Crystal Structure of L-Quebrachitol

L-Quebrachitol (1) isolated from the root of Elaeagnus formosana Nakai (Elaeagnaceae) has not been reported before for any species of the genus of Elaeasnus. Its structure was established from spectral data and was completely characterized by single-crystal X-ray analysis. L-Quebrachitol crystallizes in the monoclinic system, space group P2₁, with cell parameters are a = 6.702(4), b = 7.207(4), c = 8.758(5) Å, β = 90.24(5)° and Z = 2.     

燕山东段野生木半夏果实性状的株间变异

以燕山东段碣石山天然分布的木半夏果实为试验材料,对其果实的8个性状变异和各性状间的相关性进行了分析研究。结果表明：（1）果实性状株间变异比较显著;（2）果实各性状变异系数由大到小依次为空瘪率、果实重、果形指数、果实横径、果梗长、种子重、果实纵径、果肉率;（3）果肉率与果实横径成极显著正相关,与果形指数成显著负相关;种子重与果实重成极显著正相关,与空瘪率、果实横径成显著负相关,与果实纵径关系最不紧密;（4）建议在野生木半夏群体中筛选高果肉率和高种子重的单株时应分别进行,以果实横径的大小作为主要参考指标;在以观果效果为主的单株选择上,则宜果梗长短为主要参考指标。     

内蒙古地区沙生植物--沙枣对亚硝酸盐分解作用的研究

利用分光光度法研究了内蒙古地区沙生植物———沙枣对亚硝酸盐的分解作用。结果表明,沙枣中富含的维生素C、维生素E和脯氨酸等抗氧化剂可以作为还原剂与亚硝酸盐作用,从而降低亚硝酸盐的含量;加入的沙枣量愈多,随时间延长对亚硝酸盐的分解能力亦增强,但不呈线性关系。试验结果表明,沙枣不仅可以作水土保持、防沙造林的先锋树种,还由于它富含抗氧化物,可作为人体降低体内亚硝胺生成的良好补充源。     

Changes in Physicochemical,Free Radical Activity,Total Phenolic and Sensory Properties of Orange (Citrus sinensis L.) Juice Fortified with Different Oleaster (Elaeagnus angustifolia L.) Extracts

In Iran and other parts of Western Asia, the oleaster (Elaeagnus angustifolia L.) fruit is processed in the dried powdery form, and in recent times, increasingly applied/sprinkled in fruit juices such as those made from oranges (Citrus sinensis L.). To our best knowledge, the effectiveness of oleaster fruit extract in fortifying the orange juice has not yet been reported and the knowledge of this will greatly benefit the consumers, particularly those around the Western Asia region. This current work, therefore, investigated the changes in physicochemical, free radical activity, total phenolic compounds, and sensory properties of orange juice fortified with different oleaster fruit extracts. The orange juice mix formulation comprised different concentrations (5, 10, 15, 20, and 25%) of oleaster (alcoholic, aqueous, and hydro-alcoholic) extracts. The control comprised orange concentrate (4% w/v), sugar (8.5% w/v), and citric acid (0.1% w/v) brought to the desirable volume with water. As the free radical activity depicted the antioxidant properties, the physicochemical aspects of this work involved the determinations of Brix, density, ash, pH, total acidity, sucrose, and total sugar, whereas the sensory aspects involved the determinations of color and taste. Whilst the aqueous oleaster 20 and 25% extracts produced notable physicochemical differences in the orange juice mix, both free radical activity, and phenolic compounds significantly increased (p < 0.05) after 30 days despite resembling (p > 0.05) those of control at day 1. More so, the increases in aqueous, alcoholic, and hydro-alcoholic oleaster extracts would decrease (p < 0.05) the sensory color and taste of the orange juice mix in this study.     

沙枣叶中总黄酮的含量测定

目的:沙枣叶中总黄酮的含量测定.方法:用721分光光度计测其吸光度.结果:沙枣叶在19.5～117.1μg/ml线性关系良好,平均回收率97.844%,RSD=3.56%.结论:本方法简便易行,重现性良好.     

长白山西坡小叶章种群迅速扩张对火灾风险的影响

本文选择长白山西坡林线下缘为研究区,采用样方调查方法,对各种植物的频度、盖度和生长高度等生态指标进行分析,应用常规统计方法揭示小叶章在群落中的地位与影响,分析小叶章种群迅速扩张可能带来的火灾问题,结果表明小叶章通过生长高度的竞争优势强烈排斥其他植物,增加盖度,成为这个地带的优势种。小叶章在春秋两季是易燃物质,很容易引起火灾。因此应该采取一系列措施应对这种情况,使保护工作不断升级,维系长白山生态系统。     

Studies on the diterpenoid constituents from Rabdosia angustifolia

Two new ent-kaurene diterpenoids, angustifolin B and natural hydrogen-bonded 1:1 complex, angustifolin C, as well as four known diterpenoids, angustifolin, isodonal, sodoponin, tri-chorabdal B, were isolated from the leaves of Rabdosia angustifolia.     

Determination of Total Sennosides and Sennosides A,B, and A1 in Senna Leaflets,Pods, and Tablets by Two-Dimensional qNMR

In the present work, a two-dimensional qNMR method for the determination of sennosides was established. Using band-selective HSQC and the cross correlations of the characteristic 10–10’ bonds, we quantified the total amount of the value-determining dianthranoids in five minutes, thus, rendering the method not only fast, but also specific and stability indicating. The validation of the method revealed excellent accuracy (recovery rates of 98.5 to 103%), precision (RSD values of 3.1%), and repeatability (2.2%) and demonstrated the potential of 2D qNMR in the quality control of medicinal plants. In a second method, the use of 2D qNMR for the single analysis of sennosides A, B, and A₁ was evaluated with acceptable measurement times (31 min), accuracy (93.8%), and repeatability (5.4% and 5.6%) for the two major purgatives sennoside A and B. However, the precision for sennoside B and A₁ was not satisfactory, mainly due to the low resolution of the HSQC signals of the two compounds.     

实心狭叶方竹秆形特性及变异规律研究

竹子的秆形结构研究对竹林资源产量测算和秆材的利用等具有重要的意义．本文对实心狭叶方竹的秆形特性及变异规律进行了研究．实心狭叶方竹平均秆高为116．9cm,最高可达257．0cm;地径一般在1cm以下,平均为0．495cm,最大可达1．58cm;节间长一般为5—18cm,平均为11．1cm,最长达20．2cm;枝下高一般小于70cm,平均为44．1cm．竹秆的地径与秆高、枝下高、竹秆重量、节间数等特征的相关性极为显著,其相关系数分别为：0．949,0．971,0．921,0．886,三次方程最能反映地径与秆高、枝下高、秆重、节间数等特征的相关性,不同于其他竹种的研究结果．节间长度在竹秆中随着秆轴的升高表现出逐渐升高→基本稳定→逐渐下降的规律．结果表明,不同竹子其秆形各因子之间的变化规律性不强,其研究还需进一步深入．