Journal of Chromatography B (v.812, #1-2)

Preface by Z. Deyl (1).

Chinese herbal medicine is gaining increasing popularity worldwide for health promotion and adjuvant therapy. Thus, selective and efficient analytical methods are required not only for quality assurance but also for authentication of the plant material. Applications of both chromatographic and electrophoretic techniques to the analysis of medicinal plants and Chinese traditional medicine preparations over the last 3 years are outlined in this review. The role of chemical fingerprinting is highlighted and a brief survey of determination of toxic components, natural and synthetic adulterants is also included. Moreover, different sample pretreatment and extraction methods are discussed.
Keywords: Analysis; Chromatography; Separation; Fingerprint; TCM; Chinese medicine; Drugs; Preparations;

Botanicals and herbal preparations are medicinal preparations, containing a single or two or more medicinal plants. The focus of this review paper is on the analytical methodologies, which included the combination of sample preparation tools and chromatographic techniques for the chemical standardization of marker compounds or active ingredients in botanicals and herbal preparations. The common problems and key challenges in the chemical standardization of botanicals and herbal preparations were discussed. As sample preparation is the most important step in the development of analytical methods for the analysis of constituents present in botanicals and herbal preparations, the strength and weakness of different extraction techniques are discussed. For the analysis of compounds present in the plant extracts, the applications of common chromatographic techniques, such as HPLC, CE, HRGC/MS, HPLC/MS and HPLC/MS/MS are discussed. The strength, weakness and applicability of various separation tools are stated. Procedures for the identification of marker or active compounds in plant extracts, using HPLC/MS, were proposed. Finally, the effects of batch-to-batch variation of the medicinal plants are investigated and discussed.
Keywords: Sample preparation; Extraction; Botanicals; Herbal preparations;

The paper summarizes the state of art of different separation methods which are used for the analysis and isolation of plant constituents. An overview about the extraction methods which are frequently used for the non-volatile constituents of plants is given. Special attention is paid to the identification possibilities of non-volatile and volatile compounds, since generally the role of identification of plant's constituents is undervalued. We would emphasize the facts that, for correct identification, the various chromatographic and spectroscopic methods have to be used in conjunction. The application of two different methods from each field is usually sufficient. For quantitative information, two independent methods are necessary and are acceptable if the results are within 3% of each other. If only one method is available for quantitative analysis, the results can only be accepted if, using the global optimum, the ratios of the components determined are identical to one decimal place with the ratios of three measurements (local optima) using different mobile phases with different selectivities. Based on our own 20-year experience and more than a hundred isolated compounds, we give an isolation strategy where the structures and properties of the compounds to be isolated do not have to be known. It is pointed out that without analytical monitoring, the results of preparative separations cannot be guaranteed.
Keywords: Reviews; Extraction; Purification; Phytoanalysis; Medicinal plants; Secondary constituents; Bioactivity;

Quality control of herbal medicines by Yi-Zeng Liang; Peishan Xie; Kelvin Chan (53-70).
Different chromatographic and electrophoretic techniques commonly used in the instrumental inspection of herbal medicines (HM) are first comprehensively reviewed. Chemical fingerprints obtained by chromatographic and electrophoretic techniques, especially by hyphenated chromatographies, are strongly recommended for the purpose of quality control of herbal medicines, since they might represent appropriately the “chemical integrities” of the herbal medicines and therefore be used for authentication and identification of the herbal products. Based on the conception of phytoequivalence, the chromatographic fingerprints of herbal medicines could be utilized for addressing the problem of quality control of herbal medicines. Several novel chemometric methods for evaluating the fingerprints of herbal products, such as the method based on information theory, similarity estimation, chemical pattern recognition, spectral correlative chromatogram (SCC), multivariate resolution, etc. are discussed in detail with examples, which showed that the combination of chromatographic fingerprints of herbal medicines and the chemometric evaluation might be a powerful tool for quality control of herbal products.
Keywords: Herbal medicines; Fingerprints; Quality control; Chemometrics;

