[Show abstract][Hide abstract] ABSTRACT: Angelicae dahuricae radix (Baizhi) is a widely used traditional Chinese medicine, for which the traditional processing method has been sun-drying after harvesting. In recent years this method has been replaced by sulphur-fumigation for the sake of improving its appearance and pest control. Correct identification of sulphur-fumigated Baizhi and rapid finding of appropriate chemical markers for the quality control of Baizhi are of very great importance.
To develop a rapid and efficient method of rapid resolution liquid chromatography (RRLC) combined with chemometrics for discriminating sulphur-fumigated Baizhi and controlling its quality.
The samples were separated on a Zorbax SB-C₁₈-column with a gradient elution programme using methanol and water. The optimal RRLC method was validated in terms of linearity, precision, stability and recovery test. In addition, hierarchical clustering analysis (HCA) and principle component analysis (PCA) were applied to differentiate the different samples.
All the constituents were well separated within 18 min. The results of chemical fingerprinting and quantitative analysis showed that the sulphur-fumigated method obviously destroyed the phytochemical profiles of Baizhi. Moreover, the sun-dried and sulphur-fumigated Baizhi could be clearly separated by HCA and PCA, and the critical markers such as oxypeucedanin and imperatorin accountable for such differences were ultimately screened out.
This study revealed that sulphur-fumigation is an inappropriate approach for processing crude drugs and should be prohibited, and that the proposed RRLC method combined with chemometrics demonstrated an efficient strategy for quality control of Baizhi.
No preview · Article · Jul 2012 · Phytochemical Analysis
[Show abstract][Hide abstract] ABSTRACT: To develop an HPLC method for determination of loganin in Pterocephalus hookeri.
The analysis was performed on a Welchrom C18 column (4.6 mm x 250 mm, 5 microm) with acetonitrile-water (12:88) as the the mobile phase at a flow rate of 1 mL x min(-1) and the detection wavelength was 240 nm.
The peak areas and injection amounts of loganin had a good linear relationship at the range of 0.06-1.2 microg. The average recovery was 97.0%, and the RSD was 1.4%.
The method is simple, accurate, and can be used for its quality control.
No preview · Article · Dec 2011 · Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica
[Show abstract][Hide abstract] ABSTRACT: To observe the impact of Rhizoma Coptidis (drug-chemical extract parts-components) on 3T3-L1 pre-adipocytes differentiation and adipocytes insulin resistance, and reveal the pharmacodyamic material basis of Rhizoma Coptidis on insulin resistance.
3T3-L1 pre-adipocytes were well cultured, and then induced to differentiate into fat cells by using dexamethasone, 3-isobutyl-1-methyl-xanthine and insulin together, and establish the insulin resistance model. Based on the experience of traditional medicine use, the adipocytes differentiation and the glucose consumption in the cell culture medium were observed independently.
Aqueous extract, different chemical extract fraction and different alkaloid extract from the herb showed inhibitory effects on 3T3-L1 pre-adipocytes differentiation, especially the compound coptisine significantly inhibited the differentiation in the concentration of 16.5 micromol x L(-1), but non-alkaloid extract from the herb promoted cell differentiation significantly in the concentration of 6.0 micromol x L(-1). Each treatment group, especially jatrorrhizine hydrochloride (in the concentration of 10.5 micromol x L(-1)) significantly decreased the concentration of glucose in 3T3-L1 adipocytes culture, at the same time improved insulin resistance. These effects are similar to the role of rosiglitazone maleate.
Rhizoma Coptidis significantly improved insulin resistance, prevented pre-adipocytes differentiation. Its efficacy may be the synergistic effect of various components. Meanwhile, its role in inhibiting differentiation of pre-adipocytes indicates that coptis to increasing glucose uptake dose not cause fat accumulation and weight increasing. This has some clinical significance in the insulin resistance and metabolic syndrome.
No preview · Article · Jul 2010 · Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica