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1.
A new isobenzofuran derivative (1) was isolated from the marine Streptomyces sp. W007 and its structure was determined through extensive spectroscopic analyses, including 1D-NMR, 2D-NMR, and ESI-MS. The absolute configuration of compound 1 was determined by a combination of experimental analyses and comparison with reported data, including biogenetic reasoning, J-coupling analysis, NOESY, and 1H-1HCOSY. Compound 1 exhibited no cytotoxicity against human cells of gastric cancer BGC-823, lung cancer A549, and breast cancer MCF7.  相似文献   

2.
Four bromophenols were isolated from the extract of marine red alga, Rhodomela confervoides by column chromatography and HPLC methods. By means of spectroscopic methods including IR, MS, 1D, and 2D-NMR techniques, their structures were elucidated as (1) 3-bromo-4,5-dihydroxy benzoic acid methyl ester; (2) his (2,3-dibromo-4,5-dihydroxybenzyl) ether; (3) 3,4-dibromo-5-(methoxymethyl)-1,2-benzenediol and (4)3-bromo-4,5-dihydroxy-benzaldehyde. Compound 1 was first isolated from the algae in nature, and 1, 4 were found to have selective cytotoxic activities against KB, Bel 7402 and A549 cells, 2 showed powerful antibacterial activities against Staphylococcus aurens and Pseudomonas aeruginosa.  相似文献   

3.
Four bromophenols were isolated from the extract of marine red alga,Rhodomela confervoides by column chromatography and HPLC methods. By means of spectroscopic methods inclding IR, MS, 1D, and 2D-NMR techniques, their structures were elucidated as (1) 3-bromo-4,5-dihydroxy benzoic acid methyl ester; (2) bis (2,3-dibromo-4,5-dihydroxybenzyl) ether; (3) 3,4-dibromo-5-(methoxymethyl)-1,2-benzenediol and (4) 3-bromo-4,5-dihydroxy-benzaldehyde. Compound 1 was first isolated from the algae in nature, and 1, 4 were found to have selective cytotoxic activities against KB, Bel 7402 and A549 cells, 2 showed powerful antibacterial activities againstStaphylococcus aurens andPseudomonas aeruginosa. Supported by National “863” Program (No. 2004AA625030, 2001AA620503), Quingdao marine sciences project (No. 04-2-NN-26) and Key Knowledge Innovative Project of the Chinese Academy of Sciences (KZCX3-SW-215).  相似文献   

4.
Two phenylquinolinones, including one new compound (1) and a previously isolated compound (2), were isolated from the ethyl acetate extracts of the fungus Aspergillus versicolor Y31-2, which was obtained from seawater samples collected from the Indian Ocean. The structures of these compounds were established by spectroscopic analyses. 4-(3-Hydroxyphenyl)-3-methoxyquinolin-2(1H)-one (1) exhibited moderate cytotoxicity against MCF-7 (human breast carcinoma cell line) and SMMC-7721 (human liver cancer cell line) cells with IC50 values of 16.6 and 18.2 μmol/L, respectively. To the best of our knowledge, this study represents the first reported account of the isolation of compounds 1 and 2 as the secondary metabolites of the seawater derived fungus Aspergillus versicolor from the Indian Ocean.  相似文献   

5.
The effects of cadmium(Cd)on metal accumulation,microelements contents,and antioxidant responses in Hexagram-mos otakii were studied.The fish were exposed to 0.2,2.5,or 10μg L?1 Cd for 12 or 24 days.Then,the concentration of Cd and mi-croelements(Ca,Fe,Zn,and Se)were determined in the liver and kidney.Moreover,the activities of antioxidant enzymes including superoxide dismutase(SOD),catalase(CAT),and glutathione-S-transferase(GST),and the content of malondialdehyde(MDA)in the liver and kidney were also measured.A continuous accumulation of Cd was observed throughout the experimental period.Cd accumulation was higher in liver than that in the kidney,while Ca and Fe contents were lower in liver than those in the kidney.Cd exposure resulted in a decrease of Ca and Fe concentrations in the kidney,while there was no effect on the liver.Zn and Se remained unaffected with exposure to Cd.Cd exposure induced severe oxidative stress in H.otakii,as indicated by significant induction of the activities of SOD,CAT,and GST,and a simultaneous increase of MDA content.These data show that antioxidant enzymes and mi-croelements contents can be used as potential biomarkers to monitor environmental health in fish.  相似文献   

