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1.
利用正交实验设计,对芒果SRAP-PCR反应的5因素(Mg2+、dNTPs、模板DNA、引物和Taq DNA聚合酶)4水平的扩增效果进行研究,确立适合芒果SRAP-PCR反应的最佳体系。总体积25μL的SRAP-PCR优化的最佳反应体系中含有:2.5μL 10×buffer、20 ng模板DNA、2.5 mmol/L Mg2+、0.2 mmol/L dNTPs、0.4μmo1/L Primer、Taq DNA聚合酶1.5 U。并运用该体系从153对引物组合中初步筛选出50对SRAP引物组合。建立的SRAP标记可为芒果遗传多样性、分子标记及辅助育种等提供研究基础。  相似文献   

2.
利用正交设计优化甘蔗SRAP-PCR反应体系   总被引:2,自引:0,他引:2  
利用正交设计L16(45)对甘蔗SRAP-PCR反应体系的五大因素(Mg2+、dNTPs、引物、模板DNA、Taq酶)在4个水平上进行优化,得到如下结论:各因素水平变化对PCR反应的影响从大到小依次是:Mg2+、dNTPs、引物、Taq酶和模板DNA;通过对各因素进行筛选,建立甘蔗SRAP-PCR反应的最佳体系(20μL)为:dNTPs 0.25 mmol/L、引物0.1μmol/L、Mg2+2.5 mmol/L、Taq酶0.25U和模板DNA 60 ng。  相似文献   

3.
芒果ISSR反应体系的建立与优化   总被引:2,自引:0,他引:2  
运用L16(45)正交设计对芒果ISSR反应的5个因素,即DNA模板浓度、Mg2+浓度、dNTPs浓度、引物浓度、Taq DNA聚合酶浓度在4个水平上进行优化试验,通过不同反应体系扩增效果比较,建立优化的芒果ISSR反应体系,即25μL的PCR体系中含有DNA模板25 ng、Mg2+浓度为1.5 mmol/L、dNTPs 0.3 mmol/L、引物0.32μmol/L、Taq DNA聚合酶1.25 U。这为进一步运用ISSR标记在DNA分子水平上对芒果种质资源进行分析奠定基础。  相似文献   

4.
以国兰杂交品种(系)为材料,采用L16(45)正交试验设计对Taq DNA聚合酶、Mg2+、dNTPs、模板及引物等5个重要影响因素进行优化,确定国兰杂交品种(系)SRAP-PCR反应的最优反应体系为(25μL体系):Taq DNA聚合酶,1 U;Mg2+,1.8 mmol/L;dNTPs,0.08 mmol/L;模板DNA,100 ng;引物,上下游各0.3 mmol/L;10×PCR Buffer,2.5μL。此外,本试验采用DNA混合池技术(DNA pooling)快速筛选SRAP引物,从180对SRAP引物组合中筛选出39对扩增产物丰富、多态性高的引物组合。与常规方法相比,该技术明显缩短试验周期、节约了模板用量,为快速高效筛选SRAP引物提供了新思路。  相似文献   

5.
黄春琼  刘国道 《热带作物学报》2009,30(11):1584-1588
利用正交设计试验,对影响ISSR-PCR的Mg~(2+)、dNTPs、引物、Taq DNA聚合酶和模板DNA 5个因素进行优化试验.结果表明:25μL ISSR-PCR反应体系中各因素的最佳条件为Mg~(2+)2.5 mmol/L、dNTPs 0.25 mmol/L、引物0.2μmol/L、Taq DNA聚合酶1.0 U,模板DNA 40 ng.通过对狗牙根ISSR-PCR最佳反应体系进行梯度退火试验,得到引物UBC881的最佳退火温度为50.5℃.该体系在24个狗牙根种质中获得较好的扩增结果,该优化体系为今后利用ISSR技术进行狗牙根属种质资源的遗传多样性分析奠定了技术基础.  相似文献   

6.
甜菜ISSR-PCR反应体系的优化   总被引:3,自引:0,他引:3  
以甜菜基因组DNA为模板,研究了ISSR的主要影响因素,建立一套适宜于甜菜的ISSR优化反应体系及程序,并对该优化体系进行了验证.实验结果表明:①优化的ISSR扩增的反应体系为:20μL的反应体积中包括2.5mmol/L MgCl2,0.25mmol/L dNTPs,1.5U Taq DNA聚合酶,0.5μmol/L引物,10×PCR Buffer 2μL,100ng DNA模板.②优化的PCR扩增条件为:94℃预变性3min,然后94℃变性30s,45℃退火30s,72℃延伸1min,35个循环后,72℃延伸5min.③利用优化的反应体系仅用1条引物就能将10份甜菜材料区分开.  相似文献   

