枸杞多糖提取工艺的研究

采用热水浸提法从枸杞干果中提取枸杞多糖,经正交实验确定浸提时间、温度、料水比最优值分别为：5h、100℃、1：40;微波预处理超过25min时,多糖得率达15．91％;醇沉时当醇沉时间为4h、乙醇加入量为4倍时有利于枸杞多糖提取。     

枸杞多糖的提取纯化及组成分析

采用水提法从枸杞中提取分离枸杞多糖(LBP)用DEAE纤维素柱色谱和凝胶柱色谱进行分离纯化,采用GPC-LLS法、红外光谱和气相色谱等方法对其组成进行研究。结果表明LBP含有3个级分,LBP的分子质量约为1.497×105,由阿拉伯糖(Ara),鼠李糖(Rha),木糖(Xyl),甘露糖(Man),半乳糖(Gal)和葡萄糖(Glc)6种中性单糖组成。     

NaCl与干旱双重胁迫下黑果枸杞幼苗对外源水杨酸的生理响应

干旱、盐分已成为限制植物生长发育的主要因子,在干旱与NaCl双重胁迫下植物的生长发育受到一定影响。为了探究黑果枸杞（Lycium ruthenicum）对盐旱逆境的适应性,该文采用盆栽试验,研究NaCl与干旱胁迫共同作用对其幼苗生长的影响,并观察盐旱逆境下黑果枸杞幼苗对外源水杨酸（SA）的生理响应,探究提高NaCl与干旱胁迫下黑果枸杞幼苗的存活率。结果表明：外源SA(0.1、0.5 mmol·L^-1)处理下,盐旱双重胁迫下黑果枸杞叶内可溶性糖、可溶性蛋白和脯氨酸含量有所增加,而丙二醛（MDA）含量显著降低（P<0.05）,过氧化氢酶（CAT）、过氧化物酶（POD）和超氧化物歧化酶（SOD）活性上升,且0.5 mmol·L^-1 SA处理效果优于0.1 mmol·L^-1 处理。综上结果可知,黑果枸杞对于轻度盐旱胁迫具有一定的适应能力,适宜浓度SA可提高盐旱逆境中黑果枸杞叶内渗透调节物质含量及抗氧化酶活性,该研究为进一步了解盐旱双重胁迫下黑果枸杞幼苗的生长发育提供相关理论依据。     

宁夏枸杞(Lycium barbarum)花器官形态多样性与品系间识别研究

该研究以42份宁夏枸杞(Lycium barbarum)为材料,对其中5个品系来自3个不同采集日期样品的花部性状进行了观察,同时对宁夏枸杞42个品系的16项花器官形态学指标进行了测定,并采用组间单因素方差分析法、主成分分析法和聚类分析法对宁夏枸杞种内的花部形态差异进行了研究。结果表明:宁夏枸杞花器官性状差异较大且多样性丰富,组间单因素方差分析表明宁夏枸杞花部性状在不同时间内采集无显著差异,即宁夏枸杞的花器官形态具有一定稳定性,因此可选用花器官形态作为区分宁夏枸杞种内不同品系的鉴别指标;主成分分析表明有关花瓣外缘色泽、花瓣正-背面脉络、花瓣形状、花瓣背部色泽、花喉色泽、雌雄蕊位置6个花部性状的累积贡献率达到84.791%,在宁夏枸杞品系的分类中起到了主要作用;聚类分析表明在欧式距离为7.5处可将枸杞的42个品系分成五类,能够将宁夏枸杞进行区分。该研究筛选出了能反映宁夏枸杞花器官形态差异的6个主要指标,并将42份宁夏枸杞分为五类,初步建立了宁夏枸杞种内品系间的形态学鉴别方法,可为宁夏枸杞的形态学研究及品系鉴定等提供依据。     

清水河枸杞，宁夏茄科一新种

描述了宁夏茄科枸杞属一新种,清水河枸杞。此新种与黑果枸杞相接近,但其枝条直伸,不成"之"字形曲折,花1~4朵簇生,花萼钟形或筒状钟形,花萼裂片边缘无毛,花冠筒部与冠檐近等长;雄蕊着生于花冠筒的喉部,花丝连同花冠无毛或被稀疏短柔毛;浆果扁圆球形,顶端常微凹,深红褐色;种子1~4枚而与后者不同。     