6.
Sea surface temperature (SST) variation in the Subei coastal waters, East China, which is important for the ecological environment of the Yellow Sea where Enteromorphaprolifera blooms frequently, is affected by the East Asian winter monsoon (EAWM), El Nifio-Southem Oscillation (ENSO), and Pacific Decadal Oscillation (PDO). In this study, correlations between climatic events and SST anomalies (SSTA) around the Subei (North Jiangsu Province, East China) Coast from 1981-2012 are analyzed, using empirical orthogonal function (EOF) and correlation analyses. First, a key region was determined by EOF analysis to represent the Subei coastal waters. Then, coherency analyses were performed on this key region. According to the correlation analysis, the EAWM index has a positive correlation with the spring and summer SSTA of the key region. Furthermore, the Nifio3.4 index is negatively correlated with the spring and summer SSTA of the key region 1 year ahead, and the PDO has significant negative coherency with spring SSTA and negative coherency with summer SSTA in the key region 1 year ahead. Overall, PDO exhibits the most significant impact on SSTA of the key region. In the key region, all these factors are correlated more significantly with SSTA in spring than in summer. This suggests that outbreaks ofEnteromorpha prolifera in the Yellow Sea are affected by global climatic changes, especially the PDO.  相似文献   

7.
A new ketosteroid, along with six known steroids, was isolated from the ethanolic extracts of red alga Acanthophora spicifera (Vahl.) Boergesen. The structures, identified using chemical and spectroscopic methods including 2D NMR, were: (1) 22-hydroxy-5α-cholest-3,6-dione, (2) 6-hydroxycholest-4-ene-3-one, (3) cholest-4-ene-3,6-dione, (4) cholest-5-ene-3β-ol, (5) 5α-cholestane-3,6-dione, (6) β-Sitosterol and (7) Saringosterol. The MTT method was used to test the cytotoxicity of the compounds against the human cancer cell lines, HCT-8, Bel-7402, BGC-823, A549 and HELA. Compounds 1, 2, 3 and 5 showed moderate cytotoxic activity against human cancer cell lines.  相似文献   

8.
The effects of Bacillus subtilis 2-1 from the intestine of healthy sea cucumber on the growth, digestive enzyme activities and intestinal microbiota of juvenile sea cucumber(Apostichopus japonicus) were determined in the present study. Sea cucumber was fed with Sargassum thunbergii powder supplemented with B. subtilis 2-1 at different concentrations varying among 0(control), 10~5, 10~7, and 10~9 CFU g~(-1) for 8 weeks. Results showed that the growth performance and intestinal amylase and trypsin activities were significantly increased by dietary B. subtilis 2-1 at 10~9 CFU g~(-1)(P 0.05). However, dietary B. subtilis 2-1 had no significant influence on the lipase activity in sea cucumber(P 0.05). The polymerase chain reaction denaturing gradient gel electrophoresis and 16S rRNA gene sequencing analysis indicated that dietary B. subtilis 2-1 at 105 and 107 CFU g~(-1) inhibited most of the Proteobacteria including those in genus Vibrio. Dietary B. subtilis 2-1 at 10~9 CFU g~(-1) not only decreased the abundance and species of genus Vibrio, but also increased the intensity of genera Psychrobacter and Bacillus. A specific dosage of dietary B. subtilis 2-1 could increase the growth and modulate the intestinal microbiota of sea cucumber; thus it might be a novel probiotic for keeping the health of sea cucumber.  相似文献   

9.
1 IntroductionAnicecoreobtainedfrom polarglaciersoricesheetsisoneofthemostimportantarchivestoreconstructpaleoclimaticandpaleoatmosphericcondition .Informationonpale o environmentcanbeextractedfromicecoresaschemicaland/orphysicalsignals.Amongthechemicalsignals,heavymetalsarenotedassignalsofterrestrialenvironmentalchangeandanthropogenicpollution (e.g .Murozumietal.1 969;NgandPatterson 1 981 ;Hongetal.1 994) .SinceconcentrationsofmostofthemetalsinpolarsnowincentralGreen landareatorbelowthepptl…  相似文献   

