稀土金属镧(III)用于配位氧化控制降解寡糖的分子量分布与抗氧活性

在壳聚糖溶液中加入镧离子使形成壳聚糖镧(III)配合物,用H2O2对形成的壳聚糖La(III)配合物进行氧化降解,测定了降解产物的分子量分布.结果表明壳聚糖镧配合物在过氧化氢的存在下降解迅速,降解从大分子量范围开始,降解产物寡糖分子量分布窄于目前通用方法.分布指数与寡糖的平均数均分子量有关,分子量在10个糖以上时,DP越小,分布指数越小.同时对壳聚糖、壳聚糖镧配合物进行了清除O2-自由基的对比研究,发现壳聚糖镧配合物清除O2-自由基活性高于壳聚糖自身.     

壳聚糖铁(Ⅲ)配合物的合成及结构表征

【研究目的】为了利用高分子壳聚糖的生物活性,寻找理想的补铁制品,在均相反应条件下,以壳聚糖为载体与Fe3+离子配位,合成了壳聚糖铁(Ⅲ)配合物;【方法】用元素分析、UV光谱和IR光谱等研究了配合物的组成与性质,并优化了配合物的合成条件;【结果】壳聚糖对Fe3+的吸附具有较好的动力学性能,随着温度的升高,反应达到平衡的时间缩短;壳聚糖对Fe3+离子吸附等温线符合Langmuir吸附等温线方程,在室温下,pH为1.8时吸附8h的饱和吸附量Qmax = 62.89mg/g,b =4.969J/mg;壳聚糖铁(Ⅲ)配合物的UV光谱中出现了新的吸收峰,IR光谱分析显示,形成配合物后,壳聚糖的部分特征吸收峰也发生了一定的位移,光谱分析的结果表明壳聚糖与Fe3+离子之间可能发生了配位反应;壳聚糖中主要是-NH2和-OH参与了与金属离子的配位,部分乙酰氨基(-CONH2)也可能参与了配位。【结论】实验结果有望使壳聚糖铁(Ⅲ)配合物成为一种具有较好生物利用度的营养型补铁剂,使壳聚糖铁(Ⅲ)配合物成为具有多功能的保健药品。     

氨基寡糖素农药产品登记情况分析

<正>一、氨基寡糖素简介氨基寡糖素,也称为农业专用壳寡糖,是从海洋生物如虾类、蟹类等的外壳提取而来的多糖类天然产物,指D-氨基葡萄糖以β-1.4糖苷键连接的低聚糖,由几丁质降解得壳聚糖后再降解制得,或由微生物发酵提取的低毒杀菌剂。作为一种新型的生物农药,氨基寡糖素不同于传统农药,它不直接作用于有害生物,而是通过激发植物自身的免     

鱿鱼内脏制备功能性短肽的初步研究

为了选取水解鱿鱼内脏效果较优的蛋白酶,并对鱿鱼内脏的水解液进行分析,测定水解液的分子量分布范围,并对洗脱液的DPPH自由基清除能力进行分析。试验选取碱性蛋白酶、中性蛋白酶、胰蛋白酶、动物蛋白酶、风味蛋白酶、木瓜蛋白酶对鱿鱼内脏进行水解,通过测定水解液的总氮含量、氨基态氮含量,比较各水解液的水解度、氮收率以及水解得率。经大孔树脂对胰蛋白酶水解液进行水、20%、60%、80%甲醇-水梯度洗脱,经液相质谱(LC-MS)进行分析。结果发现水解液短肽分子量范围在100~2400,其中以60%梯度洗脱的水解液分子量分布范围较为集中,且以分子量在200左右的化合物为主,对各洗脱梯度水解液的1,1-二苯基-2-三硝基苯肼(DPPH)自由基清除能力分析可知60%梯度洗脱水解液DPPH清除能力为40.21%。胰蛋白酶为水解鱿鱼内脏较优的蛋白酶,且60%甲醇-水为最优洗脱浓度。     

