Chemical markers for the quality control of herbal medicines: an overview

Gut microbiota: a new angle for traditional herbal medicine research

Traditional Herbal Medicine (THM) has been used for thousands of years, and is popular worldwide due to its effectiveness in a variety of diseases. THM has also formed the basis of the discovery of modern drugs like artemisinin and paclitaxel. However, at present, studies that focus on development in the field of THM are stagnant because currently, the effective ingredients in the herbal formulations and the ambiguity of the underlying mechanisms of action are unknown. In this review, we have investigated the studies available that focused on the efficacy, active ingredients and bioavailability of THM, and the function of gut microbiota in THM-mediated treatment of disease. We hypothesized that most THMs treat diseases via three mechanisms: (1) metabolizing into active metabolites by the action of gut microbiota, (2) regulation of gut microbiota balance, and (3) regulating the fermentation products of the gut microbes. Therefore, focusing on these aspects can help elucidate the pharmacodynamic constituents of THM preparations, and their therapeutic mechanisms of action.

Qualitative and quantitative analysis of Porana sinensis Hemsl by UHPLC-Q-Exactive MS, TLC autographic method and DART-MS

INTRODUCTION

Erycibe obtusifolia and E. schmidtii are widely used in traditional Chinese medicine (TCM) to treat joint pain and rheumatoid arthritis. With the reduction of wild E. obtusifolia and E. schmidtii resources, Porana sinensis has been widely used as a substitute. However, few studies have been conducted on the chemical composition and quality control of P. sinensis.

OBJECTIVE

To clarify the chemical composition and improve the quality control of P. sinensis.

METHODOLOGY

We developed an ultra-high performance liquid chromatography electrospray ionisation Q-Exactive Focus tandem mass spectrometry (UHPLC-ESI-Q-Exactive Focus-MS/MS) method to characterise the chemical constituents of P. sinensis. A strategy based on a combination of high-performance thin-layer chromatography (HPTLC) and direct analysis in real-time (DART) ion source was proposed for the identification of alkaloid components in P. sinensis. Thin-layer chromatography (TLC) autography for 2,2'-diphenyl-1-picrylhydrazyl free radical (DPPH˙) and TLC bioautography for xanthine oxidase were used to rapidly screen marker compounds for high-performance liquid chromatography (HPLC) determination of P. sinensis. Based on the selected marker compounds, a HPLC method for the quantitative determination of eight marker compounds in P. sinensis was developed.

RESULTS

Eighteen compounds in P. sinensis were identified by UHPLC-Q-Exactive MS. Taken together with the results of TLC autography and TLC bioautography, eight compounds were chosen as marker compounds for HPLC determination of P. sinensis. The alkaloid components in P. sinensis were identified as Baogongteng A and Baogongteng C by DART-MS.

CONCLUSION

We systematically clarified the chemical composition of P. sinensis for the first time, and potentially improved its quality control. These results should promote the application of P. sinensis as a new resource for Caulis Erycibes.

Organic Certification is Not Enough: The Case of the Methoxydecane Frankincense

Frankincense, the oleo-gum-resin of Boswellia trees, has been an important religious and medicinal element for thousands of years, and today is used extensively for essential oils. One of the most popular frankincense species is Boswellia sacra Flueck. (syn. Boswellia carteri Birdw.) from Somalia and Somaliland. Recent increases in demand have led to many areas being overharvested, emphasizing the need for incentives and monitoring for sustainable harvesting, such as certification schemes. Concurrently, a new chemical component, called methoxydecane, has emerged in oils claimed to be B. carteri, suggesting the possibility of a chemical marker of overharvesting or other stress that could aid in monitoring. To find the source of this new chemical component, we sampled resin directly from trees in areas producing the new methoxydecane chemotype. This revealed that methoxydecane comes not from Boswellia carteri, but from a newly described frankincense species, Boswellia occulta. The presence of Boswellia occulta oil in essential oil sold as pure B. carteri, including certified organic oil, emphasizes the current lack of traceability in the supply chain and the ineffectiveness of organic certification to secure purity and sustainable harvesting in wildcrafted species.

Emerging Applications of Metabolomics in Traditional Chinese Medicine Treating Hypertension: Biomarkers, Pathways and More

Hypertension is a prevalent, complex, and polygenic cardiovascular disease, which is associated with increased mortality and morbidity. Across the world, traditional Chinese medicine (TCM) constituted by herbal medicine and non-pharmacological therapies is used to assist blood pressure management. Though widely accepted in daily practice, its mechanism remains largely unknown. Recent years saw a number of studies utilizing metabolomics technologies to elucidate the biological foundation of the antihypertensive effect of TCM. Metabolomics is a relatively "young" omics approach that has gained enormous attention recently in cardiovascular drug discovery and pharmacology studies of natural products. In this review, we described the use of metabolomics in deciphering TCM diagnostic codes for hypertension and in revealing molecular events that drive the antihypertensive effect. By corroborating the diagnostic rules, there's accumulating evidence showing that metabolic profile could be the signature of different syndromes/patterns of hypertension, which offers new perspectives for disease diagnosis and efficacy optimization. Moreover, TCM treatment significantly altered the metabolic perturbations associated with hypertension, which could be a crucial mechanism of the therapeutic effect of TCM. Not only significantly rebalances the dynamics of metabolic flux, TCM but also elicits metabolic network reorganization through restoring the functions of key metabolites, and metabolic pathways. The role of TCM in regulating metabolic perturbations will be informative to researchers seeking new leads for drug discovery. This review further envisioned the promises of employing metabolomics to explore network pharmacology, host-gut microbiota interactions and metabolic reprogramming in TCM, and possible herb-drug interactions in this field in future.

