花刺参中三个新的三萜皂苷类化合物

目的 研究花刺参体内的活性皂苷类成分。方法 运用硅胶、Sephadex LH-20柱色谱等方法进行分离纯化,利用IR,¹H、¹³C NMR,MS等光谱技术鉴定其化学结构。结果 从花刺参中分离并鉴定出3个化合物,分别为3-O-[3-O-甲基-β-D-吡喃葡萄糖-（1→3）-β-D-吡喃木糖-（1→3）-β-D-吡喃葡萄糖-（1→2）-β-D-吡喃木糖]-海参烷-7,24-二烯-3β,23S-二醇,命名为variegatuside C;3-O-{3-O-甲基-β-D-吡喃葡萄糖-（1→3）-β-D-吡喃木糖-（1→4）-β-D-吡喃葡萄糖-（1→2）[β-D-吡喃葡萄糖-（1→4）]-β-D-吡喃木糖}-海参烷-8-烯-3β,23S-二醇,命名为variegatuside D;3-O-{3-O-甲基-β-D-吡喃葡萄糖-（1→3）-β-D-吡喃木糖-（1→4）-β-D-吡喃葡萄糖-（1→2）[3-O-甲基-β-D-吡喃葡萄糖-（1→3）-β-D-吡喃葡萄糖-（1→4）]-β-D-吡喃木糖}-海参烷-9-烯-3β,23S-二醇,命名为variegatuside E。结论 3个化合物均为新化合物。     

苦玄参中一个新葫芦苦素成分的分离与结构鉴定

目的研究苦玄参中的化学成分。方法用硅胶和MCI柱色谱分离纯化，通过光谱(IR，UV，MS，¹HNMR，¹³CNMR，DEPT，HMQC，¹H-¹H COSY和HMBC)鉴定其化学结构。结果得到2个葫芦苦素类化合物，分别鉴定为11,24-二酮-5,21-二烯葫芦苦素-3α-O-β-D-吡喃木糖基-16α-O-α-L-吡喃鼠李糖苷(脱氢拜俄尼苷，1)和己降葫芦苦素F(2)。结论化合物1为新化合物，化合物2为首次从苦玄参中分离得到。     

内蒙古香青兰总黄酮提取工艺优化及其抗氧化活性成分分析

目的 优化内蒙古香青兰总黄酮提取工艺,并对抗氧化活性成分进行分析。方法 采用单因素试验法结合响应面法优化提取工艺,并通过清除DPPH自由基试验、ABTS自由基清除试验、抑制羟基自由基试验和抑制超氧阴离子自由基试验筛选提取物的抗氧化活性成分,用高效液相色谱-电喷雾离子源-离子阱-飞行时间质谱联用技术(LC-MS-IT-TOF)对抗氧化活性成分进行分析。结果 内蒙古香青兰总黄酮最佳制备条件为提取温度67℃、乙醇体积百分数63%、料液比 1:58,提取物中总黄酮含量4.77%。香青兰总黄酮抗氧化活性成分为乙酸乙酯活性成分,主要包含迷迭香酸、迷迭香酸甲酯、木犀草素、芹菜素、芹菜素-7-O-b-D-葡萄糖苷等化学成分。结论 首次建立内蒙古香青兰总黄酮制备方法,该方法简单易操作,提取物总黄酮含量丰富,乙酸乙酯活性成分是香青兰总黄酮抗氧化活性成分,含有多种黄酮类化合物。     