Strategy for analysis and screening of bioactive compounds in traditional Chinese medicines by Xiaodong Huang; Liang Kong; Xin Li; Xueguo Chen; Ming Guo; Hanfa Zou (71-84).
Traditional Chinese medicines (TCMs), due to their long time clinic test and reliable therapeutic efficacy, are attracting increased global attention served as excellent pools of bioactive compounds for the discovery of new drugs. However, hundreds or even thousands of components are usually contained in traditional Chinese medicines and only a few compounds are responsible for the pharmaceutical and/or toxic effects. The large numbers of other components in traditional Chinese medicines make the screening and analysis of the bioactive components extremely difficult. By the way, the combination effect of bioactive components on the pharmacological activity makes it very difficult to clear the therapeutic mechanism of TCMs. Therefore, some strategies have to design for screening of bioactive compounds in traditional Chinese medicines, which further leads to disclose the therapeutic mechanism of TCMs in molecular level. The review will summarize the present state of the art of screening strategy for active compounds in traditional Chinese medicines, and the chromatography methods for screening and analysis of bioactive compounds in traditional Chinese medicines will be emphasized.
Keywords: Reviews; Screening; Bioactive compounds;

Phytochemicals in fruits, vegetables, spices and traditional herbal medicinal plants have been found to play protective roles against many human chronic diseases including cancer and cardiovascular diseases (CVD). These diseases are associated with oxidative stresses caused by excess free radicals and other reactive oxygen species. Antioxidant phytochemicals exert their effect by neutralizing these highly reactive radicals. Among the tens of thousands of phytochemicals found in our diets or traditional medicines, polyphenols and carotenoids stand out as the two most important groups of natural antioxidants. However, although collectively these phytochemicals are good antioxidants, the roles and effect of individual compounds are often not well known. Hundreds of carotenoids and thousands of polyphenols have been identified so far from various plants. A single plant could contain highly complex profiles of these compounds, which sometimes are labile to heat, air and light, and they may exist at very low concentrations in the plants. This makes the separation and detection of these antioxidant phytochemicals a challenging task. The present review focuses on the antioxidant activity, chemical types, sampling and sample processing procedures, and separation using various chromatographic and electrophoretic techniques. Detection and quantification using ultraviolet–visible–diode array and mass spectrometry will be discussed.
Keywords: Review; Antioxidant phytochemicals; Separation; Phytochemicals; Antioxidants; Carotenoids; Polyphenols; Flavonoids; HPLC; HSCCC; LC–MS; SFE; SFC;

Separation methods for antibacterial and antirheumatism agents in plant medicines by Dawei Wen; Yuping Liu; Wei Li; Huwei Liu (101-117).
Traditional oriental medicines (TOM), with a very long history and many remarkable features, are very popular in Asian countries, especially in China, Japan and Korea. With the development of advanced analytical techniques, the modernization of traditional medicine has become a hot area in recent years and some herbal medicines have been increasingly accepted in western countries. Separation and determination of active components in various herbal medicines are considered to be critical for the modernization process. Antibacterial and antirheumatism agents are widely distributed in many medical plants and commonly used in clinical treatment. Therefore, the development of effective separation methods for the quality control of herbal medicines is absolutely important. In this article, the separation methods for the analysis of antibacterial and antirheumatism compounds in TOM were reviewed, including thin layer chromatography (TLC), gas chromatography (GC), supercritical fluid chromatography (SFC), high-performance liquid chromatography (HPLC), capillary electrophoresis (CE) and related hyphenation techniques. Sample preparation procedures and further development of these methods were also discussed.
Keywords: Reviews; Antibacterial compounds; Antirheumatism compounds;

Analysis methods of ginsenosides by Nicola Fuzzati (119-133).
Ginsenosides are considered the main active principles of the famous Chinese traditional medicine “ginseng”. For more than 30 years many researchers developed methods for the identification and quantification of ginsenosides in ginseng plant material, extracts and products. Separation of ginsenosides has been achieved using thin layer chromatography (TLC), gas chromatography (GC) and high performance liquid chromatography (HPLC). Among these techniques HPLC is by far the most employed. Ultraviolet (UV), evaporative light scattering (ELSD), fluorescence and, recently, mass spectrometry (MS) were coupled with HPLC for the detection of ginsenosides. The most recent methods are here discussed together with a critical evaluation of the published results. Furthermore new techniques such as near infrared spectroscopy (NIRS) and enzyme immunosassay (EIA) recently used for the determination of ginsenosides will be discussed.
Keywords: Ginsenosides;

