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1.
Job Kuijt 《Brittonia》2009,61(2):144-162
Twelve new South American species of Loranthaceae (Aetanthus, Cladocolea, Oryctanthus, and Struthanthus) and Viscaceae (Dendrophthora and Phoradendron) are described and illustrated: Aetanthus trifolius, Cladocolea rostrifolia, Dendrophthora lanceolata, Dendrophthora rotundata, Dendrophthora tenuis, Dendrophthora werffii, Oryctanthus minor, Phoradendron pascoi, Phoradendron vasquezianum, Struthanthus apiculatus, Struthanthus schultesii, and Struthanthus sessiliflorus. Additionally, Cladocolea alternifolia, previously thought to be probably extinct, is reported to occur on Ilha Grande, just west of Rio de Janeiro, Brazil.  相似文献   

2.
Sixteen new species of the genus Zorochros Thomson 1859 from China, Indonesia, Malaysia, Nepal and Thailand are described and illustrated, a key to the species of the Zorochros indicus group is given, and new records on already known species are provided. New species: Z. ahrensi n. sp., Z bingkorensis n. sp., Z. dabieshanensis n. sp., Z. dolini n. sp., Z. hartmanni n. sp., Z. hubeiensis n. sp., Z. karnaliensis n. sp., Z. magnificus n. sp., Z. naniensis n. sp., Z. nigredos n. sp., Z. platiai n. sp., Z schawalleri n. sp., Z. schmidti n. sp., Z. senaroensis n. sp., Z. theodori n. sp., and Z. tongshanensis n. sp.  相似文献   

3.
Uncaria rhynchophylla (Gouteng) is a famous traditional Chinese medicine used for psychiatric and hypotensive purposes in China. In this study, the ethyl acetate (EtOAc) part of U. rhynchophylla was revealed with protein tyrosine phosphatase 1B (PTP1B) inhibitory activity. Subsequent investigation on the EtOAc part yielded one new triterpenoid, 3β-formyloxy-6β,19α-dihydroxyurs-12-en-28-oic acid (1) and four known ones, 3β,6β,19α-trihydroxyurs-12-en-28-oic acid (2), 2-oxopomolic acid (3), 3β,19α-dihydroxy-6-oxo-olean-12-en-28-oic acid (4) and sumaresinolic acid (5). The structure of compound 1 was determined by extensive HRESIMS, IR, 1D and 2D NMR spectroscopic analyses. Two ursane-type triterpenoids (2 and 3) showed selective inhibition on PTP1B with IC50 values of 48.2 and 178.7 μM. The enzyme kinetic study suggested that compounds 2 and 3 were mix-type inhibitors on PTP1B with Ki values of 15.6 and 132.5 μM. This investigation manifests the antidiabetic potency of U. rhynchophylla with triterpenoids as the active constituents.  相似文献   

4.
Paulo H. Labiak 《Brittonia》2011,63(1):139-149
Stenogrammitis , a new genus of grammitid ferns, is segregated from Lellingeria based on morphological and molecular evidence. It differs from Lellingeria by linear leaves usually less than 5 mm wide, clathrate iridescent rhizome scales that are glabrous except for a single apical cilium, veins unbranched and only one per segment, fertile veins usually with the dark sclerenchyma visible beneath the sporangia, and x = 33. In contrast, Lellingeria has broader laminae, veins pinnate within the segments, and fertile veins not visible beneath the sporangia. Melpomene, which is sister to Stenogrammitis and Lellingeria, differs from those two genera by reddish setae on the leaves and rhizome scales papillate at the apex. Some species of Stenogrammitis are also distinctive by hemidimorphic laminae that have the fertile portion less dissected than the sterile. Stenogrammitis is pantropical and currently comprises 24 species, 12 of which occur in the Neotropics, six in Africa, four in Madagascar, and two on Pacific Islands. New combinations are made for Stenogrammitis aethiopica, S. anamorphosa, S. ascensionensis, S. boivinii, S. delitescens, S. jamesonii, S. hartii, S. hellwigii, S. hildebrandtii, S. limula, S. luetzelburgii, S. myosuroides, S. nutata, S. oosora, S. paucipinnata, S. prionodes, S. pumila, S. ruglessii, S. rupestris, S. saffordii, S. strangeana, S. tomensis, S. subcoriacea, and S. wittigiana. Lectotypifications are made for Grammitis muscosa, Polypodium itatiayense, P. oosorum var. micropecten, P. serrulatum forma major, P. serrulatum forma minor, S. luetzelburgii, S. myosuroides, and S. wittigiana. Illustrations are presented for the diagnostic characters of the genus, as well as a map with the geographical distribution.  相似文献   