紫茎泽兰中的萜类成分研究

目的 对紫茎泽兰中的萜类成分及其药理活性进行研究。方法 采用D101、HP20大孔树脂、硅胶柱色谱、葡聚糖凝胶色谱、高效液相色谱等多种分离分析手段，MS、¹H-NMR和¹³C-NMR等多种波谱技术以及ECD计算鉴定化合物结构，并采用MTT法对分离得到的单体化合物进行细胞毒活性的筛选。结果 从紫茎泽兰95%乙醇提取物的石油醚和乙酸乙酯萃取部位中分离得到10个化合物，分别鉴定为泽兰酮D (1)、thymoquinol 5-O-β-glucopyranoside (2)、thymoquinol2-O-β-glucopyranoside (3)、2R^*,3S^*-toxol-7-O-β-D-glucopyranoside (4)、6-甲氧基-山柰酚-7-O-β-D-葡萄糖苷(5)、万寿菊素-4’-甲氧基-7-O-β-D-葡萄糖苷(6)、6-hydroxykaempferol-7-O-β-D-glucopyranoside (7)、eupatonriochromene (8)、demethoxyencecalin (9)、encecalin (10)。化合物10对食管癌细胞的IC₅₀值为178.4 μmol·L^-1。结论 其中化合物1为新化合物，化合物6为首次从泽兰属中分离得到，化合物2，3，7为首次从紫茎泽兰中分离得到。化合物10对食管癌细胞Eca-109具有一定的细胞毒活性。     

桂花不同溶剂提取物对氧自由基清除作用的ESR研究

目的 研究桂花不同提取物对氧自由基的清除作用。方法 利用不同极性溶剂(水、石油醚、乙酸乙酯、正丁醇)浸提桂花粉后得到不同极性的提取物。通过电子自旋共振(ESR)和自旋捕集技术,以1,1-二苯基-2-三硝基苯肼自由基(DPPH)及核黄素光照条件下产生超氧阴离子O₂^-自由基体系,检测桂花中各组分清除DPPH自由基及O₂^-的能力。结果 以维生素C为对照,桂花水提取物、石油醚提取物、乙酸乙酯提取物、正丁醇提取物及维生素C清除DPPH自由基能力IC₅₀分别为59.63,53.93,28.33,38.89,40.93 μg·mL^-1;各提取物及维生素C对超氧阴离子O₂^-自由基清除能力IC50分别为63.37,55.47,30.20,48.36,41.52 μg·mL^-1。其中各提取物的乙酸乙酯提取物的DPPH及O₂^-清除率最大。结论 通过比较各组分对DPPH自由基及超氧阴离子自由基的清除能力,了解桂花中抗氧化成分在各相中的分布情况,并据此进行有目的的分离桂花中的抗氧化成分。     

百蕊草亲水性化学成分研究

目的 对百蕊草中亲水性化学成分进行研究。方法 采用硅胶柱色谱、SephadexLH-20凝胶柱色谱等分离手段,对百蕊草水提取物经AB-8大孔树脂吸附,50%乙醇洗脱的亲水性组分（TT50）进行分离纯化,应用核磁共振波谱分析、结合文献报道鉴定化合物结构。结果 从TT50中分离纯化得到6个化合物,分别鉴定为：山奈酚（1）,紫云英苷（2）,山奈酚-3,7-二-O-β-D-吡喃葡萄糖苷（3）,山奈酚-3-O-L-吡喃鼠李糖基（1→2）-β-D-吡喃葡萄糖苷（4）,山奈酚-3-O-L-吡喃鼠李糖基（1→2）-［6-O-乙酰基］-β-D-吡喃葡萄糖苷（5）,芸香苷（6）。结论 TT50中主要成分为以山奈酚为母核的黄酮苷类化合物,化合物4、5为首次从百蕊草中分离得到。     

滇白珠木脂素苷的研究

目的： 研究民间药滇白珠(Gaultheria yunnanensis (Franch.) Rehd.)的化学成分。方法： 用95%乙醇提取,硅胶柱色谱和聚酰胺柱色谱分离纯化,通过各种光谱分析鉴定其结构。结果： 从正丁醇萃取物中分离鉴定了4个木脂素苷类化合物。其结构分别鉴定为(-)-isolariciresinol-2a-O-β-D-xylopyranoside (D₁),(+)-lyoniresinol-2a-O-β-L-arabinopyranoside (D₂),(-)-5′-methoxyisolariciresinol-2a-O-β-D-xylopyranoside (D₃)和(+)-lyoniresinol-2a-O-β-D-glucopyranoside (D₄)。结论： 化合物D2为一新化合物,命名为滇白珠苷A(Gaultheroside A),D₁,D₃,D₄为首次从杜鹃花科植物中分得。     

