利用“微创刷”法获得抗草甘膦转基因大豆

以发芽3 d的大豆成熟种子胚尖生长点为作用点,利用"微创刷"法将抗草甘膦基因(EPSPS)转入绥农22中,对转化植株T1代进行草甘膦筛选,对筛选后的抗性植株进行PCR检测,得到抗草甘膦转基因大豆。同时研究了不同浓度草甘膦对野生型绥农22与抗草甘膦转基因绥农22大豆植株的影响。结果表明:绥农22 T0代成株率为97.38%,对T1代具有草甘膦抗性的植株进行PCR检测,初步证明EPSPS基因成功转入大豆中,T1代转化效率为6.20%;对野生型绥农22与"微创刷"法获得的转基因绥农22大豆在不同浓度草甘膦进行相关生理指标测定,抗草甘膦转基因绥农22大豆在不同浓度草甘膦作用下叶片叶绿素含量指数、光合速率高于野生型绥农22大豆,莽草酸含量低于野生型绥农22大豆,进一步证明了大豆抗性植株对草甘膦的抗性。     

试纸条法和PCR法检测抗草甘膦转基因大豆的外源基因

分别以转基因抗草甘膦大豆及其受体材料为阳性对照和阴性对照,对喷施除草剂草甘膦后部分存活的5个常规大豆材料后代进行试纸条检测和PCR检测.结果发现2种方法均在被检大豆材料中检测到抗草甘膦基因CP4 EPSPS,而且这2种方法的检测结果能相互验证;对这2种检测技术的应用前景进行了讨论.     

杂草环境下转EPSPS基因大豆NZL06-698的生态适应性研究

为研究转EPSPS基因大豆NZL06-698在杂草环境中的生态适应性,试验设置杂草处理模拟野外环境,研究转基因大豆NZL06-698(GT698)的生存竞争能力以及外源EPSPS蛋白表达情况。结果表明:在相同处理下转基因大豆GT698的株高(R8期)、百粒重显著高于亲本大豆蒙豆12(MD12),但单株产量、单株籽粒数、结实率显著低于亲本大豆,说明外源基因的存在并未增强转基因大豆的生存竞争力,且转基因大豆在野外的生存竞争能力与亲本大豆相比较弱。试验注意到,杂草环境对转EPSPS基因大豆的生长有明显的限制作用,杂草处理下转基因大豆的单株产量、单株籽粒数、百粒重、结实率等指标均显著低于对照处理。ELISA检测结果表明,转基因大豆叶片及籽粒中外源EPSPS蛋白在杂草处理及对照中均正常表达,且两种处理下的EPSPS蛋白表达量无显著差异。以上结果表明杂草环境中转基因大豆的EPSPS蛋白正常表达,正常提供抗草甘膦性状,但是外源基因的存在并没有增加转基因大豆的生存竞争能力,且转基因大豆的生长受到杂草环境的显著抑制,由此得出结论:与亲本大豆相比,转EPSPS基因大豆NZL06-698在野外环境中生态适应能力较弱。     

抗草甘膦转EPSPS大豆的基因漂移研究

以抗草甘膦转EPSPS基因大豆和不同生长类型的非转基因大豆为材料,通过表型筛选及PCR分子检测,分析不同方向和距离条件下转基因大豆中外源基因通过花粉向非转基因大豆的漂移率,为制定转基因大豆安全种植隔离措施提供依据。结果表明,不同生长类型大豆的基因漂移率明显不同,以育成品系ZZH015最高,在70 612株中的漂移率为0.45%;半蔓生地方品种DPZ722次之,164 449株中漂移率为0.01%,而195 088株野生大豆YDD080中没有检测到基因漂移。方差分析表明,漂移率在不同距离和方向条件下均有显著差异,随着距离的增加不断递减。在5 m处漂移率为0.03%,而在29 m处降至0.001%。基因漂移在下风口方向发生较多,表明风媒可能是影响基因漂移分布的重要因素。如果以1%基因漂移率为阈值,无论是自然条件下还是随机选取1 000粒检测,漂移率都低于阈值,表明转EPSPS基因大豆的基因漂移可以忽略不计。     

改良环介导等温扩增技术快速检测转基因大豆

采用改良环介导等温扩增(LAMP)技术,建立一套准确、快速、可靠的用于转基因大豆检测及DNA提取的方法.以CP4-EPSPS外源基因为检测的目的片段,设计内、外引物和环引物,并采用改进的方法提取DNA,进行LAMP扩增,实际检测已知转基因大豆和市售大豆,通过肉眼观察白色沉淀,判断检测结果.改进的DNA提取方法与经典的CTAB方法相比,提取时间至少缩短了1 h,降低了提取成本.环介导等温扩增(LAMP)技术对转基因大豆的检出限为0.01%,是普通PCR方法的20倍.因此,改良的LAMP检测转基因大豆方法灵敏度高,耗时短,方法简便.     

