西沙海绵Agelas aff. Nemoechinata化学成分研究△

目的 研究中国西沙海绵Agelas aff. Nemoechinata 二氯甲烷/甲醇部分的化学成分。方法 运用薄层色谱、硅胶柱色谱、Sephadex LH-20凝胶柱色谱、MPLC、HPLC等分离方法对该海绵化学成分进行分离纯化;利用核磁共振、质谱等结构鉴定技术,并结合文献,鉴定化合物的结构。结果 从海绵甲醇粗提物的二氯甲烷/甲醇部分分离鉴定了7个化合物：agelasine B (1)、2-oxo-agelasine B (2)、2’-oxo-agelasidine C (3)、2-甲酸吡咯负离子 (4)、2-甲酰胺吡咯 (5)、9-甲基腺嘌呤 (6)和尿嘧啶 (7)。结论 化合物1、2、3、4和6均为首次从该种分离得到。     

皂角刺抗肿瘤活性成分的分离鉴定与活性测定

目的分离鉴定皂角刺中抗肿瘤活性成分。方法用四甲基偶氮唑盐(MTT)比色法,结合硅胶、葡聚糖凝胶等色谱方法追踪分离皂角刺抗肿瘤活性成分,根据理化性质和波谱数据鉴定化学结构,用半数抑制浓度(IC50)评价其抗肿瘤活性。结果从皂角刺中分离得到8个化合物,分别为黄颜木素(1)、槲皮素(2)、3-βacetoxyolean-12-en-28-oic acid(3)、木栓酮(4)、棕榈酸(5)、白桦醇(6)、β-谷甾醇(7),胡萝卜苷(8)。化合物1、3对7种体外培养的肿瘤细胞抑制作用较好,在测定浓度范围内剂量依赖关系良好;化合物3对Bel-7402、HeLa、HT1080、KB、A549、SGC-7901、Heps等7种肿瘤细胞株生长增殖均具有良好的抑制作用,IC50为11.61~18.73 mg.L-1;化合物1对除A549之外的6种肿瘤细胞株抑制作用良好,IC50为11.34~19.32 mg.L-1。结论化合物2~6和8为首次从皂角刺中分离;化合物1、3的抗肿瘤活性为皂角刺中首次发现。     

角果木内生真菌Penicillium sp. J54代谢产物及活性研究

目的研究红树植物角果木内生真菌Penicilliumsp.J54产生的活性次生代谢产物。方法采用多种柱色谱技术进行分离纯化,根据化合物的理化常数和波谱数据鉴定结构,利用MTT法测定各化合物的体外细胞毒活性。结果从角果木内生真菌Penicilliumsp.J54发酵液中分离了8个化合物,分别鉴定为:aervecdysteriod D(1)、citroside A(2)、3-methoxyepicoccone(3)、2,4-二羟基-3,5,6-三甲基苯甲醛(4)、mycosphine B(5)、mycosphine A(6)、5-羟甲基糠醛(7)、对羟基苯乙醇(8)。结论其中化合物1~5均为首次从角果木内生真菌分离得到,并首次报道了化合物4的核磁数据,活性测试结果表明化合物3对肿瘤细胞株K-562生长具有抑制作用。     

中华隐孔菌子实体化学成分及细胞毒活性研究

目的 分离鉴定中华隐孔菌(Cryptoporus sinensis Sheng H. Wu &; M. Zang)子实体的化学成分。方法 采用硅胶柱色谱、ODS柱色谱、Sephadex LH-20柱色谱、HPLC 等分离方法,对中华隐孔菌子实体甲醇提取物的二氯甲烷萃取部分进行分离,根据理化性质和波谱数据鉴定化合物结构。采用MTT法对化合物进行细胞毒活性测定。结果 分离鉴定了4个已知的隐孔菌酸化合物,分别是隐孔菌酸B(1)、隐孔菌酸B甲酯(2)、隐孔菌酸G(3)、1,1″-二羧基隐孔菌酸D(4)。抗肿瘤活性筛选表明,化合物1~4具有弱的细胞毒活性,对肿瘤细胞PC-3、PANC-1、A549和MCF-7的半数抑制浓度大于100 µmol•L^-1。结论 化合物1~4 均是首次从该种真菌中分离得到。 关键词：中图分类号：     

