18 sensors of E-nose were evaluated by loading analysis. Results showed that a rapid evaluation of complex response of the samples could be obtained, in combination with PCA and the perception level of the E-nose was given better results in the recognition values of the musk aroma. The authentic, fake and adulterate musk could be distinguished by E-nose coupled with PCA, sensor 2, 3, 5, 12, 15 and 17 were found to be able to better discriminate between musk samples, confirming the potential application of an electronic instrument coupled with chemometrics for a rapid and on-line quality control for the traditional medicines. [Copyright &y& Elsevier]

Abstract: In the last few years, several fungus infections caused by multidrug-resistant pathogenic agents have got tremendous emergence and prevalence. Screening for novel antifungal agents is in great demand, but traditional microbiological techniques are far from sufficient to meet that requirement. In this study, a non-invasive and non-destructive microcalorimetric method was performed to investigate the antifungal activities of cholic acid (CA) and its derivatives, glycocholic acid (GCA) and taurocholic acid (TCA) on the multiplying and non-multiplying metabolism of Candida albicans. Then, the heat-flow power-time curves of C. albicans growth affected by different concentrations of CA, GCA and TCA were studied by similarity analysis (SA), the quantitative thermokinetic parameters from these curves were analyzed by multivariate analysis of variance (MANOVA) and principal component analysis (PCA). By comparing the values of two main parameters, P 2 (the heat-flow output power of the highest peak) and Q 2 (the heat output of the second exponential growth phase) of C. albicans, it could be found that CA had the strongest antifungal activity among the three steroid compounds, which might be used as a potential antifungal agent in the future. This study provided a useful method and idea of microcalorimetry with chemometrics to efficiently evaluate the antifungal activities of bile acid derivatives, giving some references for screening out new antifungal agents. However, it has to be stressed that all these experiments are carried out in vitro and they still require clinical validation. [Copyright &y& Elsevier]