裸花紫珠提取物及其主要成分抗氧化活性研究

裸花紫珠是海南一种道地药材,具有消炎止血的功效。裸花紫珠富含黄酮类和苯乙醇苷类化学成分,它们已经被证实是天然抗氧化剂的主要来源之一。为了考察裸花紫珠药材的抗氧化活性,该研究采用DPPH.自由基清除法测定裸花紫珠醇提物、4个不同极性部位(石油醚、乙酸乙酯、正丁醇、水)及其7个主要成分的抗氧化作用。结果表明：裸花紫珠醇提物、醇提物的水部位、正丁醇部位、乙酸乙酯部位和化合物木犀草素、木犀草苷、毛蕊花糖苷具有较强的抗氧化活性,而5-羟基-3,7,3′,4′-四甲氧基黄酮的抗氧化活性则较弱。该研究结果为裸花紫珠的保健功能开发提供了依据。     

Glycopeptide dendrimers. Part I.

Glycopeptide dendrimers are branched structures containing both carbohydrates and peptides. Various classes of these compounds differing in composition and structure are mentioned, together with their practical use spanning from catalysis, transport vehicles to synthetic vaccines. The main stress is given to glycopeptide dendrimers, namely multiple antigen glycopeptides (MAGs). In MAGs, the core, branches or both are composed of amino acids or peptides. Other classes of glycodendrimers (PAMAM, polypropylene imine, cyclodextrin, calixarene, etc.) are mentioned too, but to a smaller extent. Their syntheses, physicochemical properties and biological activities are given with many examples. Glycopeptide dendrimers can be used as inhibitors of cell surface protein-carbohydrate interactions, intervention with bacterial adhesion, for studying of recognition processes, diagnostics, imaging and contrast agents, mimetics, for complexation of different cationts, as site-specific molecular delivery systems, for therapeutic purposes, as immunodiagnostics and in drug design. Biomedical applications of glycopeptide dendrimers as drug and gene delivery systems are also given.     

独一味总黄酮提取工艺优化

以独一味Lamiophlomis rotata总黄酮提取率为考察指标,比较乙醇回流法、水煎法、超声法三种提取方法优劣,并通过L9(34)正交试验优选出最佳提取条件。结果显示,乙醇回流法的黄酮提取率显著高于其他两种方法,其最佳提取工艺为用80%乙醇溶液回流提取3次,料液比为1∶50,提取时间25 min。     

Elucidating the role of oxidative stress in the therapeutic effect of rutin on experimental acute pancreatitis

Introduction: Acute pancreatitis (AP) may be severe and cause hospitalization or death, and the available treatment is insufficient to control pancreatic inflammation and pain. Rutin is a natural flavonoid with the potential to treat AP via anti-inflammatory, antinociceptive, and antioxidant activities.

Aim: This study investigated the beneficial effects of rutin on experimental AP induced by l-arginine administration in mice.

Methods: The l-arginine-induced AP model was used in Swiss mice (n?=?6–8). Mice submitted to AP induction were treated with rutin (37.5, 75, or 150?mg kg^?1, p.o.) or vehicle (saline) after 24, 36, 48, and 60?h of AP induction. Abdominal hyperalgesia, serum enzymes, interleukin (IL)-6 levels, pancreatic inflammatory parameters, malondialdehyde (MDA) levels, antioxidant enzyme activities, and 3-nitrotyrosine contents were measured 72?h after induction.

Results: Mice submitted to l-arginine injections developed abdominal hyperalgesia and increased serum amylase, lipase, C-reactive protein and IL-6 concentrations; and increased pancreatic myeloperoxidase activity, edema index, MDA, and 3-nitrotyrosine contents. A marked decrease in catalase activity was observed in the pancreas without alterations of superoxide dismutase (SOD) activity compared with the control group. Rutin treatment significantly impaired all the parameters that were altered by AP induction, but increased catalase and SOD activities in the pancreas compared with the vehicle-treated group.

Conclusion: Rutin treatment exerted a protective effect on l-arginine-induced AP by mechanisms involving the reduction of oxidative stress, which suggests that this flavonoid has a potential for future approaches designed for the management of AP.     

