Zhitao Liang

Macroscopic identification of Chinese medicinal materials: traditional experiences and modern understanding.

Authentication is fundamental for the standardization of Chinese Materia Medica. Macroscopic identification, an important method of authentication, has a long history rooted in practice and experience over generations. In ancient times, macroscopic features were used not only to identify the genuineness, but also to evaluate the quality of Chinese medicinal materials (CMMs). In many ancient documents, picturesque terms were used to describe the quality of certain specific CMMs. These traditional macroscopic descriptions used for identification are filled with characteristics, quality descriptions, and specifications of CMM that need to be confirmed by modern scientific analysis. In this paper, the essential and fundamental components of macroscopic identification are introduced. As the quality and macroscopic characteristics of CMM are traditionally thought to be closely related, modern scientific approaches to confirm the validity of these associations are discussed. This review clarifies the role of macroscopic features in the quality assessment of CMM.

Comparison of raw and processed Radix Polygoni Multiflori (Heshouwu) by high performance liquid chromatography and mass spectrometry.

BackgroundRadix Polygoni Multiflori is the dried root tuber of Polygonum multiflorum Thunb. (Fam. Polygonaceae). According to Chinese medicine theory, raw (R-RPM) and processed (P-RPM) Radix Polygoni Multiflori possess different properties. The present study investigates the differences in chemistry between raw and processed Radix Polygoni Multiflori.MethodsFive pairs of R-RPM and P-RPM as well as 15 commercial decoction pieces were analyzed with high performance liquid chromatography (HPLC) and mass spectrometry (MS).ResultsTwo anthraquinones, namely emodin-8-O-(6-O-malonyl)-glucoside and physcion-8-O-(6-O-malonyl)-glucoside disappeared or decreased significantly and 2,3,5,4-tetrahydroxystilbene-2-O-β-D-glucopyranoside, emodin-8-O-β-D-glucopyranoside and physcion-8-O-β-D-glucopyranoside decreased after the R-RPM samples being processed. On the other hand, the contents of emodin and physcion generally increased after processing.ConclusionThe present study indicates that processing Radix Polygoni Multiflori may change the contents and types of chemicals in it. These changes are probably responsible for the various pharmacological effects of R-RPM and P-RPM as well as hepatotoxicity.

Rapid screening method for intact glucosinolates in Chinese medicinal herbs by using liquid chromatography coupled with electrospray ionization ion trap mass spectrometry in negative ion mode.

An optimized method using liquid chromatography coupled with electrospray ionization ion trap mass spectrometry (LC/ESI-ITMS) in negative ion mode has been developed for screening different structural classes of intact glucosinolates in six Chinese medicinal herbs. The glucosinolates were extracted with hot methanol/water (70:30 v/v) and separation of the individual glucosinolates was achieved using a reversed-phase C18 column with an aqueous ammonium acetate/methanol gradient. Identification of the intact glucosinolates was based on the detection of compounds with a constant neutral loss of 242 Da corresponding to the combined loss of anhydroglucose (162 Da) and sulfur trioxide (80 Da) in collision-induced dissociation. The structures of the identified glucosinolates were confirmed with the use of group-specific product ions at m/z 195, 241, 259, 275 in their corresponding MS/MS product ion spectra. Differentiation of intact glucosinolates was achieved through their respective retention times and molecular masses as well as the characteristic product ions. The limits of detection were at the low nanogram level per injection, based on constant neutral loss scans. Significant variation in the compositions of intact glucosinolates was identified in the cruciferous herbs. This method was applied in the differentiation and quality control of two pairs of easily confused herbs.

An experimental study on four kinds of Chinese herbal medicines containing alkaloids using fluorescence microscope and microspectrometer.