Separation and isolation methods for analysis of the active principles of Sho-saiko-to (SST) oriental medicine by Nobuhiro Ohtake; Yoichiro Nakai; Masahiro Yamamoto; Iwao Sakakibara; Shuichi Takeda; Sakae Amagaya; Masaki Aburada (135-148).
Sho-saiko-to (SST) was introduced into Japan as an oriental classical medicine from China approximately 1500 years ago, and it is currently the most representative Kampo medicine (traditional Japanese medicine). SST is manufactured in Japan as an ethical drug on a modern industrial scale in which the quality of ingredients is standardized with Good Manufacturing Practices (GMP) regulation. SST is widely used for the treatment of chronic hepatitis. Experimental and clinical studies including multi-center, placebo-controlled, double-blind studies have demonstrated the various pharmacological effects of SST. SST is prepared from the hot water extraction of seven raw materials, therefore many kinds of constituents are included. Three-dimensional (3D) HPLC analysis is useful for obtaining many kinds of constituents, especially low molecular ultraviolet (UV) quenching compounds, contained in SST as well as its fractions. Fingerprint pattern provided by 3D HPLC analysis makes possible to identify the overall-viewing of SST. Databases of UV spectra of the components of medicinal herbs obtained by reversed-phase (RP) HPLC using a photodiode array (PDA) and fingerprint patterns of crude drugs made by 3D HPLC analysis facilitate the identification, analysis and quality of herbal drugs. Studies using both PDA HPLC and an amino acid analysis with a fluorometric detector have found that SST contains fifteen major low molecular compounds (i.e. baicalin, wogonin-7-O-glucuronide, liquiritin, their three aglycons, liquiritin apioside, glycyrrhizin, saikosaponin b1, saikosaponin b2, ginsenoside Rg1, ginsenoside Rb1, (6)-gingerol, (6)-shogaol and arginine). These compounds have various pharmacological actions, and are assumed to be responsible, at least partly, for the pharmacological effects of SST. Although there have only been a few investigations on high molecular compounds with pharmacological actions contained in SST, several kinds of polysaccharides have been isolated from constituent herbs of SST. This review paper summarizes analytical methods of separation, isolation and identification of compounds with biological activities from SST, which is a mixture drug of medicinal herbs. Accordingly, this paper would not focus on methods of separation, isolation and analysis of particular compounds from each constituent herb of SST.
Keywords: Reviews; Fingerprinting; Sho-saiko-to medicine;

Liquid chromatography of active principles in Sophora flavescens root by Xi Chen; Changqing Yi; Xiaoqing Yang; Xiaoru Wang (149-163).
Herbal medicines were one of the major resources for healthcare in earlier stages, and some traditional herbal medicines have been in use for more than 2000 years. Currently, they are attracting more and more attention of the modern pharmaceutical industry, as scientists has become aware that herbs have almost infinite resources for medicine development. This review provides an overview of the analytical approaches applied in the researches concentrated on various aspects of the matrine-type alkaloids in Sophora flavescens root. Emphasis will be laid on the analytical processes of high-performance liquid chromatography (HPLC), capillary electrophoresis (CE), as well as gas chromatography (GC) methods. The sample extraction, separation and detection have been summarized. In addition, the applications of chromatographic determinations are introduced for the main matrine-type alkaloids in S. flavescens root, such as matrine, sophoridine, sophocarpine, lehmannine, sophoramine, oxymartine, oxysophocarpine, cytosine and aloperine. The advantages and limitations of HPLC, CE and GC methods in the analytical applications of the alkaloids are also discussed.
Keywords: Matrine-type alkaloids; Sophora flavescens root; Chinese medicines;

