Anti-acetylcholinesterase activities of traditional Chinese medicine for treating Alzheimer's disease

Alzheimer's disease (AD) is a neurodegenerative disease characterized by progressive memory loss and cognitive impairment. It is the most common type of dementia in the ageing population due to a severe loss of cholinergic neurons in selected brain area. At present, acetylcholinesterase inhibitors (AChEI) are the first group of drugs approved by the FDA to treat mild to moderate Alzheimer's disease. Most of these drugs such as huperzine and galanthamine are originally isolated from plants. In this study, the AChE inhibitory activities from extracts of Chinese medicinal herbs that have traditionally been prescribed to treat insomnia and brain function disorders were examined in a 96-well plate assay based on Ellman's method. Both ethanol and aqueous extracts of 26 traditional Chinese medicinal herbs were tested. Inhibitory effects were expressed as the percentage of inhibition. For the herbal extracts that were shown to exert a significant inhibition, dose-dependent inhibitory assays were also performed. Ethanol and aqueous extracts of six herbs were found to have high AChE inhibitory activities in a dose-dependent manner. The IC(50) of these herbal extracts on inhibition of AChE are at around 5-85mum/ml. The results of this study indicate that there is a great potential to search for novel usage of these medicinal herbs for the treatment of AD.     

Melatonin in Chinese medicinal herbs

Melatonin is a highly conserved molecule that not only exists in animals, but also is present in bacteria, unicellular organisms and in plants. Since melatonin is an antioxidant, in plants melatonin was speculated to protect them from intrinsic and environmental oxidative stress. More importantly, melatonin in edible plants inevitably enters animals and human through feed and food. In this study, more than 100 Chinese medicinal herbs were analyzed using the methods of solid phase extraction and HPLC-FD on-line with MS to determine whether melatonin is present in these commonly used herbs. Melatonin was detected in majority of these plants. Sixty-four of them contain melatonin in excess of 10 ng per gram dry mass. Melatonin levels in several herbs are in excess of 1000 ng/g. It is well known that normal average physiological plasma levels of melatonin are only 10-60 pg/mL. These high level-melatonin containing plants are traditionally used to treat diseases which presumably involve free radical damage. The current study provides new information concerning one potentially effective constituent present in a large number of medicinal herbs. The results suggest that these herbs should be reevaluated in reference to their nutritional and medicinal value.     

Correlation between the different therapeutic properties of Chinese medicinal herbs and delayed luminescence

In the practice and principle of Chinese medicine, herbal materials are classified according to their therapeutic properties. ‘Cold’ and ‘heat’ are the most important classes of Chinese medicinal herbs according to the theory of traditional Chinese medicine (TCM). In this work, delayed luminescence (DL) was measured for different samples of Chinese medicinal herbs using a sensitive photon multiplier detection system. A comparison of DL parameters, including mean intensity and statistic entropy, was undertaken to discriminate between the ‘cold’ and ‘heat’ properties of Chinese medicinal herbs. The results suggest that there are significant differences in mean intensity and statistic entropy and using this method combined with statistical analysis may provide novel parameters for the characterization of Chinese medicinal herbs in relation to their energetic properties. Copyright © 2015 John Wiley & Sons, Ltd.     

Mineral content of Chinese medicinal herbs used as diuretic treatments for Taiwanese children

Eighteen major, minor and trace elements in 12 Chinese medicinal herbs commonly consumed by Taiwanese Children as diuretics were determined by instrumental neutron activation analysis (INAA). Dried and powdered herb samples were irradiated in a neutron flux of ca. 2 x 10(12) n/cm2 s under separate short and long irradiation schemes. Lichen (IAEA-336) was used as the reference standard, and tomato leaves (NIST-SRM 1570a) were employed for cross-checking the accuracy of the results. INAA was shown to be a reliable multi-element analytical method for determining the content of both toxicologically and nutritionally important minerals in Chinese medicinal herbs. Determined elements were present in the dried herbs in concentrations ranging from 10(4) to 10(-3) microg/g. The mineral contents and the maximum daily intake values of the tested herbs were compared with published values and with the recommended daily intakes for Taiwanese children as specified by the World Health Organization.     