苦碟子化学成分的分离与鉴定

目的对菊科苦荬菜属植物抱茎苦荬菜[Ixeris sonchifolia(Bge.)Hance]的化学成分进行研究。方法运用硅胶﹑聚酰胺柱色谱﹑Sephadex LH-20柱色谱﹑ODS柱色谱、制备HPLC等分离手段进行化学成分的分离纯化,根据理化性质及波谱数据鉴定其结构。结果从苦碟子全草中分离得到4个化合物。分别鉴定为3β-hydroxyolean-12-en-11-one acetate(1)、3,4-dihydroxybenzalacetone(2)、7-O-β-D-glucopyranosyl-luteolin-3'-O-β-D-glucopyranoside(3)、5,7-dihydroxy-4'-methoxy-fla-vone-7-rutinoside(4)。结论这些化合物均为首次从该属植物中分离得到。     

消乳散结胶囊联合他莫昔芬治疗乳腺增生症的疗效观察

目的 研究瑞香狼毒Stellera chamaejasme花中黄酮和木脂素类化学成分及其抗氧化活性,分析构效关系。方法 利用大孔吸附树脂、正反相硅胶、Sephadex LH-20等色谱分离材料,通过柱色谱和高效液相色谱等分离方法进行分离纯化,运用核磁共振（NMR）、质谱（MS）等波谱技术鉴定化合物结构,并采用FRAP法、DPPH法和ABTS法对分离得到的化合物进行体外抗氧化活性测试。结果 从瑞香狼毒花甲醇提取物中分离鉴定了12个化合物,分别鉴定为艾黄素（1）、槲皮素（2）、isoscutellarein-8-O-β-D-glucuronopyranoside（3）、槲皮素-3-O-β-D-葡萄糖苷（4）、紫云英苷（5）、hypolaetin-8-O-β-D-glucuronopyranoside（6）、kaempferol 3-O-β-D-glucopyranosyl-（1→2）-O-α-L-xylopyranoside（7）、rel-（3R,3''S,4R,4''S）-3,3'',4,4''-tetrahydro-6,6''-dimethoxy[3,3''-bi-2H-benzopyran]-4,4''-diol（8）、马台树脂醇（9）、乌拉尔醇（10）、环黄芪醇（11）、松脂醇（12）。抗氧化活性实验表明,黄酮和木脂素类化合物均显示了较强的抗氧化活性。结论 化合物1、3、5～7和10为首次从该植物中分离得到;化合物2、4、5和10表现出显著的抗氧化活性,其中黄酮类化合物C-3或C-8位连有糖链会降低其抗氧化活性。     

马尾松松针中木脂素类化学成分的研究

目的研究松科(Pinaceae)植物马尾松(P.massoniana Lamb.)松针(pine needles)水煎液中的化学成分。方法利用Diaion HP-20,Toyopearl HW-40和硅胶等柱色谱技术进行分离纯化,根据化合物的理化性质和光谱数据进行结构鉴定。结果从马尾松针水煎液镇痛作用较强的正丁醇萃取部位分离得到3个木脂素类化合物,其化学结构分别确定为化合物7(massonianoside D): (7S,8r)-4,9′-二羟基-3,3′-二甲氧基-7,8-二氢苯骈呋喃-1′-丙醇基新木脂素-9-O-α-L-鼠李糖苷;化合物8(异落叶松脂素):4,4′,9,9′-四羟基-3,3′-二甲氧基-7-苯基四氢萘木脂素;化合物9(异落叶松脂素-9-O-木糖苷):4,4′,9′-三羟基-3,3′-二甲氧基-7-苯基四氢萘木脂素-9-O-β-D-木糖苷。结论化合物7为新化合物,化合物8,9为首次从本植物中分离得到。     

Genetic regulation of the ramA locus and its expression in clinical isolates of Klebsiella pneumoniae