Xanthones, as a kind of polyphenolic natural products with many strong bioactivities, are attractive for separation scientists due to the similarity and diversity of their structures resulting in difficult separation by chromatographic methods. High performance liquid chromatography (HPLC) and thin layer chromatography (TLC) are traditional methods to separate xanthones. Recently, capillary electrophoresis (CE), as a micro-column technique driven by electroosmotic flow (EOF), with its high efficiency and high-speed separation, has been employed to separate xanthones and determine their physicochemical properties such as binding constants with cyclodextrin (CD) and ionization constants. Since xanthones have been used in clinic treatment, the development of chromatographic and CE methods for the separation and determination of xanthones plays an essential role in the quality control of some herbal medicines containing xanthones. This article reviewed the separation of xanthones by HPLC, TLC and CE, citing 72 literatures. This review focused on the CE separation for xanthones due to its unique advantages compared to chromatographic methods. The comparison of separation selectivity of different CE modes including capillary zone electrophoresis (CZE), micellar electrokinetic chromatography (MEKC), microemulsion electrokinetic capillary chromatography (MEEKC) and capillary electrochromatography (CEC) was discussed. Compared with traditional chromatographic methods such as HPLC and TLC, CE has higher separation efficiency, faster separation, lower cost and more flexible modes. However, because of low sensitivity of UV detector and low contents of xanthones in herbal medicines, CE methods have seldom been applied to the analysis of real samples although CE showed great potential for xanthone separation. The determination of xanthones in herbal medicines has been often achieved by HPLC. Hence, how to enhance CE detection sensitivity for real sample analysis, e.g. by on-line preconcentration and CE-MS, would be a key to achieve the quantitation of xanthones.
Keywords: Review; Xanthones; Herbal medicines;

Rhubarb, as an important Chinese medicine, has many functions owing to containing anthraquinone derivatives. The analysis of anthraquinone derivatives in Chinese rhubarb is reviewed. The analytical techniques include high performance liquid chromatography, capillary electrophoresis, thin-layer chromatography and so on. The main operation parameters in every technique were given. The structures of anthraquinone derivatives and the classification of Chinese rhubarb were summarized too.
Keywords: Review; Rhubarb; Anthraquinones; Perivatization;

Biologically active components of Physostigma venenosum by Bin Zhao; Shabbir M. Moochhala; Su-yin Tham (183-192).
Physostigmine is a major alkaloid found in the seeds of the fabaceous plant Physostigma venenosum. It is a powerful and reversible acetylcholine esterase inhibitor which effectively increases the concentration of acetylcholine at the sites of cholinergic transmission. It exerts its cholinesterase inhibitor effect in both the periphery and central nervous system. Many studies on physostigmine have involved the reliance on techniques that extract and quantify physostigmine in biological samples. This paper presents an overview of the currently applied methodologies for the determination of physostigmine and its metabolites in various biological samples. Papers published from January 1980 to December 2003 were taken into consideration for the discussion of the metabolism and analytical method of physostigmine. HPLC methods have been discussed and used in most of the references cited in this review. A few CE and RIA methods that have been recently reported are also mentioned in this paper. Basic information about the sample assayed, sample preparation, chromatographic column, mobile phase, detection mode and validation data are summarized in a table.
Keywords: Physostigma venenosum;

Gardenia herbal active constituents: applicable separation procedures by Shau-Chun Wang; Ting-Yu Tseng; Chih-Min Huang; Tung-Hu Tsai (193-202).
Gardenia herb has been used as alternative drug for thousand years. They may provide therapeutic or cause toxic effect. Recently, large scale of biological screen, phytochemical separation, isolation, and identification were widely performed. Quality control of the active ingredients should be concern for the application of Gardenia herbs. Many systems have been developed for the determination of herbal ingredients. This article reviews some of the plants and their active constituents that have been used for medicinal applications. The sample preparation, separation, and determination of Gardenia herbal ingredients were discussed. Based on the separation, the method of gas chromatography, liquid chromatography, and capillary electrophoresis were also discussed.
Keywords: Gardenia herbal ingredients; Traditional Chinese medicines;

