细菌耐药背景下中药抗菌作用研究进展

自青霉素被发现以来,抗菌药物被广泛应用于临床中,为人类的健康生活做出了巨大的贡献,但也由此产生了日渐严重的细菌耐药问题。中药材在中国有着数千年的临床使用历史,至今未发现明显的耐药菌产生,其作用可见一斑。中药的开发利用对解决细菌耐药性问题有非常大的潜力。作者就耐药菌的现状及抗耐药菌中药复方、单味中药、中药单体的实验研究结果作一简要综述,以期为临床用药以及中药新药研发提供参考。     

中药药渣中固氮菌、解磷菌、解钾菌的筛选

目的从中药药渣中分离出固氮菌、解磷菌、解钾菌,为叶类药渣微生物堆肥奠定基础。方法初筛采用平板涂布法,复筛均采用摇瓶法,测定相应发酵液中氮、可溶性磷、可溶钾含有量,以获得3种菌。结果从中药药渣中筛选出1株固氮菌(GD⁃1)、2株解磷菌(JP⁃1、JP⁃2)、3株解钾菌(JK⁃1、JK⁃2、JK⁃3),相应固氮、解磷、解钾能力分别为4.91、2.68、4.60、0.80、0.92、0.90 mg/L。结论来源于药渣中的菌株具有一定固氮、解磷、解钾能力,可适应粗糙的环境,将其按合适的配比施加于中药药渣制备微生物肥料时具有可行性。     

油茶粕中药复合剂抗菌作用的研究

目的:研究油茶粕中药复合剂的抗菌作用。方法:抗真菌作用:采用琼脂斜面稀释法检测油茶粕中药复合剂和油茶粕对皮肤真菌感染常见病原菌(絮状表皮癣菌、红色毛癣菌、石膏样毛癣菌和白假丝酵母菌)的最小抑菌浓度(MIC)和最小杀菌浓度(MBC)。抗细菌作用:采用牛津杯法检测油茶粕中药复合剂和油茶粕对皮肤真菌感染后的继发细菌感染常见病原菌(金黄色葡萄球菌、表皮葡萄球菌、绿脓假单胞菌、变形杆菌和大肠埃希菌)的抑菌圈,同时采用试管稀释法检测其对以上各供试菌的MIC和MBC。结果:油茶粕中药复合剂对絮状表皮癣菌、红色毛癣菌和白假丝酵母菌的MIC(62.50 mg/m L)低于油茶粕的MIC(≥250 mg/m L),油茶粕中药复合剂对絮状表皮癣菌、红色毛癣菌和白假丝酵母菌的MBC(≤125 mg/m L)低于油茶粕的MBC(≥250 mg/m L)。油茶粕中药复合剂对金黄色葡萄球菌的抑菌圈(17.00±0.63)mm大于油茶粕抑菌圈(11.20±0.61)mm,油茶粕中药复合剂对金黄色葡萄球菌和变形杆菌的MIC值(250 mg/m L)均低于油茶粕(250 mg/m L)。结论:油茶粕中药复合剂对絮状表皮癣菌、红色毛癣菌和白假丝酵母菌的抗菌作用明显优于油茶粕;油茶粕中药复合剂对金黄色葡萄球菌和变形杆菌的抑菌与和杀菌作用优于油茶粕。     

中药对肺炎克雷伯菌的抗菌作用的研究进展

肺炎克雷伯菌,因其耐药谱广,耐药率高,其治疗问题已成为世界性难题。中药具有低耐药性、多作用靶位的广谱抗菌效果,因此进行中药治疗或与西药联合治疗是一种对抗多重耐药菌的新型手段。检索近年来中国知网、万方全文和Pubmed等数据库的文献,从肺炎克雷伯的耐药机制和中药抗肺炎克雷伯菌耐药性作用等研究成果,阐述中药复合制剂以及其有效成分在临床上用于治疗肺炎克雷伯菌引起的感染的疗效及作用机制。中药可以通过抑制β-内酰胺酶、对抗生物膜的形成、对抗内毒素的作用以及抑制外排泵等起到抗肺炎克雷伯菌作用。通过对中药的抗菌作用机制进行深入研究,有助于准确全面地评价药效,为今后抗生素的合理选择提供依据。     

