共查询到20条相似文献,搜索用时 131 毫秒
1.
水杨酸对黄瓜叶片抗氧化剂酶系的调节作用 总被引:27,自引:0,他引:27
分析了水杨酸(SA)对黄瓜(CucumissativusL.)叶片抗氧化剂酶系活性及活性氧水平的调节作用。不同浓度的SA(0.5mmol/L、1mmol/L、2.5mmol/L、5mmol/L)均能显著地提高被处理叶片超氧化物歧化酶(SOD)和过氧化物酶(POD)活性,而且还能诱导同株的非处理叶片中SOD和POD活性增加。用1mmol/LSA处理第一片真叶,在处理后6~72h,POD活性增加了22%~67%,同株非处理的第二片真叶POD活性增加了14%~86%,但是,在SA处理后3h之前以及处理96h之后,POD活性没有变化。SA能够显著降低超氧物阴离子含量和提高过氧化氢水平,但它对过氧化氢酶(CAT)活性的抑制作用很弱,表明SA提高体内过氧化氢含量的原因主要是通过提高SOD活性而不是抑制CAT活性。同工酶分析表明,SA不能诱导新的SOD同工酶,但可以诱导新的POD同工酶。 相似文献
2.
3.
鲜盾叶薯蓣中原始皂甙的分离与鉴定 总被引:4,自引:0,他引:4
从盾叶薯蓣(Dioscorea zingiberensis Wright)新鲜根茎的甲醇提取物分离到薯蓣皂甙元棕榈酸酯(diosgenin palmitate)、β-谷甾醇(β-sitosterol)、纤细皂甙(gracillin)、原纤细皂甙(protogracillin)和原盾叶皂甙(protozingiberemissaponin),后者为一新甾体皂甙,结构推定为3-O-{α-L-鼠李吡喃糖(1→3)-[β-D-葡萄吡喃糖(1→2)]-β-D-葡萄吡喃糖}-26-O-{β-D-葡萄吡喃糖}-薯蓣皂甙元(3-O-{α-L-rhamnopyran0syl(1→3)-[β-D-glucopyranosyl(1→2)]-β-D-glucopyranosyl}-26-O-{β-D-glucopyranosyl}-diosgenin)。 相似文献
4.
为研究新工艺提取盾叶薯蓣薯蓣中薯蓣皂甙元的最佳实验指标,以薯蓣皂甙元得率为评价参数,采用6因素5水平的正交实验,用分光光度法对25种提取方法所得到的薯蓣皂甙元进行比较分析。结果表明,硫酸浓度对薯蓣皂甙元提取的影响最大,在实验室条件下,可采用20g样品加甲醇回流提取4h,回流速度为10min/次,用2.5mol/L的硫酸水解6h,120号溶剂汽油回流提取2h,回流速度为15min/次,能清洁快速提取盾叶薯蓣中的薯蓣皂甙元。 相似文献
5.
胡杨离体器官发生及试管无性系的建立 总被引:21,自引:0,他引:21
研究了离体条件下胡杨(Populus euphratica Oliver)茎段、叶片及愈伤组织的器官发生和植株再生技术。离体培养以MS为基本培养基并附加40mg/L腺嘌呤和500mg/L水解乳蛋白。离体叶片和茎段在BA为0.5mg/L和NAA为0.5mg/L的培养基上诱导产生愈伤组织,并在含0.25mg/LBA和0.5mg/LNAA的培养基上继代增殖。BA为0.5mg/L和NAA为0.1mg/L可诱导叶片和愈伤组织发生不定芽,诱导频率分别为100%和82.9%,对于茎段,BA和NAA分别为0.1mg/L和0.01mg/L时诱导不定芽频率可达83%。试管苗在大量元素减半并附加0.015mg/LNAA的MS培养基上诱导生根,生根率达86.2%。 相似文献
6.
盾叶薯蓣地上部分的三个新甾体皂甙 总被引:11,自引:0,他引:11
从盾叶薯蓣Dioscorea zingiberensis Wright地上部分分离鉴定了四个甾体皂甙,经鉴定甙A为约莫皂甙元-3-O-[α-L-鼠李吡喃糖基(1→2)]-β-D-葡萄吡喃糖甙;甙B为24α-羟基约莫皂甙元-3-O-[α-L-鼠李吡喃糖基(1→2)]β-D-葡萄吡喃糖甙;甙C为约莫皂甙元-3-O-[α-L-鼠李吡喃糖基(1→2)][β-D-葡萄吡喃糖基(1→4)]-β-D-葡萄吡喃糖基;甙D为约莫皂甙元-3-O-[α-L-鼠李吡喃糖基(1→2)][β-D-葡萄吡喃糖基(1→3)]-β-D-葡萄吡喃糖甙。前三者为新化合物,分别命名为盾叶皂甙A_1、A_2、A_3(zingiberoside A_1、A_2、A_3),其中盾叶皂甙A_2的甙元为一新甾体皂甙元,命名为盾叶皂甙元(zingiberogenin)。 相似文献
7.