环介导等温扩增技术在转基因作物成分检测中的应用

转基因作物成分检测为农业转基因生物安全管理提供了重要技术支撑.环介导等温扩增(Loop-mediat-ed isothermal amplification,LAMP)技术操作简便、灵敏度高、特异性强,在转基因作物成分检测中得到了广泛应用.本文针对近年来LAMP技术在转基因大豆、玉米和油菜成分检测中的应用情况进行了分析...     

改良Chelex-100法和CTAB法用于转基因抗草甘膦大豆检测效果的比较

以转基因抗草甘膦大豆为研究材料,分别采用改良Chelex-100法和常规CTAB法提取基因组DNA,以提取DNA的浓度和纯度,同时以PCR扩增大豆的内源基因(lectin)及外源特异性序列(CaMV35S,nos,Cp4-epsps)的效果对两种方法进行比较和评价.结果表明:虽然改良Chelex-100法DNA提取纯度不高,但是提取效率与常规CTAB法相当,而且改良Chelex-100法能够快速在1 h之内从大豆中提取DNA,所提取的DNA可以直接用于PCR扩增反应,PCR扩增产物电泳条带清晰.因此,改良Chelex-100法可以替代CTAB法提取DNA用于转基因检测,该方法具有经济、简便、快速的特点.     

利用多重PCR技术快速检测五个转基因大豆品系

转基因大豆305423、MON89788、CV127、GTS40-3-2、356043作为商品化应用最为广泛的大豆品系,种植面积占世界转基因大豆总种植面积的80%以上。根据大豆内标准基因Lectin和5种转基因大豆品系的边界序列设计特异性引物。通过验证引物的适用性、特异性和灵敏度,优化多重PCR检测体系中不同引物的用量及反应退火温度,建立了能同时扩增大豆内源基因Lectin和5个转基因大豆品系的六重PCR检测体系。结果表明:确定的大豆内源基因和5个转基因大豆品系的引物具有很好的特异性,引物之间无交叉扩增和非特异性扩增,多重PCR方法的检测灵敏度达到0.1%。该方法可作为转基因大豆及其产品成分检测的辅助手段,快速检测转基因大豆及其产品中的相应品系。     

小麦内源基因 GAG56D的快速检测技术体系

为了满足转基因小麦检测中对内源参照基因的检测要求,以小麦属特异的内源基因γ-醇溶蛋白基因（ GAG56D）作为目的基因,采用环状等温扩增技术(LAMP)建立了小麦内源基因 GAG56D的快速检测技术体系。针对小麦内源基因 GAG56D特异靶序列的6个区域设计4 条特异性引物,通过显色法进行LAMP检测,并对时间、温度等反应条件及反应灵敏度、特异性、稳定性进行探索。结果表明,该检测体系最适反应温度为63℃,反应时间 60 min,定性检测低限达到0.5%（w/w）。该检测方法具有高度的特异性、灵敏度和稳定性,操作简单、快速。     

耐除草剂转基因大豆对花粉生活力的影响

转基因作物的环境安全评价是其商业化推广前的必要环节,其基因漂移风险及其可能引起的生态环境效应是安全性评价的重要内容。为了明确转EPSPS、PAT基因抗草甘膦大豆S4003. 12和S4003. 14外源基因的逃逸风险,于大豆盛花期选取温室种植的转基因大豆、其受体品种及常规栽培大豆材料花粉,使用液体培养基培养,检测其萌发率,并于带标尺显微镜下观察其花粉粒直径。结果表明:大豆花粉刚离体后萌发活力最强,培养2 h后花粉萌发率基本达到最大值约88. 2%,随离体时间延长萌发活力随之下降,室温放置3 h后,花粉几近完全失活;与非转基因对照相比,转EPSPS、PAT基因耐除草剂大豆S4003. 12和S4003. 14的花粉离体后的生存能力无显著差异,对花粉粒直径大小无显著差异。研究表明耐除草剂转基因大豆花粉传播能力与非转基因大豆间无显著差异,通过设置隔离区可有效规避外源基因逃逸风险。     

Comparative Assessment of the Efficacy of Various Nitrogen Fertilizers

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.     