Analysis of kavalactones from Piper methysticum (kava-kava) by Anna Rita Bilia; Luca Scalise; Maria Camilla Bergonzi; Franco F. Vincieri (203-214).
The chemical analysis and quality control of both Piper methysticum G. Forster (kava-kava) and extracts obtained by aqueous acetone or aqueous methanol as well as supercritical fluid extraction are reviewed. In the last two decades various procedures concerning the separation and detection of kavalactones have been routinely carried out by gas chromatography (without previous derivatization of kavalactones) and high performance liquid chromatography but most of them are not validated or only partially validated. Recently, analyses by supercritical fluid chromatography and micellar electrokinetic chromatography have also been reported. Both gas chromatography and high performance liquid chromatography can be used for the analysis of kavalactones with some advantages and disadvantages for each method. Using gas chromatography analysis, methysticin and yangonin, which are two of the major components, are generally not separated. In addition, the high temperature of the injection port caused the decomposition of methysticin. Concerning high performance liquid chromatography analyses, the reversed-phase is generally better because highly reproducible with a very low detection limit for all compounds even if the quantitative analysis of the kavalactones by liquid chromatography needs to be carried out in the absence of light to prevent the cis/trans isomerisation of yangonin.
Keywords: Piper methysticum G. Forster; Kavalactones;

Separation procedures applicable to lignan analysis by Jiří Slanina; Zdeněk Glatz (215-229).
Lignans are a class of secondary plant metabolites produced by oxidative dimerization of two phenylpropanoid units. They have been found in many plants of Oriental medicine. In consequence of recent knowledge it is held that lignans are responsible for the key pharmacological activities of these plants. This review surveys the chromatographic, electromigration and hyphenated methods so far applied for the separation of lignans in Oriental plants used in phytotherapy as well as for the analyses of these lignans and their metabolites in biological matrices and food samples. In addition, the sample clean-up procedures—solvent extractions and supercritical fluid extractions—are also included.
Keywords: Reviews; Lignans;

In this review, chemical constituents present in Rhododendron dauricum L. were briefly surveyed, and the methods of pretreatment of this plant prior to analysis were also summarized. The analysis methods reported for determining pharmaceutically active compounds in R. dauricum L. include gas chromatography with mass spectrscopy, thin layer chromatography (TLC), high performance liquid chromatography (HPLC) and capillary electrophoresis (CE). In addition, both advantages and disadvantages of the above methods were mentioned.
Keywords: Reviews; Rhododendron dauricum;

Lingzhi is the Chinese name given to the Ganoderma family of mushrooms, which was considered the most valuable medicine in ancient China and was believed to bring longevity, due to its mysterious power of healing the body and calming the mind. Today, Lingzhi is still widely revered as a valuable health supplement and herbal medicine worldwide, as studies (mostly conducted in China, Korea, Japan and the United States) into the medicinal and nutritional values of Lingzhi revealed that it does indeed contain certain bioactive ingredients (such as triterpenes and polysaccharides) that might be beneficial for the prevention and treatment of a variety of ailments, including important diseases such as hypertension, diabetes, hepatitis, cancers, and AIDS. As research into the biological activities of Lingzhi, as well as the quality assurance and quality control of Lingzhi products, require the isolation/purification of active ingredients from Lingzhi, followed by subsequent analytical and/or preparative separations, the present review summarizes the various chromatographic and electrophoretic methods (as well as sample pretreatment methods) typically employed to achieve such extraction/separation procedures.
Keywords: Lingzhi; Chromatographic/electrophoretic methods; Active ingredients; Triterpenes/triterpenoids; Polysaccharides;

