新法构建25-羟基油菜甾体的侧链

油菜甾体例如油菜甾醇内酯(1a)和24-表油菜甾醇内酯(2a)是一族新型的甾体植物生长激素(植物生长调节剂).它们具有提高植物生长调节和应变的活性并具有农作物增产效果,已愈益受到国际上的广泛重视[1].     

基于在线富集与原位衍生技术的植物组织中内源性油菜素甾醇的超高效液相色谱-串联质谱分析方法

油菜素甾醇是一类重要的植物激素,对植物的生长发育过程起显著调节作用。已报道的油菜素甾醇分析方法存在样品前处理过程复杂和灵敏度低等问题。本研究采用C18 PEEK管填充柱为富集柱,以4-N,N-二甲氨基苯硼酸为衍生试剂,搭建了基于双泵-双六通阀的在线管内固相微萃取-超高效液相色谱-串联质谱（UPLC-MS/MS）联用系统,对油菜素甾醇进行在线富集和原位衍生,实现植物组织中内源性油菜素甾醇的自动化分析。该系统程序化地控制了油菜素甾醇的进样、萃取、衍生、分离和检测过程,有效简化前处理过程,节省人力;在线富集步骤实现了样品溶液大体积进样,提高样品利用率;原位衍生改善了油菜素甾醇电喷雾的离子化效率,使油菜素甾醇的电喷雾质谱检出限降低至pg/mL。该系统可在300 mg鲜重植物组织中检测到内源性油菜素甾醇,已成功用于水稻、油菜中多种油菜素甾醇的定量分析。     

固相萃取-色谱/质谱技术在油菜素内酯分析中的研究进展

油菜素内酯(brassinosteroids, BRs)是一类重要的植物激素,参与调节植物的各个生理过程. 确定BRs在不同植物组织中的含量有利于进一步了解其作用机制. 由于此类激素内源含量极低、植物基质复杂等原因,BRs的定量分析面临较大挑战. 固相萃取及其衍生方法(固相微萃取、磁性固相萃取等)以及色谱-质谱技术的发展,能显著提高BRs分析过程中的样品前处理效率、减少植物样品需求量、增强定性定量的准确度. 综述了近10年来固相萃取-色谱/质谱技术在BRs检测中的研究进展,期望能为此类植物激素的灵敏、高效测定提供方法指导.     

3-苯甲酰基-4-羟基香豆素衍生物的合成、晶体结构及其除草活性研究

利用活性叠加的原理,设计合成了带有三酮类结构的3-苯甲酰基-4-羟基香豆素衍生物.用1H NMR,13C NMR,HRMS和X-ray单晶衍射对其进行了结构鉴定.用平皿小杯法和盆栽法评价了其对双子叶植物油菜和单子叶植物稗草的抑制活性.结果显示,目标化合物表现出与香豆素相似的活性,只对油菜有很好的抑制活性,苯甲酰基的接入能一定程度上提高4-羟基香豆素对油菜的活性.部分化合物对油菜表现出良好的活性,其中,3-(2-硝基-4-甲磺酰基苯甲酰基)-4-羟基香豆素(21)对油菜根长的抑制活性好于甲基磺草酮,10 μg/mE时,抑制率能达到87.6％,但盆栽活性比甲基磺草酮差.目标化合物虽然具有与三酮除草剂类似的结构,但并不表现出明显的白化作用,具有与三酮类除草剂不同的作用模式.化合物21对双子叶植物油菜表现出很好的选择性,可以作为开发新型选择性除草剂的先导结构,继续结构优化.     

甾体植物生长促进剂的研究 VIII: 3α-羟基-7-氧-6-酮-B-高-5α-胆烷酸甲酯的区域选择性合成

油菜甾醇是以油菜花粉分离到的一种促进植物生长甾体, 能促进细胞生长和分裂,与已知植物生长的元素相比, 它具有广谱生物活性, 因此他可能在农业上有实际应用的价值.本文报道了3α-羟基-7-氧-6-酮-B-高-5α-胆烷酸甲酯的区域选择性合成.     

甾体植物生长促进剂的研究 VIII: 3α-羟基-7-氧-6-酮-B-高-5α-胆烷酸甲酯的区域选择性合成

油菜甾醇是以油菜花粉分离到的一种促进植物生长甾体, 能促进细胞生长和分裂,与已知植物生长的元素相比, 它具有广谱生物活性, 因此他可能在农业上有实际应用的价值.本文报道了3α-羟基-7-氧-6-酮-B-高-5α-胆烷酸甲酯的区域选择性合成.     

