首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 109 毫秒
1.
本文合成了尚未见报道的L—亮氨酸Schiff碱的锌(Ⅱ)配合物,并进行了性质表征和抑菌活性实验。  相似文献   

2.
苏芸金杆菌85-10-6(S)发酵培养基的筛选   总被引:4,自引:0,他引:4  
采用正交设计及方差分析法,筛选到Ⅰ号、Ⅱ号、Ⅲ号高浓度培养基配方。通过以85-10-6(s)为供试菌株、Ⅰ号配方在7吨发酵罐进行发酵试验,证实生产性能良好,发酵液平均含菌量71亿/ml,检查菌形、同步率、产晶率均属正常。  相似文献   

3.
目的:应用PCR-DGGE法和DNA测序分析云南籍G6PD缺乏症患者基因突变类型和特点、方法应用硝基四氮唑蓝(NBT)纸片法进行G6PD缺乏症定性筛查,G6PD/6PGD比值法验证,应用PCR—DGGE法和DNA测序分析46例云南籍G6PD缺乏症患者基因突变类型和特点。结果:46例云南籍G6PD缺乏症样本中有30例经PCR—DGGE法分析G6PDexon12发现有异常电泳条带,DNA测序证实26例(56、52%)为nt-1388G→A,4例(8.7%)nt-1376G→T.而PCR—DGGE法分析G6PDexon2未发现有异常电泳条带的样本出现。结论:(1)nt-1388G→A(56.52%)、nt-1376G→T(8.7%)是云南省主要的基因突变型也是中国人中最常见的两种突变型,揭示中华民族有着共同的起源;(2)所检样本中未发现nt95A→G。(3)应用PCR—DGGE法结合DNA测序检测G6PD缺乏症患者的基因型,阳性检出率高,方法简便、快捷、灵敏、结果准确可靠。  相似文献   

4.
利用大肠杆菌表达系统进行葡萄糖-6-磷酸脱氢酶(G-6-PD)的生化鉴定卢义钦(湖南医科大学生化教研室,长沙410078)关键词葡萄糖-6-磷酸脱氢酶(G-6-PD),大肠杆菌,表达葡萄糖-6-磷酸脱氢酶(G6PD)缺乏症在各民族人群中均有发现,据估...  相似文献   

5.
聚3-羟基丁酸酯(PHB)生物降解过程的研究   总被引:8,自引:0,他引:8  
利用DS9701菌株对聚3-羟基丁酸酯(PHB)膜进行降解,对降解到不同程度的PHB膜采用扫描电子显微镜观察其表面形态结构的变化,并对其降解产物进行分析测定.结果表明,PHB的生物降解首先发生在PHB表面的非晶部分,随后结晶部分开始降解,并且降解首先发生在球晶的中心部分.DS9701菌株所产生的PHB解聚酶主要降解PHB的第二个酯键,降解产物为二聚体.  相似文献   

6.
从麦田和蔬菜地土样中筛选到2株具有较高抗菌活性的生防菌株YD4-6和NV11-4,测定了其抑菌活性和诱导水稻防御性相关酶活性的变化。抑菌活性测定结果表明YD4-6和NV11-4对水稻纹枯病菌、水稻稻瘟病菌、油菜菌核病菌和白菜黑斑病菌均具有较强的抑菌活性。两菌株均不产生几丁质酶活性,但NV11-4能产生纤维素酶活性。针对其对水稻病原菌的抑菌活性和纤维素酶活性的差异及其特性,研究了2个菌株诱导水稻防御性酶活性的变化。结果表明,YD4-6和NV11-4菌株均可有效诱导水稻PPO、POD、PAL、SOD活性增强,MDA含量升高。接种水稻纹枯病菌和使用YD4-6和NV11-4菌株,在使用48 h后,水稻防御酶的活性增加并达到最高,其中NV11-4菌株诱导活性比较持久;YD4-6使用后,诱导水稻的MDA含量增幅较大。结果显示,2个菌株均可有效的诱导水稻防御性酶活性增强和MDA含量增加。经16S rRNA鉴定后,菌株Y4-6确定为蜡质芽孢杆菌,NV11-4确定为枯草芽孢杆菌。  相似文献   

7.
利用E.coli BL21/pCDFDuet-gdh—cr-X共表达全细胞催化6-氰基-(5R)-羟基-3-羰基己酸叔丁酯不对称还原合成6-氰基-(3R,5R)-二羟基已酸叔丁酯。结果表明:在菌体用量4.85g/L、葡萄糖与底物质量浓度比为1:1、温度28℃、pH7.0条件下,80.0g/L6-氰基-(5R)-羟基-3-羰基己酸叔丁酯生物还原2h后,底物转化率可达99.0%,产物d.e.值大于99.5%。在考察范围内,NADP^+用量对催化效率无显著作用。  相似文献   

