Chi-On Chan

Rapid analysis of Radix puerariae by near-infrared spectroscopy

A new, rapid analytical method using near-infrared spectroscopy (NIRS) was developed to differentiate two species of Radix puerariae (GG), Pueraria lobata (YG) and Pueraria thomsonii (FG), and to determine the contents of puerarin, daidzin and total isoflavonoid in the samples. Five isoflavonoids, puerarin, daidzin, daidzein, genistin and genistein were analyzed simultaneously by high-performance liquid chromatography-diode array detection (HPLC-DAD). The total isoflavonoid content was exploited as critical parameter for successful discrimination of the two species. Scattering effect and baseline shift in the NIR spectra were corrected and the spectral features were enhanced by several pre-processing methods. By using linear discriminant analysis (LDA) and soft independent modeling class analogy (SIMCA), samples were separated successfully into two different clusters corresponding to the two GG species. Furthermore, sensitivity and specificity of the classification models were determined to evaluate the performance. Finally, partial least squares (PLS) regression was used to build the correlation models. The results showed that the correlation coefficients of the prediction models are R=0.970 for the puerarin, R=0.939 for daidzin and R=0.969 for total isoflavonoid. The outcome showed that NIRS can serve as routine screening in the quality control of Chinese herbal medicine (CHM).

Mass spectral profiling : An effective tool for quality control of herbal medicines

Abstract Quality control of herbal medicines (HMs) is a big big headache because of the high complexity and unknown mechanism on disease treatment. In this work, mass spectral profiling, a new tool for data processing is proposed to help a lot in solving this problem as gas chromatography–mass spectroscopy (GC–MS) is used to detect both the active and non-active ingredients buried in HMs. The main idea of mass spectral profiling is employment of target m/z points of GC–MS data on the extraction of chromatographic profiles of pure and/or mixed compositions concerned. Further, the absolute or relative abundance at these m/z points can be utilized for results interpretation. With the help of this tool, the qualitative and quantitative information of chemical components within complicated HMs will be mined out effectively. It can then be recommended as reference indices to assess the importance of target compositions in HMs, such as efficacy evaluation on disease treatment of the active constituents. Mass spectral profiling with less data points significantly improves the possibility to get the rich information with no strong requirements of data preprocessing procedures, like alignment of shift of retention times among different chromatographic profiles. It is powerful for quality control of HMs coupled with pattern recognition techniques on high-throughput data sets. In this study, a commonly used herbal medicine, Houttuynia cordata Thunb and its finished injection products, were used to deliver the strategies. Absolutely, the working principles can be extended to the investigation of metabonomics with gas chromatography–time-of-flight–mass spectrometry (GC–MS–TOF). The good performance of mass spectral profiling shows that it can be a promising tool in the future studies of complex mixture systems.

Recent advances in the compound-oriented and pattern-oriented approaches to the quality control of herbal medicines

The current approaches to the quality control of herbal medicines are either compound-oriented or pattern-oriented, the former targeting specific components with some known chemical properties and the latter targeting all detectable components. The marker approach uses specific chemical compounds with known molecular structures, while the multi-compound approach uses both chemical compounds with known structures and those with partial chemical information e.g. retention times, mass spectra and ultraviolet spectra. Apart from chromatographic techniques, new techniques such as oscillating and electrochemistry fingerprints have been developed for quality control. Chemometric resolution methods are widely used for component deconvolution and data comparison. Pattern recognition techniques are used for authentication of herbal medicines.

A Review on the Traditional Chinese Medicinal Herbs and Formulae with Hypolipidemic Effect

Hyperlipidemia, characterized by the abnormal blood lipid profiles, is one of the dominant factors of many chronic diseases such as diabetes, obesity, and cardiovascular diseases (CVD). For the low cost, effectiveness, and fewer side effects, the popularity of using traditional Chinese medicine (TCM) to handle hyperlipidemia is increasing and its role in health care has been recognized by the public at large. Despite the importance of TCM herbs and formulations, there is no comprehensive review summarizing their scientific findings on handling hyperlipidemia. This review summarizes the recent experimental and clinical results of nine representative single Chinese herbs and seven classic TCM formulae that could improve lipid profiles so as to help understand and compare their underlying mechanisms. Most of single herbs and formulae demonstrated the improvement of hyperlipidemic conditions with multiple and diverse mechanisms of actions similar to conventional Western drugs in spite of their mild side effects. Due to increasing popularity of TCM, more extensive, well-designed preclinical and clinical trials on the potential synergistic and adverse side effects of herb-drug interactions as well as their mechanisms are warranted. Hyperlipidemic patients should be warned about the potential risks of herb-drug interactions, particularly those taking anticoagulants and antiplatelet drugs.