壳聚糖和壳寡糖保鲜湖北利川山药的研究

为了延长湖北利川山药的保鲜期,以壳聚糖和壳寡糖为原料,添加甘油、乙酸等配制保鲜液,对利川山药进行浸渍沥干处理后,于10℃培养箱中贮藏,并测定贮藏过程中的失质量率、褐变率、腐烂率、维C含量、多酚氧化酶(PPO)活性等指标。结果表明,壳聚糖和壳寡糖可以在不同程度上抑制山药失质量率、褐变率、腐烂率的上升;延缓维C含量下降;在测定PPO时发现,3组试验组酶活力均是先上升达到峰值后下降,其中空白组在第4天达到峰值,而壳聚糖和壳寡糖处理的样品在第6天达到峰值,且空白组的酶活力始终高于壳聚糖组和壳寡糖组。由此说明,壳聚糖及其降解产物壳寡糖在利川山药的保鲜方面具有可观的应用前景。     

海带褐藻糖胶的分离纯化及其抗氧化活性测定

为更好地开发海带资源,分别采用DEAE-Sepharose FF弱阴离子交换柱层析、高效液相凝胶色谱对海带褐藻糖胶粗品进行分离纯化,结果表明,2种方法均可用于褐藻糖胶的分离,均分离出3个组分,离子交换层析分离出的组分命名为D-1,D-2,D-3。高效液相凝胶色谱分离的3种组分命名为H-1,H-2,H-3,其分子量分别为193.148,74.407,44.452 kD。对D-1,D-2,D-33种组分进行抗氧化活性测定,3种组分对DPPH自由基和·OH均表现出一定的清除能力,且分子量越小,清除自由基能力越强,体外抗氧化活性越好。     

不同分子量壳寡糖对黑麦草种子萌发和幼苗抗病酶活性影响的研究

采用平均分子量分别为3000、5000、10000的0.3%(w/v)壳寡糖溶液处理黑麦草种子并对处理过的种子进行发芽试验和幼苗抗病酶活性的测定。结果表明:三种不同分子量壳寡糖溶液处理黑麦草种子,均可以提高黑麦草种子的发芽率、发芽指数和活力指数,并且提高了幼苗的叶绿素、可溶性蛋白的含量。增强了幼苗的过氧化物酶(POD)活性,诱导了病程相关蛋白(即,几丁质酶和β-1,3-葡聚糖酶及苯丙氨酸解氨酶)的表达。其中,以平均分子量为10000的壳寡糖对种子活力及幼苗的生长和抗病酶活性的影响最好,其发芽指数和活力指数分别比对照提高了32.64%、60.47%;苗高、可溶性蛋白含量、苯丙氨酸解氨酶、几丁质酶和β-1,3-葡聚糖酶活性分别比对照提高了20.98%、33.80%、43.17%、15.73%、26.41%。     

油菜内生阿氏芽孢杆菌鉴定及其对铬(Ⅲ)处理反应性分析

为探明耐铬(Ⅲ)油菜内生菌BNC-Q菌株对铬(Ⅲ)处理的生理生化反应性特点,以BNC-Q菌株为研究对象,进行了菌种鉴定以及铬(Ⅲ)处理反应性分析等试验.16S rDNA PCR分析结果表明,BNC-Q菌株为阿氏芽孢杆菌.铬(Ⅲ)胁迫培养试验结果表明,BNC-Q对铬(Ⅲ)耐受较强,可在5 mmol/L铬(Ⅲ)浓度条件下保持繁殖能力,可被不高于2 mmol/L的铬(Ⅲ)促进生长繁殖.蛋白质表达分析试验结果表明,经2 mmol/L铬(Ⅲ)处理后,BNC-Q可特异表达出一条约40 ku大小的蛋白质条带.抗氧化性分析试验结果表明,2 mmol/L铬(Ⅲ)处理对BNC-Q菌株清除DPPH自由基的能力基本无影响,但其对超氧阴离子自由基(O2-·)和羟基自由基(·OH)的清除率分别由63.7％,63.5％上升到91.1％,85.2％.综上所述,BNC-Q菌株为阿氏芽孢杆菌,对铬(Ⅲ)耐受性较强,可被铬(Ⅲ)诱导表达约40 ku的特异蛋白,铬(Ⅲ)诱导处理可显著提高其清除超氧阴离子自由基和羟基自由基的能力.研究结果可为重金属铬的生物修复研究提供一定的基础.     