Separation methods of quinonoid constituents of plants used in Oriental traditional medicines by Banasri Hazra; Madhushree Das Sarma; Utpal Sanyal (259-275).
Analysis of molecular constituents of traditional Oriental medicines has acquired a fresh perspective in view of a surge in interest in the consumption of herbal prescriptions all over the world. Several of them contain quinonoid compounds, and the long-standing therapeutic applications of these herbs have been vindicated, to some extent, through recent studies on the significant pharmacological properties of these compounds. In fact, the bioactive quinonoids and their analogues often serve as the ‘marker’ constituents of the respective plants of major commercial importance. Hence, shikonin, plumbagin, diospyrin, emodin analogues, sennosides, hypericin, tanshinone and related compounds have been discussed in this review which focuses on their extraction, separation and analysis from plant sources, cell cultures and biological fluids. As for the analysis of quinonoids, high-performance liquid chromatography connected with various detectors (ultraviolet, photodiode array, fluorescence, mass, nuclear magnetic resonance) has been the most useful technology succeeding the conventional methods such as thin layer and column chromatography. In some cases, high-performance thin layer chromatography and capillary electrophoresis are also used for this purpose.
Keywords: Reviews; Quinonoids separation; Medicinal plants;

Separation methods used for Scutellaria baicalensis active components by Hua-Bin Li; Yue Jiang; Feng Chen (277-290).
Scutellaria baicalensis Georgi is one of the most widely used traditional Chinese herbal medicines. Its roots have been used for anti-inflammation, anticancer, antiviral and antibacterial infections of the respiratory and the gastrointestinal tract, cleaning away heat, moistening aridity, purging fire, detoxifying toxicosis, reducing the total cholesterol level and decreasing blood pressures. Baicalin, baicalein, wogonin and oroxylin A are its main active components. This review provides an overview of various separation, detection, and identification techniques employed for the quantitative and qualitative determination of these active components. Applications of high-performance liquid chromatography, high-speed counter-current chromatography, thin layer chromatography, capillary electrophoresis, and micellar electrokinetic capillary chromatography to the separation and determination of these active components are described. Examples of identification of these active components and their metabolites in complex matrices by high-performance liquid chromatography–mass spectrometry and gas chromatography–mass spectrometry are also presented. The advantages and limitations of these separation and identification methods are assessed and discussed.
Keywords: Reviews; Scutellaria baicalensis; Baicalin;

There is an increasing interest in the usage of chromatographic methods on the analysis of chemical compounds present in Hippophae rhamnoides L. In this paper, the chromatographic techniques applied for the determination, separation and identification of chemical compounds of H. rhamnoides L. are reviewed. We examined the existing chromatographic methods based on separations by paper and thin-layer chromatography, gas chromatography, high-performance liquid chromatography and capillary electrophoresis and also methods of detection by ultraviolet absorption, fluorescence, refractive index, electrochemical and mass spectrometry. Biological properties of the plant and its pharmacological effects and use in traditional medicine have also been reviewed.
Keywords: Reviews; Hippophae rhamnoides L.; Pharmacological effects; Chromatography;

Analysis of sugars in traditional Chinese drugs by Qingjiang Wang; Yuzhi Fang (309-324).
This review is presented of chromatography and electromigration methods currently in use to determine sugars in traditional Chinese drugs: gas chromatography (GC), high-performance liquid chromatography (HPLC), ion-exchange chromatography, gel column chromatography (GCC), paper chromatography (PC) and thin layer chromatography (TLC), capillary electrophoresis (CE) and gel electrophoresis (GEP). The detection methods combined with above separation methods including ultra-violet, mass spectra, fluorescent light, refractive index (RI), electrochemical detection are also described. For the complicacy of structural analysis of polysaccharides in traditional Chinese drugs, the hyphenation procedures concerned with this analysis are introduced in this article too.
Keywords: Sugars; Traditional Chinese drugs; Chromatography; Review;

Analytical methods to determine phytoestrogenic compounds by Qingli Wu; Mingfu Wang; James E. Simon (325-355).
The analytical methods for the determination of phytoestrogenic compounds in edible plants, plant products and biological matrices are reviewed. The detection, qualitative and quantitative methods based on different chromatographic separations of gas chromatography (GC), high-performance liquid chromatography (HPLC) and capillary electrophoresis (CE) coupled with various detections by ultraviolet absorption (UV), electrochemical detection (ED), fluorescence detection, mass spectrometry (MS) and nuclear magnetic resonance spectroscopy (NMR), as well as non-chromatographic immunoassay are each extensively examined and compared. An overview on phytoestrogen chemistry, bioactivities and health effects, plant precursors, metabolism and sample preparation is also presented.
Keywords: Review; Phytoestrogen; Analytical method; Isoflavone; Lignan;