Simultaneous determination of 76As, 122Sb and 153Sm in Chinese medicinal herbs by epithermal neutron activation analysis

Optimal conditions for the simultaneous determination of As, Sb and Sm in Chinese medicinal herbs using epithermal neutron activation analysis were investigated. The minimum detectable concentrations of 76As, 122Sb and 153Sm in lichen and medicinal herbs depended on the weight of the irradiated sample, and irradiation and decay durations. Optimal conditions were obtained by wrapping the irradiated target with 3.2 mm borated polyethylene neutron filters, which were adopted to screen the original reactor fission neutrons and to reduce the background activities of 38Cl, 24Na and 42K. Twelve medicinal herbs, commonly consumed by Taiwanese children as a diuretic treatment, were analysed since trace elements, such as As and Sb, in these herbs may be toxic when consumed in sufficiently large quantities over a long period. Various amounts of medicinal herbs, standardised powder, lichen and tomato leaves were weighed, packed into polyethylene bags, irradiated and counted under different conditions. The results indicated that about 350 mg of lichen irradiated for 24 h and counted for 20 min following a 30-60 h decay period was optimal for irradiation in a 10(11)n/cm s epithermal neutron flux. The implications of the content of the studied elements in Chinese medicinal herbs are discussed.     

Antioxidant activity and phenolic compounds of 112 traditional Chinese medicinal plants associated with anticancer

Cancer prevention and treatment using traditional Chinese medicines have attracted increasing interest. This study characterizes antioxidant activity and phenolic compounds of traditional Chinese medicinal plants associated with anticancer, comprising 112 species from 50 plant families. The improved ABTS(*+) method was used to systematically assess the total antioxidant capacity (Trolox equivalent antioxidant capacity, TEAC) of the medicinal extracts. The TEAC values and total phenolic content for methanolic extracts of herbs ranged from 46.7 to 17,323 micromol Trolox equivalent/100 g dry weight (DW), and from 0.22 to 50.3 g of gallic acid equivalent/100 g DW, respectively. A positive, significant linear relationship between antioxidant activity and total phenolic content (all R(2) values>/=0.95) showed that phenolic compounds were the dominant antioxidant components in the tested medicinal herbs. Major types of phenolic compounds from most of the tested herbs were preliminarily identified and analyzed, and mainly included phenolic acids, flavonoids, tannins, coumarins, lignans, quinones, stilbenes, and curcuminoids. These medicinal herbs exhibited far stronger antioxidant activity and contained significantly higher levels of phenolics than common vegetables and fruits. Traditional Chinese medicinal plants associated with anticancer might be potential sources of potent natural antioxidants and beneficial chemopreventive agents.     

Analysis of urinary aristolactams by on-line solid-phase extraction coupled with liquid chromatography-tandem mass spectrometry

Aristolochic acids (AAs), nephrotoxicants and known human carcinogens, are a mixture of structurally related derivatives of nitrophenanthrene carboxylic acids with the major components being aristolochic acid I and aristolochic acid II. People may ingest small amounts of AAs from its natural presence in medicinal plants and herbs of the family Aristolochiaceae, including the genera Aristolochia and Asarum, which have been used worldwide in folk medicine for centuries. In order to assess AA intake, an on-line solid-phase extraction coupled with liquid chromatography-tandem mass spectrometry (on-line SPE-LC/MS/MS) method was developed to analyze their most abundant corresponding metabolites, aristolactams (ALs), in urine to serve as biomarkers. The limits of quantitation were 0.006 ng for aristolactam I (AL-I), and 0.024 ng for aristolactam II (AL-II) on column. Recovery varied from 98.0% to 99.5%, and matrix effects were within 75.3-75.4%. This method was applied to analyze ALs in the urine samples collected on days 1, 2, 4, and 7 from mice treated with 30 mg/kg or 50mg/kg AAs. Their half lives were estimated to be 3.55 h and 4.00 for AL-I, and 4.04 and 4.83 h for AL-II, depending on AAs doses. These results demonstrated that the first simple on-line SPE-LC/MS/MS method was successfully developed to analyze urinary ALs with excellent sensitivity and specificity to serve as biomarkers to assess current AA intake from AAs-containing Chinese herbs.     