Tigecycline resistance has been attributed to ramA overexpression and subsequent acrA upregulation. The ramA locus, originally identified in Klebsiella pneumoniae, has homologues in Enterobacter and Salmonella spp. In this study, we identify in silico that the ramR binding site is also present in Citrobacter spp. and that Enterobacter, Citrobacter and Klebsiella spp. share key regulatory elements in the control of the romA-ramA locus. RACE (rapid amplification of cDNA ends) mapping indicated that there are two promoters from which romA-ramA expression can be regulated in K. pneumoniae. Correspondingly, electrophoretic binding studies clearly showed that purified RamA and RamR proteins bind to both of these promoters. Hence, there appear to be two RamR binding sites within the Klebsiella romA-ramA locus. Like MarA, RamA binds the promoter region, implying that it might be subject to autoregulation. We have identified changes within ramR in geographically distinct clinical isolates of K. pneumoniae. Intriguingly, levels of romA and ramA expression were not uniformly affected by changes within the ramR gene, thereby supporting the dual promoter finding. Furthermore, a subset of strains sustained no changes within the ramR gene but which still overexpressed the romA-ramA genes, strongly suggesting that a secondary regulator may control ramA expression.     

In vitro Studies of Antimicrobial Activity of Crude Extracts of the Indian Grasses Dhaman (Cenchrus ciliaris) and Kala-Dhaman (Cenchrus setigerus)

The aim of present study was to investigate the antimicrobial activity of Cenchrus ciliaris and Cenchrus setigerus extracts in order to use it as a possible source for new antimicrobial substances against important human pathogens. Crude extracts of the stem of Cenchrus ciliaris and Cenchrus setigerus were evaluated against some medically important pathogens viz. Escherichia coli, Raoultella planticola, Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis, Enterobacter aerogenes, Candida albicans and Aspergillus flavus. The dried and powdered stems were successively extracted with hexane, toluene, isopropyl alcohol, acetone and ethanol using soxhlet assembly. The antimicrobial activity assay was done by both disc diffusion and serial dilution methods. Isopropyl alcohol extract of Cenchrus setigerus showed highest activity against Escherichia coli. The test pathogens were more sensitive to the isopropyl alcohol, acetone and ethanol extracts than to the hexane and toluene extracts except against Bacillus subtilis. Result reveals that the most bioactive compound was cycloleucolenol-9,19-cycloergost-24 (28)-en-3-ol, 4, 14-dimethyl acetate in both the species of Cenchrus grass, (19.15%) in isopropanol extract of Cenchrus setigerus whereas, (14.03%) in acetone extract of Cenchrus ciliaris.     

Hormetic Responses of Lonicera Japonica Thunb. To Cadmium Stress

The hormetic responses of Lonicera japonica Thunb. to cadmium (Cd) stress were investigated in a hydroponic experiment. The present results showed that root length and total biomass dry weight increased in comparison with the control at low concentrations Cd. The height of the plant exposed to 2.5 and 5 mg L^-1 Cd increased significantly by 11.9% and 12.8% relative to the control, and with the increase of Cd concentrations in the medium, plant height began to decrease. The responses of photosynthetic pigments contents and relative water content to Cd stress had a similar trend, which all showed significantly an inverted U-shaped dose–response curve and confirmed that the stimulatory effect of low concentrations Cd occurred in the plant. Furthermore, L. japonica, as a new Cd-hyperaccumulator, could be considered as a new plant model to study the underlying mechanisms of the hormesis.     

Cytotoxic fungi--an overview.