Gut microbiota, a new frontier to understand traditional Chinese medicines

As an important component of complementary and alternative medicines, traditional Chinese medicines (TCM) are gaining more and more attentions around the world because of the powerful therapeutic effects and less side effects. However, there are still some doubts about TCM because of the questionable TCM theories and unclear biological active compounds. In recent years, gut microbiota has emerged as an important frontier to understand the development and progress of diseases. Together with this trend, an increasing number of studies have indicated that drug molecules can interact with gut microbiota after oral administration. In this context, more and more studies pertaining to TCM have paid attention to gut microbiota and have yield rich information for understanding TCM. After oral administration, TCM can interact with gut microbiota: (1) TCM can modulate the composition of gut microbiota; (2) TCM can modulate the metabolism of gut microbiota; (3) gut microbiota can transform TCM compounds. During the interactions, two types of metabolites can be produced: gut microbiota metabolites (of food and host origin) and gut microbiota transformed TCM compounds. In this review, we summarized the interactions between TCM and gut microbiota, and the pharmacological effects and features of metabolites produced during interactions between TCM and gut microbiota. Then, focusing on gut microbiota and metabolites, we summarized the aspects in which gut microbiota has facilitated our understanding of TCM. At the end of this review, the outlooks for further research of TCM and gut microbiota were also discussed.

Utility of alkaloids as chemical and biomarkers for quality, efficacy, and safety assessment of botanical ingredients

BACKGROUND

Selecting the appropriate chemical and bio-markers for monitoring the quality, efficacy, and safety is critical for efficient and reliable assessment of traditional medicines derived from botanical sources. Chemical markers have been implicated primarily in establishing the analytical methodologies aiming at verification of the botanical sources of the raw materials, the extracts, and the finished products such as botanical dietary supplements and nutraceuticals. In addition, they have been employed in differentiation between crude or raw (unprocessed) and processed plant extracts, and identification as well as determination of potential toxicants and adulterants in herbal medicines. Additionally, these chemical markers are utilized for selection of efficient methods for extraction of plants. Further, biomarkers have been exploited in determination of the pharmacokinetic properties of bioactive herbal constituents. Alkaloids, unlike other plant constituents, are uniquely characterized by having basic properties, and possessing substantial and diverse pharmacological effects. These features make alkaloids attractive components for functioning as chemical and biomarkers in determining the quality of botanical ingredients where this class of phytochemicals prevail or is responsible for lending biological effects.

PURPOSE

The aim of the review is to exhibit the function of alkaloids as biomarkers and chemical markers in the evaluation of quality, efficacy, and safety of medicinal herbs and their commercial products.

METHODS

Literature acquisition was accomplished using the most commonly accessed scholarly search engines including SciFinder, PubMed, and Google Scholar. Secondly, the full-texts which are relevant to the topic were included in this review. This was followed by a thorough and detailed analysis of the collected information.

RESULTS

The literature search with main emphasis on the roles of alkaloids in the evaluation of quality, efficacy and safety of herbal medicines was evaluated to provide all succinct information in one place. Compilation of such critical information is expected to help the reader to appreciate alkaloids as important markers in the quality control of herbal drugs and products.

CONCLUSION

The current review article covers the fundamental roles played by alkaloids as chemical and biomarkers in assessing the essential parameters of the quality of botanical ingredients, as briefly described earlier. The utilization of alkaloids as biomarkers to determine the efficacy-linked pharmacokinetic parameters is limited to reviewing studies on human subjects.

Recent Development of Quality Control Methods for Herbal Derived Drug Preparations

Pharmaceutical industries should apply rigorous QC (quality control) to ensure the consistency, safety, and efficacy of their herbal derived drug-preparations. QC must be performed at every stage of the production line i.e. incoming raw materials, extractions, in-process control, finished products and keeping samples. Due to the complex nature of the chemical content of herbal drugs, two approaches to QC should be taken, that is quantitative determination of the selected marker(s) compound(s), and metabolite profiling. Contamination of herbal medicines by heavy metals, pesticides, toxic metabolites, microbial toxins, pathogenic microorganisms and other foreign matter should also be evaluated. A combination of chemical profiling and multivariate analysis (MVA) is recommended as the QC tool for the botanical identification method (BIM) of herbs, extracts, herb materials, and herbal drug preparations. Microscopic methods, DNA profiling or chemical marker(s) are not recommended for use as the sole BIM due to the lack of specificity. Only markers that meet certain criteria i.e. quality active (QA) markers can be utilized as a QC tool. The limit specification range of markers used as QC tools should be described in the analytical target profile (ATP). To gain reliable results of any analysis that has been performed at any QC laboratory, the analysis method must be validated according to the newest guidance. Sample detection limit of any toxic compound(s) should be lower than its cut-off value and MPL. The reliability of any results of analysis of a QC laboratory must be evaluated by using QC-samples for each series of measurements.

Quantification of Multifunctional Dipeptide YA from Oyster Hydrolysate for Quality Control and Efficacy Evaluation

YA is an angiotensin-I-converting enzyme- (ACE-) inhibitory peptide from oyster hydrolysate with antihypertensive activity. Its antioxidant and anti-inflammatory activity were investigated in this study. YA can dose-dependently quench DPPH and ABTS radical and inhibit lipopolysaccharide-induced nitric oxide in RAW 264.7 cells. YA is a multifunctional peptide and was selected as an indicator for quality control and efficacy evaluation of oyster hydrolysate. A practical HPLC/UV assay for YA quantification was developed and validated. It was proved to be accurate and reliable, according to parameters such as specificity, linearity, precision, and accuracy. The quantity results of YA showed that the stage of enzymatic hydrolysis was a critical control point for quality control; the efficacy of oyster hydrolysate can be enhanced after digested in the gastrointestinal tract due to the release of YA by brush border peptidases. Therefore, YA from oyster hydrolysate is a potential bioactive ingredient for functional foods to combat hypertension.

