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71.
The study was aimed to research the growth inhibitory effects of two new bioactive peptides Temporin-Lb and Catesbeianin-1a from Rana catesbeiana on human lung cancer NCI-H446 cells, breast cancer MCF-7 cells and mice leukemia K562 cells, and provide the basis for selecting the new peptide antitumor drugs.The second structures of two bioactive peptides were tested by circular dichroism spectrum (CD), and the effects of the two new bioactive peptides on human lung cancer NCI-H446 cells, breast cancer MCF-7 cells and mice leukemia K562 cells were examined with MTS cytotoxicity assay.The circular dichroism spectrum results showed the secondary structure of Temporin-Lb was PPⅡ, and the secondary structure of Catesbeianin-1a was random coil.Using MTS cytotoxicity assay, it was found that given Catesbeianin-1a, the sharp of the three cancer cells above had little changed after culturing for 24 h, and the three cancer cells promoted normal.Given Temporin-Lb, the cell morphology of three cancer cells had changed after culturing for 24 h, the growth of the three cancer cells above had been inhibited, especially the bioactive peptide Temporin-Lb had a sharp antitumor effect to mice leukemia K562 cells between the concentration of 4 and 40 μmol/L.Bioactive peptide Catesbeianin-1a had no obvious effect on proliferation of the three cancer cells above.Bioactive peptide Temporin-Lb had a certain inhibitory effect to tumor cells. 相似文献
72.
Xiu-Wen Chen Chang-Wei Li Cheng-Bin Cui Wei Hua Tian-Jiao Zhu Qian-Qun Gu 《Marine drugs》2014,12(6):3116-3137
Nine new C9 polyketides, named aspiketolactonol (1), aspilactonols A–F (2–7), aspyronol (9) and epiaspinonediol (11), were isolated together with five known polyketides, (S)-2-(2′-hydroxyethyl)-4-methyl-γ-butyrolactone (8), dihydroaspyrone (10), aspinotriol A (12), aspinotriol B (13) and chaetoquadrin F (14), from the secondary metabolites of an Aspergillus sp. 16-02-1 that was isolated from a deep-sea sediment sample. Structures of the new compounds, including their absolute configurations, were determined by spectroscopic methods, especially the 2D NMR, circular dichroism (CD), Mo2-induced CD and Mosher’s 1H NMR analyses. Compound 8 was isolated from natural sources for the first time, and the possible biosynthetic pathways for 1–14 were also proposed and discussed. Compounds 1–14 inhibited human cancer cell lines, K562, HL-60, HeLa and BGC-823, to varying extents. 相似文献
73.
采用体外细胞培养检测自制羊软骨II型胶原蛋白(Type II collagen from sheep,CII)的细胞毒性,将材料与鸡胚成纤维细胞(Chick embryo fibroblast,CEF)共同培养,观察其对生长的影响,确定鸡胚成纤维细胞对羊软骨CII的最大安全浓度,以及在安全浓度范围内有效促进鸡胚成纤维细胞生长的浓度。结果显示,羊软骨CII对鸡胚成纤维细胞的最大安全浓度为400μg/mL,当羊软骨CII浓度在25μg/mL时,可以极显著的促进鸡胚成纤维细胞的生长。 相似文献
74.
用Balb/c雄小鼠的脾细胞和皮肤组织对同系雌小鼠脾脏作一次直接免疫和5次腹腔加强免疫,雌小鼠产生良好的免疫应答。其抗血清用未经免疫的雌小鼠脾细胞吸收后,经细胞毒性法检测,H-Y抗血清的效价可达1:1024;选择免疫应答最好的2只雌小鼠,取其脾细胞与NS-1骨髓瘤细胞进行融合,融合率100%,经3次有限稀释克隆后,取4只阳性最强的杂交瘤细胞制备腹水。取其中一株的腹水采用胚胎细胞毒法进行特异性鉴定,结果其对20个正常胚胎中的7个有杀伤溶解现象。4株细胞系分泌的抗体(腹水)以精子细胞毒法测定其效价分别为1:512、1:512、1:256和1:128。 相似文献
75.
Rohan A. Davis Lane V. Christensen Adam D. Richardson Rosana Moreira da Rocha Chris M. Ireland 《Marine drugs》2003,1(4):27-33
A new pyrrolopyrimidine alkaloid, rigidin E (1) and the known metabolites rigidin (2) and 1-methylherbipoline (3) have been isolated from a Papua New Guinea tunicate Eudistoma sp. A combination of spectroscopic data were used to determine the structures of these metabolites. 相似文献
76.
Three bianthraquinone derivatives from the mangrove endophytic fungus Alternaria sp. ZJ9-6B from the South China Sea 总被引:1,自引:0,他引:1
Three new bianthraquinone derivatives, alterporriol K (1), L (2) and M (3), along with six known compounds were obtained from extracts of the endophytic fungus Alternaria sp. ZJ9-6B, isolated from the mangrove Aegiceras corniculatum collected in the South China Sea. Their structures were elucidated by one- and two-dimensional NMR spectroscopy, MS data analysis and circular dichroism measurements. Compounds 1, 2 and 3 were first isolated alterporriols with a C-2–C-2′ linkage. The crystallographic data of tetrahydroaltersolanol B (7) was reported for the first time. In the primary bioassays, alterporriol K and L exhibited moderate cytotoxic activity towards MDA-MB-435 and MCF-7 cells with IC50 values ranging from 13.1 to 29.1 μM. 相似文献
77.