四种中草药成分对醛糖还原醇和脂类过氧化的抑制作用

我们在体外研究了四种中草药提取物对醛糖还原酶及脂类过氧化的抑制作用。结果表明,四种中草药的提取物在不同浓度下,对醛糖还原酶活性及脂类过氧化作用均有不同程度的抑制作用,其抑制醛糖还原酶活性的作用属非竞争性抑制类型。对醛糖还原酶活性及脂类过氧化的抑制作用均随中草药提取物浓度的降低而降低。本实验的结果证明中草药中含有抗脂类过氧化及抑制醛糖还原酶的某些成分。     

Monoclonal antibodies against neoantigens of the terminal C5b-9 complex of human complement

Assembly of the terminal C5b-C9 complement components into the cytolytic C5b-9 complex is accompanied by exposure of characteristic neoantigens on the macromolecule. We report the production and characterization of mouse monoclonal antibodies to C9-dependent neoantigens of human C5b-9. Binding-inhibition assays with EDTA-human plasma and micro-ELISA assays with purified C9 showed that the antibodies did not react with native complement components and thus confirmed the specificity of the antibodies for the neoantigens. The monoclonal antibodies did, however, cross-react with cytolyticaIly inactive, fluid-phase C5b-9 complexes, Thus, expression of the neoantigenic determinants was not dependent on the formation of high molecular weight C9 polymers with the complex, since these are absent in fluid-phase C5b-9. Radioiodinated antibodies could be utilized in immunoradiometric assays for the detection and quantitation of C5b-9 on cell membranes. Cross-reactivities of the antibodies with C9-dependent neoantigens of several other animal species were examined and antibody clones cross-reacting with rabbit (clones 3BI, 3Dg, and 2F3), sheep (clones 3Dg and 2F3) and guinea-pig (clone 3D8) neoantigens were identified . Three of four tested clones (3D8, 2F3, IA12) precipitated C5b-9 complexes in double-diffusion assays, probably due to their interaction with multiple and repeating C9-epitopes on the terminal complexes. The monoclonal antibodies will be of value for definitive identification and quantitation of C5b-9 on cell membranes and in tissues, and for establishing immunoassays for detection and quantitation of terminal fluid-phase C5b-9 complexes in plasma.     

Development of response surface methodology for optimization of parameters and quantitative analysis of chebulinic acid from composition of medicinal herbs by HPLC

The purpose of the research is to study the development of response surface methodology for optimization of chebulinic acid extraction from composition of medicinal herbs such as Terminalia chebula, Phyllanthus emblica and seeds of Dimocarpus longan. Optimization of extraction parameters such as weight dosages, pH and time were carried out by response surface methodology (RSM). The optimal conditions determined for extraction of chebulinic acid through response surface methodology were dosage (6.25 g), pH (5.7) and time (24.23 h). These results showed that the developed model is satisfactory and relevant for the extraction of chebulinic acid. The analysis of variance showed a high goodness of model fit and the performance of the RSM method for improving chebulinic acid extraction from the composition of medicinal herbs. Quantitative estimation of chebulinic acid in the composition of medicinal herbs by HPLC studies revealed that 0.712% w/w of chebulinic acid content was present in the composition of herbal powder.     

Residues and contaminants in medicinal herbs—A review

With the increasing popularity and use of medicinal herbs, their global demand has gained momentum. Developing countries, including China, India and South East Asian (SEA) countries, are the centres of origin and major global suppliers for most of these traditionally used medicinal herbs. One of the factors affecting the quality of these herbs is the contamination of heavy metals, mycotoxins, pesticide residues, polycyclic aromatic hydrocarbons (PAHs) and fumigants. These contaminants can accumulate during the cultivation, storage and processing of herbs and may have adverse effects on consumer health. There have been various reports regarding the presence of these contaminants in medicinal herbs. This review discusses the important contaminants of medicinal herbs, the frequency and magnitude of their occurrences, the potential causes of contamination and their regulatory limits in medicinal herbs. The major challenge in the international trade of medicinal herbs is the lack of common guidelines, regulatory measures and monitoring body to strictly enforce their regulation.     

Simultaneous determination of theophylline and its major metabolites in urine by reversed-phase ion-pair high-performance liquid chromatography

A new, highly selective high-performance liquid-chromatographic (HPLC) assay for theophylline and its major metabolites in urine is described. The method utilizes an ion-pair extraction followed by separation and quantitation by reversed-phase ion-pair gradient-elution HPLC. Comparison with several other methods showed that interferences were present in too many blank urine samples to allow for the accurate quantitation of the metabolites of theophylline by direct injection-isocratic HPLC assays. Sample processing involving ion-pair complexing and extraction together with gradient-elution systems is recommended for accurate pharmacokinetic studies.     