藏红花愈伤组织诱导及其细胞培养的研究 总被引:4,自引:0,他引:4
藏红花幼叶愈伤组织的诱导频率在MS,B5和White三种培养基上均高达98%;幼叶和芽的诱导率差异不大,高达99%;不同时期的叶片差异较大,以幼叶诱导为佳;球茎诱导率为近80%;激素配比以2.4-D2.0mg/L,BAP0.1~0.5ml/L为宜。在继代培养阶段,MS比B5和White更适合细胞的快速生长繁殖;并且以叶片的愈伤组织生长较快,芽次之,球茎最慢,适合于细胞生长的激素配比为NAA2.0~3.0mg/L,BAP0.5~1.0mg/L为宜。 相似文献
8.
荷兰鸢尾(Iris xiphium L. var. hybridum)的组织培养 总被引:1,自引:0,他引:1
取荷兰鸢尾(IrisxiphiumL.var.hybridum)鳞茎片不同部位外植体块,接种于附加不同激素配比的基本培养基上,其中取自鳞茎片基部外植体块2mm×2mm×2mm,培养基为MS+BA1.0mg/L+NAA0.2mg/L的不定芽诱导率为最高(70%);最理想的增殖培养基为MS+BA2.0mg/L+NAA0.2mg/L。不定芽直径4~5mm,培养基为MS+BA0.2mg/L+NAA0.5mg/L有利于不定根的发生,诱导生根率达833%。试管苗不经练苗可直接出瓶,移栽于泥炭∶田土∶河沙=1∶1∶1(V/V)的基质中。 相似文献
9.
哑特猕猴桃微繁工艺流程的研究 总被引:5,自引:0,他引:5
选用哑特猕猴桃腋芽为外植体。在不同发育阶段适宜培养基组成:芽增殖生长培养基为MS+6-BA0.5mg/L+IAA0.1mg/L(或者IBA0.1mg/L;NAA0.1mg/L),其在苗基部呈辐射状萌发多个嫩枝与主茎伸长生长同步进行的繁殖特点,有利提高繁殖率。40d繁殖系数为5-7。诱导生根培养基为MS+IBA0.5mg/L+IAA0.2mg/L,生根率达97.1%,培养30d,平均苗高3.5cm, 相似文献
10.
李耿光 《植物生理与分子生物学学报》1996,(3)
向日葵籽苗下胚轴原生质体,培养在含有BA0.5mg/L,2,4-D0.5mg/L,NAA0.1mg/L和葡萄糖0.55mg/L的改良Kao培养基中,24~28h后,原生质体开始分裂。包埋在琼脂糖0.6%中的原生质体,培养5d后,分裂频率达95%以上。生长旺盛的小愈伤组织转移到含有2ip0.1mg/L,IAA0.01mg/L,腺嘌呤40mg/L和GA30.01mg/L的Thompson液体培养基上13d后,原生质体诱导的少数愈伤组织发生根分化。 相似文献
11.
Kyaw W. Naing Muhammad Anees Xuan H. Nguyen Yong S. Lee Seung W. Jeon Sang J. Kim Myung H. Kim Kil Y. Kim 《Journal of Phytopathology》2014,162(6):367-376
For field application of a bacterial strain used to control Phythophthora capsici, we will need a biologically and economically efficient carrier medium. The known antagonist Paenibacillus ehimensisKWN38 was grown in a grass medium where it showed high antifungal and lytic enzyme activities. To demonstrate the potential of P. ehimensisKWN38 for biocontrol of late blight disease in pepper, pot trials were conducted by treating the 1‐month‐old plants with water (W), a selected grass medium (G3), G plus P. ehimensisKWN38 inoculation (G3P) or synthetic fungicide (F). The shoot dry weight in G3P was higher than that in W and F treatments at 15 days after zoospore infection (DZI). The root dry weight in G3P was also higher than that in W. The root mortality of G3 and W increased over 58 and 80% at 15 DZI, and some plants in those treatments wilted due to the failure of root physiology. The plants in G3P and F survived well because of their better root health conditions. Soil cellulase activity of G3P was consistently higher than that of W and F at earlier observation times (0, 2 and 6 DZI). The root β‐1,3‐glucanase activity of G3P promptly increased to maximum shortly after zoospore infection and reached the maximum value of 51.12 unit g?1 of fresh weight at 2 DZI. All these results indicate that inoculation of P. ehimensisKWN38 to the root zone of potted pepper plants increases plant growth, root and soil enzyme activities and alleviates the root death caused by infection with P. capsici zoospores. 相似文献
12.
