山药叶片总RNA提取方法的比较

[目的]提取高质量的山药叶片总RNA。[方法]以山药叶片为材料,采用异硫氰酸胍法、改良CTAB法提取山药叶片总RNA并进行比较分析,利用琼脂糖凝胶电泳分析所提RNA的完整性,并用紫外分光光度计分析RNA的纯度。[结果]改良CTAB法提取的总RNA的28S、18SrRNA条带清晰、整齐,测得A260/A280为1.72.0。[结论]改良的CTAB法适合山药叶片总RNA提取。     

基于金纳米团簇的比率型pH荧光探针制备及表征

在合成牛血清白蛋白(BSA)修饰的金纳米团簇(金簇)的基础上,将荧光素异硫氰酸酯(FITC)与金簇偶联,构建一种新型比率型p H荧光探针。当体系p H值在4.0~10.0之间变化时,FITC的荧光强度逐渐增加,而金簇的荧光强度基本保持不变。在p H为5.5~8.0之间,该探针对于p H具有良好的线性关系,线性方程为Y=1.72X-8.8,相对标准偏差为0.994,同时该探针在p H为6.0~9.0之间还具有良好的可逆性。此外,将此p H荧光探针与PK15细胞共培养,通过MTT实验证明该比率型p H荧光探针对细胞几乎没有毒性。     

番木瓜种子中异硫氰酸苄酯（BITC）的抑癌试验

利用MTT法检测番木瓜种子中的异硫氰酸苄酯(BITC)在体外对肝癌细胞等6种常见癌细胞的生长抑制率。结果表明,番木瓜种子提取物中BITC的浓度达到5μmol.L-1(相当于0.745mg.L-1)时,对人肝癌HepG2细胞、人肺癌A549细胞、人乳腺癌MCF-7细胞、人大肠癌HCT-8细胞、人宫颈癌HeLa细胞、人前列腺癌DU-145细胞的生长抑制率均达到70%以上,其中,人肝癌细胞HepG2最敏感,cBITC=2.5μmol.L-1时抑制率可达87%,在cBITC=10μmol.L-1和5.0μmol.L-1时,人大肠癌HCT-8细胞的生长抑制率几乎相同。因此,BITC具有良好的抑癌效果。     

山药组织总RNA提取方法的比较与分析

采用异硫氰酸胍一巯基乙醇联合变性法、Trizol法和CTAB—LiCl法等3种方法,分别对山药叶片和块茎进行总RNA提取效果进行了比较。结果表明,Trizol法难以提取RNA,异硫氰酸胍-巯基乙醇联合变性法提取RNA效果不理想,存在DNA污染,这2种方法不适合于富含多糖类物质的山药组织总RNA的提取;CTAB-LiCl法提取叶片和块茎组织总RNA质量高、完整性好、成功率高,可作为山药类植物总RNA提取的首选方法。     

烯丙氧基不对称硫逐磷酸酯的合成及其重排效应研究

采用相转移双催化技术,以79%~95%的收率合成了9种O-烯丙基-O-芳基-O-甲基不对称硫逐磷酸酯( Ⅲ );并通过 Ⅲ 的重排反应合成了烯丙硫基不对称硫赶磷酸酯,重排前后化合物的结构均得到了元素分析、IR、1H NMR和31P NMR的证实;对这些化合物杀虫活性的重排效应现象作了初步研究。     

Extraction of allyl isothiocyanate from horseradish (Armoracia rusticana) and its fumigant insecticidal activity on four stored‐product pests of paddy

BACKGROUND: Isothiocyanates (ITCs) extracted from Armoracia rusticana Gaertn., May & Scherb. have been shown previously to have insecticidal activity. Allyl isothiocyanate (AITC), a major component of ITCs with high volatility, was therefore extracted using different methods and tested as a fumigant against four major pest species of stored products, maize weevil Sitophilus zeamais (Motsch.), lesser grain borer Rhizopertha dominica (F.), Tribolium ferrugineum (F.) and book louse Liposcelis entomophila (Enderlein). RESULTS: Whereas there was no significant difference between hydrodistillation and supercritical carbon dioxide fluid extraction in extraction rate for AITC from A. rusticana, both methods resulted in higher extraction efficiency than water extraction. AITC fumigation showed strong toxicity to the four species of stored‐product pests. Adult mortality of 100% of all four pest species, recorded after 72 h exposure to AITC fumes at an atmospheric concentration of 3 µg mL^?1, showed no significant difference from that of insects exposed to phosphine at 5 µg mL^?1, the recommended dose for phosphine. CONCLUSIONS: The results suggest good insecticidal efficacy of AITC against the four stored‐product pests, with non‐gaseous residuals on stored products. AITC obtained from A. rusticana may be an alternative to phosphine and methyl bromide against the four pest species. Copyright © 2009 Society of Chemical Industry     

Biofumigation: An alternative strategy for the control of plant parasitic nematodes

Plant-parasitic nematodes wreak havoc on the yield and quality of crops worldwide. Damage from these pests is estimated to exceed US$100 billion annually but is likely higher due to misdiagnosis. Nematode damage may be catastrophic, but historically the solution has been damaging as well. Use of the synthetic nematicide methyl bromide(MBr) poses risks to the environment and to human health. Biofumigation, the use of plant material and naturally produced compounds to control pests, is an increasingly feasible method of pest management. The process acts through the growth or incorporation of plant material into the soil, that, over the course of its degradation, releases glucosinolates that break down into nematotoxic isothiocyanates. These secondary plant metabolites exist naturally in commonly grown plants, most of which belong to the Brassicaceae family. Research endeavors have increasingly explored the potential of biofumigation. The reaction of target pests, the selection of biofumigant, and ideal environments for efficacy continue to be evaluated. This review seeks to provide a cost and benefit assessment of the status of biofumigation for the control of plant-parasitic nematodes as an alternative to conventional methyl bromide usage.     

甘蔗茎RNA提取方法的比较

以甘蔗茎为材料,分别用异硫氰酸胍法与Trizol提取法,比较从蔗汁、蔗渣和汁渣混合物匀浆中提取甘蔗茎总RNA的效果。结果表明,从蔗汁和汁渣混合物匀浆中提取到28S rRNA、18S rRNA和5S rRNA,而蔗渣中仅提取到5S RNA;蔗汁中提取的mRNA,其转录水平可代表甘蔗茎mRNA的转录水平;异硫氰酸胍法提取的蔗汁总RNA纯度和产量均优于Trizol提取法的。     

聚松香丙烯醇酯及其氧化物的合成及表征(Ⅱ)——大孔网状聚松香丙烯醇酯氧化物的合成研究

以歧化松香胺席夫碱铜催化剂,H2O2(30%)氧化聚松香丙烯醇酯(PRAAE),得到聚松香丙烯醇酯氧化物。对聚合物进行了红外、紫外、软化点和热失重分析,BET法测定聚松香丙烯醇酯氧化物的微孔大部分分布在5nm以上;对聚松香丙烯醇酯氧化物相对分子质量进行了分析,其量在25266以上。结果表明所合成的聚松香丙烯醇酯氧化物为大孔聚合物。