Development of an in-line HPLC fingerprint ion-trap mass spectrometric method for identification and quality control of Radix Scrophulariae

Chromatographic fingerprinting has been widely accepted as a crucial method for qualitative and quantitative analyses of bioactives within traditional Chinese medicine. A fingerprint provides detailed information, specific for any given herb, thus facilitating the quality control measures of a given traditional Chinese medicine. In this article, quality assessment of Radix Scrophulariae was achieved by using high performance liquid chromatography combining diode-array detection and electrospray ionization mass spectrometry (HPLC-DAD-ESI/MS). Eight batches of sample obtained from different origins in China were used to establish the fingerprint and quantitative analyses. By comparing the retention times, UV and MS spectral data with reference standards, four characteristic peaks in the chromatograms were confirmed as corresponding to acetoside, angoroside C, cinnamic acid, and harpagoside. In addition, other two characteristic peaks were tentatively identified, following the literature interpretation of HPLC-ESI-MS and LC-MS/MS (affording structural information) to be sibirioside A and scrophuloside B(4), respectively. The results indicated that the newly developed HPLC-DAD-MS fingerprint method would be suitable for quality control of Radix Scrophulariae.

Simultaneous Determination of Eight Anthraquinones in Semen Cassiae by HPLC-DAD

INTRODUCTION Semen Cassiae (SC), a traditional Chinese herbal medicine for the treatment of various diseases, is known to contain active anthraquinone ingredients. However, since the content of some anthraquinones is too low, previous analytical methods only allow the quantitation of a few anthraquinones or a hydrolysis step has to be included in the sample preparation. A rapid and accurate method to examine the content of as many anthraquinones as possible in SC would be desirable. OBJECTIVE To develop a rapid, sensitive and accurate high-performance liquid chromatography-diode array detection (HPLC- DAD) method to simultaneously quantify eight major anthraquinones (obtusifolin-2-glucoside, aurantio-obtusin, aloe- emodin, rhein, obtusifolin, emodin, chrysophanol and physcion) in SC. METHODOLOGY The separation of anthraquinones was achieved on a C₁₈-column with a gradient elution using acetonitrile and 0.1% phosphoric acid. The detection wavelength was 278 nm and the analysis finished within 25 min. RESULTS The limits of detection of these compounds ranged from 0.07 to 0.15 µg/mL while the limits of quantitation ranged from 0.24 to 0.51 µg/mL. All calibration curves showed good linearities (r²  > 0.999) within the test ranges. This validated method was successfully used to analyse 22 batches of SC samples collected from various geographical locations. CONCLUSION The method was validated to be simple, rapid, accurate and reliable to simultaneously determine eight major anthraquinones in SC. Meanwhile, a more specific anthraquinone, obtusifolin, was proposed to serve as a marker for SC, replacing chrysophanol.

Anti-inflammatory activities and mechanisms of action of the petroleum ether fraction of Rosa multiflora Thunb. hips.

ETHNOPHARMACOLOGICAL RELEVANCE The hip of Rosa multiflora Thunb. has been traditionally used as a dietary supplement and a herbal remedy for the treatment of various diseases including cold, flu, inflammation, osteoarthritis, rheumatoid arthritis and chronic pain in China. AIMS OF THE STUDY To explore the anti-inflammatory ingredient of the hip of R. multiflora Thunb. and its mechanism of action. MATERIALS AND METHODS The ethanol extract of the hip of R. multiflora Thunb. was fractioned with petroleum ether, ethyl acetate and water, and each fraction was screened for anti-inflammatory activity in xylene-induced mouse ear edema model. Three more models, acetic acid-induced mouse vascular permeation, cotton pellet-induced rat granuloma, and carrageenan-induced rat hind paw edema were also employed to verify the anti-inflammatory effect of the identified fraction. To explore the mechanism of action, the activity of inducible nitric oxide synthase (iNOS) and the level of nitric oxide (NO) in sera, as well as mRNA expression level of cyclo-oxygenase-2 (COX-2) in inflammatory tissues of rats with carrageenan-induced hind paw edema were measured. GC-MS technology was applied to identify the active components in the active fraction. RESULTS AND CONCLUSIONS The petroleum ether fraction (PEF) was identified to be the active fraction in inflammation animal models (i.e., oral administration of PEF (168.48, 42.12 and 10.53 mg/kg) evoked a significantly (P<0.001) dose-dependent inhibition of the xylene-induced mice ear edema). Down-regulating COX-2 expression (P<0.001) and reducing NO production (P<0.05) through inhibiting iNOS activity (P<0.001) may be the partial mechanism of action of PEF. GC-MS analysis indicated that unsaturated fatty acids are enriched in PEF and may be responsible for the anti-inflammatory activity of PEF and this herb. The results of this study provide pharmacological and chemical basis for the application of the hip of R. multiflora Thunb. in inflammatory disorders.

