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1.
目的 对从印度洋深海沉积物中分离到的一株深海来源的放线菌Streptomyces sp. SCSIO 03032进行次级代谢产物分析及其活性研究。方法 对深海来源放线菌Streptomyces sp. SCSIO 03032的发酵产物进行有机溶剂萃取,利用正、反向硅胶层析、硅胶柱层析、凝胶柱层析、薄层层析等分离手段进行纯化,通过ESI-MS、1H NMR、13C NMR分析及文献查阅鉴定化合物结构,并对化合物进行抗菌及抗氧化活性研究。结果 从深海来源放线菌Streptomyces sp. SCSIO 03032的发酵产物中分离得到3个芳酰胺类化合物,其结构分别鉴定为4-甲基苯-1, 3-二氨基甲酸甲酯(1)、2-甲基苯-1, 3-二氨基甲酸甲酯(2)、羰基亚氨基4-甲基-3, 1-亚苯基双[氨基甲酸]甲酯(3);活性结果显示三个化合物均无明显的抑菌活性或抗氧化活性。结论 得到了一株能够产生3个不同芳酰胺类化合物的深海链霉菌SCSIO 03032。  相似文献   

2.
目的 从海绵中分离培养放线菌,筛选具有抗青枯菌活性的菌株,分离鉴定活性代谢产物。方法 以来源于南海西沙永兴岛附近海域的海绵Leucetta chagosensis为实验材料,采用三种选择性分离培养基分离海绵的共附生放线菌,利用16S rRNA序列分析对各菌株进行种属鉴定。对各菌株的发酵提取物进行抗青枯菌活性筛选,采用硅胶柱层析、Sephadex LH-20凝胶柱层析和高效液相色谱法对筛选到的活性菌株的发酵产物进行分离、纯化,运用核磁共振(NMR)、质谱(MS)等手段,鉴定化合物的结构。采用微量稀释法测定化合物的最小抑菌浓度(MIC)。结果 分离培养海绵共附生放线菌16株,筛选得到一株具有较好抗青枯菌活性的菌株Streptomyces olivaceus LHW2444,并从该菌株的发酵产物中分离鉴定2个吡咯类化合物、1个苯并二恶茂类化合物、2个吡喃酮类化合物,分别为pyrrole-2-carboxamide(1)、pyrrole-2-carboxylic acid(2)、1,3-benzodioxole-2-one-4-carboxylamide(3)、germicidin B(4)、germicidin C(5),化合物1-5为首次从该种属放线菌分离得到。首次发现pyrrole-2-carboxylic acid对青枯菌具有较强抑制作用,MIC值为8 μg/mL。结论 海绵共附生菌Streptomyces olivaceus LHW2444是潜在的植物青枯病生防菌,pyrrole-2-carboxylic acid是抗青枯菌的活性代谢产物。  相似文献   

3.
目的 研究来源于海鞘的放线菌Streptomyces pratensis SCSIO LCY05产生的抑菌活性物质。 方法 采用硅胶柱色谱、中压制备色谱、半制备HPLC等方法对其发酵产物分离纯化,经HR-ESI-MS、NMR以及X-ray单晶衍射等方法确定化合物的结构;采用微量二倍稀释法对化合物进行抗菌活性评价。 结果 从发酵产物中分离鉴定了3个化合物:anthracimycin C(1)、anthracimycin(2)和anthracimycin B(3),结构得到X-ray单晶衍射的确证,其中化合物1为新化合物。经抗菌活性测定,化合物2和3对6株革兰氏阳性菌具有显著的抑制活性,最小抑菌浓度(MIC)值在0.0675-0.25 μg/mL之间,并首次发现化合物2和3对藤黄微球菌和模仿葡萄球菌生长抑制活性良好。 结论 海洋共附生微生物是天然活性物质的重要来源,从海鞘来源的S. pratensis SCSIO LCY05中分离获得具有抗菌活性的anthracimycin类化合物可作为良好的抗菌药物先导化合物。  相似文献   

4.
目的对从广西北海斜阳岛海域沉积物中分离的1株海洋源放线菌Streptomyces sp.SCSIO 10428进行次级代谢产物及活性研究。方法对海洋源放线菌Streptomyces sp.SCSIO 10428的发酵产物进行有机溶剂萃取,利用硅胶、凝胶柱层析等手段纯化次级代谢产物,通过波谱数据分析及文献比较对化合物进行结构鉴定,对化合物进行了抗菌、卤虫致死以及抗氧化活性评价。结果从海洋源放线菌Streptomyces sp.SCSIO10428发酵产物中分离得到3个生物碱类化合物,其结构分别鉴定为1-甲氧基吩嗪(1),1-羟基吩嗪(2),吩嗪-1-羧酸(3);活性结果显示化合物1~3对白色念珠...  相似文献   

5.
目的 对从南极潮间带沉积物样品中分离得到的两株具有抗菌活性的放线菌进行分类鉴定并进行次生代谢产物研究。方法 通过形态学分析及构建系统发育进化树鉴定菌株并对其发酵产物进行生物活性评价;利用硅胶、凝胶柱层析、semi-HPLC等色谱分离手段对两株菌的发酵产物进行分离纯化;采集所得化合物的质谱、NMR等数据并分析后鉴定其结构。结果 两株菌分别鉴定为Streptomyces sp. SCSIO 40061和Nocardiopsis sp. SCSIO KS107;从相应的发酵产物中分离得到两个二酮哌嗪类化合物,结构分别鉴定为:(3Z,6E)-1-N-甲基-3-苯亚甲基-6-(2-甲基-3-羟基丙烷)-2,5-二酮哌嗪 (1) 以及(3Z,6Z)-3-(4-对甲氧苯亚甲基)-6-(2-甲基丙烷)-2,5-二酮哌嗪 (2) 。结论 发现了两株能产二酮哌嗪类化合物的南极来源放线菌。  相似文献   

6.
摘 要:目的 对南海来源放线菌Streptomyces sp. HDN1844000的次级代谢产物进行研究。方法 在生物活性筛选和液相二级质谱(LC-MS/MS)分子网络化学信息学策略指导下,采用硅胶柱层析、Sephadex LH-20凝胶层析和高效液相色谱法(HPLC),对菌株提取物进行分离纯化,通过质谱(MS)、核磁共振谱(NMR)分析和与文献比对,阐明化合物结构,并对化合物的抑菌活性进行评价。结果 从放线菌Streptomyces sp. HDN1844000的次级代谢产物中分离出1个新的spirotetronate类抗生素lobophorin N(1)和1个已知的类似物lobophorin A(2)。化合物1是1个新的lobophorin衍生物,其带有1个含3-氨基的D-kijanose变体并且在C-32处有1个甲基。生物活性筛选结果表明化合物1对蜡状芽孢杆菌、变形杆菌、草分枝杆菌和副溶血弧菌具有良好的抑菌活性,最低抑菌浓度(MIC)值为0.10~0.39 μmol/L。  相似文献   

7.
目的 寻找海洋放线菌来源的十字孢碱产生菌,筛选获得目标菌株,分离鉴定其具有吲哚咔唑母核的产物。方法 以十字孢碱在λmax290 nm附近尖锐的特征紫外吸收为标准,利用HPLC-UV对不同来源的海洋放线菌的发酵提取物进行定向筛选,筛选出十字孢碱产生菌,利用16S rRNA序列对筛选得到的菌株进行种属鉴定。通过比较各产生菌的十字孢碱类产物的丰度,选择能够产生更多该类化合物的菌株进行规模化发酵,并采用硅胶柱层析、Toyopearl HW-40F凝胶柱层析、高效液相色谱(HPLC)等方法对其发酵提取物进行分离、纯化,运用质谱(MS)、核磁共振(NMR)等技术鉴定化合物的结构。采用CCK-8法测定化合物的细胞毒活性。 结果 从42株放线菌中筛选出12株十字孢碱的产生菌,其中Streptomyces sp. OUCMDZ-5380的产物最为丰富,从该菌株发酵提取物中分离鉴定了3个吲哚咔唑类化合物,分别为K252c (1)、十字孢碱 (2)和4"-O-去甲基十字孢碱 (3)。细胞毒活性测试表明,化合物3对12株肿瘤细胞株的IC50值达到纳摩尔、介于0.0003–0.623 μM之间。 结论 筛选得到12株主产十字孢碱的海洋放线菌,从OUCMDZ-5380的发酵产物中鉴定了3个吲哚咔唑类化合物,化合物3具有广谱的肿瘤细胞毒活性(半数抑制浓度IC50为0.0003–0.623 μM.)和对内部串联复制突变的人急性髓细胞性白血病细胞MV4-11的选择性(相对于人正常细胞株L-02和其它人肿瘤细胞株的选择指数分别为1120和50–2080)。  相似文献   