8.
本文报道了用Fmoc固相法合成3种胰岛素A链小环(A8-10)被不同碱性氨基酸取代的A链类似物,并分别与天然胰岛素B链重组成相应胰岛素类似物;经受体结合,整体活性及抗体结合实验,均表现出相应的活性。从中可以推测出:A链小环区域不是胰岛素表现生物活性的重要部位,而是胰岛素与其抗体结合较重要的区域。  相似文献   

9.
邻苯二甲酸二(2-乙基己基)酯(DEHP)是目前使用最广泛的增塑剂之一,DEHP具有毒性,长期暴露会对机体的多个系统产生损害,特别是对雄性生殖系统的毒性作用更为明显。DEHP通过诱导氧化应激、调控细胞自噬,促进生精细胞和睾丸间质细胞凋亡、抑制睾酮合成、破坏血-睾屏障、诱导睾丸支持细胞铁死亡以及影响子代雄性的表观遗传等,造成生殖器官的病理损伤。本文就DEHP对睾丸的毒性作用及机制进行综述,拟为男性生殖障碍的防治研究提供新思路。  相似文献   

10.
选择R-羰基还原酶和葡萄糖脱氢酶双酶,协同催化(R)-6-氰基5-羟基-3-羰基己酸叔丁酯不对称还原制备阿托伐他汀关键手性合成子6-氰基-(3R,5R)-二羟基已酸叔丁酯。转化条件优化结果显示:在不添加外源性辅酶NADP(H)、菌体用量15.0g/L、147.0g/L(R)-6-氰基-5-羟基-3-羰基己酸叔丁酯、128.2g/L葡萄糖,30℃、pH6.5条件下反应6h后,底物转化率达到100%,产物d.e.值大于99.5%。  相似文献   

11.
A new uridine derivative, 2"-O-(2,3-dihydroxypropyl)uridine, and its 3"-phosphoramidite were obtained for direct introduction into oligonucleotides during automated chemical synthesis. Oligonucleotides 10 to 15 nt long harboring 2"-O-(2,3-dihydroxypropyl)uridine residues were synthesized; periodate oxidation of these oligomers gave oligonucleotides containing 2"-O-(2-oxoethyl)uridine residues. The presence of a reactive aldehyde group in 2" position of the carbohydrate moiety was confirmed by the interaction withp-nitrophenylhydrazine and methionine methyl ester. The thermostability of DNA duplexes containing modified units does not practically differ from that of the natural analogues.  相似文献   

12.

Aims

The (2′S,7′S)-O-(2-methylbutanoyl)-columbianetin (OMC) is a novel secondary metabolite extracted from Corydalis heterocarpa, which has long been used as a folk medicine for various inflammatory diseases in Korea. We examined the effect of OMC on allergic rhinitis (AR).

Main methods

We assessed the therapeutic effects and regulatory mechanisms of OMC on the phorbol 12-myristate 13-acetate plus A23187-stimulated mast cell line, HMC-1 cells and ovalbumin (OVA)-induced AR models.

Key findings

OMC significantly decreased the releases of histamine and tryptase from stimulated HMC-1 cells. The degranulation process, characterized by morphological extension of the filopodia on the surface and membrane ruffling, was strongly induced in the stimulated-HMC-1 cell, however OMC suppressed the morphological changes in stimulated-HMC-1 cells. OMC reduced the production and mRNA expression of inflammatory cytokines. These inhibitory actions by OMC were dependent on the regulation of mitogen-activated protein kinases, nuclear factor-κB, and caspapase-1 signaling pathways. In the AR animal model, the increased rub scores and AR biomarkers (histamine and IgE) in ovalbumin (OVA)-sensitized mice were significantly reduced by the administration of OMC. Furthermore, eosinophils and mast cell infiltrations in nasal mucosa tissue were also blocked through the regulation of macrophage-inflammatory protein and intercellular adhesion molecule-1 levels.

Significance

OMC showed the possibility to regulate AR in activated mast cells and OVA-induced AR models. Hence, we suggest that OMC is a powerful and feasible new agent to suppress AR.  相似文献   

13.
In order to elucidate the relation between the difference in cellulase activity among various strains of P. oryzae and the optimum pH at alkaline side, and also to know the relation between the intra- and extra-cellulases, the elution patterns of the enzymes from the Sephadex G–100 column were compared and the occurrence of the enzyme fractions showing the optimum pH at alkaline side was investigated.

The elution patterns of the intracellular cellulases were shown to be relatively constant, but those of the extracellular enzymes did not. The peak e appeared comparatively constant, but the peak c was considered to undergo some change during the excretion into the medium.

