黄连抗氧化活性研究

利用DPPH、FRAP和ABTS三种抗氧化活性分析方法对黄连植物不同部位的有机溶剂提取部分进行抗氧化评价,将所测定结果与Trolox进行比较,发现黄连植物不同部位抗氧化活性不同。其中,黄连须根的抗氧化活性最高;同一部位中,乙酸乙酯和甲醇提取物抗氧化活性一般要高于石油醚提取物。在三种方法中,黄连不同部位的提取物清除自由基的能力均随浓度增大而增大;三种方法之间有很好的相关性,以FRAP法与DPPH法相关性最好(r=0.9261,P<0.01)。     

明胶/纳米SiO2复合膜的体外抑菌试验

本实验测定了明胶、纳米SiO2、明胶/纳米SiO2复合膜对6种供试菌的抑菌效果,结果表明,明胶不具有抑菌作用;纳米SiO2对供试菌具有较好的抑茵效果;20种明胶/纳米SiO2复合膜材料中,有11种复合膜对供试菌具有较强的抑菌效果.用琼脂平板稀释法测定了具有较强抑菌作用复合膜的最低抑菌浓度(MIC),结果表明,最低抑菌浓度因膜的配比和菌种类型的不同而有所差异,为16.0 mg/mL～256.0 mg/mL.复合膜对蜡样芽孢杆菌的最低抑菌浓度(MIC)最大(256.0 mg/mL),而对其他供试菌相对较低,为64.0 mg/mL～128.0 mg/mL.     

磁化水浸种对西瓜种子萌发及幼苗生理的影响

用不同强度的磁化水(0．05T、0．08T、0．10T、0．15T)浸种西瓜种子研究磁化水对西瓜种子萌发及幼苗生理的影响,结果表明：与对照相比,各种强度磁化水浸种都能提高种子的发芽率、发芽势、发芽指数和幼苗的抗坏血酸含量,其中0．10T磁化水处理后西瓜种子发芽率、发芽势提高幅度最大;对抗坏血酸含量的影响以0．08T处理最明显;经过不同强度磁化水处理后幼苗中的过氧化物酶同工酶酶、酯酶同工酶活性得到不同强度的增强,不同品种表现不同。实验结果说明磁化水处理后能明显提高西瓜种子的萌发能力,并能提高幼苗的各种生理活性。     

长叶榧黄酮类化合物含量及成分分析

对长叶榧不同营养器官和不同居群的3种营养器官黄酮类化合物含量进行测定,并利用聚酰胺薄层层析法对黄酮类化合物的成分进行分析。结果表明：（1）长叶榧各个营养器官均含有黄酮类化合物,其含量高低顺序依次是一年生叶>一年生枝>幼根>老根>树皮>老枝>茎;（2）长叶榧不同营养器官其黄酮类化合物的种类有很大的差异,以一年生叶、一年生枝最多,幼根次之,老根、老枝第三,树皮、茎最少;（3）不同长叶榧居群3种营养器官黄酮类化合物含量各不相同,但均以一年生叶最高,一年生枝次之,老枝最低;（4）不同长叶榧居群一年生叶黄酮类化合物含量差异不显著,一年生枝、老枝差异较大;（5）不同长叶榧居群3种营养器官其黄酮类化合物的种类在一年生叶中没有差异,一年生枝中差异较小,老枝中差异较大。     

红豆杉细胞培养生产紫杉醇产量稳定性的探讨

通过磷酸盐双饥饿和秋水仙碱这两种经典的同步化方法处理悬浮培养的红豆杉细胞 ,以实现培养物的均一性 ,并比较了同步化与非同步化细胞及不同同步化方法处理的细胞紫杉醇产量。结果表明 ,不同同步化方法处理的细胞紫杉醇产量有差异 :秋水仙碱同步处理处于中期的细胞紫杉醇产量高于非同步化细胞 ,而磷酸盐双饥饿同步处理处于间期的细胞紫杉醇产量则相反。这表明紫杉醇产量与培养物的均一性有关 ,且与细胞同步的周期时相有关 ,采用同步化方法来选择合适的细胞周期时相有利于紫杉醇产量的稳定 ,通过比较不同同步化方法处理对细胞生物量和 POD活性的影响进一步探讨紫杉醇产量产生差异的原因     