In order to find a useful method for uniting the identification and quality evaluation of Chinese herbal medicine, the techniques of fluorescence microscopy and microspectrometer were firstly applied to authenticate four kinds of herbal medicines, Caulis Sinomenii, Rhizoma Coptidis, Radix Sophorae Tonkinensis and Rhizoma Menispermi, as well as to measure the distribution of alkaloids in their cross‐sections. The results showed that the fluorescence microscopic characteristics and the fluorescence emission spectra of the same tissues from the four kinds of Chinese herbal medicine were different, for example, the cortex of Radix Sophorae Tonkinensis emitted blue fluorescence instead of the yellow of Rhizoma Coptidis observed with emission filter of long‐pass 397 nm, which could be effective to identify them. Furthermore, alkaloids, as active components of the above herbal medicines, were distributed in each part of herbal tissue but their fluorescence intensities in different parts of tissue were different. The results indicated that fluorescence microscope combined with microspectrometer could be a helpful method for identification and quality evaluation of Chinese herbal medicine.

Whole transverse section and specific-tissue analysis of secondary metabolites in seven different grades of root of Paeonia lactiflora using laser microdissection and liquid chromatography-quadrupole/time of flight-mass spectrometry.

The root of Paeonia lactiflora Pall. is widely used in the pharmaceutical, food and cosmetic industries. For these purposes, roots are graded according to diameter, with larger roots considered to be of better quality. To assess the inherent quality of different grades and of different tissues in roots of P. lactiflora, here laser microdissection coupled with UPLC-Q/TOF-MS was applied. The results show the quantity of pharmaceutically important components decreased with increase in root diameter from 0.3cm to 0.7cm. Above 0.7cm of diameter, quantity and diversity of these components increased proportionally with increase in root diameter. The tissue-specific study indicated that the high content of paeoniflorin and albiflorin are mainly distributed in the cork and cortex. According to the results of this study, the roots of P. lactiflora greater than 1.7cm in diameter are of better quality medicinal use than smaller, and the commercial grades chose was best cutoff points. The fine roots and the outer bank of roots, which besides the commercial grades, contain such significant amounts of chemical components too. This study provides a new and practical method for evaluating the different grades of P. lactiflora.

Histochemical evaluation of alkaloids in rhizome of Coptis chinensis using laser microdissection and liquid chromatography/mass spectrometry

Traditional macroscopic and microscopic identification methods of medicinal materials are economical and practical, but usually experience-based due to few chemical supports. Here histochemical evaluation on bioactive components of Coptidis Rhizoma (CR) in anatomic sections using laser microdissection and liquid chromatography-mass spectrometry (LMD-LC-MS) was developed to correlate the inner quality and outer features of materials from different growing areas. Results of a total 33 peaks representing potential different alkaloids were detected and 8 common peaks were identified as the major alkaloids, namely magnoflorine, thalifendine, columbamine, epiberberine, jatrorrhizine, coptisine, palmatine, and berberine. Six major alkaloids were quantified in the top and middle sections of raw materials and in their tissues and cells at the same time. Histochemical analyses showed consistent results with direct determination in raw materials and explained the reason why top sections of all samples contained higher contents of alkaloids by giving out attributions of each alkaloid in different anatomic sections. Besides, results manifested the distribution and accumulation rules of alkaloids in diverse tissues and cells of CR. This study demonstrates an effective and scientific way to correlate bioactive components and morphological features of medicinal materials, which is beneficial to future research, agriculture and application.

Fingerprint analysis of processed Rhizoma Chuanxiong by high-performance liquid chromatography coupled with diode array detection

BackgroundRhizoma Chuanxiong (RC) is the dried rhizome of Ligusticum chuanxiong Hort., and various types of processed Rhizoma Chuanxiong (PRC) are widely used in China. However, quality assurance and quality control of these processed medicines remain challenging. This study aims to investigate the chemical compositions of various PRC preparations by a high-performance liquid chromatography (HPLC) coupled with diode array detection (DAD) method.MethodsA HPLC-DAD method with validation was developed for PRC samples. Seven batches of plant samples from two processing methods, stir-frying and steaming, were analyzed by the HPLC-DAD method. Common peaks in PRC chromatograms were chosen to calculate their relative retention time (RRT) and relative peak area (RPA), and similarity analyses of the chromatographic fingerprints were conducted by Similarity Evaluation System for Chromatographic Fingerprint of Traditional Chinese Medicine software (Version 2004 A).ResultsIn the 24-h stability test, the relative standard deviation for the RRT and RPA was less than 0.07% and 2.57%, respectively. The precision was less than 0.08% for the RRT and 2.48% for the RPA. The repeatability for the RRT and RPA was less than 0.03% and 2.64%, respectively. The similarities between the seven PRC batches were range from 0.956 to 0.990. After stir-frying or steaming, the amount of ferulic acid in PRC was much higher than that in the raw material.ConclusionsThe fingerprint analysis of PRC by different processing methods was feasible by HPLC-DAD.