Simultaneous Quantification of Eight Marker Compounds in Yongdamsagan-Tang Using a High-Performance Liquid Chromatography Equipped with Photodiode Array Detector

Yongdamsagan-tang (YDSGT) has been used clinically for the treatment of acute- and chronic-urethritis, cystitis, orchitis and hypertension in Korea. In this study, a powerful method based on high-performance liquid chromatography (HPLC) with photodiode array (PDA) detection was established and validated for the quantitative analysis of eight components: chlorogenic acid, gentiopicroside, liquiritin apioside, liquiritin, nodakenin, baicalin, wogonoside and glycyrrhizin in YDSGT extract. The compounds were separated with a Gemini C18 analytical column (column temperature: 40°C; mobile phase: 0.1% (v/v) aqueous trifluoroacetic acid (A) and acetonitrile (B); flow rate: 1.0 mL/min; injection volume: 10 μL). The PDA detector scanned the range 190-800 nm and the marker compounds were monitored at 254, 275, 325 and 335 nm. The correlation coefficients of all compounds were 1.000 and the results showed excellent linearity. The lower limits of detection and quantification of the analytes were 0.01-0.09 μg/mL and 0.03-0.28 μg/mL, respectively. The extraction recoveries of the marker compounds were 98.13-103.86%, with relative standard deviation values not exceeding 2.10%. The precision of intra- and inter-day measurements were 0.09-1.78% and 0.12-2.09%, respectively. The content of the eight marker compounds in the freeze-dried YDSGT extract were 1.41-23.71 mg/g.

Validation of Chromatographic Methods of Analysis: Application for Drugs That Derived From Herbs

It is well known that the quality control (QC) of drugs derived from herbs (DDHs) has two main problems: first, DDHs are chemically complex mixtures, and second, the chemical contents of raw plant materials are affected by the site of cultivation, age of plants, methods of harvesting, and processing. QC is used by manufacturers to ensure the consistency, safety, and efficacy of the DDHs. QC of DDHs can be performed by two approaches, namely, marker-oriented and chemical pattern-oriented (metabolite profiling) using chromatographic methods. For having reliable results of any chemical analysis that will be performed in the QC laboratory, the method of analysis must be validated first before it can be routinely applied. Parameters of the validation method that should be evaluated for marker-oriented approach are stability, selectivity, linearity, trueness, precision, and robustness/ruggedness, while for metabolite profiling approach stability, intra- and interday precisions should be determined. Determination of instrumental and sample detection limit (DL), quantification limit (QL), and cutoff value is described in this review. Some relatively new validation methods that could correlate trueness and precision will be also discussed. The importance and application of metabolite profiling for a QC laboratory at pharmaceutical industry are discussed.

Antinociceptive and anti-inflammatory activities of the Jatropha isabellei dichloromethane fraction and isolation and quantitative determination of jatrophone by UFLC-DAD

CONTEXT

Jatropha isabellei Müll. Arg. (Euphorbiaceae) has been used in the traditional medicine to treat arthritis.

OBJECTIVE

To evaluate the anti-inflammatory and antinociceptive activities of the dichloromethane fraction (DF_Ji) from underground parts of J. isabellei, and to develop an analytical method to quantify the diterpene jatrophone.

MATERIALS AND METHODS

Anti-inflammatory and antinociceptive activities of the DF_ji were determined by an acute arthritis model through assessment of the paw elevation time (PET) and articular diameter (AD) of Wistar rats treated orally (50, 100 or 200 mg/kg in a single-dose), and intravenously (0.1, 1, 10, 25 or 50 mg/kg in a bolus administration). The isolation of jatrophone from the DF_ji was carried out and confirmed by spectroscopic techniques. A UFLC-DAD method was developed and validated.

RESULTS

When orally administered, the highest dose (200 mg/kg) of DF_Ji was able to significantly reduce the PET to 24.8 ± 1.4 s (p < 0.01), when compared with the control group (33.7 ± 1.8 s). The administration of the intravenous dose of 10 mg/kg reduced the PET to 14.8 ± 0.3 s (p < 0.001). The oral and intravenous administration of the DF_Ji at dose of 200 and 10 mg/kg significantly prevented the formation of edema, reducing the AD in 25.3% and 32.5% (p < 0.01), respectively. The UFLC-DAD method allowed the quantification of jatrophone, which was found to be around 90 μg/mg of fraction.

DISCUSSION AND CONCLUSION

The DF_Ji displayed antinociceptive and antiedematogenic activities, representing a promising plant product for the arthritis treatment.

Antifungal photosensitive activity of Porophyllum obscurum (Spreng.) DC.: Correlation of the chemical composition of the hexane extract with the bioactivity

We report Porophyllum obscurum as a source of new photosensitizers with potential use in Photodynamic Therapy as an alternative for oropharyngeal candidiasis treatment. The antifungal photosensitive activity of different extracts from P. obscurum was evaluated by using microdilution and bioautographic assays. The Minimum Fungicidal Concentration for hexanic extract under UV-A irradiation was 0.98μg/mL, but it was inactive in experiments without irradiation. The bioassay-guided fractionation of this extract led to the isolation of four thiophenes responsible for the photosensitive activity: 2,2':5'2″terthiophene, 5-(3-buten-1-ynyl)-2,2'-bithiophene, 5-(4-acetoxy-1-butenyl)-2,2'- bithiophene and 5-(4-hydroxy-1-butenyl)-2,2'- bithiophene, with Minimum Fungicidal Concentrations ranging 0.24-7.81μg/mL under UV-A irradiation. The activity of the hexanic extract was evaluated against 25 clinical strains of Candida spp. isolates as etiological agents of oropharyngeal candidiasis. No differences in susceptibility were observed in strains resistant and susceptible to conventional antifungal drugs. Qualitative and quantitative chemical analyses of seven samples of P. obscurum collected in four different phenological stages were carried out showing that full flowering stage possesses the highest thiophenes content. These data also allowed us to establish a correlation between the thiophene composition of the different extracts and their antifungal photosensitive activity, according to a second order polynomial model with the equation: y=11.2603-0.6831*x+0.0108*x². The thiophenes isolated were the responsible of antifungal photosensitive activity and can be used for the future standardization of the extract. Results showed that P. obscurum hexanic extract could be potentially developed as an Herbal Medicinal Product to be applied as a photosensitizer in Photodynamic Therapy.