5.
Taxonomic changes are made to reflect a reassessment of morphology based on the results of molecular phylogenetic studies. A new genus, Davilanthus, is described to include six species that collectively form the sister group to Simsia, and includes the following species transferred from Viguiera: Davilanthus davilae, Davilanthus hidalgoanus, Davilanthus hypargyreus, Davilanthus huajuapanus, Davilanthus purpusii, and Davilanthus sericeus. Three species formerly placed in Viguiera ser. Grammatoglossae are transferred to Simsia: Simsia benziorum, Simsia ovata, and Simsia rhombifolia.  相似文献   

6.
Four (14) new and seven known limonoids were isolated from the EtOH extract of the fruits of Melia toosendan. The structures of the new compounds were established on the basis of spectroscopic methods to be 12-O-methyl-1-O-deacetylnimbolinin B (1), 12-O-methy-1-O-tigloyl-1-O-deacetylnimbolinin B (2), 12-O-ethylnimbolinin B (3), and 1-O-cinnamoyl-1-O-debenzoylohchinal (4). Additionally, two new tirucallane-type triterpenoids, named meliasenins S (5) and T (6), were obtained from the same fractions during purification of the limonoids.  相似文献   

7.
Diterpenoid alkaloids are compounds of pharmacological interest. Forty four C19 norditerpenoid (NDAs) and 23 C20 diterpenoid (DAs) alkaloids isolated from Aconitum, Delphinium and Consolida species were tested for their insecticidal effects (antifeedant and toxic) on Spodoptera littoralis and Leptinotarsa decemlineata, their cytotoxicity on tumoral cell lines with several multidrug resistance mechanisms, and their antiparasitic effects against Trypanososma cruzi and Leishmania infantum. Overall, C19 norditerpene alkaloids (NDAs) resulted better insect antifeedants and post-ingestive toxicants than the related C20 diterpene alkaloids (DAs). Their antifeedant or insecticidal potencies did not parallel their reported nAChR binding activity, but did correlate␣with the␣agonist/antagonist insecticidal/ antifeedant model proposed for nicotininc insecticides.␣Among the most potent antifeedants (EC50 < 0.2 μg/cm2) are␣the NDAs 1,14 diacetylcardiopetaline (10),␣18-hydroxy-14-O-methylgadesine (34) and 14-O-acetyldelectinine (28) (to CPB) and the DA 19-oxodihydroatisine (55) (to S.␣littoralis). DAs had strong antiparasitic effects with molecular selectivity while NDAs were inactive. Delphigraciline (53), 15,22-O-Diacetyl-19-oxo-dihydroatisine (56), azitine (64) and isoazitine (65) were active against L. infantum promastigotes and had a moderate effect on T. cruzi epimastigotes, while atisinium chloride (59) and 13-oxocardiopetamine (48) had a potent effect on T. cruzi epimastigotes. These compounds were not toxic to the host cell, significantly reduced parasite infection capacity and severely affected the multiplication of their extracellular forms. Several NDAs exhibited selective cytotoxicity to cancerous cells and some of these had irreversible effects on SW480, HeLa and SkMel25 cell lines (neoline 5, pubescenine 16, 14-deacetylajadine 26, lycoctonine 27, dehydrotakaosamine 35, and ajadelphinine 38). These cytotoxic effects could be related to the inhibition of ATP production.  相似文献   

8.
Lu  Chunhua  Xie  Fei  Shan  Chuan  Shen  Yuemao 《Applied microbiology and biotechnology》2017,101(6):2273-2279

Two novel cyclic hexapeptides designated actinosynneptides A (1) and B (2), together with three tryptophan containing diketopiperazines, namely cyclo(L-Trp-L-Trp) (3), cyclo(L-Trp-N-MeL-Trp) (4), and cyclo(N-MeL-Trp-N-MeL-Trp) (5), were isolated from the culture of the genetically engineered strain HGF052::asm18 derived from Actinosynnema pretiosum ATCC31565. Their structures were elucidated on the basis of spectroscopic analyses and single-crystal X-ray diffractions. Compound 1 is the first example of 3-amino-6-hydroxy-2-piperidone-containing cyclic peptides, and 1 and 2 showed moderate cytotoxic activities against HeLa and PC3 cell lines.