钕在油菜中的分布、运输与细胞定位

用透射电镜对经济培养油菜苗的观察表明,钕不能进入细胞质,而是细胞壁细胞或沉积在细胞间隙,钕从根系进入植物后多数在根尖积累,少量经质外体转运到茎和叶,其中叶尖最少,与土培试验油菜各部位组织中钕含量的分析结果相吻合。钕对植物的生理效应可能主要通过作用于根系质膜而表现出来。     

高效液相色谱切换波长法测定多组分体系

1引言目前植物激素常采用反相高效液相色谱法检测,但植物中激素等多种组分同时存在,单一波长不能使每个组分都在最佳检测波长下检测。本实验采用切换波长法对植物样品进行多组分检测分析,提高了检测灵敏度。采用反相高效液相色谱法(HPLC)同时测定油菜中的内源激素赤霉素(GA3)、     

高等植物根原生质体的分离和培养

本文由12种植物,其中包括8种豆科植物(绿豆、黑绿豆、大豆、豌豆、木豆、蚕豆、苜蓿和胡卢巴)和4种十字花科植物(油菜、本油菜、甘兰和白芥)的萌发种子的幼根分离得到了根原生质体.根原生质体在培养中表现出活跃的分裂能力.除了在木豆和蚕豆中仅观察到细胞分裂外,其余10种植物的根原生质体均形成了愈伤组织。其中苜蓿根原生质体通过形成胚状体再生了植株,而油菜和甘兰的根原生质体通过愈伤组织诱导成芽也再生了植株,由此证明了根原生质体的全能性.这为那些在分离或培养原生质体方面仍存在困难的植物种提供了另一可供选择的系统.本文还讨论了这一系统的优点以及存在的问题。     

甾体植物生长促进剂的研究——Ⅷ.3α-羟基-7-氧-6-酮-B-高-5α-胆烷酸甲酯的区域选择性合成

油菜甾醇(Brassinolide,1)是以油菜(Brassica napus)花粉分离到的一种促进植物生长的甾体,能促进细胞生长和分裂,与已知植物生长激素相比,它具有广谱的生物活性。因此它可能在农业上有实际应用的价值。最近发现以宽叶香蒲(Typla latifolia L)花粉中分离到的香蒲甾醇(2)和2α,3α-双羟     

钙基负载型固体碱催化酯交换反应活性评价

动植物油脂与醇通过酯交换反应制备生物柴油,目前,工业上一般采用NaOH、KOH、NaOCH,等均相催化剂。均相催化剂的缺点是产品后处理复杂,产生大量含碱含油工业废水。而非均相固体碱催化酯交换反应,产品与催化剂分离容易,产品不需要水洗,避免了大量废液的排放。采用非均相固体碱制备生物柴油的文献报道较多,但固体碱的碱中心数、碱中心强度对酯交换反应影响的报道较少。本研究制备了钙基负载型固体碱催化剂,重点研究钙基负载型固体碱的制备工艺条件对碱强度、碱量分布的影响,考察碱强度、碱量分布对催化菜籽油与甲醇的酯交换反应制备生物柴油转化率的影响。     

Determination of acetolactate synthase activity and protein content of oilseed rape (Brassica napus L.) leaves using visible/near-infrared spectroscopy

A new acetolactate synthase (ALS)-inhibiting herbicide, propyl 4-(2-(4,6-dimethoxypyrimidin-2-yloxy)benzylamino)benzoate (ZJ0273), was applied to oilseed rape (Brassica napus L.) leaves in different leaf positions. Visible/near-infrared (Vis/NIR) spectroscopy was investigated for fast and non-destructive determination of ALS activity and protein content in rapeseed leaves. Partial least squares (PLS) analysis was the calibration method with comparison of different spectral preprocessing by Savitzky-Golay (SG) smoothing, standard normal variate (SNV), first and second derivative. The best PLS models were obtained by first-derivative spectra for ALS, whereas original spectra for soluble, non-soluble and total protein contents. Simultaneously, certain latent variables (LVs) were used as the inputs of back-propagation neural network (BPNN) and least squares-support vector machine (LS-SVM) models. All LS-SVM models outperformed PLS models and BPNN models. The correlation coefficient (r), root mean square error of prediction (RMSEP) and bias in validation set by LS-SVM were 0.998, 0.715 and 0.079 for ALS, 0.999, 33.084 and 1.178 for soluble protein, 0.997, 42.773 and 6.244 for non-soluble protein, 0.999, 59.562 and 7.437 for total protein, respectively. The results indicated that Vis/NIR spectroscopy combined with LS-SVM could be successfully applied for the determination of ALS activity and protein content of rapeseed leaves. The results would be helpful for further on field analysis of using Vis/NIR spectroscopy to monitor the growing status and physiological properties of oilseed rape.     