Metabolomics approach reveals annual metabolic variation in roots of Cyathula officinalis Kuan based on gas chromatography-mass spectrum

BACKGROUND

Herbal quality is strongly influenced by harvest time. It is therefore one of crucial factors that should be well respected by herbal producers when optimizing cultivation techniques, so that to obtain herbal products of high quality. In this work, we paid attention on one of common used Chinese herbals, Cyathula officinalis Kuan. According to previous studies, its quality may be related with growth years because of the variation of several main bioactive components in different growth years. However, information about the whole chemical composition is still scarce, which may jointly determine the herbal quality.

METHODS

Cyathula officinalis samples were collected in 1-4 growth years after sowing. To obtain a global insight on chemical profile of herbs, we applied a metabolomics approach based on gas chromatography-mass spectrum. Analysis of variance, principal component analysis, partial least squares discriminant analysis and hierarchical cluster analysis were combined to explore the significant difference in different growth years.

RESULTS

166 metabolites were identified by using gas chromatography-mass spectrum method. 63 metabolites showed significant change in different growth years in terms of analysis of variance. Those metabolites then were grouped into 4 classes by hierarchical cluster analysis, characterizing the samples of different growth ages. Samples harvested in the earliest years (1-2) were obviously differ with the latest years (3-4) as reported by principal component analysis. Further, partial least squares discriminant analysis revealed the detail difference in each growth year. Gluconic acid, xylitol, glutaric acid, pipecolinic acid, ribonic acid, mannose, oxalic acid, digalacturonic acid, lactic acid, 2-deoxyerythritol, acetol, 3-hydroxybutyric acid, citramalic acid, N-carbamylglutamate, and cellobiose are the main 15 discrimination metabolites between different growth years.

CONCLUSION

Harvest time should be well considered when producing C. officinalis. In order to boost the consistency of herbal quality, C. officinalis is recommended to harvest in 4th growth year. The method of GC-MS combined with multivariate analysis was a powerful tool to evaluate the herbal quality.

Induction of apoptosis in human hepatocellular carcinoma cells by extracts of Lannea coromandelica (Houtt.) Merr. and Diospyros castanea (Craib) Fletcher

Background

Herbal plants are a preferred source of anticancer agents. This study aims to screen the anticancer activity of a crude extract of twigs of (a) Bombax anceps Pierre var. anceps (BA); (b) Catunaregam tomentosa (Blume ex DC.) Tirveng. (CT); (c) Erythrophleum succirubrum Gagnep. (ES); (d) Lannea coromandelica (Houtt.) Merr. (LC); and (e) leaves and (f) twigs of Diospyros castanea (Craib) Fletcher (DC).

Methods

The 50 % ethanol–water extracts were prepared from each plant sample. In vitro anticancer effects of six extracts on the human hepatocellular carcinoma cell line (HepG2) in terms of cytotoxicity were investigated by neutral red assay, apoptosis induction by 4′,6-diamidino-2-phenylindole (DAPI) staining, and DNA fragmentation by agarose gel electrophoresis. Normal Vero cells were tested for comparison and to determine cancer selectivity. Gas chromatography–mass spectrometry analysis was performed to identify the compounds in the extracts.

Results

The six crude extracts had different cytotoxicities and were classified into three groups based on their IC₅₀ value and selectivity index (SI). DC (twig) crude extract had both a high cytotoxicity and SI toward HepG2 cells comparable to melphalan (P = 0.023). The crude extracts of DC (leaves), LC (twig), and BA (twig) had moderate cytotoxicity and a lower SI. Although all crude plant extracts induced apoptosis in more than 50 % of the DAPI-positive apoptotic HepG2 cells, only DC (twig) and LC (twig) showed laddering in the DNA fragmentation assay. 2-Palmitoylglycerol was the major compound common to both. Pyrogallol and lupeol were the major compounds in DC (twig) crude extract. Hexadecanoic acid and octadecenoic acid were the major compounds in LC (twig) crude extract, which had high toxicity but low selectivity.

Conclusion

Ethanolic extracts from DC and LC twigs induced apoptosis in the HepG2 cell line. Pyrogallol and lupeol in DC (twig) might be responsible for the cytotoxicity toward the HepG2 cancer cells.

Simultaneous determination of nine bioactive compounds in Yijin-tang via high-performance liquid chromatography and liquid chromatography-electrospray ionization-mass spectrometry

Background

Yijin-tang (YJ) has been used traditionally for the treatment of cardiovascular conditions, nausea, vomiting, gastroduodenal ulcers, and chronic gastritis. In this study, a simple and sensitive high-performance liquid chromatography (HPLC) method was developed for the quantitation of nine bioactive compounds in YJ: homogentisic acid, liquiritin, naringin, hesperidin, neohesperidin, liquiritigenin, glycyrrhizin, 6-gingerol, and pachymic acid.

Methods

Chromatographic separation of the analytes was achieved on an RS Tech C₁₈ column (4.6 mm × 250 mm, 5 μm) using a mobile phase composed of water containing 0.1% (v/v) trifluoroacetic acid (TFA) and acetonitrile with a gradient elution at a flow rate of 1.0 mL/min.

Results

Calibration curves for all analytes showed good linearity (R² ≥ 0.9995). Lower limits of detection and lower limits of quantification were in the ranges of 0.03–0.17 μg/mL and 0.09–0.43 μg/mL, respectively. Relative standard deviations (RSDs; %) for intra- and interday assays were < 3%. The recovery of components ranged from 98.09% to 103.78%, with RSDs (%) values ranging from 0.10% to 2.59%.

Conclusion

This validated HPLC method was applied to qualitative and quantitative analyses of nine bioactive compounds in YJ and fermented YJ, and may be a useful tool for the quality control of YJ.