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9.
【目的】通过基因组挖掘的方法,研究红树林来源白骨壤链霉菌Streptomyces avicenniae 9-9中多环稠合大环内酰胺(PTMs)类化合物的结构多样性。【方法】通过生物信息学分析白骨壤链霉菌基因组序列,寻找PTMs类化合物的生物合成相关基因;利用UPLC-MS/MS技术对该菌的次级代谢产物进行分析。【结果】在白骨壤链霉菌基因组中发现PTMs生物合成基因簇(aviA-D);从菌液提取物中鉴定出5个PTMs类化合物,其中包括ikarugamycin(化合物1)和capsimycin B(化合物2);基于PTMs类化合物5-6-5环类型的MS/MS碎裂规律,对化合物3–5的结构进行了推测。【结论】红树林来源白骨壤链霉菌S.avicenniae 9-9具有产生5-6-5环类型的PTMs类化合物的能力。  相似文献   

10.
An endophytic fungus was isolated from the root of the medicinal plant Moringa oleifera Lam. Based on analyzing the rDNA sequence, the fungus was identified as Nigrospora sp. This is the first report of the isolation of endophytic Nigrospora from M. oleifera. By bioassay-guided fractionation, four antifungal secondary metabolites were isolated from liquid cultures of the fungus Nigrospora sp. LLGLM003, and their chemical structures were determined to be griseofulvin (1), dechlorogriseofulvin (2), 8-dihydroramulosin (3) and mellein (4) on the basis of spectroscopic analyses. Compound 2, 3 and 4 were isolated from Nigrospora sp. for the first time. In vitro antifungal assay showed that griseofulvin displayed clear inhibition of the growth of 8 plant pathogenic fungi. Dechlorogriseofulvin and mellein exhibited only weak antifungal activities, whereas 8-dihydroramulosin displayed no antifungal activities.  相似文献   

11.
Summary. The Adoretini of the Malagasy endemic genus Adorodocia Brenske 1893 is revised. Fourteen new species and one new subspecies are described and compared with their most closely related species: A. constricta n. sp., A. cuccodoroi n. sp., A. flava n. sp., A. liliae n. sp., A. marginata n. sp., A. peyrierasi n. sp., A. pseudoconstricta n. sp., A. pseudoflava n. sp., A. pseudostrigata n. sp., A. recta n. sp., A. robusta n. sp., A. sogai n. sp., A. vadoni n. sp., A. viettei n. sp. and A. vittaticollis flavipes n. ssp. The synonymy between Adoretus strigatus Waterhouse 1878, and Pseudadorodocia aenigma Arrow 1901, is confirmed. Thus, based on the results of this study, the genus Adorodocia includes 16 species, and one of them is represented by two subspecies. Diagnostic characters to separate the species in the genus deal mostly with the shape of parameres, color of body and legs, shape of pronotum and female eighth tergite, setation of pronotum and elytra. Key to species, diagnoses and distribution for each species are provided. Endophallus and female genitalia are illustrated for the first time for this genus.  相似文献   

12.
为了解黄皮[Clausena lansium(Lour.)Skeels]果皮中的抗菌活性成分,采用硅胶柱色谱、Sephadex LH-20凝胶柱色谱等方法,从黄皮果皮的乙醇提取物中分离得到10个化合物,经波谱学分析鉴定为:lansine(1)、3-甲酰基咔唑(2)、3-甲酰基-6-甲氧基咔唑(3)、6-甲氧基咔唑-3-羧酸甲酯(4)、(6R,7E,9S)-9-羟基-4,7-巨豆二烯-3-酮(5)、7-羟基香豆素(6)、8-羟基呋喃香豆素(7)、辛黄皮酰胺(8)、对羟基肉桂酸甲酯(9)和胡萝卜苷(10)。其中化合物5和9为首次从黄皮属植物中分离得到,化合物8的碳谱数据是首次报道。用滤纸片琼脂扩散法测定化合物的抗菌活性,结果表明,化合物1、2、3、6、7和9对金黄色葡萄球菌(Staphylococcus aureus)有抑制作用。这有利于更好地开发利用黄皮这一药食两用的水果资源。  相似文献   

13.