The optimum pH at alkaline side was shown to occur in the peak e among five peaks on Sephadex G–100 of the partially purified intra- and extra-cellular cellulases. The peak seems to be significant for P. oryzae.  相似文献   

14.
A novel potato micro-tuber-inducing compound was isolated from the culture broth of Lasiodiplodia theobromae Shimokita 2. The structure of the isolated compound was determined as (3R,6S)-6-hydroxylasiodiplodin by means of spectroscopic analyses, the modified Mosher method, and chemical conversion. The compound showed potato micro-tuber-inducing activity at a concentration of 10?4 M, using the culture of single-node segments of potato stems in vitro.  相似文献   

15.
16.
A new series of six chromone-derived compounds and their Cu(II) complexes have been synthesized and characterized by their physical, spectral and analytical data. The ligands and their Cu(II) complexes were screened for their in vitro antibacterial activity against four Gram-negative (Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, Shigella flexneri) and two Gram-positive (Bacillus subtilis, Staphylococcus aureus) bacterial strains by agar-well diffusion method. The ligands were found to exhibit either no or low-to-moderate activities against one or more bacterial species whereas, the Cu(II) complexes exhibited moderate-to-high activity. The ligands which were inactive before complexation became active upon complexation with the Cu(II) metal ion and less active became more active.  相似文献   

17.
目的:探讨不同类型冠心病患者血清白介素-37(IL-37)的水平及其与血清白介素-6(IL-6)、白介素-10(IL-10)、C反应蛋白(CRP)水平的关系。方法:选取急性心肌梗死患者20例(AMI组)、不稳定性心绞痛患者26例(UAP组)、稳定性心绞痛患者20例(SAP组)及冠脉造影正常者26例(CON组)为研究对象,采用酶联免疫吸附法(ELISA)测定其血清IL-37、IL-6、IL-10和CRP的水平并分析其相关性。结果:1UAP组、AMI组血清IL-37水平均较对照组(CON组)显著增高(p0.05),而SAP组与CON组比较无明显差异(P0.05)。2冠心病患者的血清IL-37水平与其血清CRP(r=0.3,P0.05)、IL-6(r=0.4,P0.05)水平均存在显著正相关性,与IL-10水平无明显相关(P=0.16)。当排除SAP组患者后,冠心病患者的血清IL-37水平与CRP(r=0.3,P0.05)、IL-6(r=0.5,P0.05)、IL-10(r=0.2,P0.05)水平均显著相关。结论:急性冠脉综合症(ACS)患者的血清IL-37水平显著升高,并与IL-6、IL-10、CRP水平相关,可能参与了ACS发病过程中的炎症反应。  相似文献   

18.
本文研究鹊肾树Streblus asper心材的乙酸乙酯部分化学成分及体外抗菌活性.运用正相硅胶柱色谱层析,反相C-18柱色谱层析和Sephadex LH-20分高、纯化,最终得到8个化合物,经波谱解析并结合理化鉴定确定化合物结构为:银杏双黄酮(1)、异黄酮-4′-甲氧基-7-α-L-鼠李糖-(1→6)-β-D-葡萄糖(2)、鼠李柠檬素-3-O-β-D-半乳糖苷(3)、β-香树脂酮(4)、β-谷甾醇(5)、香革酸(6)、山俞酸(7)、二十六烷酸(8).除化合物5外,均为首次从该植物中提取到.此外研究了化合物1-4的抗菌活性,实验表明化合物2具有一定的抑菌活性.  相似文献   

19.
Antibacterial activities of as-synthesized nanoparticles have gained attention in past few years due to rapid phylogenesis of pathogens developing multi-drug resistance (MDR). Antibacterial activity of copper nanoparticles (CuNPs) on surrogate pathogenic Gram-negative bacteria Escherichia coli (MTCC no. 739) and Proteus vulgaris (MTCC no. 426) was evaluated under culture conditions. Three sets of colloidal CuNPs were synthesized by chemical reduction method with per batch yield of 0·2, 0·3 and 0·4 g. As-synthesized CuNPs possess identical plasmonic properties and have similar hydrodynamic particle sizes (11–14 nm). Antibacterial activities of CuNPs were evaluated by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) tests, cytoplasmic leakage and reactive oxygen species (ROS) assays. MIC and MBC tests revealed dose dependence bactericidal action. Growth curves of E. coli show faster growth inhibition along with higher cytoplasmic leakage than that of P. vulgaris. This might be because of increased membrane permeability of E. coli. CuNP–microorganism interaction induces oxidative stress generated by ROS. Leakage of cytoplasmic components, loss of membrane permeability and ROS generation are the primary causes of CuNP-induced bacterial cell death. As-synthesized CuNPs exhibiting promising antibacterial activities and could be a promising candidate for novel antibacterial agents.  相似文献   

20.
通过控制单核能大小 ,将 1 2 C离子注入小麦种子胚乳 ,结果引起 M1 代植株的较大变化。这些变化包括 :生物学性状的变异 ;根尖细胞染色体畸变率和微核率的显著提高 ;POD酶活性显著提高和 CAT酶活性、MDA含量和蛋白质含量的较大程度的下降等。本文也讨论了诱变胚乳对胚作用的可能机理  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号