Among fungal toxins causing organ damage in the human body, amatoxins and orellanine remain exceptional. Amatoxins, a group of bicyclic octapeptides occurring in some Amanita, Galerina and Lepiota species, induce deficient protein synthesis resulting in cell death, but might also exert toxicity through inducing apoptosis. Target organs are intestinal mucosa, liver and kidneys. Poisoning will result in dehydration and electrolyte derangement, liver necrosis and possibly kidney damage. In established poisoning the mainstay of treatment is optimum symptomatic and supportive care. No specific treatment is available, but some pharmaceuticals, like silibinin, benzylpenicillin and acetylcysteine, might have a role in limiting the extent of hepatic damage. Orellanine is a nephrotoxic bipyridine N-oxide found in some Cortinarius species. Its mechanism of action is not fully understood, but it has been shown to inhibit protein synthesis and to generate free oxygen radicals. As early symptoms often are lacking or vague, poisoning may initially be overlooked or misinterpreted and the patients usually present with established renal damage. Supportive care is the only therapeutic option. Tricholoma equestre might contain a myotoxin and repeated ingestion may cause significant rhabdomyolysis. Ingestion of Amanita smithiana and A. proxima has been reported to result in kidney damage. Gyromitrin, a toxic compound that is converted to hydrazines in the stomach, occurs in some Gyromitra species. It is mainly neurotoxic, but may also induce moderate hepatic damage and haemolysis.     

Toxicity assessment of crude and partially purified extracts of marine Synechocystis and Synechococcus cyanobacterial strains in marine invertebrates

Among the Cyanoprokaryota, the genera Synechocystis and Synechococcus have rarely been studied with respect to potential toxicity. This is particularly true with marine environments where studies about the toxicity of cyanobacteria are restricted to filamentous forms at the warmer temperate and tropical regions and also to filamentous forms at cold seas such as the Baltic Sea. In this study, we describe the effects of cyanobacterial strains of the Synechocystis and Synechococcus genera isolated from the marine coast of Portugal, on marine invertebrates. Crude and partially purified extracts at a concentration of 100 mg/ml of freeze-dried material of the marine strains were tested for acute toxicity in nauplii of the brine shrimp Artemia salina, in the rotifer Brachionus plicatillis and in embryos of the sea urchin Paracentrotus lividus and the mussel Mytilus galloprovincialis. The cyanobacterial extracts, especially the crude extract, had an impact on A. salina nauplii. No significant toxic effects were registered against the rotifer. A negative impact of all strains was recorded on the embryonic development of the sea urchin, with toxic effects resulting in an inhibition of embryogenesis or development of smaller larvae. To the mussel embryos, the effects of cyanobacterial extracts resulted in a complete inhibition of embryogenesis. The results of all assays indicate that Synechocystis and Synechococcus marine strains contained toxic compounds to marine invertebrates.     

Toxic dinoflagellates (Dinophyceae) from Rarotonga, Cook Islands

Dinoflagellate species isolated from the green calcareous seaweed, Halimeda sp. J.V. Lamouroux, growing in Rarotongan lagoons, included Gambierdiscus australes Faust & Chinain, Coolia monotis Meunier, Amphidinium carterae Hulburth, Prorocentrum lima (Ehrenberg) Dodge, P. cf. maculosum Faust and species in the genus Ostreopsis Schmidt. Isolates were identified to species level by scanning electron microscopy and/or DNA sequence analysis. Culture extracts of G. australes isolate CAWD149 gave a response of 0.04 pg P-CTX-1 equiv. per cell by an N2A cytotoxicity assay (equivalent to ca 0.4 pg CTX-3C cell⁻¹). However, ciguatoxins were not detected by LC-MS/MS. Partitioned fractions of the cell extracts potentially containing maitotoxin were found to be very toxic to mice after intraperitoneal (i.p.) injection. A. carterae was also of interest as extracts of mass cultures caused respiratory paralysis in mice at high doses, both by i.p. injection and by oral administration. The Rarotongan isolate fell into a different clade to New Zealand A. carterae isolates, based on DNA sequence analysis, and also had a different toxin profile. As A. carterae co-occurred with G. australes, it may contribute to human poisonings attributed to CTX and warrants further investigation. A crude extract of C. monotis was of low toxicity to mice by i.p. injection, and an extract of Ostreopsis sp. was negative in the palytoxin haemolysis neutralisation assay.     