目的 获取绩效优秀妇产科医师区别于绩效普通妇产科医师的胜任特征。方法 在编制医师胜任特征词典的基础上,以10名绩优和10名绩平医师为研究对象,采用行为事件访谈法收集数据,对不同绩效组医师胜任特征的频次、平均等级分值和最高等级分值的差异采用Wilcoxon秩和检验进行分析。结果 鉴别胜任特征包括严谨细致、团队合作等18项特征。结论 鉴别胜任特征对妇产科医师人力资源规划、招聘、培训有一定参考价值。

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14.
The 11 Malagasy species of the genus Ecnomus McLachlan, 1864 that do not belong to the psychomyiellodes species group are studied. One of them (Ecnomus salgiel Malicky, 2015) was recently described from Nosy Be Island. Ten are new and described: Ecnomus felix n. sp., E. dobignyi n. sp., E. matsaboryi n. sp., E. granjoni n. sp., E. commersoni n. sp., E. menavavae n. sp., E. ikopaensis n. sp., E. rubermortis n. sp., E. evidens n. sp., and E. tendroensis n. sp. All are endemic to Madagascar. Their distributions on the island are briefly described according to ecological data.  相似文献   

15.

The formation of biogenic fabrics in limestone by two fungi, Serpula himantioides and a polymorphic fungal isolate from limestone identified as a Cephalotrichum (syn. Doratomyces) sp., was investigated. The fungal cultures were grown in laboratory microcosms consisting of Carboniferous limestone and after 21 d incubation at 25°C, biomineralization of fungal filaments was observed. Environmental electron scanning microscopy (ESEM) and X-ray micro-analysis (EDXA) of crystalline precipitates on the hyphae of S. himantioides demonstrated that the secondary crystals exhibited different crystalline forms but were similar in elemental composition to the original limestone. Powder X-ray diffraction (XRD) of crystalline precipitates showed they were composed of a mixture of calcite (CaCO 3 ) and calcium oxalate monohydrate (CaC 2 O 4 · H 2 O). Analysis of crystals precipitated on the hyphae of the limestone isolate, using ESEM and EDXA, showed that the crystals exhibited similar morphological characteristics and elemental composition to the original limestone. XRD showed that they were composed solely of calcite (CaCO 3 ) or of calcite with some calcium oxalate dihydrate (CaC 2 O 4 · 2H 2 O). These results provide direct experimental evidence for the precipitation of calcite (CaCO 3 ) and also secondary mycogenic minerals, on fungal hyphae in low nutrient calcareous environments, and suggest that fungi may play a wider role in the biogeochemical carbon cycle than has previously been appreciated.  相似文献   

16.
【背景】目前国内学者已发表60个马鞍菌属物种,但山西省尚缺乏马鞍菌属真菌分布的系统性报道。【目的】调查我国山西省马鞍菌属的种类组成及地理分布。【方法】采集标本,对其进行详细的形态特征描述,并提取DNA,测定热激蛋白(heat shock protein, hsp)和核糖体大亚基(large subunit, LSU)序列,基于贝叶斯法(Bayesian inference, BI)和最大似然法(maximum likelihood, ML)构建分子系统发育树。【结果】鉴定结果表明这3个马鞍菌属物种分别为类帽状马鞍菌(Helvella capucinoides)、丹麦马鞍菌(H. danica)和柔毛马鞍菌(H. pubescens)。它们在形态上与模式标本的描述基本一致。基于hsp和LSU的系统发育关系分析也支持形态学的鉴定结果。【结论】参考我国截至目前已报道的马鞍菌属物种,确定这3个种均为中国新记录种。  相似文献   

17.
Abstract

The biotransformation of arenobufagin (1) and cinobufotalin (2), isolated from the natural medicine Chan Su, by Alternaria alternata AS 3.4578 was carried out. Incubation of 1 and 2 afforded six metabolites: 3-oxo-arenobufagin (1a), ψ-bufarenogin (1b), 3-oxo-ψ-bufarenogin (1c), 3-oxo4-derivative of cinobufotalin (2a), 3-oxo-cinobufotalin (2b) and 12β-hydroxycinobufotalin (2c). Among them, metabolites 1a, 1c and 2c are new compounds and their structures were characterized on the basis of their spectroscopic data (NMR, MS and IR). Compounds 1, 2, 1b, 2a and 2b were evaluated for their cytotoxicity against HepG2 and MCF-7 human cancer cells, and all of them showed significant inhibitory activities.  相似文献   