7.
芒果SSR-PCR反应体系的优化   总被引:1,自引:0,他引:1  
通过正交实验,以芒果品种金煌芒为材料,对影响芒果SSR-PCR反应体系中的Mg2+、dNTPs、Taq酶、模板DNA、引物这5个因素进行了优化。结果表明,各因素水平变化对PCR反应影响的显著性依次为:模板DNAdNTPs引物Mg2+Taq酶。最终确立SSR反应体系的最优条件为:20μL体系中,10×buffer2μL,模板DNA80ng,dNTPs0.4mmol/L,引物0.2μmol/L,Mg2+1.8mmol/L,Taq酶0.75U。  相似文献   

8.
以中粒种咖啡部分种质为试材,采用U25(55)均匀设计表,对影响ISSR和RAPD标记的模板DNA、Mg2+、dNTPs、TaqDNA聚合酶和引物浓度5个因素进行优化,分别建立适合于中粒种咖啡ISSR-PCR和RAPD-PCR标记的反应体系。结果表明:2种标记的反应体系相似,20 μL的反应体系中含DNA模板20 ng,Mg2+ 1.5 mmol/L,dNTPs 0.3 mmol/L,Taq酶1.25 U,引物0.6 μmol/L。利用所确立的体系对13份中粒种咖啡种质进行扩增,结果条带清晰明亮,多态性好  相似文献   

9.
以柱花草奥克雷品种为材料,采用改良的CTAB法提取基因组DNA,对影响AFLP反应体系的主要因素进行了优化,建立了柱花草的AFLP反应体系。结果表明:20 μL为最佳反应体系,酶切体系中DNA模板量为1 000 ng,用5 U EcoR I 37℃酶切2 h、5 U Mse I 65℃酶切2 h效果最佳;分别取5 μL酶切液、1 μL T4连接酶(5 μL/L)、1 μL EcoR I接头、1 μL Mse I接头、2 μL缓冲液(T4DNA酶自带),于22℃下连接10 min效果最佳;预扩增体系中模板稀释15倍、Mg2+浓度为0.75 mmol/L、Taq酶用量为1 U、dNTPs浓度为0.2 mmol/L、引物浓度为2 ng/μL效果最佳;选择扩增体系中模板稀释20倍、Mg2+浓度为1.25 mmol/L、Taq酶为1 U、dNTPs浓度为0.225 mmol/L、引物浓度为0.4 ng/μL效果最佳。利用热研5号、奥克雷2个品种对8对引物组合进行筛选,筛选出46对引物组合,为利用AFLP标记对柱花草进行分子生物学研究及分子育种奠定基础。  相似文献   

10.
采用正交试验L16(43)设计,以dNTP、引物和Taq DNA聚合酶3种因素4个水平,并设置了8个模板DNA浓度梯度。扩增效果表明,红麻的SRAP-PCR最佳反应体系为2μL10×Taq Reaction Buffer、20ng模板DNA、dNTP 220μmol/L、引物0.35μmol/L、Taq DNA聚合酶0.5U,总体积为20μL。同时对256对SRAP引物进行扩增,筛选出条带清晰、多态性较好的引物100对。该反应体系及100对多态性引物组合应用于今后红麻的遗传多样性、品种鉴定、亲缘关系、遗传图谱构建、QTL定位等研究。  相似文献   

11.
Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described.  相似文献   

12.
13.
Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.  相似文献   

14.
Health authorities worldwide have consistently recommended the regular consumption of marine fishes and seafood to preserve memory, sustain cognitive functions, and prevent neurodegenerative processes in humans. Shrimp, crabs, lobster, and salmon are of particular interest in the human diet due to their substantial provision of omega-3 fatty acids (n-3/PUFAs) and the antioxidant carotenoid astaxanthin (ASTA). However, the optimal ratio between these nutraceuticals in natural sources is apparently the key factor for maximum protection against most neuro-motor disorders. Therefore, we aimed here to investigate the effects of a long-term supplementation with (n-3)/PUFAs-rich fish oil, ASTA-rich algal biomass, the combination of them, or krill oil (a natural combination of both nutrients) on baseline redox balance and neuro-inflammation indexes in cerebellum and motor cortex of Wistar rats. Significant changes in redox metabolism were only observed upon ASTA supplementation, which reinforce its antioxidant properties with a putative mitochondrial-centered action in rat brain. Krill oil imposed mild astrocyte activation in motor cortex of Wistar rats, although no redox or inflammatory index was concomitantly altered. In summary, there is no experimental evidence that krill oil, fish oil, oralgal biomass (minor variation), drastically change the baseline oxidative conditions or the neuro-inflammatory scenario in neuromotor-associated rat brain regions.  相似文献   