10.
广西大新下雷锰矿是在1958年大办钢铁时期由当地村干部赵承祥误为铁矿石而发现的,同年10月经地质人员颜锦生等到现场检查确认为锰矿石。从1958年11月起至1990年底止,历经南宁专署地质局903队,广西地质局424队、广西第二地质队、广西第四地质队断续地进行找矿勘查工作,探明了锰矿石总储量13378万吨,其中放电性锰矿石556万吨,氧化锰矿石1210万吨,碳酸锰矿石11612万吨,证实为一特大型锰矿床。因此,广西第二地质队于1980年被地质部授予功勋队称号,而广西第四地质队于1985年荣获全国地矿系统找矿成果一等奖。现在已建成广西大新锰矿,一座新兴的矿山城镇耸立在桂西南山谷中。  相似文献   

11.
We previously isolated a natural product, namely guaiazulene-2,9-dione showing strong antibacterial activity against Vibrio anguillarum, from a gorgonian Muriceides collaris collected in South China Sea. In this experiment, guaiazulene-2,9-dione was quantitatively synthesized with an optimized one-step bromine oxidation method using guaiazulene as the raw material. The key reaction condition including reaction time and temperature, drop rate of bromine, concentration of aqueous THF solution, respective molar ratio of guaiazulene to bromine and acetic acid, and concentration of guaiazulene in aqueous THF solution, were investigated individually at five levels each for optimization. Combined with the verification test to show the absolute yield of each optimization step, the final optimal condition was determined as: when a solution of 0.025 mmol m L-1 guaiazulene in 80% aqueous THF was treated with four volumes of bromine at a drop rate of 0.1 m L min-1 and four volumes of acetic acid at-5℃ for three hours, the yield of guaiazulene-2,9-dione was 23.72%. This was the first report concerning optimized one-step synthesis to provide a convenient method for the large preparation of guaiazulene-2,9-dione.  相似文献   

12.
根据草鱼呼肠孤病毒(Grass Carp Reovirus,GCRV)的vp5基因设计特异性引物,并扩增其开放阅读框序列(open reading frame,ORF),然后连接至pGBKT7载体上构建酵母双杂交诱饵载体pGBKT7-vp5,转化至酵母菌Y2HGold,并进行PCR鉴定以及自激活性和毒性检测。PCR、酶切以及测序表明,pGBKT7-vp5重组诱饵载体构建成功。自激活性和毒性检测显示,阳性重组菌株pGBKT7-vp5/Y2HGold和阴性对照菌株pGBKT7/Y2HGold在SD/-Trp平板上出现大小相一致的乳白色菌落,且在SD/-Trp/X-α-Gel、SD/-Trp/AbA+/X-α-Gel平板上生长出蓝色菌落,而在SD/-Trp/-Ade/-His无菌落出现。表明重组菌株pGBKT7-vp5/Y2HGold表达的融合蛋白激活了报告基因AUR1-C和MEL1,没有激活报告基因ADE2和HIS3并且对宿主菌无毒性。该重组诱饵载体可用于酵母双杂交系统进一步筛选cDNA文库中与其相互作用的蛋白。  相似文献   

13.
The Chinese shrimp Penaeus (Fenneropaeneus) chinensis is an important species in marine fishery and aquaculture in China. A female Chinese shrimp Penaeus (Fenneropaeneus) chinensis was captured from west coast of the Korean peninsula and mated with a “Yellow Sea No. 1” male to produce the first filial generation (F1) 100 F2 full-sib progeny from brother-sister crosses between F1 families was used for the mapping study. A genetic linkage map of the Chinese shrimp was constructed, based on 354 markers, including 300 amplified fragment length polymorphism (AFLP) markers, 42 microsatellite (SSR) markers, and 12 randomly amplified polymorphism (RAPD) markers. Forty-seven linkage groups (LGs) were identified. The total map length was 4 580.5 cM, with an average spacing of 11.3 cM, covering 75.8% of the estimated genome size. The construction of this genetic linkage map was part of a genetic breeding program. This linkage map will contribute to the discovery of genes and quantitative trait loci (QTLs) in Chinese shrimp.  相似文献   