8.
目的: 分离鉴定深海来源放线菌Streptomyces sp. OUCMDZ-4112的活性天然产物。方法:采用硅胶色谱,凝胶色谱及高效液相色谱(HPLC)等常规分离纯化手段对菌株的天然产物进行分离、纯化;运用核磁共振、CD、紫外、红外和旋光等方法鉴定所得化合物的结构;采用MTT法和CCK-8法评价化合物的细胞毒活性、对硝基苯基-α-吡喃葡萄糖苷(PNPG)法评价化合物的α-糖苷酶抑制活性。结果:从深海沉积物来源的链霉菌OUCMDZ-4112的发酵产物中分离鉴定了2个新的吡咯生物碱:S(+)-2-甲氧基-4-氧亚基-4-(2-吡咯基)丁酰胺(1)和R(–)-2-甲氧基-4-氧亚基-4-(2-吡咯基)丁酰胺(2)、以及2个已知的灵菌红素(PGs):streptoriubin B (3) 和undecylprodigiosin (4)。化合物3和4对K562肿瘤细胞株具有强细胞毒活性,IC50分别为0.60 μmol/L和0.01 μmol/L(阿霉素的 IC50 为0.43 μmol/L);同时外消旋1/2和化合物3、4具有α-糖苷酶抑制活性,IC50值分别为2.61、0.082和0.92 mmol/L(阿卡波糖的IC50为1.12 mmol/L)。结论:本文首次报道了PGs类化合物 3和 4的α-糖苷酶抑制活性;作为中间产物,新化合物1和 2的分离鉴定,证明了文献中PGs的生合成途径。  相似文献   

9.
目的 研究1株珊瑚来源的共附生链霉菌菌株Streptomyces sp. rssa2的次生代谢产物及其抗菌活性。方法 采用正相硅胶柱色谱、ODS反相硅胶柱色谱、Sephadex LH-20凝胶柱色谱以及半制备高效液相色谱(HPLC)等手段对rssa2的发酵产物进行分离纯化,通过核磁、质谱数据并结合文献数据鉴定化合物结构;通过滤纸片法和稀释法对化合物的抗菌活性进行测定。结果 从海洋链霉菌Streptomyces sp. rssa2的液体麦芽提取物培养基发酵产物中分离得到3个主要成分,其结构分别鉴定为大环内酯类化合物aldgamycin G(1)、aldgamycin E(2)、swalpamycin(3)。抗菌活性测试结果显示,化合物1~3均对溶藻弧菌(Vibrio alginolyticus)的生长具有弱抑制活性。结论 化合物1~3均为首次从珊瑚共附生链霉菌中分离获得,并且发现它们具有一定程度的抗菌活性,具有潜在的研究价值。  相似文献   

10.
摘 要:目的 对一株来源于南海沉积物的放线菌Streptomyces sp. SCSIO BEMM34进行菌种鉴定及次级代谢产物研究。方法 通过16S rDNA序列分析并构建系统发育进化树来鉴定菌株,利用硅胶、凝胶层析,半制备高效液相分离等手段对海洋放线菌SCSIO BEMM34的发酵产物进行分离纯化,通过波谱数据分析及文献比对的方法对分离纯化得到的化合物进行结构鉴定,采用滤纸片法进行抗菌活性测试。结果 从一株海洋来源放线菌中分离得到2个戊二酰亚胺类化合物1和2,以及一个酚酸类化合物3。抗菌活性测试结果表明,化合物1-3都没有明显的抑菌活性。  相似文献   

11.
12.
Depression and anxiety frequently coexist in patients with substance use disorders. This clinically-oriented article examiens the relationship between these conditions and emphasizes data showing that substances of abuse can cause signs and symptoms of both depression and anxiety. These substance-related syndromes appear to have a different course and prognosis than uncomplicated, independent anxiety and major depressive disorders, and clinicians should consider the role of alcohol and other drugs in all patients presenting with these complaints. The authors will also outline an approach for diagnosing and managing patients with the combination of a substance use and depressive or anxiety disorder.  相似文献   

