白花地胆草的抗菌活性成分研究

从白花地胆草(Elephantopus tomentosus Linn.)全草的乙醇提取物中分离得到9个化合物,通过波谱分析,鉴定其结构分别为:表木栓醇(1)、羽扇豆醇(2)、6-deoxyisojacreubin(3)、桦木酸(4)、熊果酸(5)、阿魏酸(6)、3-甲酰吲哚(7)、半夏酸(8)和30-醛基羽扇豆醇(9)。所有化合物均为首次从白花地胆草中分离得到。用滤纸片琼脂扩散法测定上述化合物的抗菌活性,结果表明,化合物6和7对金黄色葡萄球菌的生长有抑制作用,化合物6和8对烟草青枯病菌的生长有抑制作用。     

中国地胆草属和假地胆草属(菊科)分合的分子依据

为探讨中国菊科地胆革属和假地胆草属在DNA分子水平上的亲缘关系以及这两个属的分合问题,以香港野生的地胆草属植物地胆草（ElephantopusscaberL）、白花地胆草（E.mollisHK．B）和香港、台湾归化的假地胆草属植物假地胆草（Pseudelephantopusspicatus（BJussexAublet）CF.Baker）为材料,选取6种18－24mer和5种10mer的随机单引物进行任意引物PCR（AN－PCR）和随机扩增多态DNA（RAP）分析,以相似没指数值作亲缘关系分析。初步结果显示：2种地胆草与1种假地胆草之间的DNA指纹图谱差异较大,提示地肥草属与假地胆草属植物的亲缘关系较远,属于属间差异。这与形态学、组织学和细胞学结果呈相关性,认为这两个属合并成一个广义的地胆草属是不合适的。     

工业生产ABA发酵液中脂溶性成分的GC/MS分析

利用气相色谱质谱联用技术,首次对工业生产脱落酸的发酵液中脂溶性成分进行分析,经气相色谱分离出了55个峰,共鉴定了其中的36种化学成分,占总成分的72.80%。分析鉴定结果表明,发酵液的脂溶性成分中主要化学成分为饱和烃类,如十四碳烷至三十一碳烷,占总脂溶性成分的27.49%;其次是脂肪酸酯,如十五碳酸乙酯、棕榈酸乙酯、油酸乙酯与亚油酸乙酯等,占总脂溶性成分的19.02%。     

地胆草属药用植物研究进展

菊科地胆草属植物被广泛用于多个国家或地区的传统医药中,该属中的地胆草(Elephantopus scaber)具有清热、凉血、利湿的功效;我国多个民族也用来治疗感冒、肾炎、肝炎以及虫蛇咬伤等多种伤病。该属植物含有多种化学成分,按结构类型主要有倍半萜烯内酯、三萜、甾体、黄酮等化合物。现代药理研究证明该属药用植物粗提物及单体具有抗菌消炎、抗病毒、抗原虫以及抗肿瘤等多种生物活性。本文系统综述了该属药用植物传统知识、化学成分及生物活性的研究进展,可为该属植物的进一步开发利用提供参考。     

见血封喉乳汁脂溶性成分及其抗氧化活性研究

首次采用气相色谱.质谱联用技术(GC-MS)对见血封喉(Antiaris toxicaria(Pers.)Lesch.)乳汁的脂溶性成分进行了分析,共鉴定了27个化学成分,占其总量的91.7%.用清除DPPH自由基能力的方法测定了见血封喉乳汁脂溶性部位的抗氧化活性,结果显示出一定的抗氧化活性,SC50值为500μg ml-1.     

青枣核果木枝叶乙酸乙酯段脂溶性成分GC-MS分析

采用溶剂提取法和硅胶柱层析法分离青枣核果木乙酸乙酯部位,得到脂溶性提取物I和II,并结合气相色谱-质谱联用技术对其化学成分鉴定与分析。从提取物I中鉴定出15种化学成分,主要为酯类化合物(61.54%);从提取物II中鉴定出32种成分,成分种类多,以萜类化合物最多(19.72%)。首次对青枣核果枝叶乙酸乙酯部位脂溶性成分研究,发现其含有重要的化学制品原料:如油酸乙酯与橙花叔醇,并含有丰富的重要活性物质—角鲨烯和信息素抗虫剂。     

地木耳中脂溶性物质抑菌活性研究

采用索氏提取法从地木耳中提取脂溶性物质,经硅胶柱层析将脂溶性物质分离成石油醚洗脱组分(非极性脂)、苯洗脱组分(弱极性脂)和乙醇洗脱组分(强极性脂),并对脂溶性物质和3种洗脱组分进行抑菌活性研究,以促进地木耳的综合应用。结果表明,地木耳中脂溶性物质含量为2.62%。其中,非极性石油醚洗脱组分含量最高,占总脂的54%,但无抑菌活性;强极性的乙醇洗脱组分含量其次,占总脂的32%,其抑菌活性最强;弱极性苯洗脱组分含量最低,占总脂的14%,有弱抑菌活性。地木耳脂溶性物质对6种菌有较好的抑制作用,其抑制能力大小为:大肠杆菌金黄色葡萄球菌枯草芽孢杆菌黑曲霉酿酒酵母假单胞杆菌。     