基于“产丁酸菌——中药多糖”的中药药理研究进展

最新研究表明肠道菌群与中药药理紧密相关,微生态机制研究已成为中药药理研究的新方向。诸多的肠道菌群功能类群中,产丁酸菌是肠道菌群的一个重要功能类群,其能够发酵膳食纤维、碳水化合物、内源蛋白等产生代谢产物,其菌群的失调也与多种疾病的发生相关,因产丁酸菌的重要次级代谢产物是丁酸,而丁酸作为一种重要的短链脂肪酸,在维持肠道健康、调节免疫系统和炎症反应、调节能量代谢、影响细胞分化和凋亡上发挥着重要作用。中药多糖具有含量多、不易被宿主消化吸收但能够被肠道菌群分解利用的特点,可以作为细菌碳源,对包括产丁酸菌在内的肠道菌群进行调节,通过改善肠道菌群结构达到治疗疾病的目的。因此,基于"产丁酸菌——中药多糖"的中药药理研究,从肠道细菌的功能和从菌群碳源的多糖成分研究中药药理,是中药微生态机制研究的新领域,亟待加强。该文结合最新文献和自己中药微生态药理工作,综述了丁酸的作用、产丁酸菌利用中药多糖的分子机制、中药多糖与产丁酸菌关联性等方面的研究进展,探讨了产丁酸菌与中药多糖之间的联系,并对基于"产丁酸菌——中药多糖"的中药药理研究进行了展望,以期抛砖引玉,为基于"产丁酸菌——中药多糖"的中药药理研究进展提供参考。     

中药内生菌的研究进展

目的综述植物内生菌在中药领域的研究进展。方法查阅了近几年来相关的文献,并进行分析总结。结果中药内生菌中活性物质结构类型很多,几乎涵盖天然药物化学中所有的有效成分,如生物碱类、蒽醌类、黄酮类、苯丙素类、甾体及萜类、苷类、多肽类等等。结论中药内生菌资源丰富,应用前景广阔,是新药研发的宝贵资源。     

产丁酸菌调节肠道微生态及中药的干预作用研究进展

产丁酸菌是以丁酸为主要代谢产物的一类肠道细菌,其中绝大多数为厚壁菌门,产丁酸菌能够利用膳食中不易消化的碳水化合物合成丁酸,进而通过给肠上皮细胞供能、影响肠黏膜屏障、调整肠道菌群结构、调节宿主免疫等生物功能调节肠道微生态,维持肠道内环境,从而达到改善肥胖、高血压等多种疾病的作用。因此,对产丁酸菌及丁酸的靶向调控成为防治多种人体疾病的潜在重要方法。中药经口服后进入体内首先和胃肠道接触,其与寄生于肠道黏膜上的微生物之间的相互作用是无可避免的重要环节。中药能够调节肠道菌群已得到证实,且中药由于组分复杂、成分众多可以以多层次、多途径、多靶点的方式发挥干预作用。其对产丁酸菌的作用主要体现在中药进入肠道后可起到"益生元"作用,富集有益的产丁酸菌,且中药多糖可作为发酵底物促进丁酸的合成,进而实现对产丁酸菌及丁酸的有效调节。基于此,本文探索了产丁酸菌及丁酸与肠道微生态之间的联系,并综述近几年中药干预产丁酸菌调节肠道微生态的相关研究,以期为中医药防治疾病及药物研发提供新的研究思路。     

基于产丁酸菌组合研究参苓白术散多糖体外降解的微生态机制

目的：研究“拟杆菌/厚壁菌”与产丁酸菌组合对中药多糖体外降解机制。方法：以参苓白术散多糖为唯一碳源构建多糖培养基（PM）,脑心浸液培养基（BHI）为对照,通过连续取样测定产丁酸菌在PM、及不同菌（包括脆弱拟杆菌、多形拟杆菌、厚壁菌YT2等）的PM降解液中的生长曲线,评估多糖体外降解机制。结果：产丁酸菌在多形拟杆菌降解的PM降解液中生长最好,在PM中的生长最差;PM/BHI分别经多糖降解菌降解后,PM中的产丁酸菌菌群数量更高;丁酸浓度变化中,经厚壁菌YT2的PM降解液最高,PM中产丁酸浓度最低;经多糖降解菌降解的PM降解液>经多糖降解菌降解的BHI降解液。结论：“拟杆菌/厚壁菌”产丁酸菌组合有利于对中药多糖的降解利用和丁酸生产。     