Dibenzo[a,c]cyclooctadiene lignans of the genus Schisandra: importance, isolation and determination by Lubomír Opletal; Helena Sovová; Milena Bártlová (357-371).
The drug Wuweizi (dried fruits of Schisandra chinensis or S. sphenantherd) is one of important medicinal means used in the Oriental medicine. The lignans of dibenzo[a,c]cyklooctadiene type are major constituents, a volatile oil with mono- and ses-quiterpens, an oil, organic acids and small amounts of additional compounds are also present. The content of major lignans (schizandrin, deoxyschizandrin, gomisin A, gomisin N, γ-schizandrin, wuweizisu C) in commercially available drugs ranges usually between 3 and 5%. The present paper biefly comments the isolation and biological activity of the lignans and is especially concerned with analytical methods (TLC and HPLC) for the determination of the drug fingerprint and methods for the determination of constituents in drugs, mixtures and biological materials. HPLC methods using RP-silica bonded phases and diluted methanol, acetonitrile (or a mixture of both), are most important for these purposes. Electromigration methods are less suitable and the importance of hyphenation procedures is practically negligible.
Keywords: Schisandra chinensis; Dibenzo[a,c]cyclooctadiene lignans; Isolation;

Determination of alpha-bisabolol in human blood by micro-HPLC–ion trap MS and head space-GC–MS methods by Luigi Perbellini; Rossella Gottardo; Alessia Caprini; Federica Bortolotti; Sofia Mariotto; Franco Tagliaro (373-377).
Alpha-bisabolol is a compound present in some essential oils, widely distributed in several plants, including camomile. Two different methods for analysing an essential oil, such as alpha-bisabolol in human blood are reported: the first uses micro-liquid chromatography–electrospray ionisation-mass spectrometry (μHPLC–ESI-MS), whereas the second is based on “head space” injection coupled to gas chromatography–mass spectrometry (HS-GC–MS). For LC–ESI-MS, human blood samples, spiked with alpha-bisabolol, were extracted with hexane and evaporated to dryness under air stream. The residue was then reconstituted with methanol and injected into a C18 column, connected to an ion trap mass spectrometer equipped with an ESI source. Spectra were recorded in the positive ion, selected ion monitoring mode. The detection limit of alpha-bisabolol in blood was 0.125 μmol/l. The preparation of samples for the analysis in HS-GC–MS was limited to blood dilution with water (0.5 ml blood + 1 ml water). Head space vials were heated at 125 °C for 1 h before automatic injection. The HS-GC–MS detection limit (0.13 μmol/l) was similar to that achieved with the μHPLC–ESI-MS method. Successful tests were performed to verify if alpha-bisabolol could be directly measured by the HS-GC–MS method in different biological samples (blood, urine, faeces, homogenate tissues) from rats treated with the camomile essential oil.
Keywords: Alpha-bisabolol; Blood; μHPLC–ESI-MS method; HS-GC–MS method;

Terpenoids are natural products with an important pharmacological interest, which are present in a number of medicinal plants. The species of Sideritis genus are valuable due to their high content in those compounds and they have been used in the Mediterranean area in folk medicine as anti-inflammatory and anti-ulcer agents. The present study describes a gradient elution reversed-phase method that uses diode array detection to determine ten pharmacologically active diterpenoids occurring in 12 species of Sideritis. First, we studied the chromatographic behaviour of standard diterpenoids to analyse the variation on retention time and the chromatographic properties with the mobile phase. Standard calibration curves were generated by plotting the area of peaks against a concentration range of the compounds. Second, the validated method was applied to the analyses of hexanic and methanolic extracts from 12 species of Sideritis, which were collected from different areas of Spain. Finally, we established for this plant a relationship between their use in folk medicine and their diterpenoid content.
Keywords: Diterpenoids; Retention behaviour; Sideritis spp.; HPLC; Anti-inflammatory; Folk medicine;