Association of ploidy and sexual system in Lycium californicum (Solanaceae)

In North American Lycium (Solanaceae), the evolution of gender dimorphism has been proposed as a means of restoring outcrossing after polyploidization causes the loss of self-incompatibility. Previous studies of this process in Lycium focused on comparisons between species that differ in ploidy. We examined intraspecific variation in floral morphology and DNA content in populations of L. californicum to determine correlations between sexual system and cytotype. We also used nuclear ITS and GBSSI sequence data to determine whether diploid and polyploid forms represent the same phylogenetic species, and the phylogeographic relationships among populations and ploidy levels. Within populations, no variation in ploidy was found, although among populations there was a perfect correspondence between sexual system and cytotype. Diploid populations were all hermaphroditic, whereas tetraploid populations were all gender dimorphic. There was no clear geographic pattern to the occurrence of diploid and tetraploid forms. Phylogenetic analysis confirms that L. californicum, regardless of ploidy, forms a monophyletic group within the genus Lycium. Sequences from diploid and polyploid individuals did not form reciprocally monophyletic clades, indicating either multiple gains of polyploidy, ongoing gene flow between cytotypes, or lack of lineage sorting since the evolution of polyploidy. The correspondence between ploidy and sex expression is consistent with the hypothesis that polyploidization triggers the evolution of gender dimorphism in this and other Lycium species.     

枸杞多糖LBP－I的分离纯化及性质鉴定

枸杞多糖ＬＢＰ－Ｉ的分离纯化及性质鉴定何进梁运祥张声华（华中农业大学生命科学技术学院,武汉４３００７０）（华中农业大学食品科学技术系）Ｉｓｏｌａｔｉｏｎ,ｐｕｒｉｆｉｃａｔｉｏｎａｎｄｐｒｏｐｅｒｔｙｉｄｅｎｔｉｆｉｃａｔｉｏｎｏｆｐｏｌｙｓａｃｃｈ...     

枸杞色素及多糖的不同提取次序对其得率及抗氧化活性的影响

为探究先后提取枸杞多糖及枸杞色素时对各自得率的影响。本研究通过分别考察这两种成分在提取过程中的提取溶剂、提取温度、料液比、提取次数及提取时间等因素对枸杞色素和枸杞多糖的得率影响,确定枸杞色素和枸杞多糖在提取次序不同时,两者的最佳提取工艺以及对DPPH·和·OH自由基清除率。结果表明,首先提取枸杞多糖后,枸杞色素的最佳提取工艺为采用正己烷,80℃时,料液比1∶10,提取2次,每次1 h,枸杞色素得率为2.48%,此时枸杞多糖得率为7.45%;而首先提取枸杞色素后,采用了超声辅助提取的方式提取枸杞多糖,发现超声效率为25%,料液比1∶10,提取20 min,枸杞多糖得率为5.23%,此时枸杞色素得率为3.93%。因此,首先提取枸杞多糖,使其平均得率为7.45%,而后提取枸杞色素,其平均得率为2.48%;总体上,枸杞色素1和枸杞多糖1对DPPH·自由基清除率都较高,枸杞多糖1对·OH自由基清除率较高,其抗氧化活性都接近Vc。     

不同灌水量对干旱区枸杞叶片结构、光合生理参数和产量的影响

宁夏枸杞是我国重要的药用植物资源.为确定宁夏枸杞的适宜灌溉量,在人工控水条件下,研究了不同月灌溉定额对宁夏枸杞叶片结构、光合生理以及果实产量的影响.结果表明：月灌水定额＜900 m³·hm^-2时,随着灌水量的增加,枸杞的叶面积、叶片厚度、栅栏组织厚度和叶片结构紧密度、叶片光合速率、瞬时水分利用效率、气孔限制值和枸杞果实产量显著增加,而气孔密度和胞间CO₂浓度则呈下降趋势;月灌水定额＞900 m³·hm^-2以后,叶片胞间CO₂浓度随月灌溉定额的增加呈上升趋势, 而叶面积、气孔密度和枸杞果实产量变化不显著,其他指标均呈相反的变化趋势.枸杞叶片蒸腾速率和气孔导度值以450 m³·hm^-2处理最高,分别达8.02和324 mmol·m^-2·s^-1;其他处理均低于对照.在节水条件下,900 m³·hm^-2的月灌溉定额较适合枸杞的灌溉.     