白木香内生真菌Aspergillus sp.A14的挥发性成分及其抗菌活性

通过溶剂萃取法提取白木香内生真菌A14(Aspergillus sp.)的挥发油,采用滤纸片琼脂扩散法分别测定了其对3种人体病原菌的体外抑菌活性。结果表明:A14挥发油对金黄色葡萄球菌(Staphylococcus aureus)、耐甲氧西林金黄色葡萄球菌(Methicillin-resistant S.aureus,MRSA)和白色念珠菌(Candida albicans)均表现出一定抑制作用。应用GC-MS技术,分析鉴定了内生真菌A14挥发油的14个化学成分,显示蜂蜜曲菌素是其中的主要成分,占挥发油峰面积的93.41%。     

泡桐花油的GC-MS分析及抑菌作用研究

本文采用索氏提取法提取泡桐花脂溶性成分,并用GC-MS联用技术对其成分进行分离鉴定.共分离出45个组分,各组分提取质谱图,经用人工解析及NIST05标准谱库检索定性,峰面积归一化法定量分析,计算出各成分的相对百分含量.其中含量较高的化学成分有3,7,11,15-四甲基十六-1,6,10,14-四烯-3-醇(14.74%)、二十三(碳)烷(5.79%)、9,19-环羊毛甾-24-烯-3-醇(5.41%)、十六(烷)酸(5.09%)、十六烷基环氧乙烷(4.93%)等.对泡桐花索氏提取后的部分进一步水提,并分别测定其脂溶性成分和水溶性成分对大肠杆菌、金黄色葡萄球菌的体外抑菌作用.得知其脂溶性成分对金黄色葡萄球菌抑制作用较强,而水溶性成分则对大肠杆菌抑制作用较强.本次实验,可为泡桐花资源的进一步开发利用提供一定的理论依据.     

天竺桂挥发油化学成分及抑菌活性研究

用水蒸馏法提取天竺桂(CinnamomumjaponicumSibe)挥发油,并用GC-MS分析化学成分,用滤纸片法测其抑菌活性。结果表明,从天竺桂挥发油中分离出27种化学成分,以冰片为主要成分,占26.03%;抑菌实验中,挥发油对大肠杆菌、枯草杆菌和金黄色葡萄球菌都有明显的抑菌作用。     

Two new germacranolides from Elephantopus tomentosus

The bioassay-guided chemical investigation of the whole plant of Elephantopus tomentosus led to the isolation of two new germacranolides, tomenphantopin C (1) and tomenphantopin D (2), together with four known compounds (3–6). Their structures were determined by spectroscopic techniques (UV, IR, MS, 1D and 2D NMR). All compounds were evaluated for cytotoxic and antibacterial activities.     

A new sesquiterpene lactone from Elephantopus scaber

A methanolic extract of the plant Elephantopus scaber was found to contain lupeol, stigmasterol and a new germacranolide dilactone 11,13-dihydrodeoxyelephantopin.     

Chemical constituents from the roots of Elephantopus scaber L.

A chemical investigation of the roots of Elephantopus scaber L. led to the isolation of thirteen compounds, including four sesquiterpenoids (5, 6, 7, 8), two phenols (1, 2), three triterpenoids (9, 10, 11), two caffeoylquinic acids (3, 4), one alkaloid (12), and one sterol (13). Among these molecules, compound 2 (2-butenoic acid, 3-methyl-[4-(1,5-dimethyl-4-hexenyl)-3-hydroxyphenyl] methyl ester) was identified for the first time from this species, while compounds 1 (curcuphenol) and 12 (patriscabratine) were isolated for the first time from the genus Elephantopus.     

地胆草倍半萜内酯化合物体外抗肿瘤作用的研究

采用四甲基偶氮唑盐比色法和琼脂糖凝胶电泳法等研究地胆草倍半萜内酯化合物scabertopin(1)和isodeoxyelephantopin(2)在体外对SMMC-7721、Hela和Caco-2三种肿瘤细胞增殖的影响.发现这两个化合物在1～100 μM浓度内对三种肿瘤细胞增殖有显著的抑制作用,且呈一定剂量依赖关系.二者抑制SMMC-7721细胞增殖的IC50值分别为29.27和9.54 μM;抑制Hela细胞增殖的IC50值分别为22.19和25.39 μM;抑制Caco-2细胞增殖的IC50值分别为35.99和25.76 μM.时效性实验还显示2对Hela细胞增殖的抑制作用呈时间依赖关系.2浓度100 μM作用Hela细胞48 h,琼脂糖凝胶电泳显示明显的细胞凋亡"梯状"条带(DNA ladder),提示isodeoxyelephantopin抑制Hela细胞作用是通过诱导其凋亡.     

