马蹄香的保护生物学研究

马蹄香是我国特有的单种属植物,也是一个受威胁的物种,被列为国家级重点保护植物。作者调查了马蹄香在陕西秦巴山区的分布、生境及其现状,论述了它的保护价值,重点分析了致濒原因,提出了以就地保护与迁地保护相结合,以就地保护为主,积极进行分株繁殖,以实现在其原产地恢复和发展种群为最终目的的保护措施。     

马蹄香的形态组织学研究

报道了马蹄香的药材性状和形态学,组织学特征,为准确鉴定该药材及研究本属植物的系统分类提供了依据。     

松属植物种子油脂肪酸的分布及化学分类探讨

用气相色谱-质谱(GC-MS)方法分析了6种双维管束松亚属树种:赤松(Pinus densiflora Sieb.etZucc.)、黑松(P.thambergii Parl.)、油松(P.tabulaeformis Carr.)、巴山松(P.henryi Mast.)、黄山松(P.taiwanensis Hayata)、马尾松(P.massoniana Lamb.)和2种单维管束松亚属树种:白皮松(P.bungeanaZucc.)及红松(P.koraiensis Sieb.et Zucc.)的种子油脂肪酸成分。结果表明这8种松属植物的种子油脂肪酸成分有相似的分布情况:最主要成分都是亚油酸C_(18:2(9,12));都同时含有3种Δ~5的不饱和脂肪酸:C_(18:2(5,9)),C_(18:3(5,9,12))和C_(20:3(5,11,14))。这两个特征可以作为松属(Pinus L.)的化学分类证据。结果还表明同一属内各种间的种子油脂肪酸成分无明显差别。     

Eleutheroside K isolated from Acanthopanax henryi (Oliv.) Harms suppresses methicillin resistance of Staphylococcus aureus

Acanthopanax (A.) henryi (Oliv.) Harms contain many bioactive compounds commonly used in traditional Chinese medicine. The objective of the present study was to investigate the antibacterial activity of the single constituent, Eleutheroside K (ETSK) isolated from the leaves of A. henryi (Oliv.) Harms, against methicillin-resistant Staphylococcus (S.) aureus (MRSA). Broth microdilution assay was used to measure the minimal inhibitory concentration (MIC) and the MIC values of ETSK against eight clinical S. aureus strains were all 50 µg ml⁻¹. At sub-inhibitory concentrations, a synergistic effect between oxacillin (OXA) and ETSK was confirmed using checkerboard dilution assay and time-kill curve analysis. The bacteriostatic effect became more pronounced when ETSK was used in combination with detergent (Triton X-100) or ATPase inhibitor (N, N′-dicyclohexylcarbodiimide). According to western blot analysis, the down-regulated expression of Penicillin-binding protein 2a (PBP2a) further validated that the bacterial activity was inhibited when treated with ETSK in a dose-dependent manner. Results based on our study verified that ETSK significantly suppressed MRSA infections and emphasized the potential application of ETSK as a novel anti-MRSA natural drug.     

锥栗不同品种果实营养成分分析初报

对福建建瓯9个锥栗主栽品种的果实进行营养成分分析。结果表明,其果实营养成分均以淀粉、糖类为主,并含有较丰富的蛋白质、脂肪、纤维、维生素C及Ca、K、Mg、Mn等矿质元素;品种间多项含量值差异明显。     

陕西省4种新记录植物

报道了陕西省4种新记录植物,分别是总序香茶菜[Isodon racemosus(Hemsley)H.W.Li]、绵毛金腰[Chrysosplenium lanuginosumJ.D.HookerThomson.]、紫花娃儿藤(Tylophora henryi Warburg)、球果假沙晶兰[Monotropastrum humile(D.Don)H.Hara]。对于补充完善陕西植物资源,研究秦岭植物区系有重要意义。凭证标本存于西北农林科技大学植物标本馆(WUK)。     

Polycyclic Polyprenylated Acylphloroglucinols and Chromone O‐Glucosides from Hypericum henryi subsp. uraloides

Two new C(30)‐epimeric polycyclic polyprenylated acylphloroglucinols (PPAPs), named uralodins B and C ( 1 and 2 , resp.), were isolated from the aerial parts of Hypericum henryi subsp. uraloides together with two new chromone glucosides, urachromones A and B ( 3 and 4 , resp.), as well as 16 known compounds. Their structures were established by extensive NMR techniques and MS analysis. The epimers 1 and 2 always behaved like a single compound when examined by TLC, and were separated by HPLC. Their configuration was distinguished by comparative analysis of the NMR data with known analogues together with the ROESY experiment. All the isolated PPAPs were evaluated for their cytotoxic activities against HepG2, SGC7901, HL‐60, and K562 cell lines. Compound 1 showed modest cytotoxic activities against SGC7901 and HL‐60 cell lines, and 2 showed modest cytotoxic activities against HepG2, SGC7901, HL‐60, and K562 cell lines.     

香果树花及胚胎发育的细胞学研究

香果树为茜草科香果树属单种属植物,是我国特种古老珍稀濒危树种。对香果树大小孢子发生及胚胎发育过程进行了细胞学观察,观察结果表明：香果树子房两室,中轴胎座,胚珠多数,倒生,单珠被,厚珠心。大孢子四分体排列成线性,靠近合点端的大孢子发育成功能大孢子,珠孔端的3个退化,胚囊发育为蓼型,典型的七胞八核胚囊。雄蕊浅黄色,蝶形花粉囊,小孢子四分体成四面体型,成熟的花粉为二胞花粉。胚胎发育过程经历了合子、原胚、球形胚、心形胚、鱼雷胚5个阶段,种子成熟时,胚发育未完全成熟。本文在香果树大小孢子发生发育切片的观察中未发现异常现象,胚胎发育停留在鱼雷胚时期。     

栾树黄酮类化合物的提取及微乳薄层色谱分析

在单因素试验的基础上,用正交试验法对栾树叶中黄酮类化合物提取的最佳条件进行了研究,结果表明,用70％乙醇,料液比为1：10(W／V),在75(、下回流提取3次,每次2h,提取率高。以十二烷基硫酸钠(SDS)-正丁醇-正庚烷水按11.7：15．6：2．7：70．0的比例组成的O／W型微乳液,可使栾树黄酮类化合物分离完全．分离效果好。从栾树叶中分离得到11个黄酮斑点,果实中分离得7个黄酮斑点,果壳中分离得8个黄酮斑点。     

小草蔻花部维管束系统的解剖学研究

小草蔻花梗的维管束可分成外环和中心区两部分。进入室下区后,外环维管束向外偏移,其数目由约13束增加至约40束;中心区由不规则分布的18束变为三角形排列的12束。延伸至子房室区时,外环基本不变,而原来中心我的维管束则成为3束心皮背束、3束隔膜束及5－7束小的胎座维管束。3束心皮背束外方的主支经延长中最后进入花萼、胎座维管束于延长部基部消失。及至延长部基部,3束隔膜束的内侧横向分支,并最后与部分外环的维管束及心皮背束方的细小分支在此形成一个维管束网结,而外侧的主支直接向上延伸;近轴面的隔膜束主支分裂成4支最后进入仅有的1枚功能雄蕊,无轴面的2束隔膜束主支则各分成2－3束最后进入唇。延长部的维管束网结部分延伸入花瓣、唇瓣和腺体基部,少量进入花柱。首次提出姜科植物的花萼既代表了3枚花萼片,又包含了3枚缺失的外轮雄蕊。支持姜科的唇瓣代表了两枚缺失的内轮雄蕊及两枚腺体是隔膜腺变异结构的观点。