枸杞多糖抑制SMMC-7721肝癌细胞的VEGF表达、迁移与侵袭

目的研究枸杞多糖(lycium barbarum polysaccharide,LBP)对SMMC-7721肝癌细胞迁移、侵袭影响的机制。方法运用MTT法检肝癌细胞SMMC-7721的增殖率,Transwell检测细胞的迁移力和侵袭力,应用血管内皮生长因子(vascular endothelial growth factor,VEGF)小分子干扰RNA沉默VEGF表达,转染pcDNA 3.1-VEGF过表达VEGF,Western blot和qRT-PCR检测VEGF、MMP-2和MMP-9表达。结果 LBP(100、200、400μg/ml)处理可抑制SMMC-7721细胞的增殖、迁移和侵袭,并抑制MMP-2、MMP-9和VEGF表达;沉默VEGF可降低SMMC-7721细胞迁移、侵袭相关蛋白MMP-2和MMP-9水平,过表达VEGF可逆转LBP对SMMC-7721细胞迁移和侵袭相关蛋白MMP-2和MMP-9水平的抑制作用。结论枸杞多糖可抑制肝癌细胞的迁移和侵袭,其机制可能与直接抑制VEGF有关。     

Production of a hepatoprotective cerebroside from suspension cultures of Lycium chinense

Suspension cultures derived from Lycium chinense Miller seedlings produced significant amounts of a hepatoprotective cerebroside. Callus was induced from the stem of aseptic seedlings of L. chinense and maintained on MS solid media supplemented with 1.0 ppm 2,4-D and 0.1 ppm kinetin. Suspension cultures were established, and the cells were grown in the same liquid media in the dark. Lyophilized cells were extracted with a combined reagent of chloroform and methanol (2:1, v/v). An aqueous suspension of the evaporated cell extract was partitioned with chloroform, and the chloroform layer was subjected to silicic acid column chromatography followed by semi-preparative reverse phase C8 high pressure liquid chromatography. The purified compound showed hepatoprotective activity comparable to that shown by silymarin, and the structure was identified as 1-O-(β-d-glucopyranosyl)-(2S,3R,4E,8Z)-2-N-2′-hydroxy-(palmitoyl)-4,8-sphingadiene on the basis of spectral data. The content of the compound in cultured cell was tenfold higher than that of the fruit of L. chinense. The biosynthesis of the compound in cultured cell systems appears to parallel cell growth. Received: 12 June 1998 / Revision received: 30 July 1998 / Accepted: 14 August 1998     

宁夏枸杞柱头和萌发花粉中钙分布特征

用焦锑酸钾沉淀法对宁夏枸杞柱头和花粉中的钙离子分布进行了研究.结果显示,宁夏枸杞柱头表皮有一覆盖层,其中有许多含钙沉淀颗粒的小泡,当花粉落到柱头后从覆盖层中吸水,在萌发孔的表面上聚集了较多的钙沉淀颗粒.同时,花粉内部出现许多含钙的小液泡,使花粉体积增大,内部产生膨压,花粉萌发;生长在覆盖层中的花粉管顶端穿过覆盖层小泡时,附近聚集了较多的钙沉淀颗粒,在花粉管壁上也附着较多的细小钙沉淀颗粒.萌发的花粉粒中由大液泡占据,在其亚顶端的细胞质中,聚集较多钙沉淀颗粒的线粒体膨大形成了一些含钙沉淀颗粒的小液泡,由这些小液泡融合形成的大液泡,将花粉管细胞质挤到其顶端,使其极性生长.这是首次发现在植物柱头覆盖层中有钙离子的现象,从体内证明了钙离子在花粉萌发过程中的现象.讨论了枸杞柱头组织中钙的分布和花粉管的萌发与生长的关系.     