Rational quality assessment procedure for less-investigated herbal medicines: Case of a Congolese antimalarial drug with an analytical report

Herbal medicines are the most globally used type of medical drugs. Their high cultural acceptability is due to the experienced safety and efficiency over centuries of use. Many of them are still phytochemically less-investigated, and are used without standardization or quality control. Choosing SIROP KILMA, an authorized Congolese antimalarial phytomedicine, as a model case, our study describes an interdisciplinary approach for a rational quality assessment of herbal drugs in general. It combines an authentication step of the herbal remedy prior to any fingerprinting, the isolation of the major constituents, the development and validation of an HPLC-DAD analytical method with internal markers, and the application of the method to several batches of the herbal medicine (here KILMA) thus permitting the establishment of a quantitative fingerprint. From the constitutive plants of KILMA, acteoside, isoacteoside, stachannin A, and pectolinarigenin-7-O-glucoside were isolated, and acteoside was used as the prime marker for the validation of an analytical method. This study contributes to the efforts of the WHO for the establishment of standards enabling the analytical evaluation of herbal materials. Moreover, the paper describes the first phytochemical and analytical report on a marketed Congolese phytomedicine.

The Importance of Method Selection in Determining Product Integrity for Nutrition Research

The American Herbal Products Association estimates that there as many as 3000 plant species in commerce. The FDA estimates that there are about 85,000 dietary supplement products in the marketplace. The pace of product innovation far exceeds that of analytical methods development and validation, with new ingredients, matrixes, and combinations resulting in an analytical community that has been unable to keep up. This has led to a lack of validated analytical methods for dietary supplements and to inappropriate method selection where methods do exist. Only after rigorous validation procedures to ensure that methods are fit for purpose should they be used in a routine setting to verify product authenticity and quality. By following systematic procedures and establishing performance requirements for analytical methods before method development and validation, methods can be developed that are both valid and fit for purpose. This review summarizes advances in method selection, development, and validation regarding herbal supplement analysis and provides several documented examples of inappropriate method selection and application.

Drug discovery of neurodegenerative disease through network pharmacology approach in herbs

Neurodegenerative diseases, referring to as the progressive loss of structure and function of neurons, constitute one of the major challenges of modern medicine. Traditional Chinese herbs have been used as a major preventive and therapeutic strategy against disease for thousands years. The numerous species of medicinal herbs and Traditional Chinese Medicine (TCM) compound formulas in nervous system disease therapy make it a large chemical resource library for drug discovery. In this work, we collected 7362 kinds of herbs and 58,147 Traditional Chinese medicinal compounds (Tcmcs). The predicted active compounds in herbs have good oral bioavailability and central nervous system (CNS) permeability. The molecular docking and network analysis were employed to analyze the effects of herbs on neurodegenerative diseases. In order to evaluate the predicted efficacy of herbs, automated text mining was utilized to exhaustively search in PubMed by some related keywords. After that, receiver operator characteristic (ROC) curves was used to estimate the accuracy of predictions. Our study suggested that most herbs were distributed in family of Asteraceae, Fabaceae, Lamiaceae and Apocynaceae. The predictive model yielded good sensitivity and specificity with the AUC values above 0.800. At last, 504 kinds of herbs were obtained by using the optimal cutoff values in ROC curves. These 504 herbs would be the most potential herb resources for neurodegenerative diseases treatment. This study would give us an opportunity to use these herbs as a chemical resource library for drug discovery of anti-neurodegenerative disease.

The relevance of pharmacognosy in pharmacological research on herbal medicinal products

As all medicines, herbal medicinal products are expected to be safe, effective, and of appropriate quality. However, regulations on herbal medicinal products vary from country to country, and herbal preparations do occur not only in the form of medicinal products but also as less strictly regulated product groups like dietary supplements. Therefore, it is not always easy for the consumers to discriminate high-quality products from low-quality products. On the other hand, herbal medicines have many special features that distinguish them from conventional medicinal products. Plants are complex multicomponent mixtures; in addition, their phytochemical composition is not constant because of inherent variability and a plethora of external influences. Therefore, the production process of an herbal medicinal product needs to be strictly monitored. First of all, the starting materials need to be correctly authenticated and free of adulterants and contaminants. During plant growth, many factors like harvest season and time, developmental stage, temperature, and humidity have a strong impact on plant metabolite production. Also, postharvest processing steps like drying and storage can significantly alter the phytochemical composition of herbal material. As the production of many phytopharmaceuticals includes an extraction step, the extraction solvent and conditions need to be optimized in order to enrich the bioactive constituents in the extract. The quality of finished preparations needs to be determined either on the basis of marker constituents or on the basis of analytical fingerprints. Thus, all production stages should be accompanied by appropriate quality assessment measures. Depending on the particular task, different methods need to be applied, ranging from macroscopic, microscopic, and DNA-based authentication methods to spectroscopic methods like vibrational spectroscopy and chromatographic and hyphenated methods like HPLC, GC-MS and LC-MS. Also, when performing pharmacological and toxicological studies, many features inherent in herbal medicinal products need to be considered in order to guarantee valid results: concerning in vitro studies, difficulties are often related to lacking knowledge of ADME characteristics of the bioactive constituents, nuisance compounds producing false positive and false negative results, and solubility problems. In in vivo animal studies, the route of administration is a very important issue. Clinical trials on herbal medicinal products in humans very often suffer from a poor reporting quality. This often hampers or precludes the pooling of clinical data for systematic reviews. In order to overcome this problem, appropriate documentation standards for clinical trials on herbal medicinal products have been defined in an extension of the CONSORT checklist. This article is part of a Special Issue entitled "Botanicals for Epilepsy".

HPLC-PDA Method for Simultaneous Determination of Nine Marker Components in Banhasasim-Tang

A simple and accurate high-performance liquid chromatography-photodiode array (HPLC-PDA) detection method has been developed and validated for simultaneous determination of nine components-liquiritin, coptisine, baicalin, palmatine, berberine, wogonoside, baicalein, glycyrrhizin and wogonin-in the traditional Korean formula, Banhasasim-tang decoction. A Gemini C18 analytical column was used to separate the nine constituents and kept at 40°C by gradient elution with 0.1% (v/v) trifluoroacetic acid in distilled water (A) and acetonitrile (B) as mobile phases. The flow rate was 1.0 mL/min and the injection volume was 10 µL. The PDA detection wavelengths were set at 254, 275 and 350 nm. Calibration curves of all compounds showed good linearity with coefficients of determination ≥0.9998 within the test ranges. The limits of detection and quantification of all compounds were in the range 0.01-0.09 and 0.03-0.30 µg/mL, respectively. All recoveries of the nine marker compounds ranged from 98.65 to 103.22% with relative standard deviation (RSD) values <1.25%. The RSDs of intraday and interday precision were <1.13 and 1.83%, respectively. The concentrations of the nine marker constituents were 0.19-41.09 mg/g.