Pressurised fluid extraction (PFE) as an alternative general method for the determination of pesticide residues in rape seed

A pressurised fluid extraction (PFE) multi-method has been developed for the determination of pesticide residues in rape seed. The method was validated for 25 different pesticides and metabolites. The reliability and efficiency of PFE for extracting pesticide residues from rape seed was investigated. The traditional extraction solvent, hexane saturated with acetonitrile, was used at elevated temperature and pressure. With increased temperature, the extraction kinetics were improved but at the same time more co-extractives were obtained in the form of lipids. When 1 g of rape seed was extracted at temperatures from 60 degrees C to 150 degrees C, the lipid content extracted was found to be as high as 17-26%. An additional clean-up step was therefore required and lipid co-extractives were effectively removed by gel permeation chromatography. The interpretation of the chromatograms and the quantification of the results were satisfactorily improved by the removal of interfering lipids. The developed method was used to extract vinclozolin and iprodione from incurred samples, resulting in a concentration in accordance with the results using conventional liquid-liquid extraction (LLE) between hexane and acetonitrile and also supercritical fluid extraction (SFE) using carbon dioxide. The results of the present study suggest that PEE is a good alternative extraction technique for the determination of pesticide residues in oil seed. Despite the necessity for a lipid-removal clean-up step, the PFE technique facilitated the extraction process by faster extractions and the possibility of automated analysis.     

应用校正变换矩阵法识别掺伪食用油

根据食用油中脂肪酸、甾醇以及生育酚含量,应用校正转换矩阵法对花生油掺伪进行了定量检测。用所建立的校正模型对棕榈油、菜籽油和棉籽油掺入到花生油所得到的２７个二元和６个四元人工合成样品进行了验证,结果令人满意。对从市场上购得的５种花生油进行了测定,其中一种是由菜籽油假冒的花生油,另一种为掺入花生精油的棕榈油。     

高硒情况下维生素E对老龄大鼠血清中抗氧化作用的影响

研究了高Se或高维生素E下，老龄大鼠体内抗氧化活性的变化以及高Se下维生素E对其体内抗氧化水平的影响。将十二月龄Wistar大鼠32只随机分成4组：（1）正常饲料组；（2）高Se饲料组；（3）高维生素E饲料组；（4）高Se高维生素E饲料组。饲至十周末，处死大鼠，按试剂盒要求取其血液制成血清测GSH－Px,SOD活性，MDA含量。结果表明，高Se或高维生素E下饲养下的大鼠与对照组比较，血清中GSH－Px活性升高（P＜0．05）。SOD活性未见改变，MDA含量分别减少50％和56％，有显著差异（P＜0．01）；维生素E与高Se合用与高Se组比较能进一步同GSH－Px,SOD活性（P＜0．01）。结论：高Se会升高老龄大鼠的抗氧化活性，而与维生素E合用更加升高老龄大鼠血液中抗氧化活性。     

Determination of Ascorbic Acid,Total Ascorbic Acid,and Dehydroascorbic Acid in Bee Pollen Using Hydrophilic Interaction Liquid Chromatography-Ultraviolet Detection

Ascorbic acid (AA) is one of the essential nutrients in bee pollen, however, it is unstable and likely to be oxidized. Generally, the oxidation form (dehydroascorbic acid (DHA)) is considered to have equivalent biological activity as the reduction form. Thus, determination of the total content of AA and DHA would be more accurate for the nutritional analysis of bee pollen. Here we present a simple, sensitive, and reliable method for the determination of AA, total ascorbic acids (TAA), and DHA in rape (Brassica campestris), lotus (Nelumbo nucifera), and camellia (Camellia japonica) bee pollen, which is based on ultrasonic extraction in metaphosphoric acid solution, and analysis using hydrophilic interaction liquid chromatography (HILIC)-ultraviolet detection. Analytical performance of the method was evaluated and validated, then the proposed method was successfully applied in twenty-one bee pollen samples. Results indicated that contents of AA were in the range of 17.54 to 94.01 µg/g, 66.01 to 111.66 µg/g, and 90.04 to 313.02 µg/g for rape, lotus, and camellia bee pollen, respectively. In addition, percentages of DHA in TAA showed good intra-species consistency, with values of 13.7%, 16.5%, and 7.6% in rape, lotus, and camellia bee pollen, respectively. This is the first report on the discriminative determination between AA and DHA in bee pollen matrices. The proposed method would be valuable for the nutritional analysis of bee pollen.     