13.
The synthesis of gaultherin (1) and its analogs was carried out to provide 11 glycosides under phase-transfer catalytic conditions. The activities of all synthesized compounds were evaluated by nitric oxide production inhibitory assay in vitro. Methyl 2-O-(4-O-β-d-galactopyranosyl)-β-d-glucopyranosylbenzoate (5f) showed significantly anti-nociceptive and anti-inflammatory effects by the evaluation in vivo. Structure–activity relationships within these compounds were discussed.  相似文献   

14.
Nestorov I 《Toxicology letters》2001,120(1-3):411-420
Two important methodological issues within the framework of the variability and uncertainty analysis of toxicokinetic and pharmacokinetic systems are discussed: (i) modelling and simulation of the existing physiologic variability in a population; and (ii) modelling and simulation of variability and uncertainty when there is insufficient or not well defined (e.g. small sample, semiquantitative, qualitative and vague) information available. Physiologically based pharmacokinetic models are especially suited for separating and characterising the physiologic variability from the overall variability and uncertainty in the system. Monte Carlo sampling should draw from multivariate distributions, which reflect all levels of existing dependencies in the intact organism. The population characteristics should be taken into account. A fuzzy simulation approach is proposed to model variability and uncertainty when there is semiquantitative, qualitative and vague information about the model parameters and their statistical distributions cannot be defined reliably.  相似文献   

15.
骨质疏松是一种全身性骨骼疾病,导致骨折风险增加。成人的骨量通过破骨细胞的骨吸收和成骨细胞的骨形成作用来维持动态平衡,治疗骨质疏松症的理想策略是抑制破骨细胞的骨吸收和/或增强成骨细胞的骨形成功能。目前针对保护成骨细胞及增强其功能的骨质疏松疗法相对较少。因此,本文针对成骨细胞相关功能蛋白、各种细胞损伤机制(内质网应激、氧化应激、机械过载、微小RNA和长链非编码RNA的影响等)及骨质疏松的治疗与预防作一综述,以期为针对增强成骨细胞功能的骨质疏松治疗策略提供新思路。  相似文献   

16.
益生菌广泛存在于自然界中,通过维持宿主体内菌群平衡、影响肠屏障功能和调节免疫应答等作用,提高宿主健康水平,被公认为"肠道健康卫士".一些益生菌可以增强机体的免疫功能,抑制致癌物质,影响肿瘤细胞的基因表达,对肿瘤具有拮抗作用.大量研究表明,益生菌在未来的肿瘤防治中有很好的应用和发展前景.  相似文献   

17.
[6,7-3H] Estrone (E) and [6,7-3H]estradiol-17 (E2) have been synthesized by reduction of 6-dehydroestrone and 6-dehydroestradiol with tritium gas. Tritiated E and E2 were administered by oral gavage to female rats and to male and female hamsters on a dose level of about 300 g/kg (54 mCi/kg). After 8 h, the liver was excised from the rats; liver and kidneys were taken from the hamsters. DNA was purified either directly from an organ homogenate or via chromatin. The radioactivity in the DNA was expressed in the units of the Covalent Binding Index, CBI = (mol chemical bound per mol DNA-P)/(mmol chemical administered per kg b.w.). Rat liver DNA isolated via chromatin exhibited the very low values of 0.08 and 0.09 for E and E2, respectively. The respective figures in hamster liver were 0.08 and 0.11 in females and 0.21 and 0.18 in the males. DNA isolated from the kidney revealed a detectable radioactivity only in the female, with values of 0.03 and 0.05 for E and E2, respectively. The values for male hamster kidney were < 0.01 for both hormones. The minute radioactivity detectable in the DNA samples does not represent covalent binding to DNA, however, as indicated by two sets of control experiments. (A) Analysis by HPLC of the nucleosides prepared by enzyme digest of liver DNA isolated directly or via chromatin did not reveal any consistent peak which could have been attributed to a nucleoside-steroid adduct. (B) All DNA radioactivity could be due to protein contaminations, because the specific activity of chromatin protein was determined to be more than 3,000 times higher than of DNA. The high affinity of the hormone to protein was also demonstrated by in vitro incubations, where it could be shown that the specific activity of DNA and protein was essentially proportional to the concentration of radiolabelled hormone in the organ homogenate, regardless of whether the animal was treated or whether the hormone was added in vitro to the homogenate.Carcinogens acting by covalent DNA binding can be classified according to potency on the basis of the Covalent Binding Index. Values of 103–104 have been found for potent, 102 for moderate, and 1–10 for weak carcinogens. Since estrone is moderately carcinogenic for the kidney of the male hamster, a CBI of about 100 would be expected. The actually measured limit of detection of 0.01 places covalent DNA binding among the highly unlikely mechanisms of action. Similar considerations can be made for the liver where any true covalent DNA binding must be below a level of 0.01. It is concluded that an observable tumor induction by estrone or estradiol is unlikely to be due to DNA binding.Paper presented at the Satellite Symposium of the European Society of Toxicology, Rome, March 29, 1983  相似文献   