盐碱地真菌棘孢曲霉Aspergillus aculeatus的化学成分研究△﹡

目的 对一株具有抗肿瘤活性的滨州盐碱地真菌棘孢曲霉Aspergillus aculeatus的活性次级代谢产物进行研究。方法 采用硅胶柱层析、LH-20凝胶色谱和半制备高效液相色谱分离纯化代谢产物,通过理化性质、波谱手段结合X-ray单晶衍射技术鉴定化合物,采用MTT法测试所得化合物对肿瘤细胞A549的增殖抑制活性。结果 从棘孢曲霉Aspergillus aculeatus中分离得到8个化合物(1～8),分别鉴定为5-Hydroxymethyl-2-furoic acid (1)、Isorhodoptilometrin (2)、Secalonic acid F (3)、Emodin (4)、Protocatechuic acid (5)、Altechromones B (6)、Cyclo (L-Tyr-L-Leu) (7)和Cyclo (L-Phe-L-Ala) (8)。化合物3对A549细胞具有一定的增殖抑制活性,其IC50值为14.9 μM。结论 首次研究了来源于盐碱地真菌棘孢曲霉Aspergillus aculeatus的活性次级代谢产物,并首次报道secalonic acid F对A549肿瘤细胞增殖抑制活性。     

海洋真菌Aspergillus sp. SCS-KFD03化学成分研究

目的 对海洋真菌Aspergillus sp. SCS-KFD03的发酵液中化学成分进行分离鉴定,并测定其生物活性。 方法 采用硅胶柱色谱、Sephadex LH-20凝胶柱色谱和高效液相色谱等技术进行分离纯化,运用各种波谱方法对分离所得化合物进行结构鉴定,并测定化合物乙酰胆碱酯酶和α-糖苷酶抑制活性。结果 分离鉴定了9个化合物,经鉴定为phomaligol A1（1）、5-（乙酰氧基甲基）呋喃-3-酸（2）、 phomapyrone C（3）、4-羟基异苯并呋喃-1(3H)-酮（4）、penicillivinacine（5）、22(E)-5α,8α-epidioxyergosta-6,22-dien-3β-ol（6）、lucidal（7）、dankasterone A（8）、bis-(2-methylheptyl)-phthalate（9）,其中化合物4为新天然产物。化合物5、6、7和9具有较弱的乙酰胆碱酯酶抑制的活性,化合物5具有强于阳性药阿卡波糖的α-糖苷酶抑制活性,8和9的α-糖苷酶抑制活性与阳性药相当。结论 化合物1~9均为首次从海洋曲霉属真菌Aspergillus sp. SCS-KFD03中分离得到,部分化合物具有乙酰胆碱酯酶和α-糖苷酶的抑制活性。     

一种西沙掘海绵Dysidea sp.的化学成分研究

目的 对西沙掘海绵Dysidea sp.进行化学成分研究;方法 运用正相硅胶柱色谱、反相ODS柱色谱、凝胶Sephadex LH-20柱色谱以及高效液相色谱(HPLC)等多种分离手段对西沙掘海绵Dysidea sp.化学成分进行分离纯化;并通过理化性质、波谱学数据等结构信息鉴定其化合物的结构。结果发现：从西沙掘海绵Dysidea sp.中分离鉴定了8个化合物,分别为dictyoceratin C（1）、dactyloquinone B（2）、aminoquinone（3）、dictyoceratin A（4）、dactyloquinone D（5）、dactyloquinone E（6）、(1R*,2E,4R*,7E,10S*,11S*,12R*)-10,18-diacetoxydolabella-2,7-dien-6-one（7）和?,?-unsaturated ester（8）,结论 化合物1?6和8均为首次从该属海绵中分离得到。     