低聚壳聚糖对小麦种子萌发以及幼苗生理生化特性的影响

以分子量为1500，2000，3000，4000，10000，20000的低聚壳聚糖为材料，研究了其对小麦种子萌发及幼苗生长的影响。实验表明：低聚壳聚糖能够有效地促进小麦种子萌发和幼苗生长，其促进作用的大小随低聚壳聚糖的分子量、浓度的不同而有较大的差异。以平均分子量为1500、浓度为0．2％的低聚壳聚糖的促进效果最好，可提高小麦种子的发芽势、发芽率和种子胚乳α-淀粉酶活性，使小麦幼苗叶片叶绿素含量和干物重分别提高26．2％和28．2％，叶片几丁质酶活性提高2～6倍。     

Ni-SOD模拟物的合成及其SOD活性测定

为研究Ni-SOD活性中心的结构与清除超氧阴离子自由基活性的关系,合成了3个以Ni2+为中心离子的SOD模拟物：Ni(bim)2(gly)2（1）,Ni(bim)3(L-asp)（2）和Ni(bim)3(L-glu)（3）,用元素分析、摩尔电导率、红外光谱和紫外-可见光谱对其进行了表征。此外,用氮蓝四唑(NBT)光还原法测定了模拟物1-3的SOD活性,其IC50值分别为0.25、0.25和0.38 μmol/L。结果表明：3个模拟物均具有相对较高的催化歧化超氧阴离子自由基O2-?的活性。这类SOD模拟物在植物抗逆增产方面有潜在的应用价值。     

Polyamines as Modulators of Soybean Productivity

Polyamines have been shown to be involved in several aspects of plant growth and development. In soybean, increase in number of pods per plant, 100 seed weight, seed, biological and oil yield was highest with spray of spermine and lowest (but significantly higher than control) with putrescine. The soybean seed and oil yield increased by about 12.46 and 20.94% respectively with application of 10⁻³ m spermine at 50% flowering stage. Another spray of polyamines at pod initiation stage had little effect on different parameters.     

我国大型种业企业要尽快加强企业法律顾问建设

当前对于我国广大种业企业而言,企业法律顾问还是一项崭新角色,企业法律顾问工作,也还是一项崭新的工作.大型种业企业要应对国内外竞争,寻求持续快速稳健发展,笔者认为必须紧跟企业内外形势要求,适时地尽快加强企业法律顾问建设工作.     

Talanoa as empathic apprenticeship

Talanoa has been defined as ‘talking about nothing in particular’, ‘chat’ or ‘gossip’. It is within the cultural milieu of talanoa that knowledge and emotions are shared and new knowledge is generated. Talanoa has recently been taken up by development researchers and others as a culturally appropriate research method in Pacific contexts. However, talanoa is often treated as synonymous with ‘informal open‐ended interviews’ and tends to gloss over the deep empathic understanding required in such exchanges. Highlighting the connection between talanoa and empathy is vital in ensuring that development practitioners and researchers are implicitly aware of the political dimensions, cultural appropriacy and socio‐ecological impact of their research methods. This connection is also critical in illuminating how talanoa as a method may decolonise research in the Pacific, inform the decolonisation of research in other cultural contexts, and contribute to ethical and empowering development policy and practice. We will argue for the merits of what we refer to here as ‘empathic apprenticeship’: an intentional, embodied, emotional, and intersubjective methodology and process between the researcher and the participant. An empathic apprenticeship has the potential to enhance shared understandings between all human beings and is essential if talanoa is intended as a decolonising research methodology.     

Analysis of Theory and Method about the Corrosion as well as the Broken Point of the Grounding Grid

The paper studies the theory about the corrosion as well as the broken point of the grounding grid in power plants and substations. By using sensitivity analysis, failure diagnosis equation is put up through rigorous theoretical analysis. Meanwhile the problem of morbid equation is solved by introducing lowest energy theory and technique of optimiation to diagnosis equation solution of grounding grid combined with definite constraint condition and linear or non-linear objective function, the fault diagnosis equation is discussed. The results of emulation calculation and analogous experiments verify the correctness,feasibility and practicality of the theory and method.     