辣椒花药培养的胚状体分化及其与成苗率的关系

12个辣椒品种的花药培养的结果表明,所有品种均可诱导出胚状体,其中9个品种可获得健壮的再生植株。每一辣椒品种的适宜植物生长调节利配比不同。不同品种的胚状体诱导率和成苗率有差异。成熟的胚状体均能分化成苗,根先分化或停止发育的胚状体很少成苗。     

一株细菌儿茶酚型铁载体分泌的影响因素研究

采用两种新的高分辨率的薄层层析（TLC）方法对一株土壤细菌S1在3种不同培养基上产生的儿茶酚型铁载体进行了分析。结果表明：不同培养基对铁载体的产生影响较大,在3种不同的培养基上菌株S1产生不同的儿茶酚铁载体,其中仅在1种培养基上S1能够分泌2,3-二羟基苯甲酸（2,3-DHBA）。同时,还分析了Al^3＋对S1分泌的儿茶酚型铁载体总量的影响,结果表明：Al^3＋能显著刺激铁载体的分泌,并且能抵消一定浓度范围内的Fe^2＋对铁载体分泌的抑制作用,KMB培养液中产生的4种儿茶酚铁载体中有3种和Al^3＋有较强的螯合力．     

高寒区10种青藓科植物茎结构的生态适应性

该研究对新疆天山一号冰川地区的10种青藓科植物茎的解剖结构进行了光镜和扫描电镜观察。结果表明:它们的茎横切面形状不同,表皮细胞均为1层,内、外皮部分化明显,细胞壁由外向内逐渐变薄,中轴分化明显,所占茎面积的比例、细胞厚度以及大小都不尽相同,大多数种类的细胞壁具有角隅加厚的现象。当茎干时,细胞壁表面的凹陷程度不同,其上具有不同形状的纹饰及附属物,大多数种类的表面有深浅和大小不一的小窝点分布。这些特征在不同属及不同种之间均有差异,反应出对环境的适应性,可作为青藓科植物潜在的分类依据。     

Epidemiological Differentiation of Serratia marcescens: Typing by Bacteriocin Sensitivity

Strains of Serratia marcescens were compared and differentiated by a new method. Bacteriocin lysates were prepared from mitomycin-induced S. marcescens and added to lawns of test strains. From 100 bacteriocin producers, 12 were chosen with the aid of computer analysis as the most useful in differentiation. Uniform drops of the 12 standard bacteriocins were added simultaneously with a bacteriocin-bacteriophage dropper to each strain to be typed. All 93 strains of S. marcescens tested were typable and were differentiated into 79 different sensitivity patterns. One pattern had three strains, 12 patterns had two strains each, and 66 patterns had only one strain. The bacteriocins also inhibited Shigella, Klebsiella, and Enterobacter, but no other Enterobacteriaceae. Bacteriocin sensitivity was less stable as an epidemiological marker than bacteriocin production. Several colonial mutants had sensitivity patterns different from the wild types, but most mutants were identical. In three different instances when cross-infection had been shown by other methods, bacteriocin sensitivity also gave the correct epidemiological results. Until the significance and frequency of genetic variations are known, a more stable epidemiological technique should be used in conjunction with bacteriocin sensitivity.     

K、Na、Ca、Mg 4种元素在疏叶骆驼刺体内含量分布特点的研究

 此项工作在新疆平原荒漠区盐化草甸带进行。研究结果显示出K、Na、Ca、Mg 4种元素在植物体内不同器官的含量分布特点和各个器官中不同元素间的含量关系。同时表明这4种元素在植物体不同器官中具有不同的作用。对于K、Na元素,地上部器官尤其叶片中含量水平反映出器官具有较强的留K排Ns的选择性元素的分配机制。     

Physiological and biochemical changes in Calanus hyperboreus from Jones Sound NWT during the transition from summer feeding to overwintering condition