14.
选取1 日龄乌鬃鹅300 只,随机分成5 组,对照组(A)用基础饲粮饲养,实验组B~E 组分别在基础饲粮中添加质量分数1%(B 组)、2%(C 组)、3%(D 组)、4%(E 组)的螺旋藻,实验期63 d.结果表明:与对照组相比,添加螺旋藻对乌鬃鹅的屠宰率、半净膛率、腹脂率和肌肉灰分无显著影响(P〉0.05),对其它生长指标和全净膛率均有显著性影响(P〈0.05),其中2%C 组和3% D 组的料重比显著下降(P〈0.05), E 组全净膛率显著提高(P〈0.05);肌肉的粗蛋白质(CP)含量E〉D〉C〉B〉A,粗脂肪(EE)含量E〉A〉B〉C〉D;所测得的17 种氨基酸中,包括含有人体必需的7 种氨基酸(EAA)和2 种半必需氨基酸(HEAA);氨基酸评分(AAS)和化学评分(CS)最高的是赖氨酸(Lys),实验组的必需氨基酸指数(EAAI)均比对照组有所提高.添加2%~3%(w)的螺旋藻对生长性能有显著差异(P〈0.05),对粗脂肪、粗蛋白的含量有所改善;从肌肉EAAI 来看,添加螺旋藻后的肌肉蛋白质品质优于不添加螺旋藻的对照组.建议饲粮中螺旋藻的添加量为质量分数2%.  相似文献   

15.
1Introduction Red tides occur in recorded history,but in recentyears there is a global increase in the number of theseevents due to coastal pollution and other unclear fac-tors.Some kinds of red tides cause mass deaths of cul-tured animals and thus cause heavy economic losses forcoastwise mariculture(Nakanishi et al.,1996;Changet al.,1998;Zhu et al.,1998;Tada et al.,2001).The investigation on red tide control,however,rem-ains insufficient(Burkholder,1998;Edwards and Clark,1999).Although man…  相似文献   

16.
以勒氏笛鲷(Lutjanus russellii)基因组DNA为模板,采用同源克隆的方法,获得2 887 bp的肌肉生长抑制素(myostatin,MSTN)基因组序列,该MSTN序列具有3个外显子和2个内含子,包括101 bp的5′-UTR、385bp的外显子1、354 bp的内含子1、370 bp的外显子2、761 bp的内含子2、381 bp的外显子3和1 932 bp的3′-UTR。整个开放阅读框编码了378个氨基酸,前面的22个氨基酸为信号肽,具有9个保守的半胱氨基酸及一个RVRR的蛋白酶解加工位点。氨基酸序列分析发现,该基因编码的蛋白质与其他鱼类的I型同源性较高,与其他鱼类的2型MSTN同源性较低,且与鲈形目的同源性最高,与鲤形目的同源性较低,与人、鼠和鸡的同源性最低。采用邻接法(Neighbor-Joining)构建的MSTN的系统发育树表明,勒氏笛鲷MSTN与鲈形目鱼类的狼鲈属亲缘关系较近,且与鱼类的MSTN-1聚为1支。这表明该基因属于Ⅰ型MSTN基因。  相似文献   

17.
The Java Island, Indonesia with abundant amount of pyroclastic deposits is located in the very active and dynamic Pacific Ring of Fires. Studying the geochemical weathering indices of these pyroclastic deposits is important to get a clear picture about weathering profiles on deposits resulting from the eruption of Mt. Merapi. Immediately after the first phase of the eruption (March to June 2006), moist and leached pyroclastic deposits were collected. These pyroclastic deposits were found to be composed of volcanic glass, plagioclase feldspar in various propoitions, orthopyroxene, clinopyroxene, olivine, amphibole and titanomagnetite. The total elemental composition of the bulk samples (including trace elements and heavy metals) was determined by wet chemical methods and X-ray fluorescence (XRF) analyses. Weathering of the pyroelastic deposits was studied using various weathering indices. The Ruxton ratio, weathering index of Parker, Vought resudual index and chemical index of weathering of moist pyroclastic deposits were lower than those of the leached samples, but the alteration indices (chemical and plagioclase) were slightly higher in the moist compared to the leached pyroelastic deposits.  相似文献   