铜绿假单胞菌致病机理及中药抗感染的研究现状

归纳总结铜绿假单胞菌的致病机理和中药抗感染的研究现状,为抗铜绿假单胞菌的研究提供参考。通过查阅、整理近十年关于关铜绿假单胞菌的文献资料,从致病性的信号系统、致病机理、相关中药、所面临的问题以及未来的研究方向等方面进行总结和分析。结果显示铜绿假单胞菌通过释放毒性因子破坏宿主细胞的正常生理功能,甚至导致宿主细胞的死亡,同时信号系统是铜绿假单胞菌在机体内形成感染和难以清除极为重要的因素。中草药是天然药物中的精华,很多中药具有明显的抗细菌感染作用,且较少出现耐药性,可以为治疗铜绿假单胞菌感染提供新思路。     

铜绿假单胞菌生物膜形成机制及中药对其调控作用研究进展

铜绿假单胞菌是一种能引起机体急性或慢性感染的条件致病菌,极易形成生物膜是其产生耐药的一个重要因素。近年来研究表明,中药对铜绿假单胞菌生物膜形成具有明显的抑制作用。作者就铜绿假单胞菌生物膜形成周期、生物膜形成的主要调控信号系统以及中药对生物膜形成的影响进行综述。     

Antiplasmodial activity of extracts from seven medicinal plants used in malaria treatment in Cameroon

Aim of the study

In a search for new plant-derived biologically active compounds against malaria parasites, we have carried out an ethnopharmacological study to evaluate the susceptibility of cultured Plasmodium falciparum to extracts and fractions from seven Cameroonian medicinal plants used in malaria treatment. We have also explored the inhibition of the Plasmodium falciparum cysteine protease Falcipain-2.

Materials and methods

Plant materials were extracted by maceration in organic solvents, and subsequently partitioned or fractionated to afford test fractions. The susceptibility of erythrocytes and the W2 strain of Plasmodium falciparum to plant extracts was evaluated in culture. In addition, the ability of annonaceous extracts to inhibit recombinant cysteine protease Falcipain-2 was also assessed.

Results and discussion

The extracts showed no toxicity against erythrocytes. The majority of plant extracts were highly active against Plasmodium falciparumin vitro, with IC₅₀ values lower than 5 μg/ml. Annonaceous extracts (acetogenin-rich fractions and interface precipitates) exhibited the highest potency. Some of these extracts exhibited modest inhibition of Falcipain-2.

Conclusion

These results support continued investigation of components of traditional medicines as potential new antimalarial agents.     

金银花类药用植物IspE和IspH基因克隆和生物信息学分析

目的:克隆金银花类药用植物4-二磷酸胞苷-2-C-甲基赤藓糖激酶(4-diphosphocytidyl-2-C-methyl-D-erythritol kinase,IspE)和4-羟基-3-甲基-2-邻苯基二磷酸还原酶(4-hydroxy-3-methylbut-2-enyl diphosphate reductase,IspH)基因,并对其基因序列、蛋白特性和转录活性进行分析、比较.方法:从忍冬Lonicera japonica转录组测序结果中分析获得了IspE,IspH基因.分别以忍冬、红白忍冬L.japonica var.chinensis、红腺忍冬L.hypoglauca和水忍冬L.dasystyla新鲜花蕾为材料,利用RT-PCR技术克隆获得了4种金银花类药用植物IspE和IspH基因的全长cDNA.运用生物信息学分析软件,预测编码蛋白的结构和功能,并通过RT-PCR检测IspE和IspH在忍冬、红白忍冬、红腺忍冬、水忍冬花蕾中的转录情况.结果:金银花类药用植物IspE基因含有1个完整的开放阅读框,长度为1 221 bp,编码406个氨基酸;IspH含有一个完整的开放阅读框,长度为1 380 bp,编码459个氨基酸.IspE和IspH均为非分泌蛋白,均定位于叶绿体中.RT-PCR分析结果表明在忍冬、红腺忍冬和水忍冬的花蕾中IspE,IspH基因的转录水平没有显著差异,但红白忍冬花蕾中IspE,IspH基因的转录水平均显著高于忍冬.结论:克隆获得忍冬、红白忍冬、红腺忍冬和水忍冬中IspE,IspH基因,并证实了其在不同金银花类药用植物中的表达,为进一步研究IspE,IspH基因对萜类化合物生物合成和花香气以及颜色的影响奠定了基础.     