18.
The in vivo and in vitro antiandrogenic activity of four new progesterone derivatives: 4-bromo-17α-(p-fluorobenzoyloxy)-4-pregnene-3,20-dione 1,4-bromo-17α-(p-chlorobenzoyloxy)-4-pregnene-3,20-dione 2, 4-bromo-17α-(p-bromobenzoyloxy)-4-pregnene-3,20-dione 3 and 4-bromo-17α-(p-toluoyloxy)-4-pregnene-3, 20-dione 4 was determined. These compounds were evaluated as antiandrogens on gonadectomized hamster prostate and reduced the weight of the prostate glands in gonadectomized hamsters treated with testosterone 5 (T) or dihydrotestosterone 6 (DHT) in a similar manner to that of commercially available finasteride, thus indicating a potent in vivo effect. The in vitro studies showed that steroids 14 have a weak inhibitory activity on 5α-reductase with IC50 values of: 280 (1), 2.6 (2), 1.6 (3) and 114?μM (4). The presence of Cl and Br atoms in the C-17 benzoyloxy group tends to increase the inhibitory potency of the compounds.

The binding efficiency of the synthesized steroids 14 to the androgen receptor of the prostate gland is also evaluated. All compounds form a complex with the receptor and this explains the weight reduction of the seminal vesicles in the animals treated with DHT plus steroids 14.  相似文献   

19.
Summary

Based on a revision of large recent collections housed at the Natural History Museum (London), Tel Aviv University and in the private collection of Yu. Verves and L. Khrokalo (Kyiv, Ukraine), new distributional data and an updated list with comments of 28 species of Middle Eastern Sarcophagidae of the subtribe Pterellina are presented. Seventeen of them are recorded for Israel, 11 for Egypt, four for Iran, two each for the Palestinian Authority, Saudi Arabia and Turkey, and one each for Jordan and the UAE. No data are known for the territories of Bahrain, Cyprus, Iraq, Kuwait, Lebanon, Oman, Qatar, Syria and Yemen. Twelve species new to science are described, including nine from Israel (Chaetapodacra montana n. sp., Eremasiomyia bicolor n. sp., E. deserta n. sp., E. fuscata n. sp., Protomiltogramma bidentata n. sp., P. serrata n. sp., Pterella hermonica n. sp., P. indigens n. sp., P. zefatica n. sp.), two from Egypt (Chaetapodacra griseola n. sp., Eremasiomyia alba n. sp.) and one from Saudi Arabia (Protomiltogramma arabica n. sp.). The male of Eremasiomyia nigra Rohdendorf, 1935 is described for the first time. One new combination of specific name is proposed ? Protomiltogramma immunita (Villeneuve, 1923), n. comb. Original keys for the identification of genera and species are proposed. An annotated list of all world genera and species and compiled data on larval habits of Pterellina are included.  相似文献   

20.
The intranasal route is one of the main routes of Mycobacterium leprae infection and there is paucity of information regarding the mode of spread of the pattern. The adherence of M.leprae to the nasal mucosa, its trapping within the sinuses of the head, and its fate after entry into the host was studied using mouse model. A comparison of the adherence profile of M. leprae and Mycobacterium tuberculosis showed that while larger numbers of M. tuberculosis were demonstrated within lungs, greater numbers of M.leprae were present within the sinuses of the head. Adherence of M.leprae to the nasal mucosa was dependent on surface integrity since opsonization and heat killing resulted in decreased numbers of M.leprae in the nasal sinuses and a greater amount entering the lungs. The adherence appeared to the independent of the viability of the bacilli, as similar numbers of formalin-fixed, rifampicin-treated and viable M.leprae entered the lungs in the initial stages. However the numbers of rifampicin-treated M. leprae in the nasal sinuses were 12-fold lower than the numbers of viable M.leprae. These results indicated that both viability and surface integrity were important in the entry of M.leprae and it’s consequent dissemination.  相似文献   

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