15.
Wheat bran is a composite material made of several layers, such as pericarp, testa and aleurone. It could be fractionated into purified fractions, which might either be used as food ingredients, or serve as a starting material for extraction of bioactive compounds. The aim of this work was to evaluate the potential of using electrostatic separation as a way to obtain purified fractions from wheat bran. Ultrafine-ground bran obtained either by cryogenic grinding or by grinding at ambient temperature was used as starting material. The ultrafine bran was then charged by tribo-electrification and introduced in a chamber containing two high voltage electrodes, where bran particles were separated depending on their acquired charge, allowing positively and negatively charged fractions to be collected separately. The particle size distribution, microstructure and biochemical composition of the obtained fractions were studied. The charge of the particles was influenced by their biochemical composition: particles rich in highly branched and cross-linked arabinoxylans (pericarp) were separated from particles rich in β-glucan, ferulic acid and para-coumaric acid (aleurone cell walls). The testa and the intracellular compounds from aleurone were not highly charged, neither positively nor negatively. The most positively charged fraction represented 34% of the initial bran, and contained 62% of the ferulic acid present in the initial bran. The yield of the separation process was good (5.4% loss), and could be further increased.  相似文献   

16.
Marine organisms represent an excellent source of innovative compounds that have the potential for the development of new drugs. The pharmacokinetics of marine drugs has attracted increasing interest in recent decades due to its effective and potential contribution to the selection of rational dosage recommendations and the optimal use of the therapeutic arsenal. In general, pharmacokinetics studies how drugs change after administration via the processes of absorption, distribution, metabolism, and excretion (ADME). This review provides a summary of the pharmacokinetics studies of marine-derived active compounds, with a particular focus on their ADME. The pharmacokinetics of compounds derived from algae, crustaceans, sea cucumber, fungus, sea urchins, sponges, mollusks, tunicate, and bryozoan is discussed, and the pharmacokinetics data in human experiments are analyzed. In-depth characterization using pharmacokinetics is useful for obtaining information for understanding the molecular basis of pharmacological activity, for correct doses and treatment schemes selection, and for more effective drug application. Thus, an increase in pharmacokinetic research on marine-derived compounds is expected in the near future.  相似文献   

17.
Novel food and non-food uses for sorghum and millets   总被引:4,自引:3,他引:4  
Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.  相似文献   

18.
Pulque is made by fermenting the agave sap or aguamiel of Agave atrovirens with a whole array of microorganisms present in the environment including several lactic acid bacteria and yeasts such as Saccharomyces cerevisiae. Ascorbic acid was determined in pulque and aguamiel, respectively. Phytase activity in lees, liquid and freeze-dried pulque was assayed by measuring the appearance of phosphate from phytate by a colorimetric method likewise phosphate from phytate present in fresh corn tortilla was measured after in vitro incubation with pulque. Iron, zinc, calcium, magnesium and selenium contents were measured in pulque and corn tortilla as well as in nixtamalized corn flour (NCF), the latter is used to make instant tortilla, since corn provides most of the energy as well as most of the phytate in the Mexican rural diet. Pulque showed phytase activity but much less ascorbic acid and iron than previously reported; additionally, phytase in pulque hydrolyzed most of phytate’s corn tortilla. Lees, which is mostly made of pulque’s microbiota, significantly accumulated iron and zinc but no selenium. NCF was fortified with iron by the manufacturers but poorly blended. There were significant differences on selenium content between tortillas samples, apparently some soils in central Mexico are selenium deficient. Moderate pulque intake appears to increase the bioavailability of iron and zinc bound by phytate in corn.  相似文献   