James A Mbah Moses N Ngemenya Ashime Louis Abawah Smith B Babiaka Lina N Nubed Kennedy D Nyongbela Njimoh Dieudonne Lemuh Simon MN Efange 《Annals of clinical microbiology and antimicrobials》2012,11(1):1-10
Background
The global burden of bacterial infections is high and has been further aggravated by increasing resistance to antibiotics. In the search for novel antibacterials, three medicinal plants: Peperomia vulcanica, Peperomia fernandopoioana (Piperaceae) and Scleria striatinux (Cyperaceae), were investigated for antibacterial activity and toxicity.Methods
Crude extracts of these plants were tested by the disc diffusion method against six bacterial test organisms followed by bio-assay guided fractionation, isolation and testing of pure compounds. The minimum inhibitory (MIC) and minimum bactericidal (MBC) concentrations were measured by the microdilution method. The acute toxicity of the active extracts and cytotoxicity of the active compound were performed in mice and mammalian cells, respectively.Results
The diameter of the zones of inhibition (DZI) of the extracts ranged from 7?C13?mm on Escherichia coli and Staphylococcus aureus of which the methylene chloride:methanol [1:1] extract of Scleria striatinux recorded the highest activity (DZI?=?13?mm). Twenty-nine pure compounds were screened and one, Okundoperoxide, isolated from S. striatinux, recorded a DZI ranging from 10?C19?mm on S. aureus. The MICs and MBCs indicated that the Peperomias had broad-spectrum bacteriostatic activity. Toxicity tests showed that Okundoperoxide may have a low risk of toxicity with an LC50 of 46.88???g/mL.Conclusions
The antibacterial activity of these plants supports their use in traditional medicine. The pure compound, Okundoperoxide, may yield new antibacterial lead compounds following medicinal chemistry exploration. 相似文献13.
A series of 10 3-(hetarylaminomethylene)quinolinediones, 12 3-(substituted aminopropenoyl)-4-hydroxyquinolinones, and 10 3-(substituted aminomethylene-5-oxo-pyrazolinyl)-4-hydroxyquinolinones were synthesized as novel enaminones derived from 3-(un)substituted 4-hydroxyquinolin-2(1H)-ones in 72-94% yields and assayed for their molluscicidal activities against Biomphalaria alexandrina and Lymnaea natalensis snails. Some of the tested enaminones presented high molluscicidal activities (LC(50)20ppm). The new compounds showed more potency against hatchability of B. alexandrina egg masses, the infection rate and prepatent period of the snails. In addition, these derivatives revealed potential larvicidal effects (100% mortality) on both miracidia and cercariae of Schistosoma mansoni at reduced exposure time. The selected active derivatives were examined against Daphnia magna and their nontoxic effect at all sublethal, lethal, and higher concentrations suggests that these compounds can play an important role as molluscicides and larvicides with environmental safe properties. 相似文献
14.
结核分枝杆菌ICL mRNA特异性10-23脱氧核酶切割 活性的鉴定及其切割特点 总被引:3,自引:0,他引:3
为鉴定结核分枝杆菌异柠檬酸裂合梅(ICL)特异性的10-23DRz在无细胞体系切割ICL mRNA的活性,并探讨其在不同条件下以及联合应用时对靶mRNA的切割特点,采用计算机软件模拟ICL mRNA的二级结构,据此选择适合的待切割靶点并设计针对相应靶点的特异性10-23DRz(DZ1~DZ5).PCR法扩增获得icl基因并克隆入质粒pET32a+.采用T7 RNA聚合酶体外转录法获取ICL全长mRNA后分别用DZ1~DZ5在无细胞体系中对ICL mRNA进行切割,切割产物经变性聚丙烯酰胺凝胺电泳后用银染法鉴定各DRzs的活性.选择切割活性最强的DZ4考察不同10-23DRz剂量、不同反应时间、不同镁离子浓度条件下及不同错配或突变10-23DRz的切割特点.联合应用DZ1、DZ4及DZ5在无细胞体系中对ICL mRNA进行切割,检测10-23DRz联合应用对切割效率的影响.结果表明,DZ1、DZ3、DZ4及DZ5可在无细胞体系中有效地切割ICL mRNA,其切割效率在30.8%~64.5%之间.对DZ4切割活性的检测发现,其对靶mRNA的切割具有剂量和时间的依赖性;在2~20 μmol/L范围内,DZ4的切割活性与Mg2+浓度呈正相关;DZ4单侧底物结合臂上含一个不与靶mRNA配对的碱基时其切割效率大大降低,两侧底物结合臂上各含一个不配对的碱基或活性中心域第6位出现碱基突变(G→C)时,DZ4完全丧失切割活性.联合应用2种或2种以上10-23DRz可显著增强对底物RNA的切割效率.10-23 DRz特异、有效地切割结核分枝杆菌ICL全长mRNA并显示一定的叠加效应,有望用于抗结核分枝杆菌潜伏感染的基因治疗. 相似文献
15.