Advanced development in phytochemicals analysis of medicine and food dual purposes plants used in China (2011-2014)

In 2011, we wrote a review for summarizing the phytochemical analysis (2006-2010) of medicine and food dual purposes plants used in China (Zhao et al., J. Chromatogr. A 1218 (2011) 7453-7475). Since then, more than 750 articles related to their phytochemical analysis have been published. Therefore, an updated review for the advanced development (2011-2014) in this topic is necessary for well understanding the quality control and health beneficial phytochemicals in these materials, as well as their research trends.

Identification of common horsetail (Equisetum arvense L.; Equisetaceae) using Thin Layer Chromatography versus DNA barcoding

The global herbal products market has grown in recent years, making regulation of these products paramount for public healthcare. For instance, the common horsetail (Equisetum arvense L.) is used in numerous herbal products, but it can be adulterated with closely related species, especially E. palustre L. that can produce toxic alkaloids. As morphology-based identification is often difficult or impossible, the identification of processed material can be aided by molecular techniques. In this study, we explore two molecular identification techniques as methods of testing the purity of these products: a Thin Layer Chromatography approach (TLC-test) included in the European Pharmacopoeia and a DNA barcoding approach, used in recent years to identify material in herbal products. We test the potential of these methods for distinguishing and identifying these species using material from herbarium collections and commercial herbal products. We find that both methods can discriminate between the two species and positively identify E. arvense. The TLC-test is more cost- and time-efficient, but DNA barcoding is more powerful in determining the identity of adulterant species. Our study shows that, although DNA barcoding presents certain advantages, other established laboratory methods can perform as well or even better in confirming species' identity in herbal products.

Chemistry and pharmacology of the herb pair Flos Lonicerae japonicae-Forsythiae fructus

The Chinese medicine herb pair Flos Lonicerae japonicae (FLJ) and Forsythiae fructus (FF), is a representative heat-clearing (qing re) and detoxifying (jie du) combination that exhibits many pharmacological activities, including antibacterial, antiviral, antitumor, anti-inflammatory, and antioxidant effects. Extensive phytochemical studies have identified a series of bioactive compounds, such as chlorogenic acid from FLJ and forsythoside A from FF. This article provides a comprehensive review on the chemical and pharmacological principles of the traditional functions of FLJ-FF, and sheds light on further developments of this herb pair.

Choosing chemical markers for quality assurance of complex herbal medicines: Development and application of the herb MaRS criteria

With increasing use of herbal medicines for chronic or serious illness, relevant quality assurance methods are essential for making claims of therapeutic benefit. Adequate demonstration of safety and efficacy based on chemical composition and ensuring consistency between manufactured batches is critical. To date, there has been no uniform standard approach or detailed framework provided to industry for selecting relevant chemical markers used to standardize herbal products. We developed the Herbal Marker Ranking System (Herb MaRS) providing guidance on prioritizing the selection of chemical markers for quality control of complex multi-herb mixtures, while also taking into account the bioactivity in relation to the symptoms of the disease and its concentration in the formula. We apply the Herb MaRS evaluation criteria to a seven-herb formulation for the treatment of irritable bowel syndrome with constipation. Our ranking scale accommodates the clinical and pharmacological use of the formulation and its claimed indications.

Safety evaluation of local weight-gain formulas in the Saudi Arabian markets

BACKGROUND

The utilization of herbal formulas is continuously increasing on the global level. However, assessment of contamination and impurities is the leading challenge in the use of herbal medicines.

OBJECTIVE

Assessment of therapeutic application in relation to herbal formulas usage for reducing weight is the objective for this investigation.

RESULTS

Reduced dietary fibers and fats are common outcomes of herbal usage. 9.8% of the mixtures were contaminated because of lead. However, investigation has indicated <10 microbial counts in herbal products. Increased levels of calcium, minerals, fibers, and lead traces have been identified in the herbals; however, products lacked nicotinamide, riboflavin, and vitamin C.

CONCLUSION

It was concluded that majority of herbal products were pure and uncontaminated in order to reduce the complications of obesity efficiently.

Optimization of ultrasound extraction of Alisma orientalis polysaccharides by response surface methodology and their antioxidant activities

Rhizoma alismatis (the rhizome of Alisma orientalis) polysaccharides (RAP) have been reported to have a variety of important biological activities. However, effective extraction of RAP has been an unsolved issue. In this study, we used an ultrasound method for high yield extraction of RAP and optimized the conditions using the response surface methodology (RSM). Following multiple regression analyses of the experimental results, we applied the 3-D response surface and the contour plots to determine the optimal conditions, which were found to be ultrasound treatment at 76.1°C for 75.2 min, and water to material ratio at 30.1 ml/g. Under such conditions, the yield was 6.90% which was much higher than traditional hot water extraction yield (3.41%). The fractionated RAPs following stepwise ethanol precipitation showed strong antioxidant activities. The results indicated that ultrasound extraction was a very effective method for the extraction of RAP and the polysaccharides could be explored as a potential antioxidant agent for use in medicine or functional food.

Quality control of traditional Chinese medicines: a review

Traditional Chinese medicines (TCMs) are in great demand all over the world, especially in the developing world, for primary health care due to their superior merits such as low cost, minimal side effects, better cultural acceptability, and compatibility with humans. However, Chinese medicines consist of several herbs which may contain tens, hundreds, or even thousands of constituents. How these constituents interact with each other, and what the special active ones are, may be the biggest bottleneck for the modernization and globalization of TCMs. Valid methods to evaluate the quality of TCMs are therefore essential and should be promoted and be developed further through advanced separation and chromatography techniques. This paper reviews the strategies used to control the quality of TCMs in a progressive perspective, from selecting single or several ingredients as the evaluation marker, to using different kinds of chromatography fingerprint methods. In summary, the analysis and quality control of TCMs are developing in a more effective and comprehensive manner to better address the inherent holistic nature of TCMs.