Chemical composition of the essential oil of Elephantopus scaber from Southern China

The essential oil of Elephantopus scaber, a famous medicinal herb from Yangjiang County in Southern China was analyzed for the first time using GC-MS. The major constituents were hexadecanoic acid (42.3%), isopropyl dimethyl tetrahydronaphthalenol (14.1%), beta-sesquiphellandrene (8.3%), octadecadienoic acid (5.5%), and phytol (5.2%).     

A novel Steroid from Elephantopus scaber L. an Ethnomedicinal plant with antidiabetic activity

Acetone extract of Elephantopus scaber, an ethnomedicnal plant, reduced the blood glucose levels in streptozotocin-induced diabetic rats significantly. Acute toxicity studies revealed the non-toxic nature of the crude extract. Fractionation of the acetone extract yielded a new steroid, 28Nor-22(R)Witha 2,6,23-trienolide. Biological testing of the compound demonstrated a significant antidiabetic activity by reducing the elevated blood glucose levels and restoring the insulin levels in streptozotocin-induced diabetic rats. This compound can be a useful candidate to treat diabetes.     

Plant regeneration from organogenic callus and assessment of clonal fidelity in Elephantopus scaber Linn., an ethnomedicinal herb

An efficient callus induction and plant regeneration system has been standardized for an ethnomedicinal plant, Elephantopus scaber Linn. Two explants i. e. seeds and leaf segments were used for callus induction. Murashige and Skoog (MS) medium supplemented with 5.0 μM 2, 4-dichlorophenoxy acetic acid (2, 4-D) and 0.5 μM kinetin (Kn) gave the optimum frequency (89 %) of callus induction from seed explant. The results showed that the highest response in terms of percent callus regenerating (91 %) and number of shoots (56) per culture was recorded on MS medium supplemented with 6.0 μM N₆-benzylaminopurine (BA) and 1.5 μM α naphthalene acetic acid (NAA). The best rooting of regenerated shoots was obtained on half strength MS medium supplemented with 6.0 μM indole-3- butyric acid (IBA). On this medium, 100 % of the shoots produced roots with a mean number of 3.2 roots per shoot. The positive role of vesicular arbuscular mycorrhizae (VAM) along with potting mix has been well established in the present study. Of the various potting mix employed for plant acclimatization, the highest response of 100 % plant survival was noticed when autoclaved garden soil, sand (2:1) and VAM was utilized as potting mix. Inter-simple sequence repeats (ISSR) were used to establish the clonal fidelity of regenerated plantlets and the banding profiles from callus derived plants were monomorphic and similar to those of mother plant, thus ascertaining the true-to-type nature of these plants.     

Deoxyelephantopin from Elephantopus scaber L. induces cell-cycle arrest and apoptosis in the human nasopharyngeal cancer CNE cells

Infection of influenza virus could induce acute lung inflammatory injury (ALII) that was at least partially caused by excessive innate immune responses. To study whether down-regulating Toll-like receptor (TLR)-mediated innate immune response could lessen influenza virus-induced ALII, a microsatellite DNA mimicking oligodeoxynucleotide (MS ODN), named as SAT05f capable of inhibiting TLR7/9-activation in vitro, was used to treat mice infected with FM1 virus. In parallel, two MS ODNs confirmed with less or no in vitro activities, named as MS19 and MS33, were used as controls. Unexpectedly, SAT05f failed to lessen ALII in the mice, whereas MS19 significantly inhibited the weight loss and displayed dramatic effect on lessening the ALII by reducing consolidation, hemorrhage, intra-alveolar edema and neutrophils infiltration in lungs of the mice. Meanwhile, MS19 could decrease the mortality of influenza virus infected mice and down-regulate TNF-α production in their lungs. The data suggest that MS19 might display its therapeutic role on ALII induced by influenza virus by reducing over-production of TNF-α.     

Genetic diversity and population structure in Elephantopus scaber (Asteraceae) from South China as revealed by ISSR markers

Abstract

We used inter-simple sequence repeat (ISSR) markers to investigate genetic variation in eight natural populations of Elephantopus scaber from South China, including Guangdong, Hainan and Hong Kong. Eleven primers produced 247 bands across all 184 individuals, of which 243 (98.4%) were polymorphic. The average genetic diversity at the species and population levels was estimated to be 0.283 and 0.103, respectively, using mean expected heterozygosity. The average gene differentiation (F _ST) among populations was 0.725. AMOVA analysis showed that the partition of molecular variation between and within populations was 72.5% and 27.5%, respectively. The effective number of migrants among populations based on the F _ST was relatively low (N _m = 0.095). Cluster analysis based on Nei's genetic distance and the neighbour-joining method revealed the genetic relationships among the populations of E. scaber. The Mantel test indicated that there was no significant correlation between population genetic and geographic distances. The results obtained from the AMOVA analysis, the cluster analysis, and the Mantel test all suggested that fragmented local environments and human disturbance might play important roles in shaping the population structure of E. scaber.