Comparative “in vitro” evaluation of the antiresorptive activity residing in four Ayurvedic medicinal plants. Hemidesmus indicus emerges for its potential in the treatment of bone loss diseases

Ethnopharmacological relevance

Four Indian plants, traditionally used in Ayurvedic medicine: Asparagus racemosus Willd., Emblica officinalis Gaertn., Hemidesmus indicus R. Br., and Rubia cordifolia L. were selected on the basis of their ethnobotanical use and of scientific evidence that suggests a potential efficacy in the treatment of bone-loss diseases. The antiresorptive properties of the four plants have been investigated. The aim was to provide adequate evidence for the exploitation of natural compounds as alternative therapeutics for the treatment of diseases caused by increased osteoclast activity.

Materials and methods

Decoctions were prepared from dried plant material according to the traditional procedure and standardization by HPLC was performed using marker compounds for each species. Total polyphenols, flavonoids and radical scavenging activity of the decoctions were also determined. The bioactivity of the plant decoctions was evaluated in subsequent phases. (1) A cytotoxicity screening was performed on the mouse monocytic RAW 264.7 cell line to define the concentrations that could be utilized in the following step. (2) The antiresorptive properties of plant decoctions were compared with that of a “gold standard” drug (alendronate) by measuring osteoclastogenesis inhibition and osteoclast apoptosis. (3) The toxic effect on bone forming cells was excluded by evaluating the impact on the proliferation of osteogenic precursors (mesenchymal stem cells, MSC).

Results

All the decoctions inhibited osteoclastogenesis similarly to alendronate at the highest doses, but Hemidesmus indicus and Rubia cordifolia were also effective at lower concentrations. Apoptosis increased significantly when cells were exposed to the highest concentration of Emblica officinalis, Hemidesmus indicus, and Rubia cordifolia. All concentrations of Emblica officinalis tested inhibited the proliferation of osteogenic precursors, while only the highest doses of Asparagus racemosus and Rubia cordifolia were toxic. On the contrary, Hemidesmus indicus did not affect osteogenic precursor growth at any concentration tested.

Conclusion

Among the medicinal plants included in the study, Hemidesmus indicus showed the greatest antiosteoclastic activity without toxic effect on osteogenic precursors. Therefore, Hemidesmus indicus exhibits the properties of an antiresorptive drug and represents the ideal candidate for further clinical investigations.     

中国石斛属植物文献计量研究

石斛是珍稀濒危中药材,目前正处于快速发展阶段。为全面了解我国石斛属植物研究的历史和发展现状,作者以1954～2010年"中国知网中国学术期刊网络出版总库"收录的石斛研究文献为依据,采用文献计量学的原理和方法,对我国石斛属植物研究文献从文献年代分布、期刊分布与被引频率、主题分布、研究对象分布、作者与研究机构分布等方面进行了统计与分析。结果表明,我国石斛研究明显分为起步(2个)、停滞、平稳发展、快速上升5个阶段;期刊分布存在离散性与集中性并存的现象,已形成核心期刊研究群,并以《中国中药杂志》、《中草药》和《陕西中医》为代表;研究主题广泛涉及临床与药理、组织培养与种苗繁育、成分分析等多个领域,已经形成比较稳定的研究机构和团队,但研究对象差异显著,以铁皮石斛、金钗石斛和霍山石斛最为集中。我国石斛属植物的研究已取得显著成果,但种植产业发展缓慢,供需矛盾突出,预计种苗繁育与人工种植、产品开发、化学与药理等方面是未来的研究热点,其文献报道仍将进一步上升。     

Effect of feeding Mucuna pruriens on helminth parasite infestation in lambs

Ethnopharmacological relevance

Mucuna pruriens is a tropical legume anecdotally reputed to have anthelmintic properties. This study was conducted to examine the validity of such claims.