Petroleum ether extractive of the hips of Rosa multiflora ameliorates collagen-induced arthritis in rats

ETHNOPHARMACOLOGICAL RELEVANCE The hip of Rosa multiflora Thunb. (HRM) has been traditionally used as a dietary supplement and a herbal remedy for the treatment of various diseases, including inflammation, osteoarthritis, rheumatoid arthritis and chronic pain, in China. The current study was to evaluate the therapeutic efficacy of the petroleum ether extractive of HRM (PEE) on type II collagen-induced rheumatoid arthritis (CIA) in male Wistar rats. In addition, the anti-inflammatory mechanism(s) of PEE on type II CIA was explored. MATERIALS AND METHODS Rheumatoid arthritis (RA) was induced by intradermal injection of bovine type II collagen on Day 1 and Day 8. Starting from Day 13, normal rats were treated with vehicle (serving as the control group); the CIA rats were treated with vehicle (CIA group), dexamethasone (0.25mg/kg bw per day, p.o.) (a positive control), lei-gong-teng (LGT: 10mg/kg bw per day, p.o.) (a clinically used Chinese patent medicine in RA therapy) or PEE (12, 36 or 120mg/kg bw per day, p.o.) for 28 days. RESULTS AND CONCLUSIONS PEE (120mg/kg bw per day) efficiently attenuated the severity of arthritis in the CIA rats by reducing the mean arthritis severity scores and the fore/hind paw swelling as well as reduced histological changes by decreasing the cartilage surface erosion and cartilage proteoglan depletion. PEE׳s therapeutic effect in RA may involve the inhibition of pro-inflammatory cytokines, such as TNF-α, IL-1β and IL-6, in serum and/or the elevation of the activities of hepatic anti-oxidative enzymes including SOD, CAT and GSH-Px. However, the detailed anti-inflammatory mechanism, the main effective components and the interaction between different ingredients in PEE are still not clear and require more studies.

A Review of the Phytochemistry and Pharmacological Activities of Raphani Semen

The dried ripe seed of Raphanus sativus L., commonly known as radish seed (or Raphani Semen), is used as traditional Chinese medicine (TCM) to treat constipation, chronic tracheitis, and hypertension. The major active compounds in Raphani Semen are alkaloids, glucosinolates, brassinosteroids, and flavonoids. Fatty acids are its main nutritional contents. Raphani Semen has been demonstrated to have beneficial effects on hypertension, obesity, diabetes mellitus, constipation, and cough. So far, there is no report about the adverse/toxic effects of this herb on humans. However, Raphani Semen processed by roasting was reported to exhibit some adverse effects on mice. Additionally, erucic acid, the main fatty acid in Raphani Semen, was shown to enhance the toxicity of doxorubicin. Thus, Raphani Semen has a potential risk of causing toxicity and drug interaction. In summary, Raphani Semen is a valuable TCM herb with multiple pharmacological effects. More studies on Raphani Semen could help better understand its pharmacological mechanisms so as to provide clear scientific evidence to explain its traditional uses, to identify its therapeutic potential on other diseases, and to understand its possible harmful effects.

Rapid authentication of Gastrodiae rhizoma by direct ionization mass spectrometry

In this study, direct ionization mass spectrometry (DI-MS) for rapid authentication of Gastrodiae rhizoma (known as Tianma in Chinese), a popular herbal medicine, has been developed. This method is rapid, simple and allows direct generation of characteristic mass spectra from the raw herbal medicines with the application of some solvents and a high voltage. The acquired DI-MS spectra showed that gastrodin, parishin B/parishin C and parishin, the major active components of Gastrodiae rhizoma, could be found only in genuine Gastrodiae rhizoma samples, but not in counterfeit samples, thus allowing rapid authentication of Gastrodiae rhizoma. Moreover, wild and cultivated Gastrodiae rhizoma could be classified and Gastrodiae rhizoma from different geographical locations could be differentiated based on their different intensity ratios of characteristic ions or principal component analysis (PCA). This method is simple, rapid, reproducible, and can be extended to analyze other herbal medicines.