Immunomodulatory Effects of Triphala and its Individual Constituents: A Review

The role of plant extracts and Ayurvedic polyherbal preparations in treating various ailments has been acknowledged since time immemorial. Studies based on the effect of these extracts in treatment of different diseases have also been well documented. Indian medicinal literature also emphasizes the synergistic effect of polyherbal drugs in restoring and rejuvenating immune system. This review focuses on the immunomodulatory potential of the polyherbal preparation, Triphala and its three constituents, Terminalia bellerica, Terminalia chebula and Emblica officinalis. The role of Triphala and its extract has been emphasized in stimulating neutrophil function. Under stress condition such as noise, Triphala significantly prevents elevation of IL-4 levels as well as corrects decreased IL-2 and IFN-γ levels. Under the condition of inflammatory stress its immunosuppressive activity is attributed to its inhibitory action on complement system, humoral immunity, cell mediated immunity and mitogen-induced T-lymphocyte proliferation. The aqueous and alcoholic extracts of the individual constituents reportedly enhance especially the macrophage activation due to their free radical scavenging activity and the ability to neutralize reactive oxygen species. This study thus concludes the use of Triphala and its three individual constituents as potential immunostimulants and/or immunosuppressants further suggests them to be a better alternative for allopathic immunomodulators.     

Effect of Plant Extracts Formulated in Different Ointment Bases on MDR Strains

Extracts of Aloe vera whole plant, Eucalyptus globulus leaves, Ficus infectoria bark, Ficus religiosa bark and Piper betel leaves were studied for antibacterial activity on resistant and sensitive strains, isolated from skin and soft tissue infections. A combination of hot alcoholic extracts of Ficus infectoria, Ficus religiosa and Piper betel were found to be more effective against all the isolates. The combined extract was formulated in different ointment bases such as polyethylene glycol, gelatin, sodium alginate, carbopol, cream base and honey. These were then evaluated to find a suitable base for preparation of an ointment. In vitro study of the release of antimicrobials and kill-time studies of the herbal ointments was carried out against multi-drug resistant isolate of Pseudomonas. The ointment showed bactericidal activity within 2 h against the resistant strain of Pseudomonas spp.     

Structure-Based Design of Substituted Piperidines as a New Class of Highly Efficacious Oral Direct Renin Inhibitors

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First report of (homo)anatoxin-a and dog neurotoxicosis after ingestion of benthic cyanobacteria in The Netherlands

In April and May 2011, three dogs died and one dog became ill after swimming in Lake IJmeer (The Netherlands). At the time, the lake was infested with the benthic cyanobacterial species Phormidium. A Eurasian Coot (Fulica atra) and a Black-headed Gull (Chroicocephalus ridibundus) also died near Lake IJmeer in the same period. One of the dogs and both birds were subjected to a pathological investigation. Furthermore, the Phormidium mat; algal samples from the dikes; contents of the animals’ digestive systems and organ tissues were analysed for the following cyanobacterial toxins: (homo)anatoxin-a; (7-deoxy-)cylindrospermopsin; saxitoxins and gonyautoxins by LC-MS/MS. Samples were also analysed for the nontoxic (homo)anatoxin-a metabolites dihydro(homo)anatoxin-a and epoxy(homo)anatoxin-a. The dog necropsy results indicated neurotoxicosis and its stomach contained Phormidium filaments. Anatoxin-a was detected in the Phormidium mat (272 μg g⁻¹ dry weight, stdev 65, n = 3) and in the dog’s stomach contents (9.5 μg g⁻¹ dry weight, stdev 2.4, n = 3). Both samples also contained the anatoxin-a metabolite dihydroanatoxin-a, and a trace of homoanatoxin-a was detected in the Phormidium mat. The birds were in bad nutritive condition at the time of necropsy and their stomachs and intestines did not contain any cyanobacterial material. Furthermore, no cyanobacterial toxins were detected in their stomachs, intestines and organs and they both had lesions that are not associated with cyanobacterial intoxication. This is the first report of anatoxin-a and homoanatoxin-a occurrence in The Netherlands, these toxins have likely caused the deaths of three dogs. The birds probably died of other causes. Dutch recreational waters are at this moment only screened for pelagic cyanobacterial species, the current bathing water protocol therefore does not protect humans and animals from negative effects of blooms of benthic cyanobacteria.