RESUMO
Armand clematis stem (Clematidis Armandii Caulis, Chuanmutong) is a widely used Chinese herb to disinhibit urine and relieve stranguria. It is difficult to be identified owing to its various macroscopic feature and unknown characteristic compounds. Thus, total of 24 Chuanmutong samples and 7 related herbs including four manshurian aristolochia stem (Aristolochiae Manshuriensis Caulis, Guanmutong) and three akebia stem (Akebiae Caulis, Mutong) samples were collected and analyzed in the range of 4 000 - 400 cm⁻¹ by Fourier Transform Infrared (FTIR) and two-dimensional infrared correlation spectroscopy (2D-FTIR) techniques. The FTIR spectra of 24 Chuanmutong samples are consistent in the spectrum profiles, position and intensity of characteristic peaks. 20 of the 24 Chuanmutong samples were randomly selected as calibration samples to calculate and simulate mean spectrum. This mean spectrum is named as FTIR fingerprint of Chuanmutong with characteristic peaks at 3 412, 2 932, 1 739, 1 639, 1 509, 1 456, 1 426, 1 376, 1 332, 1 261, 1 159, 1 035, 897 ,609 cm⁻¹. Meanwhile, the limited level (Mean-3σ=0.992 6) to identify true or false Chuanmutong by correlation coefficient of FTIR spectra was calculated based on the 20 Chuanmutong calibration samples. Then, the rest 4 Chuanmutong, 4 Guanmutong and 3 Mutong samples were used as validation samples to evaluate the identification efficacy. The result shows that the FTIR spectra of 4 Chuanmutong validation samples were similar to the fingerprint. Their correlation coefficients of FTIR spectra were over the limited level and accepted as Chuanmutong. However, the spectra of Guanmutong and Mutong were significantly different from Chuanmutong fingerprint. The correlation coefficients of Guanmutong (0.902 1-0.940 4, n=4) and Mutong (0.954 9-0.978 9, n=3) FTIR spectra were less than the limited level and rejected from Chuanmutong. Furthermore, the number, position and intensity of auto-peaks on the 2D-FTIR were drastically different among the three herbs. It is concluded that the developed FTIR fingerprinting can be rapidly and accurately identify Chuanmutong and differentiate from related herbs.
RESUMO
<p><b>OBJECTIVE</b>To assay ligustilide content in the herb of Szechwan Lovage Rhizome (Chuanxiong, CX), which is the dried rhizome of Ligusticum chuanxiong in order to assess the quality.</p><p><b>METHOD</b>Ligustilide was quantitatively analyzed by high-performance liquid chromatography in 21 CX samples. An Alltima C18 column (4.6 mmx 150 mm, 5 microm) was used as the analytical column. The mobile phase consisted of water and acetonitrile (40:60). The flow rate was maintained at 1.0 mL x min(-1) with the column temperature at ambient conditions. The detection wavelength was set at 350 nm.</p><p><b>RESULT</b>The average content of Z-ligustilide in 21 CX samples was found to be 7.40 +/- 3.54 mg x g(-1)(x +/- s, n = 21). Therefore,the content of Z-ligustilide in CX should not be less than 0.66% (calculated on the dried basis).</p><p><b>CONCLUSION</b>The overall analytical procedure is rapid and accuracy which is considered suitable for the quantitative analysis of ligustilide in CX. The amount of ligustilide in CX samples collected from different cultivation areas was obviously different. However, a relatively higher content of ligustilide was generally found in the CX collected from its main cultivated areas.</p>