Hongwei Liu Yuri Mishima Takeshi Fujiwara Hiroshi Nagai Akira Kitazawa Yuji Mine Hisayoshi Kobayashi Xinsheng Yao Junko Yamada Taiko Oda Michio Namikoshi 《Marine drugs》2004,2(4):154-163
A new stereoisomer of an araguspongine/xestospongin alkaloid, named araguspongine M (1), has been isolated together with 12 known compounds, araguspongines B (2) and D (3), dopamine, three galactosyl diacylglycerols, 24-methyl cholesterol, 5,6-dihydrocholesterol, β-sitosterol, and three 5α,8α-epidioxy sterols (11–13), from the marine sponge Neopetrosia exigua (formerly Xestospongia exigua) collected in Palau. The structure of 1 was assigned on the basis of its spectral data analysis. This is the first report on the isolation of dopamine from a marine sponge. This compound may be produced by an endosymbiotic Synechococcus-like cyanobacterium. Compounds 1–3 and 11–13 showed cytotoxicity against HL-60 at IC50’s of 5.5, 5.5, 5.9, 22.4, 9.5, and 9.6 μM, respectively. The possible biosynthesis origin of the isolated metabolites is discussed. 相似文献
78.
Li S Tian X Niu S Zhang W Chen Y Zhang H Yang X Zhang W Li W Zhang S Ju J Zhang C 《Marine drugs》2011,9(8):1428-1439
Pseudonocardians A–C (2–4), three new diazaanthraquinone derivatives, along with a previously synthesized compound deoxynyboquinone (1), were produced by the strain SCSIO 01299, a marine actinomycete member of the genus Pseudonocardia, isolated from deep-sea sediment of the South China Sea. The structures of compounds 1–4 were determined by mass spectrometry and NMR experiments (1H, 13C, HSQC, and HMBC). The structure of compound 1, which was obtained for the first time from a natural source, was confirmed by X-ray analysis. Compounds 1–3 exhibited potent cytotoxic activities against three tumor cell lines of SF-268, MCF-7 and NCI-H460 with IC50 values between 0.01 and 0.21 μm, and also showed antibacterial activities on Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212 and Bacillus thuringensis SCSIO BT01, with MIC values of 1–4 μg mL−1. 相似文献
79.
Antibacterial and Cytotoxic New Napyradiomycins from the Marine-Derived Streptomyces sp. SCSIO 10428
Zhengchao Wu Sumei Li Jie Li Yuchan Chen Kumar Saurav Qingbo Zhang Haibo Zhang Wenjun Zhang Weimin Zhang Si Zhang Changsheng Zhang 《Marine drugs》2013,11(6):2113-2125
Three new napyradiomycins (1–3) were isolated from the culture broth of a marine-derived actinomycete strain SCSIO 10428, together with six known related analogues napyradiomycin A1 (4), 18-oxonapyradiomycin A1 (5), napyradiomycin B1 (6), napyradiomycin B3 (7), naphthomevalin (8), and napyradiomycin SR (9). The strain SCSIO 10428 was identified as a Streptomyces species by the sequence analysis of its 16S rRNA gene. The structures of new compounds 1–3, designated 4-dehydro-4a-dechloronapyradiomycin A1 (1), 3-dechloro-3-bromonapyradiomycin A1 (2), and 3-chloro-6,8-dihydroxy-8-α-lapachone (3), respectively, were elucidated by comparing their 1D and 2D NMR spectroscopic data with known congeners. None of the napyradiomycins 1–9 showed antioxidative activities. Napyradiomycins 1–8 displayed antibacterial activities against three Gram-positive bacteria Staphylococcus and Bacillus strains with MIC values ranging from 0.25 to 32 μg mL−1, with the exception that compound 3 had a MIC value of above 128 μg mL−1 against Staphylococcus aureus ATCC 29213. Napyradiomycins 2, 4, 6, and 7 exhibited moderate cytotoxicities against four human cancer cell lines SF-268, MCF-7, NCI-H460, and HepG-2 with IC50 values below 20 μM, while the IC50 values for other five napyradiomycins 1, 3, 5, 8 and 9 were above 20 μM. 相似文献
80.
Laurent Calcul Carrie Waterman Wai Sheung Ma Matthew D. Lebar Charles Harter Tina Mutka Lindsay Morton Patrick Maignan Alberto Van Olphen Dennis E. Kyle Lilian Vrijmoed Ka-Lai Pang Cedric Pearce Bill J. Baker 《Marine drugs》2013,11(12):5036-5050
We conducted a screening campaign to investigate fungi as a source for new antimalarial compounds. A subset of our fungal collection comprising Chinese mangrove endophytes provided over 5000 lipophilic extracts. We developed an accelerated discovery program based on small-scale cultivation for crude extract screening and a high-throughput malaria assay. Criteria for hits were developed and high priority hits were subjected to scale-up cultivation. Extracts from large scale cultivation were fractionated and these fractions subjected to both in vitro malaria and cytotoxicity screening. Criteria for advancing fractions to purification were developed, including the introduction of a selectivity index and by dereplication of known metabolites. From the Chinese mangrove endophytes, four new compounds (14–16, 18) were isolated including a new dimeric tetrahydroxanthone, dicerandrol D (14), which was found to display the most favorable bioactivity profile. 相似文献