Assessment of peeling of Astragalus roots using 1H NMR- and UPLC-MS-based metabolite profiling

A metabolomic analysis was performed to examine the postharvest processing of Astragalus membranaceus roots with a focus on the peeling procedure using (1)H NMR and UPLC-MS analyses. Principal component analysis (PCA) score plots from the (1)H NMR and UPLC-MS data showed clear separation between peeled and unpeeled Astragalus roots. Peeled roots exhibited significant losses of several primary metabolites, including acetate, alanine, arginine, caprate, fumarate, glutamate, histidine, N-acetylaspartate, malate, proline, sucrose, trigonelline, and valine. In contrast, the peeled roots contained higher levels of asparagine, aspartate, and xylose, which are xylem-related compounds, and formate, which is produced in response to wound stress incurred during postharvest processing. In addition, the levels of isoflavonoids and astragalosides were significantly reduced in peeled Astragalus root. These results demonstrate that metabolite profiling based on a combination of (1)H NMR and UPLC-MS analyses can be used to evaluate peeling procedures used in the postharvest processing of herbal medicines.

Rapid discrimination of Herba Cistanches by multi-step infrared macro-fingerprinting combined with soft independent modeling of class analogy (SIMCA)

Herba Cistanche, an important Chinese herbal medicine, has common four species, Cistanche deserticola (CD), Cistanche tubulosa (CT), Cistanche salsa (CS) and Cistanche sinensis (CSN) which have been frequent mixed used. To clarify the sources of Herba Cistanches and ensure the clinical efficacy and safety, a method combing IR macro-fingerprinting with statistical pattern recognition was developed to analyze and discriminate the four species of Herba Cistanche. By comparing FT-IR, second derivative spectral fingerprints via group-peak matching, the similarity to CD and total saccharides (TS) followed an increasing sequence, CT<CSN<CS<CD, whereas that to total glycosides (TG) followed a decreasing order, CT>CSN>CS>CD. Characteristic fingerprints of their 2D-IR correlation spectra in 1750-1000 cm(-1) have confirmed the above findings in a more intuitive way. In terms of sources for phenylethanoid glycosides (PhGs), CT can be an ideal alternative species. However, in terms of using them as a whole, more pharmacological study should be conducted due to the different ratios of their chemical constituents, which is also applicable to CSN and CS. Moreover, the four species (179 samples) has been objectively classified by SIMCA based on IR macro-fingerprints.

Ixeris dentata-induced regulation of amylase synthesis and secretion in glucose-treated human salivary gland cells

The endoplasmic reticulum (ER) is an organelle which controls synthesis of secretory and membrane proteins. Alterations in protein folding capacity, leading to ER stress, can be observed in patients with diabetes and related diseases such as xerostomia. The objectives of this study were to investigate the effects of Ixeris dentata (IXD) extract, which has been used for diabetes treatment, and compounds purified from IXD, 8-epidesacylcynaropicrin-3-O-beta-glucopyranoside (ID-57D), on amylase synthesis and secretion in human salivary gland (HSG) cells exposed to a high concentration of glucose. A high concentration of glucose in the experimental medium of cultured cells can model diabetes in vitro. IXD extracts and ID-57D increased oxidative folding-associated protein expression, including p-IRE-1α, PDI and ERO-1α, with the enhanced oxidative folding pattern seen in HSG cells transiently exposed to a high concentration of glucose. Moreover, the treatments reduced the ER stress response, such as the expression of GRP78, maintaining amylase synthesis and secretion in chronically glucose-exposed HSG cells. This study suggests the potential therapeutic value of IXD extract for the treatment of diabetes or its complications such as xerostomia.

The current status and trend of clinical pharmacology in developing countries

BACKGROUND

Several international forums for promoting clinical pharmacology in developing countries have been held since 1980, and several clinical pharmacology programmes targeting developing countries were instituted such that the status of clinical pharmacology in developing countries is not where it was 50 years ago. Therefore, a survey and an appraisal of the literature on the current status of clinical pharmacology in developing countries were undertaken with a hope that it would enable development of appropriate strategies for further promotion of clinical pharmacology in these countries.

METHODS

First, nine determinants (or enabling factors) for running a successful clinical pharmacology programme were identified, i.e., disease burden, drug situation, economic growth, clinical pharmacology activities, recognition, human capital, government support, international collaboration, and support for traditional/alternative medicines. These factors were then evaluated with regard to their current status in the developing countries that responded to an electronic questionnaire, and their historical perspective, using the literature appraisal. From these, a projected trend was constructed with recommendations on the way forward.

RESULTS

Clinical pharmacology services, research and teaching in developing countries have improved over the past 50 years with over 90% of countries having the appropriate policies for regulation and rational use of medicines in place. Unfortunately, policy implementation remains a challenge, owing to a worsening disease burden and drug situation, versus fewer clinical pharmacologists and other competing priorities for the national budgets. This has led to a preference for training 'a physician clinical pharmacologist' in programmes emphasizing local relevancy and for a shorter time, and the training of other professionals in therapeutics for endemic diseases (task shifting), as the most promising strategies of ensuring rational use of medicines.

CONCLUSION

Clinical pharmacology in developing countries is advancing in a different way to that in the developed world and continuing support for these efforts will go a long way in promoting improved health for all.

Herbal drug regulation and commercialization: an Indian industry perspective

OBJECTIVES

To assess the constraints for Indian herbal drug industry with respect to manufacturing and commercialization of herbal medicines.

METHODS

A questionnaire-based survey was conducted to obtain primary data on challenges faced during production, commercialization, and marketing approval for traditional or herbal drugs in India and abroad. Responses were collected from 150 companies by email, telephone, and in-person interviews from June 2009 to August 2010 and were analyzed to draw appropriate conclusions.