黄秋葵作为禽用着色剂的品种比较试验

通过14个作为禽用着色剂的黄秋葵品系比较试验,分析其种子发芽率、产量（叶片、茎杆、种子）、营养成分（叶片、茎杆）。结果表明：14个品系的种子发芽率差异极显著,其中021和007-1发芽率最高,达到92.5%;叶片和茎杆平均干物质产量差异均亦极显著,004-2叶片干物质产量最高,达到4948kg/hm2,018茎秆干物质产量最高,达到7103.4kg/hm2;008的营养价值最高;种子产量007-1最高,公顷产量大于3000kg。综合评价,018品系作为禽用着色剂较适合推广种植。     

Selecting asparagus plants as sources of haploids

Summary The frequency with which haploid asparagus plants are found amongst multiple seedlings is shown to depend very largely upon which female plant is used as a source of seed. The implications of this observation particularly in relation to the accumulation of haploids and their utilisation in breeding F₁ hybrid asparagus are briefly discussed.     

菜薹型油菜栽培技术要点

1 品种选择 在当前生产中推广的几个"双低"油菜品种中,以浙双72最佳,其次可选择浙双6号、沪油15等.这几个品种菜薹品质好,油菜籽产量也高.     

三峡库区土地开发利用潜力与可持续发展 ——以重庆市万州区为例

利用建立的土地利用现状数据库，以三峡库区最大淹没区万州为研究对象，对库区土地开发利用潜力及生态安全性进行了分析和研究。揭示了库区土地资源利用中存在的主要危机是水土流失严重、生态环境脆弱，三峡工程淹没土地多、移民迁建占地比重大、人地矛盾加剧及粗放经营土地带来的安全隐患等问题。提出了保障基本农田的数量和质量、保障生态安全条件下的土地利用和建立库区土地资源安全保障体系是库区土地持续利用的战略选择。     

磨砺品牌做大做强迎接入世挑战

进入 21世纪以来,我国种业界出现了一些新情况:外贸协议的签定为中国种子公司带来空前的挑战和机遇;部分大公司逐步完成资本、技术积累,集团优势逐步形成;<种子法>的实施使县级种子公司面临全面重组的局面;由于县市级公司的重新排列组合,形成了种业界抢滩占地的春秋战国时期.     

Study on Hybridation and Aseptic Seeding as Well as Rapid Propogation of Demdrobium officinale and Dendrobium aduncum

[Objective]To study the system of aseptic seeding and rapid propogationtin of hybrid seeds of Demdrobium officinale and Dendrobium aduncum [Methods] Demdrobium officinale and Dendrobium aduncum were the objects of research,and their hybrid seeds were gained by artificially auxiliary hybridation. The seeds were induced to germinate in vitro,and study on the technology of aseptic seeding was finished. [Results]Successful hybridation of Demdrobium officinale and Dendrobium aduncum could be easily realized,and hybrid fruit-bearing rate could reach 80%; the suitable culture medium for seeds was: MS +1. 0 mg/L 6-BA +0. 1 mg/L NAA,the germination rate after 30 d of cultivation was 89. 7%; appropriate culture medium for proliferation of protocorm was: MS + 1. 5 mg /L 6-BA + 0. 1 mg /L NAA + 100 g /L banana + 1. 0 mg /L AC; appropriate culture medium for differentiation of protocorm was: MS + 1. 5 mg /L 6-BA + 0. 1 mg /L NAA + 200 g /L potato + 1. 0 g /L AC; the formula of culture medium for strenghening the seedlinge and nurturing the rooting was: 1 /2 MS + 0. 6 mg /L NAA +100 g /L banana + 1. 0 g /L AC,the plant grew robustly,the rooting percentage was 100%,and the survival rate of transplanting was higher than 95%. [Conclusions]This method ascertains the optimum culture media formula in the whole regeneration process and all phases from seed germination to acclimatization and transplantation,so fine solidation is laid for its germplasm innovation and industrialized seedling production.