18.
The effects of the d and l isomers of amphetamine on self-stimulation responding were tested following acute and chronic administration. Tolerance and post-drug depression of responding occurred in tests with both isomers, indicating no role for p-hydroxynorephedrine (PHN) which is one of the metabolites of d-amphetamine. In the second experiment, d-amphetamine, methylphenidate and cocaine all produced quantitatively and qualitatively similar effects on self-stimulation responding following acute administration. Following chronic administration of d-amphetamine, animals showed tolerance to all three drugs, indicating cross-tolerance among them. These data are consistent with an hypothesis that tolerance and post-drug depression following chronic amphetamine treatment are the result of decreases in postsynaptic receptor sensitivity, which would lead to a decreased effectiveness of all three drugs, regardless of their pre-synaptic mechanisms.  相似文献   

19.
Rationale  Two pharmacotherapies are approved for treating alcohol craving (acamprosate and naltrexone), but both have shown mixed findings in animals and humans. Objectives  The present experiments utilized a “reinforcer blocking” approach (i.e., rats were able to consume ethanol during treatment) to better understand the efficacy of these treatments for ethanol seeking and drinking using ethanol-dependent and nondependent rats. Materials and methods  In “nondependent” experiments, drugs (acamprosate 50, 100, and 200 mg/kg; naltrexone 0.1, 0.3, and 1.0 mg/kg) were administered over 3-week periods prior to operant sessions with a low response requirement to gain access to reinforcers for 20 min. For “dependent” experiments, rats were made dependent in vapor/inhalation chambers. Results  Acamprosate and naltrexone had similar effects on intake in nondependent and dependent rats; neither drug was selective for ethanol over sucrose drinking. In nondependent animals, naltrexone was more efficacious at more doses than acamprosate, and acamprosate’s effects were limited to a dose that also had adverse effects on body weight. Both pharmacotherapies showed more selectivity when examining reinforcer seeking. In nondependent rats, acamprosate and naltrexone had response-attenuating effects in ethanol, but not sucrose, groups. In dependent animals, acamprosate had selective effects limited to a decrease in sucrose seeking. Naltrexone, however, selectively decreased ethanol-seeking in nondependent rats. Conclusions  The naltrexone-induced decreases in seeking suggested a change in incentive motivation which was selective for ethanol in nondependent rats. The “nondependent” paradigm may model early stages of “problem drinking” in humans, and the findings suggest that naltrexone could be a good intervention for this level of alcohol abuse and relapse prevention.  相似文献   

20.
Catheters, urethral and ureteral stents and other urological implants are frequently affected by encrustration and infection due to their permanent contact with urine. Indwelling urinary catheters provide a haven for microorganisms and thus require extensive monitoring. Several surface modification techniques have been proposed to improve the performance of devices including the immobilization of biomolecules, the incorporation of hydrophilic grafts to reduce protein adsorption, the creation of hydrophobic surfaces, the creation of microdomains to regulate cellular and protein adhesion, new polymers and antimicrobial coatings. Physico-chemical explanation to elucidate the mechanism of such encrustation or infection inhibiting materials is still not available. Our series of experiments showed a marked decrease of silver-activity in biological fluids which corresponds with the controversial clinical results obtained with silver coated urinary catheters. Rifampicin/minocycline coated catheters had very low activity against Gram-negative rods, enterococci and Candida spp., the main causing organisms of urinary catheter infection. Surface engineered materials and antimicrobial drug delivery systems will be the next generation of sophisticated urinary catheters and stents, if both efficacy as well as efficiency has been proved clinically.  相似文献   

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