Effects of Physical and Chemical Factors on Induction Frequency of the Pollen Plantlet and Changes in Starch Formation in Anthers

Physical and chemical facttors affected distinctly induction frequency of the pollen plantlets from anther culture in vitro of Lycium. Experimental results showed that the anthers with their pollen grains at the uninucleate stage when the nuclei were centrally situated, were the best material for the anther culture. The different proportions of various hormones have affected the embryoid formation. When the MS medium was supplemented with 6-BAP (1 ppm) and NAA (0.1 ppm), the induction frequency was increased ( 16.9% ). When 3–15 per cent of sucrose was added in medium, the embryoids were induced and 15 per cent was the optimum. The callus of the filament was inhibited by the increase of the sucrose concentration. Before inoculation the anthers were pretreated at 3–5℃ for 4 days, the frequency of embryoid formation was efficiently increased in comparision with those of untreated anthers. The induction frequency of normal anthers was only 2.8 per cent, but that of the anthers pretreated was 3–9 per cent, the highest was 8.9 per cent .The changes of substances in anther pretreated and in normal anther was compared by means of histochemistry. Under normal conditions, there were a lot of starch accumulated in the inner wall Of the anthers and the distribution of the cytoplasm and the staining of the protein were even: In the anther pretreated, the starch grains have disappeared and the cytoplasm has condensed and the staining of the protein wasn't even. The differences may be related to induction, frequency of the anther culture.     

分光光度法测定地骨皮中牛磺酸含量

用分光光度法测定地骨皮中是否含有牛磺酸。在一定条件下,牛磺酸与乙酰丙酮和甲醛反应生成带色的配合物,建立了测定牛磺酸含量的分光光度法。结果表明,地骨皮中含有牛磺酸,已测定样品1中牛磺酸的质量分数为3.124 mg.g-1,样品2中牛磺酸的质量分数为6.203 mg.g-1,且样品2中的牛磺酸质量分数极显著高于样品1(p<0.01)。研究结果表明,地骨皮中含有牛磺酸,而且分光光度法成本低,干扰少,是测定地骨皮中牛磺酸质量分数的较好方法。     

枸杞的组织培养及植株再生的条件优化

目的:探讨枸杞组织培养及其植株再生条件的优化。方法:应用MS培养基为基本培养基,以各种不同激素配比进行枸杞愈伤诱导、分化诱导及根的诱导。结果:以枸杞叶片为外植体,利用2,4-D(2,4-二氯苯氧基乙酸)与KT(细胞分裂素)不同配比诱导出了愈伤组织。利用6-BA(6-苄基腺嘌呤)与NAA(α-萘乙酸)不同浓度的配比组合,成功地进行了杞再生芽诱导及根系诱导。结论:以MS培养基为基本培养基,并采用各种激素的不同配比,可以优化枸杞植株的再生条件。     

枸杞紫黄质脱环氧化酶(LcVDE)基因的克隆和分析

目的:克隆枸杞VDE基因的全长cDNA,通过对基因序列的生物信息学分析预测表达产物的结构特征和功能位点并验证其功能,为研究枸杞紫黄质循环的作用机理打下基础。方法:利用cDNA末端快速扩增和RT-PCR方法克隆枸杞VDE基因全长cDNA序列,生物软件分析VDE的生物学信息。构建VDE基因的原核表达载体pET-VDE,转化大肠后用IPTG诱导VDE过量表达;并构建体外反应体系对VDE表达蛋白酶功能进行验证。结果:LcVDE基因的ORF长1 413bp,编码的蛋白由470个氨基酸组成,分子量为53.61kDa,等电点为5.77。SDS-PAGE电泳结果表明,枸杞VDE基因在大肠杆菌中得到了过量表达。克隆基因表达蛋白进行紫黄质的脱环氧化反应,吸收光谱和HPLC的分析结果表明,表达蛋白催化了紫黄质的脱环氧化反应。结论:克隆得到的VDE基因编码的蛋白具有紫黄质脱环氧化酶的的功能与活性。