川桂叶中黄酮类化合物的提取与测定

采用加热回流法提取川桂叶中的黄酮类化合物,建立了川桂叶中总黄酮含量测定的光谱分析方法。结果表明：以芦丁为标准品,用NaNO2-Al（NO3）3-NaOH显色法可测定川桂叶中总黄酮的含量,该方法的精密度和准确度均较高,相对标准偏差为0.63%,方法的回收率为97.18%—102.20%。通过正交试验优化,得到提取川桂叶中黄酮类化合物的最佳工艺条件是：用体积分数为70%的乙醇作溶剂,在固液比1∶20（g/mL）、提取温度80℃的条件下提取1.5h,连续提取2次。测得川桂叶中总黄酮含量为22.53mg·g^-1。     

火焰原子吸收法测定夏枯草、桑叶、野菊花中十种微量元素

湿法消化样品 ,火焰原子吸收法测定三种草药中的 Mg、Ca、Zn、Mn、Co、Ni、Pb、Cd、Fe、Cu等 10种微量元素。回收率分别为 97.7%— 10 1.5 % ;96 .0 %— 10 5 .1% ;97.1%— 10 3.6 % ,相对标准偏差为 1.6 %—4 .5 % ;1.7%— 4 .7% ;1.7%— 4 .6 %。结果表明 ,三种草药均含有丰富的微量元素如 Mg、Ca、Zn、Mn、Fe、Cu等 ;为原料的开发和应用提供有效数据。     

香樟受酸胁迫影响的高光谱诊断模型

高光谱作为快速、无损诊断技术,在植物胁迫监测中发挥了重要作用。但是因为硫和氮的施肥作用,植物对酸雨的响应表现出比其他胁迫更加复杂的模式。基于高光谱技术对香樟受四个酸雨梯度(pH 5.6,pH 4.5,pH 3.0,pH 2.0)影响的叶片光谱进行了419天的监测,以探讨不同酸雨梯度对香樟影响的时间拐点。首先对16期原始光谱数据进行预处理,剔除异常值;然后基于光谱差值(对照组pH 5.6与其他酸雨梯度处理下的叶片光谱差)随着喷酸时间的变化,寻找典型波段;在此基础上构建了香樟在酸雨处理下的光谱响应模型。主要结论如下：反映香樟受酸雨影响的典型波段主要集中在470~520和565~700 nm,在此基础上构建了蓝边差值指数和黄边差值指数。低(pH 4.5)、中(pH 3.0)浓度的酸雨对香樟生长均呈现出先促进后抑制的作用,时间拐点分别发生在喷酸的第100天和50天左右;高浓度酸雨(pH 2.0)从喷酸初期就表现出抑制香樟生长,且随着喷酸时间的增加抑制作用增强。研究表明,长时间序列的高光谱信息可以指示不同强度的酸雨对植物的促进和胁迫作用,以及由促进到胁迫的时间拐点;该研究也为基于卫星遥感监测区域尺度植物受酸胁迫提供了借鉴,同时为相关部门制定酸雨政策提供了科学依据。     

Industrial application of green chromatography--I. Separation and analysis of niacinamide in skincare creams using pure water as the mobile phase

In this work, chromatographic separation of niacin and niacinamide using pure water as the sole component in the mobile phase has been investigated. The separation and analysis of niacinamide have been optimized using three columns at different temperatures and various flow rates. Our results clearly demonstrate that separation and analysis of niacinamide from skincare products can be achieved using pure water as the eluent at 60 °C on a Waters XTerra MS C18 column, a Waters XBridge C18 column, or at 80 °C on a Hamilton PRP-1 column. The separation efficiency, quantification quality, and analysis time of this new method are at least comparable with those of the traditional HPLC methods. Compared with traditional HPLC, the major advantage of this newly developed green chromatography technique is the elimination of organic solvents required in the HPLC mobile phase. In addition, the pure water chromatography separations described in this work can be directly applied in industrial plant settings without further modification of the existing HPLC equipment.     