黄边灵芝中一个新的羊毛脂烷型三萜

采用硅胶柱色谱、MCI柱色谱、制备薄层色谱和半制备高效液相色谱等分离手段,从黄边灵芝Ganoderma luteomarginatum乙醇提取物的乙酸乙酯萃取部位中分离得到4个羊毛脂烷型三萜化合物,根据NMR、MS、IR数据和X-ray单晶衍射分析,分别鉴定为(24S,25R)-ganodermanontriol-25-ethyl ether (1)、ganodermanontriol (2)、ganodermanondiol (3)、hainanaldehyde A (4),其中化合物1为新化合物,所有化合物均为首次从黄边灵芝中分离得到。采用MTT法测定化合物1～3对人肺癌细胞A549、胃癌细胞HGC-27、肝癌细胞SMMC-7721、宫颈癌细胞HeLa的细胞毒活性,结果显示化合物1～3对4种肿瘤细胞具有不同程度的抑制增殖作用,尤其化合物1对A549和HGC-27细胞表现出了显著的细胞毒活性, IC₅₀分别为4.29±0.89和5.63±0.90μmol·L^-1。     

中国南海海绵Iotrochota sp.的化学成分研究D*

目的 研究中国南海海绵Iotrochota sp.的化学成分。方法 应用正、反相硅胶柱色谱、Sephadex LH-20凝胶柱色谱、半制备反相高效液相色谱(RP-HPLC)等多种色谱手段,对海绵Iotrochota sp.的二氯甲烷提取物进行分离纯化,从中得到6个单体化合物,运用现代波谱技术结合文献报道对其进行结构鉴定,采用MTT法对分离得到的6个化合物进行人高转移肝癌细胞(LM3)和人肝癌细胞(HepG2)的体外抗肿瘤活性测试。结果 分离得到6个化合物,包括4个吲哚生物碱类化合物(1-4)及2个酚类化合物(5、6),分别鉴定为：1H-indole-3-carbaldehyde(1)、5-bromo-1H-indole-3-carbaldehyde(2)、1H-indole-3-hydroxyacetyl(3)、5-bromo-3-(hydroxylacetyl)-indole(4)、4-hydroxy-benzeneethanol(5)、3-hydroxy- benzeneethanol(6)。这些化合物均为首次从海绵Iotrochota sp.中分离得到,化合物2和4为C-5溴代吲哚生物碱,本文首次对其NMR数据进行了报道。体外抗肿瘤活性测试显示,化合物3对LM3及HepG2细胞株显示不同程度的抑制活性,IC₅₀值分别为29.3及46.3 μM;其他化合物不显示抑制作用(IC₅₀>50 μM)。     

中国南海蜂海绵Haliclona cymae formis的化学成分研究

目的研究中国南海蜂海绵属Haliclona cymaeformis的化学成分。方法运用正相硅胶、反相硅胶(ODS)和凝胶(Sephadex LH-20)等多种柱色谱手段对化合物进行分离纯化;通过理化性质和波谱数据,结合文献对照,鉴定化合物的结构。结果从海绵H.cymaeformis的乙醇提取物中共分离鉴定了11个单体化合物:24-亚甲基胆甾醇(1),5α,8β-epidioxy-cholesta-6-en-3-ol(2),cholesta-7-en-3β,5α,6β,9α-tetraol(3),胆甾醇(4),3-吲哚甲酸(5),尿嘧啶(6),胸腺嘧啶(7),尿嘧啶核苷(8),胸腺嘧啶核苷(9),尿嘧啶脱氧核苷(10)和胸腺嘧啶脱氧核苷(11)。结论化合物1~11均为首次从该海绵中分离得到。细胞毒活性测试结果表明,化合物3对慢性髓原白血病细胞(K562)和人肝癌细胞(SMMC-7721)的增殖显示了较强的生长抑制活性。     

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.     

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.     

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.     

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.