Summary Several biochemical and physiological characteristics of stage V and female adult Calanus hyperboreus from two different depth ranges (0–50 m and 200–500 m) were compared at a time near the peak of the summer pelagic algal bloom in Jones Sound, and again one month later, when the near surface chlorophyll levels were low and most copepods had migrated to their overwintering dephts. For a given stage deep water animals were larger and had higher total lipid levels than did surface animals. Feeding activities, as evidenced by gut pigment contents, may be lower in animals at depth, although potential digestive activities, as expressed in the levels of three digestive enzymes, were not very different either in different stages or at different depths. Respiration rates in animals that had migrated down for the winter were not much lower than in those at the surface although energetic considerations suggest that they may decrease later. Ammonia excretion rates however, changed dramatically. Surface, feeding animals had the highest rates and deep water animals in September had undetectably (<1 ng atom ammonia nitrogen animal^-1 · day^-1) low rates.     

原子力显微镜下丝素纤维及丝素蛋白的形态结构研究

利用原子力显微镜(AFM)、透射电镜(TEM)、圆二色谱仪(CD)等手段,研究了家蚕丝素纤维及丝素蛋白的形态结构,并尝试通过改变丝素蛋白溶液的酸碱性来观测其形态变化。结果表明,丝素纤维表面有许多沟槽和条纹,具有原纤结构特征;许多直径为20～50nm的圆形或椭圆形颗粒分子形成丝素蛋白的微观形态。在不同的酸碱条件下,球状颗粒分子具有不同的聚集方式,形成不同的微观形态。     

Fe2+、Cu2+、Zn2+对植物生理特性影响的比较分析

以浸水处理为对照系统分析了Fe2+、Cu2+、Zn2+等金属离子对植物胁迫损伤相关的7个生理指标,并应用数理统计学和生物化学的相关原理和方法从氧自由基伤害的角度比较分析了这三种离子处理对植物生理特性的影响。结果表明:不同离子处理由于对植物造成的胁迫损伤不同,因而它们对植物生理特性的影响效应也有明显差异,并且这种差异与其所处理的离子胁迫性质间存在显著的关联性。     

An evolutionary modelling approach to understanding the factors behind plant invasiveness and community susceptibility to invasion

Ecologists have had limited success in understanding which introduced species may become invasive. An evolutionary model is used to investigate which traits are associated with invasiveness. Translocation experiments were simulated in which species were moved into similar but evolutionarily younger communities. The main findings were that species that had previously been the most abundant in their original communities have significantly higher rates of establishment than did species that had previously occurred at low abundance in their original community. However, if establishment did occur, previously abundant and previously low-abundant species were equally likely to become dominant and were equally likely to exclude other species from their new community. There was a suggestion that the species that were most likely to establish and exclude others were 'genetically' different. When species that had evolved in different simulations (but with identical environmental conditions) were transplanted into communities that had also evolved in different simulations of the same conditions, the outcomes were difficult to predict. Observed rates of establishment and subsequent competitive dominance were observed to be species- and community combination-specific. This evolutionary study represents a novel in silico attempt to tackle invasiveness in an experimental framework and may provide a new methodology for tackling these issues.     

‘哲引3号’ב北京杨’杂交子代悬浮细胞系的建立和植株再生

采用“固—液—液—固”培养方法,分别以［‘哲引3号杨’（Populus pseudo-simonii×P.nigra ‘Zhenyin3#’）ב北京杨’（P.×beijingensis）］杂交子代的种子、子叶和下胚轴为材料,开展了多个杂交子代悬浮细胞系建立和培养研究,结果显示：（1）不同基因型的种子愈伤诱导率差异显著,不同基因型的子叶、下胚轴愈伤诱导率差异不显著;不同基因型的初始悬浮细胞系密实体积差异均显著。（2）采用静置分层和细胞筛双层过滤结合的方法能把游离胚性细胞从初始悬浮细胞系中分离出来,不同基因型来源的游离胚性细胞数量差异不显著。（3）种子和子叶来源的胚性悬浮细胞系能在不含NH+4的液体培养基中诱导出球形愈伤,这些愈伤薄片能在含有CPPU的分化培养基上实现植株再生,最后共获得了20个基因型的来自种子球形愈伤的再生植株和另外20个基因型的来自子叶球形愈伤的再生植株。     

Resistance to heavy metals in different strains of Thiobacillus ferrooxidans

Ten different isolates of Thiobacillus ferrooxidans were studied with regard to their degree of resistance to the metals copper, nickel, uranium, and thorium. Inhibitory concentrations for a particular metal were those which showed a statistically-significant decrease in the amount of ferrous iron oxidized by the bacterium compared to an untreated control. The different isolates had different susceptibilities to the metals tested, and none of the metals had a stimulatory effect. Uranium and thorium were 20 to 40 times more toxic to ferrous iron oxidation than either copper or nickel.     

Factors Affecting Reproducibility of Numerical Classifications

Results obtained with reference organisms which had been included in each of three different investigations were compared. Positions of the reference organisms in diagrams based on highest-link numerical groupings varied with the composition of the microbial samples studied, but significant correlations were found between the results of different investigations. Correlations between the overall groupings obtained in different studies were often better than the correlations between actual similarity values computed between specific pairs of organisms. Similarity values based on different sets of features showed significant correlations, regardless of the kinds of features involved or of the number of features (above a minimum of about 40). Correlations between values based on totally different features were nearly as good as those between values based on similar features which had been determined by different investigators.     

不同萝卜品种游离小孢子的诱导及培养体系优化研究

以19个萝卜品种为试验材料,研究各种因素对萝卜游离小孢子培养的影响.结果表明:(1)13个品种可诱导出胚状体,诱导率达到68.4%,但不同品种间产胚量存在较大差异,其中路路通翠雪产胚量可达每蕾10个,而圆白萝卜的产胚量最小为每蕾0.125个,进一步培养有8个品种得到再生植株;(2)在NLN-13液体培养基中添加活性炭和6-BA对萝卜游离小孢子出胚有较好的促进作用,小孢子分离30d后将胚状体转移至固体MS培养基上,子叶型胚可获得大量的再生植株,而畸形胚状体转移后不能获得正常的再生植株.     

枇杷花主要有效成分的含量

采用紫外分光光度法及高效液相色谱法,研究不同产地不同年份的枇杷花总黄酮和三萜化合物的差异,以确定其含量较高的产地及年际变化情况。结果表明:同一年份不同产地枇杷花中总黄酮和三萜化合物含量有显著差异,龙泉、仁寿、攀枝花及莆田总黄酮含量显著高于其它产地(P<0.01),齐墩果酸以龙泉、仁寿、浦江和莆田四地较高,并显著高于遂宁和内江等地(P<0.05或P≤0.01),熊果酸含量最高的产地为浙江余杭,其含量显著高于遂宁、攀枝花、壁山等地(P<0.01)。同一产地不同年份样品中总黄酮和三萜化合物含量变化较小。与地理、气候因子进行相关性分析,表明齐墩果酸与纬度、经度有一定相关性,而其它成分的相关性不大。     

长江口湿地三个演替阶段大型底栖动物群落特征

2001—2005年对长江口新生沙洲九段沙(上沙、中沙、下沙)盐沼演替序列不同阶段[盐渍藻类阶段(SA)、海三棱草(Scirpusmariqueter)—草(Scirpustriqueter)阶段(MT)、芦苇(Phragmitesaus-tralis)—互花米草(Spartinaalterniflora)阶段(AA)]的大型底栖动物群落特征进行了分析研究。大型底栖动物群落的物种数、Shannon-Wiener多样性指数、Pielou均匀度指数、密度及生物量都是MT>AA>SA。SA、AA优势种的生活型分别是底内型、穴居型;MT优势种的生活型是底上附着型和穴居型。不同沙洲相同盐沼演替阶段大型底栖动物群落结构都较为相似,盐渍藻类阶段的相似性最高;不同演替阶段间差别明显,SA和AA间差别最大。不同盐沼演替阶段大型底栖动物群落特征的明显差异,既反映了环境沿盐沼演替序列的梯度变化,也体现了不同盐沼对底栖动物群落作用的差别,同时也显示了大型底栖动物对不同盐沼演替阶段生境的适应。