18.
Gene sequence-based genealogies of scuticociliates are different from those produced by morphological analyses. For this reason, 11 representative scuticociliates and two ambiguously related genera were chosen to test the ability of combined phylogenetic analyses using both gene sequences and morphological/morphogenetic characteristics. Analyses of both the SSrRNA gene sequences and the combined datasets revealed a consistent branching pattern. While the terminal branches and the order level relationships were generally well resolved, the family level relationships remain unresolved. However, two other trees based on ITS1-5.8S-ITS2 region sequences and morphological/morphogenetic characters showed limited information, due to a lack of informative sites in these two datasets. Our data suggest, however, that the combined analysis of morphological/morphogenetic characters and gene sequences did produce some changes to the phylogenetic estimates of this group.  相似文献   

19.
According to palaeoclimatic and modern instrumental data, numerous studies have indicated that the Arctic climate has undergone a significant warming during the past 100 years, and this may lead to significant impact on the fragile lake ecosystem. In this study, we collected a lake sediment core from the Ny-(A)lesund of Svalbard and determined the concentrations of four pigments including chlorophyll derivatives, total carotenoids, oscillaxanthin and myxoxanthophyll in the sediments. Combined with other physical and chemical proxies such as calcium carbonate, total organic carbon, biogenic silicon etc., we have reconstructed the historical changes of lacustrine primary productivity in Ny-(A)lesund, especially for the past 100 years. The results showed that during the period of Little Ice Age (LIA), the climate was unfavorable for the growth of the lake algae, and thus the lacustrine productivity declined. This result was supported by the relatively low contents of pigment and biogenic silica in the sediments. In contrast, the contents of total organic carbon (TOC) and sediment pigments increased significantly in the upper 5 cm (~1890AD), reflecting the rapid growth of the lake algae, thus the great increase of lacustrine primary productivity, corresponding to the warming climate after LIA. However, the biogenic silica in the upper sediments still had a relatively low level, and this might be related to the growth competition with other algae species. Over the past 100 years, the ratio of Osc/Myx in the sediments decreased continuously, indicative of durative increase of myxoxanthophyll in blue-green algal pigments, and this might imply that the human activity had enhanced the nutrition level of the lake in the Arctic region.  相似文献   

20.
The study presents the results of U-Pb dating of zircons and whole-rock geochemical analyses of a syenogranite located in the western Niubiziliang area,China with the aim of determining its formation time,petrogenesis and the regional tectonic setting. Zircons within the syenogranite are euhedral-subhedral and display rhythmic growth zoning,indicating a magmatic origin. Zircon U-Pb data obtained by LA-ICP-MS indicate the syenogranite formed in the Late Permian (260.7±1.5 Ma). The w(SiO_2) of syenogranites is 70.82%--73.59%,w(Al_2O_3) is 13.49%--14.82%,and w(Na_2O + K_2O) is 7.85%--8.52%,and yield K_2O/Na_2O ratios of 1.06--1.26. Therefore,the syenogranites belong to the high-K calc-alkaline and metaluminous (A/CNK 1,A/NK 1) series which display I-type granites similarly. The syenogranites also show the geochemical characteristics of volcanic arc rocks,being enriched in large-ion lithophile elements (LILEs; K,Rb) and light rare-earth elements (LREEs; La,Ce,Sm,Nd),but depleted in high field strength elements( HFSEs; Ta,Nb,P,Ti). On the whole,trace element ratios are close to the mean of the Earth's crust,indicating a lowercrust magma source. The low Sr (161--214) ×10~(-6) and Yb (1.08--1.80)×10~(-6) concentrations indicate that plagioclase and hornblende are residual mineral phases in the source. The regional geology and whole-rock geochemistry suggest that the formation of the syenogranites was related to subduction of the Zongwulong Ocean crust,and the north margin of Qaidam Block during the Late Permian was in an active continental margin tectonic setting.  相似文献   

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