B. SPEISER 《The Annals of applied biology》1999,135(1):449-455
Slug problems in arable crops and vegetables have increased drastically during the past few decades. Observations on slug damage to oilseed rape suggested that fresh, anaerobically digested organic material from a biogas production plant is molluscicidal. To find out whether digested matter can be used for the control of agricultural pest slugs, a series of exeriments were carried out. The laboratory experiments demonstrated strong mollusc repellent and molluscicidal effects of digested organic matter against the three most important pest slugs of Switzerland, Arion lusitanicus, A. distinctus and Deroceras reticulatum. The effects were restricted to fresh digested matter and were rapidly lost when the material was stored, and also after application in the field. In the field experiment, fresh digested matter greatly reduced slug damage to lettuce in comparison with the untreated plots. At present, the chemical nature of the molluscicidal compound(s) in digested matter is unknown, but environmental pollutants such as heavy metals can be ruled out. Current research aims at a new formulation which is easier to apply and has a longer-lasting molluscicidal or slug-repellent effect, and at optimising the dosage and number of applications. 相似文献
16.
The effects of seven potential phagostimulants and of four molluscicidal compounds on feeding were examined by confining slugs with agar gels containing the chemicals in varying concentrations. Sugars generally increased the amount of gel ingested; sucrose more than glucose, lactose and fructose. Feeding increased with increasing sucrose concentration to a maximum and then fell progressively: the optimum concentration lay between 2.5% and 5%. The sweeteners saccharin and aspartame at concentrations up to 2.5% did not increase feeding. Addition of the molluscicides metaldehyde, methiocarb and ferric acetylacetonate to gels containing 2.5% sucrose progressively reduced feeding at concentrations of 0.001% and above. Metaldehyde reduced ingestion more than methiocarb and ferric acetylacetonate was intermediate. The molluscicidal herbicide Ioxynil deterred feeding completely at concentrations of 0.001%. The implications for slug bait development are discussed. 相似文献
17.
二氮嗪预处理上调Bcl-2/Bax蛋白比值减少缺氧复氧所致体外培养的海马神经元凋亡 总被引:15,自引:1,他引:14
线粒体内膜ATP敏感钾通道(mitochondrial ATP-sensitive potassium channel,mitoKATP通道)的激活在药物预处理增强神经元对各种损伤的耐受力过程中发挥着重要作用。神经元内含有丰富的mito KATP,通道,二氮嗪(diazoxide,DZ)为选择性的mitoKATP通道开放剂,本实验探讨了DZ预处理能否减少缺氧复氧所致的海马神经元凋亡,以及DZ如何调控Bcl-2蛋白和Bax蛋白的表达。原代培养9~10d的Sprague-Dawley大鼠海马神经元随机分为5组:对照组、DZ0μmol/L、DZ30μmol/L、DZ100μmol/L和DZ100μmol/L+5-羟癸酸(5-hydroxydecanoate,5-HD)100μmol/L。除对照组外,其他四组神经元白缺氧前3d开始,每天DZ预处理1h,连续3d。体外缺氧4h,于复氧后24h,四唑蓝比色法测定海马神经元存活率,annexin V-FITC流式细胞术测定凋亡率,Western blot法检测Bcl-2和Bax蛋白的表达量。结果显示:与对照组比较,缺氧复氧损伤显著降低海码神经元的存活率,升高凋亡率。与其他浓度比较,100μmol/LDZ预处理使神经元存活率升高约15%,而凋亡率降低约12%:Bcl-2蛋白表达增强约60%,Bax蛋白表达下降近30%。5-HD消除DZ对神经元的保护作用。因此,100μmol/LDZ可通过上调Bcl-2蛋白表达,降低Bax蛋白表达,减少缺氧复氧后海马神经元的凋亡。 相似文献
18.