Studies on natural repellents against potato tuber moth (Phthorimaea operculella Zeller) in country stores

Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.     

Mineral composition of some traditional Mexican teas

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.     

Novel food and non-food uses for sorghum and millets

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.     

In vitro antimicrobial activity of different accessions ofSolanum commersonii Dun. from Uruguay

Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds.     

Extreme resistance to infection by potato virus X in genotypes of wild tuber-bearingSolanum species

Summary Clones derived from thirty-one different accessions (nineteen of Argentine origin) belonging to eightSolanum species were screened for resistance to infection by potato virus X strain cp (PVX cp) by mechanical inoculation of plantlets that had been micropropagated in vitro. Estimates of PVX multiplication obtained by enzyme linked immunosorbent assay and slot blot nucleic acid hybridization allowed the identification of resistant clones derived from five accessions belonging toS. commersonii S. oplocense, S. sparsipilum andS. tuberosum andigena. Resistant genotypes supported PVX concentrations 5 to 15 times smaller than did the susceptible control cultivar Spunta. Graft inoculation test confirmed the presence of extreme resistance similar to that conferred by the ‘immunity’ gene X¹ (also called RX_act).     

Cyanobacteria Secondary Metabolites as Biotechnological Ingredients in Natural Anti-Aging Cosmetics: Potential to Overcome Hyperpigmentation,Loss of Skin Density and UV Radiation-Deleterious Effects

The loss of density and elasticity, the appearance of wrinkles and hyperpigmentation are among the first noticeable signs of skin aging. Beyond UV radiation and oxidative stress, matrix metalloproteinases (MMPs) assume a preponderant role in the process, since their deregulation results in the degradation of most extracellular matrix components. In this survey, four cyanobacteria strains were explored for their capacity to produce secondary metabolites with biotechnological potential for use in anti-aging formulations. Leptolyngbya boryana LEGE 15486 and Cephalothrix lacustris LEGE 15493 from freshwater ecosystems, and Leptolyngbya cf. ectocarpi LEGE 11479 and Nodosilinea nodulosa LEGE 06104 from marine habitats were sequentially extracted with acetone and water, and extracts were analyzed for their toxicity in cell lines with key roles in the skin context (HaCAT, 3T3L1, and hCMEC). The non-toxic extracts were chemically characterized in terms of proteins, carotenoids, phenols, and chlorophyll a, and their anti-aging potential was explored through their ability to scavenge the physiological free radical superoxide anion radical (O₂^•−), to reduce the activity of the MMPs elastase and hyaluronidase, to inhibit tyrosinase and thus avoid melanin production, and to block UV-B radiation (sun protection factor, SPF). Leptolyngbya species stood out for anti-aging purposes: L. boryana LEGE 15486 presented a remarkable SPF of 19 (at 200 µg/mL), being among the best species regarding O₂^•− scavenging, (IC₅₀ = 99.50 µg/mL) and also being able to inhibit tyrosinase (IC₂₅ = 784 µg/mL), proving to be promising against UV-induced skin-aging; L. ectocarpi LEGE 11479 was more efficient in inhibiting MMPs (hyaluronidase, IC₅₀ = 863 µg/mL; elastase, IC₅₀ = 391 µg/mL), thus being the choice to retard dermal density loss. Principal component analysis (PCA) of the data allowed the grouping of extracts into three groups, according to their chemical composition; the correlation of carotenoids and chlorophyll a with MMPs activity (p < 0.01), O₂^•− scavenging with phenolic compounds (p < 0.01), and phycocyanin and allophycocyanin with SPF, pointing to these compounds in particular as responsible for UV-B blockage. This original survey explores, for the first time, the biotechnological potential of these cyanobacteria strains in the field of skin aging, demonstrating the promising, innovative, and multifactorial nature of these microorganisms.     

Marine Pharmacology in 2009–2011: Marine Compounds with Antibacterial,Antidiabetic, Antifungal,Anti-Inflammatory,Antiprotozoal, Antituberculosis,and Antiviral Activities; Affecting the Immune and Nervous Systems,and other Miscellaneous Mechanisms of Action ?

The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories.