荧光假单胞菌岩藻多糖酶的生产和酶学性质研究

[目的]研究了荧光假单胞菌HNTO1液态发酵产岩藻多糖酶的条件,并对酶学性质进行初步探索。[方法]采用单因子试验。[结果]HNT01产酶的最适培养基组成为：海带粉2%、尿素2%、葡萄糖0.06%、磷酸氢二钾0.1%,发酵起始pH值6.0,250 ml三角瓶装液量为100 ml,30℃、160 r/min条件下培养76 h。该菌所产岩藻多糖酶最适反应温度为50℃,最适反应pH值为6.0。[结论]为进一步开发高附加值的褐藻类保健食品和医药产品提供必要的科学基础。     

苏皖鲁豫麦田小麦孢囊线虫调查以及rDNA ITS序列特征分析

为给小麦孢囊线虫综合治理提供一定的理论依据,通过对苏皖鲁豫接壤地区30块田的调查和分析,探讨了这些地区麦田小麦孢囊线虫的发生情况及线虫群体之间亲缘关系。结果表明,采集的30份样品中都能检测到孢囊线虫,孢囊密度为每100g土壤1～80个。进一步对30个小麦孢囊线虫群体的rDNA-ITS区PCR扩增、测序,对其序列进行比较分析发现,30个分离物的核苷酸序列同源性为97.1%～100%,与已报道的中国菌株（AY148382,EU106175）、澳大利亚菌株（AY148395）和俄罗斯菌株（AY148351）群体的进化关系最为接近,且位于进化树的同一个分枝,都属于禾谷孢囊线虫Avenae组。     

Study of a germplasm collection of loquat (Eriobotrya japonica Lindl.) by multivariate analysis

Loquat species (Eriobotrya japonica Lindl.) originated in China, later was introduced in Japan. However, introduction in Europe occurred much later, in 18th century, it was introduced as an ornamental tree. Since then, the species was very well adapted to the Mediterranean climate, mainly in South East of Spain, where is located more than 50% of total European crop production. A European Project titled ‘Conservation, evaluation and collection of underutilized fruit species’ supported surveys and collection of plant material from these species in the Mediterranean basin countries. One of these surveys resulted in a germplasm collection of loquat established at IVIA, Valencia, Spain. This collection is being extended with new accessions collected across the world, currently the collection have 123 accessions under study. Germplasm management needs first a characterization of the plant material introduced and second diversity studies into the collection that could point out the variability pattern, to establish groups of accessions with similar traits and the most significant variables. These results allow organizing the information gathered for further uses. In this paper, 62 accessions from the IVIA germplasm collection were studied. Results from 43 variables were gathered and data studied by multivariate analysis. The analysis allowed summarizing the data tables with new variables containing most of the information. These results along with those obtained in the coming years will allow define a nuclear collection (minimum number of accessions that contained all the variability present in the collection).     

贵州猪、牛志贺样毒素大肠杆菌的检出与鉴定

以两对全盛的寡核苷酸引物,通过聚合酶链式反应,检测158份猪和牛腹泻粪便分离物,从8份猪源和3份牛源分离物中扩增出大肠杆菌志贺样毒素基因片段,其生化试验符合大肠杆菌特征,经Vero细胞检测均产生志贺样毒素,血清学试验证实分属不同的血清型,与志贺样毒素大肠杆菌血清型范围相符。     

Industrial utilization of tobacco stalks II: preparation and characterization of tobacco pulp by steam explosion pulping

Our previous paper showed tobacco stalks to posses the characteristics of a raw material for pulp and paper application. It contains the major biomass constituents and cell components common to wood species. In this study, preparation and characterization of tobacco stalk pulp by steam explosion (SE) pulping at two chemical pretreatments were attempted. Chemical pretreatment prior to SE pulping improved the brightness, yield, and strength properties of the resulting tobacco SE pulps in the order: 6% Na₂SO₃ + 1% NaOH > 6% Na₂SO₃ > control (untreated). The 6% Na₂SO₃ + 1% NaOH-impregnated tobacco stalks produced SE pulps of good fiber length distribution and considerable properties that compare well with pulps from other raw materials obtained from previous studies, and the nonimpregnated ones showed strength properties superior to those of their poplar counterpart. Prior to bleaching, pretreating the tobacco stalk SE pulps with two stages, 2% NaOH at 90°C, improved the initial pulp brightness by about 5 points. Two-stage 6% H₂O₂ bleaching gave a comparable effect with hypochlorite bleaching for both tobacco and poplar, giving a 29–34 brightness point increase for tobacco SE pulp and 61 for the poplar samples. The differences in the bleaching responses for untreated tobacco and poplar SE pulps were attributed to the differences in their lignin structure, as shown in the total yield of their respective nitrobenzene oxidation products and FT-IR spectra. Tobacco SE pulps contain more of the guaiacyl-type lignin and poplar the syringyl-type lignin.This paper was presented in part during the 1998 CORESTA (Cooperation Centre for Scientific Research Relative to Tobacco) Congress, Brighton, UK, October 1998     

高等农业教育的特色化

高等农业教育的特色化是指高等农业教育在办学过程中对那些适应社会经济发展需要 ,符合教育规律 ,利于自身生存与发展的独特之处的自觉追求。本文在分析高等农业教育特色化发展的必然性基础上 ,提出高等农业教育应围绕生命学科彰显特色的观点     

棉花WD40基因的克隆及生物信息学分析(英文)

A pair of PCR primers was designed based on the conserved sequences of WD40 family gene of different varieties.The normolization library was screened by PCR methods,the cDNA insert size of positive clones were analyzed by PCR method.A full-length cDNA of WD40(GenBank accession number:EU219610)in cotton was obtained from sequencing.This gene is 1 796 bp in length,containing an open reading frame encoding 274 amino acids and a stop codon from 35th to 860th position.The bioinformatics characterization indicates that the protein is encoded by WD40 domain.pI and molecular weight of the protein encoded were predicted to be 4.24 and 29 kDa,respectively.The yielded gene was accondingly named as GDRP1.RT-PCR analysis showed that the expression of GDRP1 varied during the gland formation process.These results will be helpful for our further study on the gland formation of cotton.     

白银市土壤多环芳烃污染特征

选取甘肃省白银市为研究区域,采集23个具有代表性的不同功能区表层土壤样品,分析土壤样品中美国环保署规定的16种优控多环芳烃（PAHs）的含量和组分特征,并采用同分异构体比率研究其污染来源。研究表明,该区土壤中PAHs含量为64.96～3 043.86ng/g,远超出土壤内源性PAHs含量,有52.2%、13.0%和21.7%的土壤样品分别达到PAHs的轻度、中度、重度污染水平。多环芳烃浓度在不同类型土壤中的含量由高到低依次为河流下游底泥〉生活区〉工业生产区〉污灌区。白银市土壤样品中4环及4环以上高分子量的PAHs所占比例较大。源解析结果表明,该市土壤PAHs来源主要是木材、煤的燃烧和化石燃料的燃烧。     

The fowl adenovirus (Fadv-11) outbreak in Iranian broiler chicken farms: The first full genome characterization and phylogenetic analysis

Fowl adenoviruses D and E (FAdV-D and E) can cause inclusion body hepatitis (IBH) in commercial chicken flocks. Recently, IBH outbreaks have been increasingly reported in different regions of Iran, particularly in broiler farms. The present study was conducted to perform, for the first time, a complete genome characterization of a FAdV isolate from an IBH outbreak in Iran. Briefly, liver samples were collected from affected broiler flocks and following viral DNA extraction and confirming by PCR technique; one positive sample was selected from an affected flock to conduct a complete genome sequencing. The current FAdV, named "Fowl_Adenovirus_D_isolate_iran/UT-Kiaee_2018", was placed into FAdV-11 serotype (D species). According to the complete genome sequence analysis, UT-Kiaee had high homology with Chinese and Canadian FAdV. The partial sequence of the hexon gene revealed that UT-Kiaee shared 100% identity with previous Iranian FAdVs. The present study was the first to report full genome FAdV in Iran and complete the puzzle of molecular epidemiology of FAdV in Iran through determining the possible origin of Iranian FAdvs, which are the causative agents of recent IBH outbreaks in Iran.     

轮纹大茎点菌葡糖淀粉酶部分酶学性质研究

轮纹大茎点菌在液体培养条件下产葡糖淀粉酶酶活很低,而在固态培养条件下酶活相对较高。对粗酶液中葡糖淀粉酶的部分酶学性质进行研究,结果表明,该酶的最适反应温度为50℃,30~50℃之间有较高活性;40℃以下稳定,50℃保温1 h酶活性损失60%以上。酶的最适pH为8.0,在pH 7.0~11.0之间有较高的酶活性:pH 5.0以下酶不稳定,活性迅速丧失,5.0~10.0之间酶相对稳定。K+、Fe2+、Ca2+对酶的活性基本没有影响,而Cu2+、Mg2+、Zn2+、Mn2+、Na+对酶的催化活性有激活作用,其中Mn2+激活作用最为强烈。