Morphological and Neurochemical Effects of Diazepam and Phenobarbital on Selective Culture of Neurons from Fetal Rat Brain 总被引:1,自引:0,他引:1
Jean-Luc Daval Anne Pereira De Vasconcelos Isabelle Lartaud 《Journal of neurochemistry》1988,50(3):665-672
The responses to diazepam (DZ) and phenobarbital (PhB) were studied in enriched neuronal primary cultures from rat embryo hemispheres. Cells were grown in chemically defined medium and the drugs were added for 3 days to cultures, at pharmacologically active concentrations. Following exposure to DZ or to PhB, morphological changes, such as less prominent neuronal processes, were observed in neurons. It was also shown that each drug reduced the specific uptake of 2-deoxy-D-glucose by the cells and interfered with protein and RNA metabolism. It was concluded that both DZ and PhB might affect, at least transiently, the normal growth of neurons in culture. 相似文献
19.
Dr. Samuel Singer Thomas B. Bair Terry B. Hammill Aminata Maman Berte Margarita M. Correa-Ochoa Angela D. Stambaugh 《Journal of industrial microbiology & biotechnology》1994,13(2):112-119
Summary Strain SS86-4 was one of 40Bacillus brevis strains shown to be molluscicidal to the schistosomiasis snail vectorBiomphalaria glabrata. When grown in mB4 medium in 2-L fermentors, SS86-4 was molluscicidal only if fructose or phenylalanine was present in the medium. This is reminiscent of secondary fermentation factor effects, in this case an antioxidant effect. In vivo proteases also were capable of reducing molluscicidal activity. The molluscicidal toxin has an LC50 of 1 g toxin protein ml–1 (approx. 1 p.p.m.) and may be described as a small proteinaceous, heat-stable, oxygen-sensitive entity associated with the particulate portion of the cell wall fraction ofB. brevis that is formed prior to sporulation. Initial information indicates that its HPLC signature shows major peaks at 148.37 and 163.96 s and consists of two bands of approximately 5.3 kDa and 8.7 kDa on PAGE gel. 相似文献
20.
Parihar VK Dhawan J Kumar S Manjula SN Subramanian G Unnikrishnan MK Rao CM 《Chemico-biological interactions》2007,170(1):49-58
Dehydrozingerone (DZ) was explored for in vitro-in vivo antioxidant potential and in vivo radioprotective activity against whole body gamma irradiation in Swiss albino mice. DZ scavenged the ABTS (2, 2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) and DPPH (1, 1-dipehnyl-2-picrylhydrazyl) free radicals at room temp. DZ reduced Fe (III) to Fe (II) at pH 7.4 and scavenged the NADH/phenazine methosulfate generated superoxide radical in cell free system. DZ also scavenged the nitric oxide radical generated by sodium nitroprusside. To evaluate the radioprotective activity, mice were exposed to whole body gamma irradiation 30 min after the drug treatment at a dose rate of 1.66 Gy/min. Pretreatment with DZ 75, 100 and 125 mg/kg, i.p. reduced the radiation induced mortality and increased the mean survival times (MSTs). An i.p. dose of DZ 100 mg/kg was found the most effective dose in preventing radiation sickness and increasing the MST. Pretreatment DZ100 mg/kg maintained the spleen index (spleen weight/body weight x 100) and stimulates the endogenous spleen colony forming units (CFU). Pretreatment with DZ100 mg/kg maintained the villus height close to normal, prevents mucosal erosion and basement membrane damage in irradiated mice jejunum. However, no significant reductions in dead, inflammatory and mitotic cells were observed in DZ pretreated mice, but there was an increased in crypt cells proliferation and regeneration. Pretreatment with DZ100 mg/kg significantly elevated the endogenous antioxidant enzymes (GSH, GST and SOD) in mice at 2, 4 and 8 h post sham irradiation. Radiation induced fall in endogenous antioxidant enzymes was significantly prevented by DZ pretreatment. Pretreatment with DZ 75 and 100 mg/kg reduced the radiation induced micronucleated polychromatic erythrocytes (MPCE) and normochromatic erythrocytes (MNCE) in mice bone marrow. DZ also maintained the polychromatic erythrocytes (PCE) and normochromatic erythrocytes (NCE) ratio (P/N ratio) in irradiated mice. Dose modifying factor (DMF) was calculated by using the graded radiation dose (8.0, 9.0, 9.5 and 10 Gy). DZ 100 mg/kg elevated radiation LD(50) from 9.1 to 10.0 Gy, indicating the DMF of 1.09. 相似文献