大孔吸附树脂纯化杜仲叶加工剩余物中的京尼平苷酸

以杜仲叶加工剩余物为原料,研究(比较)了S-8、AB-8、D101和X-5 4种大孔吸附树脂对杜仲中的降血压活性成分京尼平苷酸(GPA)的吸附及脱附性能。以S-8型树脂吸附-水脱附工艺纯化GPA的优化工艺为:脱附剂用量300mL、脱附流速3mL/min、上柱液pH值1.0,脱附过程的最大影响因素为脱附剂流速,GPA的脱附率达89.64%,GPA含量由7.23%提高到45.18%。     

ICP-AES法测定蒙古扁桃叶片中元素含量

用HNO3-HClO4消解体系对蒙古扁桃叶片进行消解制样,利用电感耦合等离子体发射光谱法(ICP-AES)同时测定了蒙古扁桃叶片中Ca,Mg,Fe,Mn,Cu,Zn,Al,Sr,Sn和Pb等十种元素的含量,加标回收率为93%～110%,RSD为0.33%～2.94%。结果表明,该方法快速、简便、数据准确可靠,结果令人满意,为其综合开发利用提供科学依据。     

Isolation and determination of ginsenosides in American ginseng leaves and root extracts by LC-MS

Ginseng saponins (ginsenosides) were extracted from the root and leaves of locally cultivated American ginseng (Panax quinquefolium L.). For the isolation of compounds from plant samples three different extraction methods were utilized: accelerated solvent extraction, the ultrasound-assisted solvent extraction and mechanical shaking assisted solvent extraction. The separation of compounds was achieved with a water–acetonitrile gradient system using a C18 reversed-phase column. Target compounds were identified in MS² and MS³ experiments. The relative distribution of these ginsenosides in each root and leaf extract was established. The limit of detection of the method was less than 30 ng/ml. Recovery of ginseng saponins in spiked samples exceeded 80%, while the relative standard deviation ranged from 7.1 to 9.1%. The total concentrations of ginsenosides were 41 and 13 mg/g in root and leaves.     

同步辐射XRF法分析温室油菜中微量元素的分布

蔬菜是补充人体微量元素的重要途径,但是蔬菜不同部位、特别是温室蔬菜不同部位各种元素的分配目前还没有研究清楚。利用同步辐射XRF法测定了温室油菜中各种微量元素中的分配情况。研究结果表明温室油菜中含有许多人体必需的微量元素,特别是Ca,Mn,Fe,Cu和Zn;但是不同的元素在叶片和根系的不同部位含量有所差异,总体上油菜根系中K,Ca和Mg的含量显著高于叶片,叶片中Fe,Zn,Co,Ni和Cu的含量则高于根系,其中侧根中的各种元素含量均很低。K,Ca和Co在叶片中间位置含量较高,由边缘向中部含量逐渐增加;Cu,Mn,Fe和Ni含量由叶片基部到叶尖处含量逐渐增高;Zn总体含量也比较均匀。在主根中各种元素普遍表现为根基部向根尖呈现先上升再降低的规律,根系中间部位各元素含量高,且普遍表现为根基部的含量要高于根尖处的含量。     

响应面法优化提取-原子吸收光谱法测定茶叶中的铅

研究超声辅助提取（UAE）快速测定茶叶铅。采用Plackett-Burman设计和响应面法得优化提取条件：200mg样品中加入HNO3∶H2O2（1∶1,V/V）5mL浸泡6min、78℃超声8.4min。对GBW 10016茶叶,该法测定值与标准值符合,加标回收率为96.0%—102.2%,检出限0.041μg.L-1,重复测定的RSD为6.3%。该法测定45个茶鲜叶和10种商品茶,铅含量（干基）在0.39—1.22mg.kg-1之间,与湿法消解（WAD）结果无显著差异。     

Evaluation of Motor Coordination and Antidepressant Activities of Cinnamomum osmophloeum ct. Linalool Leaf Oil in Rodent Model

Cinnamomum plants (Lauraceae) are a woody species native to South and Southeast Asia forests, and are widely used as food flavors and traditional medicines. This study aims to evaluate the chemical constituents of Cinnamomum osmophloeum ct. linalool leaf oil, and its antidepressant and motor coordination activities and the other behavioral evaluations in a rodent animal model. The major component of leaf oil is linalool, confirmed by GC-MS analysis. Leaf oil would not induce the extra body weight gain compared to the control mice at the examined doses after 6 weeks of oral administration. The present results provide the first evidence for motor coordination and antidepressant effects present in leaf oil. According to hypnotic, locomotor behavioral, and motor coordination evaluations, leaf oil would not cause side effects, including weight gain, drowsiness and a diminishment in the motor functions, at the examined doses. In summary, these results revealed C. osmophloeum ct. linalool leaf essential oil is of high potential as a therapeutic supplement for minor/medium depressive syndromes.