Aim of the study

The aim of this study was to determine if ingestion of Mucuna seeds reduces helminth parasite infestation in lambs.

Materials and methods

Thirty-six Dorper × Katahdin ram lambs were assigned to three treatments, a cottonseed meal based control diet, a diet in which Mucuna replaced cottonseed meal and the control diet with levamisole (7.5 mg/kg body weight) administration. All diets were isonitrogenous and isocaloric. The 12 lambs in each treatment were assigned randomly to 4 pens, each containing 3 lambs. Lambs were trickle infected three times per week by gavage with infectious Haemonchus contortus larvae (2000 larvae/lamb) for 3 weeks.

Results

Levamisole treatment decreased fecal egg counts by 87% and abomasal worm counts by 83%. Mucuna intake did not statistically affect fecal egg counts or abomasal worm counts, though numerical (P > 0.10) reductions of 7.4% and 18.1%, respectively were evident. Anemia indicators, feed intake, and lamb growth were unaffected by treatment.

Conclusions

Levamisole reduced the Haemonchus parasite burden in lambs significantly but feeding Mucuna reduced the burden by levels unlikely to eliminate the clinical effects of parasitism.     

Antifungal activity of Brazilian medicinal plants involved in popular treatment of mycoses

A survey of medicinal plants used to treat common mycoses was done in the Curituba district, Sergipe State, Brazil. One hundred inhabitants were interviewed by health agents and traditional healers. Four different plants were the most cited (more than 50% of the citations): Ziziphus joazeiro, Caesalpinia pyramidalis, Bumelia sartorum and Hymenea courbaril. The aqueous extracts obtained following traditional methods and using different parts of these plants, were submitted to drop agar diffusion tests for primary antimicrobial screening. Only the water infusion extract of Ziziphus joazeiro and Caesalpinea pyramidalis presented a significant antifungal activity against Trichophyton rubrum, Candida guilliermondii, Candida albicans, Cryptococcus neoformans and Fonsecaea pedrosoi, when compared to the antifungal agent amphotericin B. The minimal inhibitory concentration (MIC) of the bioactive extracts was evaluated by the microdilution method. Best activity with a MIC of 6.5 microg/ml for both extracts was observed against Trichophyton rubrum and Candida guilliermondii. Ziziphus joazeiro and Caesalpinea pyramidalis extracts presented also low acute toxicity in murine models. The present study validates the folk use of these plant extracts and indicates that they can be effective potential candidates for the development of new strategies to treat fungal infections.     

α-Glucosidase inhibitory activity of selected Philippine plants

Ethnopharmacological relevance

Antidesma bunius Spreng. (Phyllantaceae), Averrhoa bilimbi L. (Oxalidaceae), Biophytum sensitivum (L.) DC. (Oxalidaceae), Ceriops tagal (Perr.) C.B. Rob. (Rhizophoraceae), Kyllinga monocephala Rottb. (Cyperaceae), and Rhizophora mucronata Lam. (Rhizophoraceae) are used as remedies to control diabetes. In the present study, these plants were screened for their potential α-glucosidase inhibitory activity.

Materials and methods

The 80% aqueous ethanolic extracts were screened for their α-glucosidase enzyme inhibitory activity using yeast alpha glucosidase enzyme.

Results

Except for A. bilimbi with IC₅₀ at 519.86±3.07, all manifested a significant enzyme inhibitory activity. R. mucronata manifested the highest activity with IC₅₀ at 0.08±1.82 μg mL⁻¹, followed by C. tagal with IC₅₀ at 0.85±1.46 μg mL⁻¹ and B. sensitivum with IC₅₀ at 2.24±1.58 μg mL⁻¹.

Conclusion

This is the first report on the α-glucosidase inhibitory effect of the six Philippine plants; thus, partly defining the mechanism on why these medicinal plants possess antidiabetic properties.     