短叶假木贼中化学成分的分离和结构鉴定

从短叶假木贼(Anabasis brevifolia)的氯仿提取物中分离得到了9个化合物,经UVI、R、MS和NMR等波谱技术分析,并结合文献对照,确定其结构为-Ncis-feruloyltyramine(1)、N-trans-feruloyltyramine(2)、-Ncis-feruloyl-3-methoxytyramine(3)、-Ntrans-feruloyl-3-methoxytyramine(4)、3′,5,7-trihydroxy-4,′6-dimethoxy flavonoid(5)、eupatilin(6)、丁香脂素(7)、β-谷甾醇(8)、β-谷甾醇3-O-β-D-吡喃葡萄糖苷(9)。这些化合物均为首次从假木贼属(AnabasisL.)植物中分离得到。     

木蝴蝶化学成分研究

本文对木蝴蝶Oroxylum indicum(L.)Vent.种子的化学成分进行了研究,以85%乙醇加热回流提取木蝴蝶成熟种子,提取物经柱层析和重结晶手段分离,最终得到10个化合物,根据波谱学手段和理化性质,鉴定其结构分别为木蝴蝶苷B(1),木蝴蝶苷A(2),白杨黄素(3),白杨黄素-7-O-双葡萄糖苷(4),白杨黄素-7-O-β-吡喃半乳糖醛酸苷(5),芹菜素(6),羽扇豆醇(7),2α,3β-二羟基羽扇豆醇(8),豆甾醇(9),油酸(10),其中,化合物6～9为首次从木蝴蝶属植物中分得。     

基于转录组测序的滇山茶花叶呈色机理分析

该研究采用Illumina Hi-Seq2500高通量测序技术,对滇山茶的花叶(绿叶区和金叶区)的cDNA进行了转录组测序,分析滇山茶的花叶呈色机理。测序结果得到了228 862条单基因序列,筛选得到了4 851条差异表达基因。2 291条差异表达基因在GO数据库中有功能注释,1 826条差异表达基因被注释到COG数据库,这些差异表达基因被分为23个主要功能类别,其中大部分基因与滇山茶的生长和代谢有关。1 363条差异表达基因注释到了KEGG数据库,进一步筛选出了差异表达基因注释序列最多的15条代谢通路,其中卟啉和叶绿素代谢途径中的GluRS、δ-ALAD、ALAS基因和类黄酮合成途径中ANS、LAR、CHS基因与滇山茶的花叶形成密切相关。研究表明,滇山茶的花叶呈色是由于叶色相关代谢通路中大量的基因表达量发生变化引起的,并不是由单基因突变所致,病毒诱导的多个代谢途径基因沉默可能是滇山茶花叶呈色的主要原因。该研究丰富了滇山茶的转录组信息,并为滇山茶的彩叶品种培育提供了一定的参考。     

二乔玉兰开花过程中花色变化的生理生化机制

以4年生二乔玉兰不同花期外层花瓣为试材,测定其在开花过程中花瓣色度值、花色苷、类黄酮、可溶性糖含量、细胞pH值以及相关酶活性的变化,以探讨二乔玉兰花色呈色机理。结果显示:(1)随着花期的推移,苯丙氨酸解胺酶(PAL)和查尔酮异构酶(CHI)活性逐渐减弱,细胞pH值逐渐变大,可溶性糖、花色苷、类黄酮含量不断降低,而花瓣明亮度增强,红色度以及彩色度减弱,且不同花期各参数值之间差异显著。(2)花瓣可溶性糖含量、PAL和CHI的活性与其花色素苷、类黄酮含量变化之间呈显著正相关关系,花瓣pH值的变化、明亮度L*值与花色素苷、类黄酮含量之间呈显著负相关,色相值a*与花色苷含量的变化呈显著正相关。研究表明,二乔玉兰花瓣花色苷和类黄酮含量的高低可以影响其花色的深浅,可溶性糖含量、PAL和CHI活性、细胞pH通过参与一定的生理代谢来调节花色素的形成,进而引起二乔玉兰花色色调的改变。