Preparation and Tribological Behaviors of Lubricants—Oil Based on Modified Microbial Oil with Nano-Schiff Base Copper Complex

A W/O microemulsion reactor was used to prepare four kinds of modified lubricants: (i) modified lubricant 1, modified epoxidized microbial oil + rape oil in volume ratio of 1:1; (ii) modified lubricant 2, modified esterified microbial oil + rape oil in volume ratio of 1:3; (iii) modified lubricant 3, modified epoxidized rape oil; and (iv) modified lubricant 4, modified PAO. The individual modified lubricants were further modified with 0%, 0.5%, 1%, and 2% content of nano-Schiff base copper complex (nano-SBCC). A microtribometer was used to evaluate the friction coefficient between ball/flat point contacts immersed in the modified lubricants and operated in reciprocating and linear sliding mode. A comparison of the values of the friction coefficient with the lubricants further modified with nano-SBCC with those of their individual 0% nano-SBCC counterparts indicated significant decrease: (i) almost 19.18% was obtainable for the modified lubricant 1 with 2% of nano-Schiff base copper complex, (ii) almost 16.5% was obtainable for the modified lubricant 2 with 0.5% of nano-Schiff base copper complex; (iii) almost 7.42% was obtainable for the modified lubricant 3 with 1% of nano-SBCC; and (iv) almost 7.01% was obtainable for the modified lubricant 4 with 0.5% of nano-SBCC. These suggested that the addition of nano-Schiff base copper complex can efficiently decrease the friction coefficient of epoxidized or esterified microbial oil. Analyses of two-dimensional images, average profiles (across the mid-section y = 0 of the reciprocating sliding path), and three-dimensional topographies by confocal white light microscope for the worn surfaces of flats immersed in modified lubricant 1 and modified lubricant 2 suggested better wear-resistance of the modified lubricant 2 than that of the modified lubricant 1. The ability of wear resistance for the modified lubricant became better with the increasing content of nano-Schiff base copper complex from 0% to 2%. The study revealed the modification of epoxidized microbial oil + rape oil (1:1 volume ratio) and esterified microbial oil + rape oil (1:3 volume ratio) with Cu(II) chelate of bis(salicylaldehyde)ethylenediamine, reducing the magnitude of friction and wear because of their respective wear self-repairing ability. Such self-repairing ability furnishes the suitability of epoxidized microbial oil or esterified microbial oil to be effectively modified by nano-Schiff base copper complex and to substitute ordinary base oil as a mixture with rape oil.     

Ethanol-induced changes in glycolipids of Saccharomyces cerevisiae

Total glycolipid content of Saccharomyces cerevisiae cells increased in ethanol-treated yeast cells. Sialic acid and hexosamine contents of glycolipids from ethanol-treated cells decreased, whereas those of hexoses increased. Increased sialidase activity in the presence of ethanol may be responsible for the decrease in sialic acid content of glycolipids. The saccharide moieties of glycolipids of S. cerevisiae consisted of fucose, mannose, galactose, and glucose. Ethanol treatment of yeast cells caused an increase in glucose and a decrease in galactose content of glycolipids. The changes in glucose content can be related to changes in β-glucosidase activity under alcohol stress. The content of cerebrosides, sulfatides, and monoglucosyldiglycerides was enhanced following ethanol treatment. An increase in cerebroside as well as in sulfatide content during alcohol stress might play an important role in stabilizing the membrane both physically and structurally. Such variations in glycolipid content and composition of S. cerevisiae cells may represent an adaptive response to ethanol stress.     

油菜蜂花粉黄酮含量的HPLC测定

以95％乙醇为溶剂,采用索氏提取器提取青海产油菜蜂花粉中的黄酮类化合物,将黄酮提取物中的黄酮甙水解为黄酮甙元后,利用HPLC法测定其中槲皮素、山萘酚、异鼠李素含量。结果表明,青海油菜蜂花粉中槲皮素、山萘酚、异鼠李素的平均含量分别为0．928％、0．295％、0．0834％,换算成总黄酮含量为3．28％。