European medicinal polypores – A modern view on traditional uses

Ethnopharmacological relevance

In particular five polypore species, i.e. Laetiporus sulphureus, Fomes fomentarius, Fomitopsis pinicola, Piptoporus betulinus, and Laricifomes officinalis, have been widely used in central European folk medicines for the treatment of various diseases, e.g. dysmenorrhoea, haemorrhoids, bladder disorders, pyretic diseases, treatment of coughs, cancer, and rheumatism. Prehistoric artefacts going back to over 5000 years underline the long tradition of using polypores for various applications ranging from food or tinder material to medicinal–spiritual uses as witnessed by two polypore species found among items of Ötzi, the Iceman. The present paper reviews the traditional uses, phytochemistry, and biological activity of the five mentioned polypores.

Materials and methods

All available information on the selected polypore taxa used in traditional folk medicine was collected through evaluation of literature in libraries and searches in online databases using SciFinder and Web of Knowledge.

Results

Mycochemical studies report the presence of many primary (e.g. polysaccharides) and secondary metabolites (e.g. triterpenes). Crude extracts and isolated compounds show a wide spectrum of biological properties, such as anti-inflammatory, cytotoxic, and antimicrobial activities.

Conclusions

The investigated polypores possess a longstanding ethnomycological tradition in Europe. Here, we compile biological results which highlight their therapeutic value. Moreover, this work provides a solid base for further investigations on a molecular level, both compound- and target-wise.     

In vitro and in vivo antimalarial and cytotoxic activity of five plants used in congolese traditional medicine

Aim of the study

The in vitro antiplasmodial activity and cytotoxicity of methanolic and dichloromethane extracts from five Congolese plants were evaluated. The plants were selected following an ethnobotanical survey conducted in D.R. Congo and focusing on plants used traditionally to treat malaria. The in vivo antimalarial activity of aqueous and methanolic extracts active in vitro was also determined in mice infected by Plasmodium berghei berghei.

Materials and methods

The growth inhibition of Plasmodium falciparum strains was evaluated using the measurement of lactate dehydrogenase activity. The extracts (aqueous, CH₃OH, EtOH and CH₂Cl₂) were prepared by maceration and tested in vitro against the 3D7 (chloroquine sensitive) and W2 (chloroquine resistant) strains of Plasmodium falciparum and against the human normal fetal lung fibroblasts WI-38 to determine the selectivity index. Some extracts were also used at the dose of 300 mg/kg to evaluate their activity in mice infected since 4 days by Plasmodium berghei.

Results

Two plants presented a very high activity (IC₅₀ < 3 μg/ml). These plants were Strychnos icaja roots bark (MeOH and CH₂Cl₂) and Physalis angulata leaves (MeOH and CH₂Cl₂). One plant (Anisopappus chinensis whole plant, MeOH and CH₂Cl₂) presented a high activity (IC50 < 15 μg/ml). The extracts of Anisopappus chinensis and Physalis angulata showed also a good inhibition of parasitemia in vivo. Flavonoids, phenolic acids and terpenes were identified in these plants by a general phytochemical screening method.

Conclusion

Three plants showed a very interesting antiplasmodial activity (Anisopappus chinensis, Physalis angulata and Strychnos icaja) and one of them showed a good selectivity index (>10, Anisopappus chinensis). Anisopappus chinensis and Physalis angulata were also active in vivo.     

Evaluation of the wound healing effect of some Jordanian traditional medicinal plants formulated in Pluronic F127 using mice (Mus musculus)

The wound healing effect of the aqueous extracts of Inula viscosa, Ajuga chia, Rubia taenifolia and Parieteria diffusa, and the oil of Laurus nobilis, dispersed in water, were examined. The 10% (w/w) Pluronic F127 (PF127) was added to the applied preparations, in order to modify the aqueous extracts viscosity, and to stabilize the oil dispersion. A full thickness wound was made in the dorsal area of the mice. The wounds were treated with the different preparations with 12h intervals for four times in two successive days. For 16 days, the wounds were visually observed, photographically documented and the wound area was measured. After day 16, the animals were sacrificed and the histology of the wound area was examined. The best wound healing activity was observed with the extract of Inula viscosa, followed by Parieteria diffusa, Laurus nobilis, Ajuga chia and the least active extract was that of Rubia taenifolia.