Inhibition of acetylcholinesterase by extracts and constituents from Angelica archangelica and Geranium sylvaticum

The aim of this study was to explore the acetylcholinesterase (AChE) inhibition of several Icelandic medicinal herbs. Ethanolic extracts of Angelica archangelica seeds and the aerial parts of Geranium sylvaticum proved effective, with IC50 values of 2.20 mg/ml and 3.56 mg/ml, respectively. The activity of imperatorin and xanthotoxin from A. archangelica was measured. Xanthotoxin proved much more potent than imperatorin, with an IC50 value of 155 microg/ml (0.72 mM) but that for imperatorin was above 274 microg/ml (1.01 mM). However, furanocoumarins seem to have a minor part in the total activity of this extract. Synergistic interaction was observed between the extracts of A. archangelica and G. sylvaticum. Several medicinal herbs (Achillea millefolium, Filipendula ulmaria, Thymus praecox and Matricaria maritima) did not show AChE inhibitory activity.     

酶法辅助强化中药提取过程研究进展

利用酶法强化中药提取已成为中药开发的重要手段,酶法提取因其反应特异性强、高效、条件温和、易于控制等优点而具有广阔的应用前景。介绍了应用于中药材提取过程中的酶法辅助技术,归纳了酶法在中药材重要活性成分提取、中药提取液的澄清纯化中的应用,分析了酶法辅助提取对中药活性组成的影响,提出了酶法与超声技术的结合应用方法。     

Chinese medicinal herbs modulate mutagenesis, DNA binding and metabolism of aflatoxin B1.

Oldenlandia diffusa (OD) and Scutellaria barbata (SB) have been used in traditional Chinese medicine for treating liver, lung and rectal tumors while Astragalus membranaceus (AM) and Ligustrum lucidum (LL) are often used as an adjunct in cancer therapy. In this study, we determined the effects of aqueous extracts of these four herbs on aflatoxin B1 (AFB1)-induced mutagenesis using Salmonella typhimurium TA100 as the bacterial tester strain and rat liver 9000 x g supernatant as the activation system. The effects of these herbs on [3H]AFB1 binding to calf-thymus DNA were assessed. Organosoluble and water-soluble metabolites of AFB1 were extracted and analyzed by high-performance liquid chromatography (HPLC). Mutagenesis assays revealed that all of these herbs produced a concentration-dependent inhibition of histidine-independent revertant (His+) colonies induced by AFB1. At a concentration of 1.5 mg/plate, SB and OD in combination exhibited an additive effect. The trend of inhibition of these four herbs on AFB1-induced mutagenesis was: SB greater than LL greater than AM. LL, OD and SB significantly inhibited AFB1 binding to DNA, reduced AFB1-DNA adduct formation, and also significantly decreased the formation of organosoluble metabolites of AFB1. Our data suggest that these Chinese medicinal herbs possess cancer chemopreventive properties.     

A new colorimetric DPPH• scavenging activity method with no need for a spectrophotometer applied on synthetic and natural antioxidants and medicinal herbs

2,2-Diphenyl-1-picrylhydrazyl (DPPH^?) radical scavenging, the most commonly used antioxidant method with more than seventeen thousand articles cited, is very practical; however, as with most assays, it has the major disadvantage of dependence on a spectrophotometer. To overcome this drawback, the colorimetric determination of the antioxidant activity using a scanner and freely available Image J software was developed. In this new method, the mixtures of solutions of DPPH^? and standard antioxidants or extracts of common medicinal herbs were dropped onto TLC plates, after an incubation period. The spot images were evaluated with Image J software to determine CSC₅₀ values, the sample concentrations providing 50% colour reduction, which were very similar with the SC₅₀ values obtained with spectrophotometric method. The advantages of the new method are the use of lower amounts of reagents and solvents, no need for costly spectrophotometers, and thus significantly lowered costs, and convenient implementation in any environment and situation.     