19.
Résumé Fusarium culmorum et, dans une moindre mesure,F. avenaceum, F. sambucinum, Colletotrichum coccodes etCylindrocarpon sp. ont été isolés de tubercules entreposés en atmosphère contr?lée (AC) et atteints de pourriture grave. Des expériences d'inoculation de tubercules avec 10 espèces ou variétés fongiques et conservation en AC à 8 et 10°C ont montré que: 1) les champignons non pathogènes en atmosphère normale (ex.:Cylindrocarpon sp.) le devenaient en AC, 2) ceux qui étaient faiblement pathogènes en atmosphère normale étaient nettement plus virulents en AC (ex.:F. culmorum), 3) les espèces ou variétés virulentes en conditions d'air normales (Fusarium sulphureum etPhoma exigua var.foveata) ne provoquaient pas de pourriture plus grave en AC et leur activité pouvait même être légérement freinée.
Summary The extensive rotting of tubers which occurred during storage trials in controlled atmospheres has led to a mycological and pathological study of the rots. The most frequently isolated species wasFusarium culmorum althoughF. avenaceum, F. Sambucinum, Coletotrichum coccodes and aCylindrocarpon sp. were also present. Tubers of cvs Bintje and Ulla were inoculated with 19 isolates of 10 fungal species or varieties associated with rotting of stored tubers (Table 1). The tubers were incubated at 8 or 10°C in normal or controlled (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2) atmospheres and the extent of rotting was determined a month later (Tables 2 and 3 and Fig. 2). Species which were weakly virulent in a normal atmosphere (variousFusarium spp. andPhoma exigua var.exigua) were clearly more aggressive in the controlled atmosphere and this was especially evident in the case ofF. culmorum. Species ot pathogenic in a normal atmosphere under experimental conditions (Colletotrichum coccodes, Cylindrocarpon sp.,Phoma eupyrena) caused rotting in the controlled atmosphere. The two species which were virulent in a normal atmosphere (F. sulphureum andP. exigua var.foveata) were also virulent in the controlled atmosphere and in some cases the extent of rotting was even less. As a general rule, rotting caused by weakly virulent fungi was greater in both cultivars in the controlled than in a normal atmosphere.

Zusammenfassung Eine starke F?ulnis von in Kontrotrollierter Atmosph?re gelagerten Kartoffelknollen veranlasste eine mykologische und pathologische Untersuchung. Der am h?ufigsten isolierte Pilz warFusarium culmorum. F. avenaceum, F. sambucinum, Colletotrichum coccodes undCylindrocarpon sp. wurden ebenfalls bestimmt. Neunzehn St?mme von 10 Pilzsorten oder-Arten welche bei Lagerf?ulnis vorkommen (Tab. 1) wurden auf Knollen der Sorten Bintje und Ulla inokuliert. Die Lagerung wurde bei 8 oder 10°C under Normalbedingungen oder kontrollierter Atmosph?re durchgeführt (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2). Der F?ulnisgrad (Abb. 1) wurde nach einem Monat bonitiert. Die Ergebnisse sind in den Tabellen 2 und 3 dargestellt und in der Abb. 2 illustriert. Unter in Normalbedingungen nur schwach virulente Arten (verschiedeneFusarien undPhoma exigua var. exigua) waren deutlich aktiver in kontrollierter Atmosph?re. Dies was besonders der Fall fürF. culmorum. Pilze, die im Versuch unter Normalbedingungen nicht pathogen waren (Colletotrichum coccodes, Cylindrocarpon sp., Phoma eupyrena), haben unter kontrollierter Atmosph?re Sch?den verursacht. Hingegen werden die beiden unter Normalbedingungen sehr pathogenen Arten (F. sulphureum undP., exigua var.foveata), durch kontrollierte Atmosph?re wenig beeinflusst. Es wurde sogar in einigen F?llen eine gewisse Verringerung des F?ulnisbefalls beobachtet. Ganz allgemein haben die getesteten kontrollierten Bedingungen die Entwicklung der Pilzf?ulnis an beiden Kartoffelsorten gef?rdert, speziell durch Pilzarten, welche unter Normal-bedingungen wenig Sch?den verursachen.
  相似文献   

20.
Summary Recurrent backcrosses (BC) were used to introduce nuclear factors ofS. tuberosum L. ssp.tuberosum into the cytoplasm of Andean potatoesS. tuberosum ssp.andigena (Juz. and Buk.) Hawkes andS. phureja Juz. and Buk. Each generation BC was produced in reciprocal directions to test the effect of cytoplasmic substitution on yield. This report analyses tuber number, tuber weight, and tuber length of BC2 and BC3 substitution into ssp.andigena cytoplasm and BC2 and BC2 substitutions intoS. phureja cytoplasm. Direction of cross had no consistent significant effect on yield components of ssp.andigena substitution lines. InS. phureja reciprocal progenies direction of cross was responsible for significant differences of some reciprocal sets. When there were significant differences the higher yield usually occurred when ssp.tuberosum was the pistillate parent, but in some progenies when ssp.tuberosum was the pistillate parent the yield was significantly lower than in the reciprocals. It is suggested that differences between reciprocals resulted from chromosomally encoded gene action, resulting from maternal and/or paternal effects, rather than cytoplasmic factors. Authorized for publication as paper No. 7494 in the Journal Series of The Pennsylvania Agriculture Experiment Station.  相似文献   

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