Characterization of shapes for use in classification of starch grains images.

As tradition Chinese herbal medicine becomes increasingly popular, there is an urgent need for efficient and accurate methods for the authentication of the Chinese Materia Medica (CMM) used in the herbal medicine. In this work, we present a denoising filter and introduce the use of chord length distribution (CLD) for the classification of starch grains in microscopic images of Chinese Materia Medica. Our simple denoising filter is adaptive to the background and is shown to be effective to remove noise, which appears in CMM microscopic starch grains images. The CLD is extracted by considering the frequency of the chord length in the binarized starch grains image, and we shall show that the CLD is an efficient and effective characterization of the starch grains. Experimental results on 240 starch grains images of 24 classes show that our method outperforms benchmark result using the current state‐of‐the‐art method based on circular size distribution extracted by morphological operators at much higher computational cost. cost. Microsc. Res. Tech., 2008.

Rabdosia japonica var. glaucocalyx Flavonoids Fraction Attenuates Lipopolysaccharide-Induced Acute Lung Injury in Mice

Rabdosia japonica var. glaucocalyx (Maxim.) Hara, belonging to the Labiatae family, is widely used as an anti-inflammatory and antitumor drug for the treatment of different inflammations and cancers. Aim of the Study. To investigate therapeutic effects and possible mechanism of the flavonoids fraction of Rabdosia japonica var. glaucocalyx (Maxim.) Hara (RJFs) in acute lung injury (ALI) mice induced by lipopolysaccharide (LPS). Materials and Methods. Mice were orally administrated with RJFs (6.4, 12.8, and 25.6u2009mg/kg) per day for 7 days, consecutively, before LPS challenge. Lung specimens and the bronchoalveolar lavage fluid (BALF) were isolated for histopathological examinations and biochemical analysis. The level of complement 3 (C3) in serum was quantified by a sandwich ELISA kit. Results. RJFs significantly attenuated LPS-induced ALI via reducing productions of the level of inflammatory mediators (TNF-α, IL-6, and IL-1β), and significantly reduced complement deposition with decreasing the level of C3 in serum, which was exhibited together with the lowered myeloperoxidase (MPO) activity and nitric oxide (NO) and protein concentration in BALF. Conclusions. RJFs significantly attenuate LPS-induced ALI via reducing productions of proinflammatory mediators, decreasing the level of complement, and reducing radicals.

Identification of Chinese herbal medicines by fluorescence microscopy: fluorescent characteristics of medicinal bark

Medicinal bark refers to structures outside the vascular cambium of stems, branches and roots of gymnospermous and dicotyledonous plants that are used as medicinal materials; bark is an important type of Chinese herbal medicine. However, identification of the species from which the bark comes can be very difficult, especially when the bark is dried and sliced. In our previous studies, we have found that fluorescence microscopy is a powerful tool for the identification of easily confused Chinese herbal medicines, powdered Chinese herbal medicines and decoction dregs. To establish the fluorescent characteristics by which medicinal barks can be identified, for ensuring their safe and effective use, a systematic microscopic investigation by normal light and fluorescence microscope was carried out on transverse section samples of 11 medicinal barks commonly used in China. Specifically, the fluorescent characteristics of mechanical tissues, including stone cells and fibres as well as secretory tissues, have been observed. The microscopic features of medicinal bark are here systematically and comparatively described and illustrated. Under the fluorescence microscope, various tissues emitted fluorescence of different colours, and we found that both the colours and the intensity can be used to distinguish and identify these barks.