荧光光谱法检测微藻中油脂

研究了尼罗红染色荧光光谱法检测微藻中油脂含量的方法.探讨了染色时间、尼罗红质量浓度、二甲基亚砜体积分数、细胞密度对藻液细胞发射光谱的影响,得到最佳测定条件为:染色时间6min,尼罗红质量浓度0.8 μg/mL,二甲基亚砜体积分数20%,细胞密度(0.248～0.448)×10<'9>个/mL.该研究为规模化筛选高含油量藻株及跟踪产油微藻油脂积累过程奠定了基础.     

蒙脱土填充环氧化天然橡胶/PVC热塑性弹性体的制备与性能研究

采用熔融插层法制备蒙脱土(MMT)/聚氯乙烯(PVC)插层产物,再将该产物与环氧化天然橡胶(ENR)在密炼机中进行动态硫化制备ENR/PVC/MMT共混型热塑性弹性体(TPE),研究了蒙脱土的填充量对共混物力学性能、热稳定性以及动态机械性能的影响。实验结果表明:随着蒙脱土填充量的增加,ENR/PVC/MMT共混型热塑性弹性体的拉伸强度、撕裂强度和邵氏硬度增大,断裂伸长率略有下降;蒙脱土会促进TPV中PVC的降解,使得复合材料的热稳定性降低,动态热机械分析测得的复合材料的tanδ曲线峰峰强降低,峰宽变宽。     

Identification,Functional Study,and Promoter Analysis of HbMFT1, a Homolog of MFT from Rubber Tree (Hevea brasiliensis)

A homolog of MOTHER OF FT AND TFL1 (MFT) was isolated from Heveabrasiliensis and its biological function was investigated. Protein multiple sequence alignment and phylogenetic analysis revealed that HbMFT1 conserved critical amino acid residues to distinguish MFT, FLOWERING LOCUS T (FT) and TERMINAL FLOWER1 (TFL1)-like proteins and showed a closer genetic relationship to the MFT-like group. The accumulation of HbMFT1 was generally detected in various tissues except pericarps, with the highest expression in embryos and relatively higher expression in roots and stems of seedlings, flowering inflorescences, and male and female flowers. HbMFT1 putative promoter analysis showed that tissue-specific, environmental change responsive and hormone-signaling responsive elements were generally present. HbMFT1 was strongly induced under a short-day condition at 28 °C, with the highest expression after the onset of a day. Overexpression of HbMFT1 inhibited seed germination, seedling growth, and flowering in transgenic Arabidopsis. The qRT-PCR further confirmed that APETALA1 (AP1) and FRUITFULL (FUL) were drastically down-regulated in 35S::HbMFT1 plants. A histochemical β-glucuronidase (GUS) assay showed that HbMFT1::GUS activity was mainly detected in stamens and mature seeds coinciding with its original expression and notably induced in rosette leaves and seedlings of transgenic Arabidopsis by exogenous abscisic acid (ABA) due to the presence of ABA cis-elements in HbMFT1 promoter. These results suggested that HbMFT1 was mainly involved in maintenance of seed maturation and stamen development, but negatively controlled germination, growth and development of seedlings and flowering. In addition, the HbMFT1 promoter can be utilized in controlling transgene expression in stamens and seeds of rubber tree or other plant species.     

气相色谱法和蒸馏-酒精计法测定木薯发酵液中酒精含量的比较

分别采用气相色谱法和蒸馏-酒精计法测定了不同发酵时间段木薯发酵液中的酒精含量。研究结果表明,气相色谱法的测定结果更加准确、稳定,而蒸馏-酒精计法的精确度较低、误差较大。     

余甘子核仁油微胶囊的制备及其稳定性分析

以阿拉伯胶和麦芽糊精为壁材,对喷雾干燥法制备余甘子核仁油微胶囊的工艺进行研究。通过单因素试验和响应面优化试验考察乳化剂添加量、阿拉伯胶与麦芽糊精质量比、芯壁比及固形物添加量对余甘子核仁油微胶囊包埋率的影响,得到最优微胶囊制备条件为乳化剂添加量1%、阿拉伯胶与麦芽糊精质量比1∶3.4、芯壁比2∶3、固形物添加量14.2%,该工艺条件下得到的余甘子核仁油微胶囊的包埋率达到（90.74±0.51）%,包埋效果好,颗粒形态完整。采用油脂氧化稳定性测定仪（Rancimat法）测定该样品的氧化诱导时间,并对微胶囊在25?℃条件下的货架期进行预测发现,微胶囊的货架期为716?d,未包埋的余甘子核仁油货架期为128?d,由此可见该微胶囊具有良好的贮藏稳定性。     