Assessment of toxigenic fungi on Argentinean medicinal herbs

This work was performed to determine the incidence of toxigenic fungi and their mycotoxins on 152 dried medicinal and aromatic herbs, belonging to 56 species, which are used as raw material for drugs. International methodologies for fungal enumeration and identification were applied as well as TLC and HPLC techniques for toxins detection. The 52% out of 152 samples were contaminated with species from Aspergillus genus, 27% belonging to the Flavi section and 25% to the Circumdati section. The 16% of the total samples was contaminated with species from Fusarium genus. Aspergillus flavus and A. parasiticus (Flavi section), were the predominant species isolated, 50% out of 40 isolates were toxigenic. Aflatoxin concentrations ranged from 10 to 2000 ng/g. Only 26% of isolates from the Circumdati section (A. alliaceus, A. ochraceus and A. sclerotiorum) produced ochratoxin A in low concentrations between 0.12 and 9 ng/g. From a total of 29 strains of Fusarium spp., 27.5% were Fusarium verticillioides and F. proliferatum, which produced fumonisin Bland fumonisin B2 ranged from 20 to 22000 microg/g and from 5 to 3000 microg/g respectively. The remaining species, F. equiseti, F. oxysporum, F. semitectum, F. compactum, F. sombucinum and F. solani were able to produce neither group A and B trichothecenes nor zearalenone. The incidence of A. ochraceus and Fusarium spp. and their toxigenic capacities on medicinal herbs were studied for the first time in Argentina. It would be important to look for natural contamination to define acceptability Limits which allow the control of sanitary quality of medicinal herbs used as phytotherapic medicines in several countries.     

A sensitive chromatographic method for the detection of pyruvyl groups in microbial polymers from sediments

A method was developed for the quantitation of pyruvyl groups in microbial polymers using mild acid hydrolysis, o-phenylenediamine labeling, reversed-phase high-performance liquid chromatography (RP-HPLC), and fluorescence detection. The method was used to determine the pyruvate content of various microbial exopolysaccharides and to estimate the abundance of polymeric pyruvate in freshwater sediments. The results of this method were compared with those of several other pyruvate assays. The detection limit of the method was 1.6 nmol pyruvate. As little as 3.7g of the bacterial polysaccharide xanthan gum, or from 5 to 22 mg of sediment (depending on polymeric pyruvate content), were needed for detection and quantitation of polymeric pyruvate. The results should be useful in determining the contribution of polymeric pyruvate to total metal-binding ligands in sediments.     

江苏宝华山区药用维管植物资源组成分析

为全面了解江苏宝华山区药用维管植物资源现状,依据“第四次全国中药资源普查”项目的要求,采用线路调查和样方调查相结合的方法,对该区域药用维管植物的种类组成、科属构成、生活型、濒危现状和中药学特征以及重点药用维管植物的资源状况进行了调查和分析。结果显示：宝华山区共有药用维管植物164科620属1089种(含种下等级),分别占江苏省药用维管植物科、属、种数的88.2%、87.3%、81.0%,其中,蕨类植物25科33属50种、裸子植物7科13属16种、被子植物132科574属1023种;在科属构成上均以包含单种和寡种的小科、小属为主。从该区域药用维管植物的生活型看,以草本最为丰富,有734种;乔木和灌木(含木质藤本)较少,分别有125和230种。从所在的植被类型看,阔叶林数量最多,其后依次为针阔混交林、灌草丛、人工植被,针叶林数量最少。从地理分布看,与同区域种子植物的地理分布特征基本吻合,具有亚热带向温带过渡的特点。从珍稀濒危状况看,该区域现存中国特有属14属、国家级珍稀濒危药用维管植物18种、江苏省省级保护药用维管植物32种。从中药材上看,有道地药材17种和重点药用维管植物130种,但各种类的数量总体上较少。从该区域药用维管植物的中药学特征看,在药用部位上以全草(株)类、根和根茎类较多,分别占总种数的44.2%和24.0%;在药性上以平性最多,占30.9%;在药味上以苦味最多,占40.0%;有毒的药用植物占12.9%,其中小毒种类最多。综合分析结果显示：宝华山区药用维管植物种类丰富,其中,道地药材占有一定比例,但重点药用维管植物数量有限且分布频度总体较低。根据上述调查结果,对宝华山区药用维管植物资源的保护和利用提出了一些建议。