西洋参皂甙的核磁共振波谱研究——Ⅰ.西洋参叶中 Ocotillol型皂甙的结构分析

本文用常规一维~1H、~(13)C核磁共振波谱和远程异核化学位移相关谱。异核化学位移相关谱和同核化学位移相关谱技术研究了西洋参叶中首次分离出的一种Ocotillol型皂甙,确认了化学结构,并对其~(13)C、~1H NMR谱线进行了归属。     

Determination of cadmium in leaves by ultrasound-assisted extraction prior to hydride generation, pervaporation and atomic absorption detection

A flow injection-pervaporation approach, where the samples – beech or olive leaves – were introduced as slurry, has been used for continuous derivatization hydride generation and separation of cadmium prior to determination by atomic absorption spectrometry. The removal of the analyte is achieved with an 1 mol/l HCl + 16% H₂O₂ aqueous solution with the help of an ultrasound probe acting for 17 min. Thiourea and cobalt were also added to the slurry for kinetic catalysis of hydride generation. A CRM – beech leaves – where the analyte had not been certified but estimated was used for optimisation of the leaching step. The results obtained using direct calibration against aqueous standards demonstrated the reliability of the method. The linear concentration range of the calibration curve was from pg/ml to ng/ml, with a correlation coefficient, r², better than 0.99. The detection and quantification limits were 0.3 and 0.9 ng/ml, respectively. The relative standard deviation for within-laboratory reproducibility was 5.7%. Olive leaves CRM was used for validation.     

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.     

The Biological and Chemical Ameliorative Effects of Bread Substituted with Dried Moringa Leaves

This study conducted to evaluate the effect of additional dried moringa leaves on bread and their effects on the chemical and biological of rats fed it. Wheat flour with dried moringa leaves powder (DMLB) is used at different levels (6 and 9%) to produce moringa bread. We performed a sensory evaluation of wheat bread substituted with dried moringa leaves, chemical properties (approximate composition and antioxidants), microbiology (total bacteria, spore-forming bacteria, fungi, and yeast) and biological analysis (Triglycerides, total cholesterol, HDL and LDL, ALT, AST, urea, creatinine). Therefore, histopathology examination for kidney and livers of male albino rats fed fortified bread with dried moringa leaves compared with the control sample. The results of the approximate analysis showed significant differences by adding moringa leaves and the percentage of ash, protein, fat, and fiber increased with the moisture content. Moreover, carbohydrates decreased from fortified bread with dried moringa leaves compared to the control sample. The best treatment was fortified bread with 6% dried moringa leaves for all sensory evaluations compared to the other samples and moringa bread (DMLB 9%) helped reduce the microbial load during storage. The effect of moringa bread on liver cirrhosis was evaluated in rats induced by carbon tetrachloride CCl₄. We found out that the effect of moringa leaves on liver and kidney functions in a state of improvement, as for high-density lipoprotein (HDL) and low-density lipoprotein (LDL), the proportion of LDL was less than HDL compared to the control sample. At the same time, moringa leaves have a significant effect on reducing cholesterol, triglycerides, urea, and creatinine in the serum of rats, which may be attributed to the presence of biologically active plant components. It can be concluded that moringa leaves can improve biological and histological of rats feed it.     

无花果叶微量元素的分析

对无花果叶中微量元素进行了检测，结果表明：无花果叶含有微量元素锶、锰、铁、铜、锌、铬、镍、硒、钴，其中以铁、锌含量最高。同时还测定出镁、钙含量也极高。此与无花果果实所含的微量元素有很大的相似性和可比性，同样能用于防治癌症、痔疮等疾病，还可用于治疗糖尿病，具有较高的药用价值和开发优势。     

热水回流提取香椿叶多糖的工艺研究

研究热水回流提取香椿叶总多糖的工艺条件。单因素考察了原料粒度、提取温度、提取时间、料液比对香椿叶总多糖提取量的影响。以香椿叶总多糖提取量为考察指标,选用L9(34)试验设计对香椿叶总多糖的热水回流提取工艺条件进行优化,并验证最佳工艺条件、确定提取次数。其最佳工艺条件为:在原料粒度约为40目的条件下,提取温度为90℃,提取时间为3h,料液比为1∶25,提取次数为5次。在最佳参数组合下,每克香椿叶可提取总多糖为34.783mg。     

柞树叶和柞树皮中微量元素的测定

用高压罐消解样品,以正交试验原理,利用ICP-AES测定柞树叶及柞树皮中Zn、Fe、Mg、Ca、Se、K、Cu、Ge、P、Mn共10种微量元素的含量.方法回收率在96.00％-103.00％之间,相对标准偏差小于1.97％.ICP-AES具有简单、快捷,准确度高等特点,且多元素同时测定,更适合柞树叶、柞树皮中金属与非金属元素的分析测定.实验证明,柞树叶、柞树皮中含有Zn、Fe、Mg、Ca、Se、K、Cu、Ge、P、Mn等大量对人体有益的微量元素,说明柞树叶和柞树皮发展前景广阔.     

火焰原子吸收光谱法测定银杏叶中的5种微量元素含量

用火焰原子吸收光谱法对蚌埠市3个市区银杏叶片样品中的Fe、Zn、Mn、CuCd的含量进行测定.结果表明：银杏叶片样品中5种微量元素含量（μg/g）依次分别是蚌埠学院校园Fe394.2、Zn 22.4、Mn 12.7、Cu 8.5、Cd 5.4;龙子湖公园Fe 198.9、Zn 24.7、Mn 10.8、Cu 9.2、Cd 6.1;珠园Fe 395.6、Zn 32.5、Mn 23.5、Cu 18.9、Cd 18.9;回收率97.8％-102.1％.同一样品中银杏叶片各元素含量Fe＞Zn＞Mn＞Cu＞Cd,其中珠园样品中各微量元素的含量普遍较高.     

ICP-AES测定桔叶中锌和硼

桔叶经灰化、消解,ICP-AES测定微量锌和硼,相对标准偏差Zn:4.2%,B:2.7%,平均加标回收率Zn:98.57%,B:99.55%.该方法简便、快速,分析结果令人满意.