RESULTS

The survey result showed that differing regulatory requirements and the limited market in foreign countries are the major hindrances for exporting. Standardization and quality control of raw materials and herbal formulations emerged as the major challenge for Indian herbal drug manufacturing firms. Insufficient regulatory guidelines, particularly guidelines for good manufacturing practices; nonimplementation of good agricultural and collection practices; and weak implementation of the Drugs and Cosmetics Act of 1940 are considered major drawbacks for the Indian herbal industry.

CONCLUSIONS

Proper implementation of the Drugs and Cosmetics Act of 1940, development of more elaborate guidelines on quality control aspects, and development of marker-based standards are needed to produce safe and effective herbal medicines in India. Because evidence-based studies are becoming increasingly essential for establishing the safety and efficacy of herbal products in the domestic and export market, more focus should be placed on scientific and technological advancement in the field of herbal medicine. Regulatory harmonization becomes essential to mitigate the delays in commercialization across countries.

Development, optimisation and validation of a stability-indicating HPLC method of achyrobichalcone quantification using experimental designs

INTRODUCTION

Achyrobichalcone is a new biflavonoid found in Achyrocline satureioides. It is structurally similar to other bioactive bichalcones that were proven to exert anti-cancer activity. Recently we isolated several achyrobichalcone batches on a semi-preparative scale, showing the need to assess the quality and stability of this substance by analytical methods.

OBJECTIVE

To develop and validate a stability-indicating HPLC method of achyrobichalcone quantification using experimental designs.

METHOD

The method was developed and optimised by Box-Behnken design using column temperature, flow rate and acetonitrile content in the mobile phase as factors and system suitability parameters as responses. Validation parameters were determined according to official compendiums. Robustness was determined by Plackett-Burman design. Stability of achyrobichalcone was assessed in alkaline, acid, oxidative, thermal and photolytic stress conditions.

RESULTS

The ideal chromatographic conditions were defined from the optimisation: 37 % of acetonitrile, flow rate of 1.2 mL/min and 33°C temperature. All factors were significant for the resolution between achyrobichalcone and impurities peaks and for the retention factor. The mathematical model developed exhibited a good predictive capacity, and the design proved suitable. The HPLC method was successfully validated, being linear, specific, accurate and precise. The robustness test revealed that the flow rate and detection wavelength should be strictly controlled, as they affect achyrobichalcone concentration. The analyte was unstable only in alkaline media.

CONCLUSION

The new method developed affords evaluation of the quality of achyrobichalcone obtained by isolation, and indicates the stability of the molecule under various stress conditions.

Establishing the pharmaceutical quality of Chinese herbal medicine: a provisional BCS classification

The Biopharmaceutical Classification System (BCS), which is a scientific approach to categorize active drug ingredient based on its solubility and intestinal permeability into one of the four classes, has been used to set the pharmaceutical quality standards for drug products in western society. However, it has received little attention in the area of Chinese herbal medicine (CHM). This is likely, in part, due to the presence of multiple active components as well as lack of standardization of CHM. In this report, we apply BCS classification to CHMs provisionally as a basis for establishing improved in vitro quality standards. Based on a top-200 drugs selling list in China, a total of 31 CHM products comprising 50 official active marker compounds (AMCs) were provisionally classified according to BCS. Information on AMC content and doses of these CHM products were retrieved from the Chinese Pharmacopoeia. BCS parameters including solubility and permeability of the AMCs were predicted in silico (ACD/Laboratories). A BCS classification of CHMs according to biopharmaceutical properties of their AMCs is demonstrated to be feasible in the current study and can be used to provide a minimum set of quality standards. Our provisional results showed that 44% of the included AMCs were classified as Class III (high solubility, low permeability), followed by Class II (26%), Class I (18%), and Class IV (12%). A similar trend was observed when CHMs were classified in accordance with the BCS class of AMCs. Most (45%) of the included CHMs were classified as Class III, followed by Class II (16%), Class I (10%), and Class IV (6%); whereas 23% of the CHMs were of mixed class due to the presence of multiple individual AMCs with different BCS classifications. Moreover, about 60% of the AMCs were classified as high-solubility compounds (Class I and Class III), suggesting an important role for an in vitro dissolution test in setting quality control standards ensuring consistent biopharmaceutical quality for the commercially available CHM products. That is, provisionally, more than half of the AMCs of the top-selling CHMs included in this study would be candidates for a bioequivalence (BE) biowaiver, based on WHO recommendations and EMEA guidelines. Thus a dissolution requirement on these AMCs would represent a significant advance in the pharmaceutical quality of CHM today.

Quantitative assessment of traditional Oriental herbal formulation Samhwangsasim-tang using UPLC technique

A specific and reliable ultra-performance liquid chromatography-diode array detection method has been developed and validated for the quantitative assessment of a traditional Oriental herbal formulation, Samhwangsasim-tang (SST). A Halo reversed-phase amide column (2.7 µm, 4.6 × 150 mm) was used to separate marker compounds; detection was conducted by ultraviolet absorbance at 250 nm. The column temperature was maintained at 45°C. A mobile phase consisting of acetonitrile (A) and 0.1% trifluoroacetic acid in water (B) was found to be suitable for the separation, at a flow rate of 1.8 mL/min with gradient elution. Linearity, specificity, precision and recovery were calculated to validate the method and instrumentation. Under the described conditions, all marker compounds (rhaponticin, berberine, palmatine, baicalin, baicalein and wogonin) were collected within 25 min. All calibration curves of components showed good linearity (correlation coefficient > 0.9996). The limit of detection and limit of quantification ranged from 0.08-3.05 and 0.23-8.12 µg/mL, respectively. The relative standard deviation (RSD) and repeatability values of intra-day and inter-day precision were less than 2.30, 2.99 and 1.82%, respectively. In the recovery test, the accuracy ranged from 97.56-103.30% with RSD values less than 2.63%. The developed method was simple, specific, sensitive, accurate, precise and reproducible for the quantification of the active chemical constituents of SST. The simultaneous analysis of the contents of marker compounds in different SST samples prepared by different extraction procedures and different commercial products was successfully evaluated.