1-甲基环丙烯处理对樱桃番茄果实低温贮藏品质的影响

为了探讨低温贮藏条件下1-甲基环丙烯(1-methylcyclopropene,1-MCP)处理对樱桃番茄果实采后品质的影响,该研究以'粉娇'樱桃番茄为试材,测定了经1-MCP(0.14μL/L)处理的樱桃番茄在低温[(8±1)℃]贮藏期间果实腐烂率、呼吸强度、果实硬度、可溶性固形物、维生素C、有机酸和类胡萝卜素含量的...     

Evaluation of different methods of protein extraction and identification of differentially expressed proteins upon ethylene-induced early-ripening in banana peels

BACKGROUND: Banana peels (Musa spp.) are a good example of a plant tissue where protein extraction is challenging due to the abundance of interfering metabolites. Sample preparation is a critical step in proteomic research and is critical for good results. RESULTS: We sought to evaluate three methods of protein extraction: trichloroacetic acid (TCA)‐acetone precipitation, phenol extraction, and TCA precipitation. We found that a modified phenol extraction protocol was the most optimal method. SDS‐PAGE and two‐dimensional gel electrophoresis (2‐DE) demonstrated good protein separation and distinct spots of high quality protein. Approximately 300 and 550 protein spots were detected on 2‐DE gels at pH values of 3–10 and 4–7, respectively. Several spots were excised from the 2‐DE gels and identified by mass spectrometry. CONCLUSIONS: The protein spots identified were found to be involved in glycolysis, the tricarboxylic acid cycle, and the biosynthesis of ethylene. Several of the identified proteins may play important roles in banana ripening. Copyright © 2012 Society of Chemical Industry     

几种杀虫剂对瓜菜上斜纹夜蛾和棉铃虫的毒力测定

[目的]筛选对瓜菜上斜纹夜蛾和棉铃虫防治高效且对有益昆虫低毒的杀虫剂,指导菜园科学合理用药。[方法]室内测定5种杀虫剂对斜纹夜蛾、棉铃虫、中华蜜蜂和椰心叶甲啮小蜂的室内毒力。[结果]高效氯氟氰菊酯对斜纹夜蛾3龄幼虫毒力最高,甲维盐对棉铃虫3龄幼虫毒力最高,毒死蜱对中华蜜蜂工蜂的毒力最高,LC50值分别为10.593 3、3.525 2、1.486 5 mg/L。高效氯氟氰菊酯、甲维盐和氯虫苯甲酰胺对斜纹夜蛾和棉铃虫毒力相当,但高效氯氟氰菊酯和甲维盐对中华蜜蜂和椰心叶甲啮小蜂毒力较低。[结论]推荐使用高效氯氰菊酯和甲维盐治瓜菜上的斜纹夜蛾和棉铃虫。     

蛋白质含量对天然橡胶性能的影响简

研究蛋白质含量为0.5%~2.7%的天然橡胶(NR)生胶的理化性能、硫化胶的物理性能、耐热老化性能、永久变形性能和压缩生热。结果表明:不同蛋白质含量的NR生胶的理化性能基本相同;随着蛋白质含量降低,NR硫化胶的定伸应力、拉伸强度和撕裂强度呈先升后降的趋势,压缩永久变形减小,压缩生热降低,蛋白质含量低于1%时耐热老化性能明显降低。蛋白质含量在1.0%左右NR硫化胶的综合性能最好。     

沉香油研究进展

沉香油是从沉香中提取出的低极性或挥发性的油状物质,是沉香中致香成分的精华,因稀有珍贵,其价格一直居高不下。综述介绍了沉香油的提取方法、化学成分、药理活性、用途和市场情况等方面的内容。