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1.
Sun ZL  Gao GL  Luo JY  Zhang XL  Zhang M  Feng J 《Fitoterapia》2011,82(3):401-404
Constituents of the fruits of Peatasites tatewakianus were investigated. A new compound, namely bakkenolide-VI (1), was isolated. The structures was elucidated on the basis of 1D, 2D NMR, TOF-MS and ESI-MS techniques, and physicochemical properties. The neuroprotective activity of the new compound was assayed with primary cultured neurons exposed to oxygen-glucose deprivation and oxidative insults.  相似文献   

2.
Fractionation of an antiplasmodial ethanolic extract from the aerial parts of Vitex cauliflora led to the isolation of the new labdane diterpene 1 together with the known triterpene uvaol. The structure of the new compound 1 was established as 3-oxo,15,17,18-triacetoxy-labda-7,13E-diene on the basis of spectroscopic data (1D and 2D NMR, MS).  相似文献   

3.
基于GIS的云南省印度黄檀造林区划研究   总被引:3,自引:2,他引:1       下载免费PDF全文
根据试验点印度黄檀与气候条件的关系,分析确定了印度黄檀的气候区划指标。利用云南省的气象数据,在SPSS支持下,进行线性回归分析建立区划指标的空间分析模型。在GIS的支持下,按1 km×1 km细网格推算出云南省其它地区印度黄檀树高、胸径的生长情况,并对印度黄檀的适宜种植区进行区划,以气候因子为条件,得出云南省适宜种植印度黄檀的土地面积占32.5%,其中,最适宜面积占0.7%,较适宜面积占7.4%,一般适宜面积占24.4%。  相似文献   

4.
A new bakkenolide and a known one were isolated from Petasites tatewakianus. The structure of the new compound was elucidated on the basis of spectroscopic methods including IR, EIMS, HRESIMS, 1D and 2D NMR, and the known compound was established by single crystal X-ray structural analysis. The in vitro cytotoxic activity of these two compounds against cultured human cervical carcinoma (HeLa), human breast cancer (MCF-7) and murine Lewis lung carcinoma (LLC) cell lines was also evaluated.  相似文献   

5.
麻竹枝叶生长对钩梢的响应   总被引:1,自引:0,他引:1       下载免费PDF全文
为了解冠层生物量积累、分配及枝叶大小对麻竹立竹受营林措施干扰(钩梢)后的响应,对不同竹龄全梢、钩梢麻竹地上构件生物量、生物量比、单叶特征、大小枝生物量分配比例及商品竹叶数量进行了调查.结果表明:麻竹立竹地上现存生物量分配格局为秆>枝>叶.叶生物量、叶/枝和叶/秆生物量比为2年生>3年生>1年生.随着竹龄的增加,枝、秆生物量、地上生物量和枝/秆生物量比总体上呈增加的趋势.2年生和3年生立竹枝、叶生物量分配比例显著高于1年生立竹,秆生物量分配比例显著小于1年生立竹.此外,随着竹龄的增加,立竹减少了对0 ~8 mm枝生物量的分配,增加了对8~16 mm、16 mm以上枝生物量的投入,以提高空间拓展能力,截获更多光资源.钩梢强烈影响了生物量分配格局,显著减小了麻竹立竹枝、叶、秆、地上生物量.钩梢后麻竹立竹增加了枝、叶生物量分配比例,减少了秆生物量的分配比例,同时提高了单叶叶面积和单叶干质量,增加了8~16 mm、16 mm以上枝生物量分配比例,减小0~8 mm枝生物量分配比例,以权衡枝叶的生长,提高立竹对环境的适合度.钩梢后立竹叶/枝、叶/秆、枝/秆生物量比升高,表明生物量分配更多地向叶和枝倾斜.钩梢麻竹商品竹叶数量较全梢麻竹增加29.68%,且发生部位明显降低,钩梢后冠层下部商品竹叶数量增加79.73%,中部商品竹叶数量增加25.81%,降低了采摘高度.在钩梢后的一个生长季内,钩梢影响了麻竹立竹资源利用策略,表现为枝与叶之间关系的变化,但随钩梢年限的增加其变化规律如何尚需进一步研究.  相似文献   

6.
Xu J  Jin D  Shi D  Ma Y  Yang B  Zhao P  Guo Y 《Fitoterapia》2011,82(3):508-511
As a part of our ongoing search for plant-derived compounds that inhibit nitric oxide production, the methanol extract of the roots of Vladimiria souliei was found to show significant inhibitory effects on INF-γ-induced nitric oxide production in murine macrophage RAW264.7 cells. Bioactivity-guided isolation of the extract yielded two most active sesquiterpenes, including a new compound, named souliene A (1) and alismol (2). Their structures were elucidated by spectroscopic methods (IR, ESIMS, HRESIMS, 1D and 2D NMR). Two isolates showed promising inhibitory effects on INF-γ-induced nitric oxide production in murine macrophage RAW264.7 cells.  相似文献   

7.
巨龙竹资源分布特点及其开花结实现象   总被引:4,自引:4,他引:0       下载免费PDF全文
巨龙竹Dendrocalamus sinicus Chia et J. L. Sun是云南特有的重要经济竹种之一,为了保护和开发巨龙竹资源,本文调查了18个典型的巨龙竹种群,并对近6年来巨龙竹开花结实现象进行了分析。研究结果显示巨龙竹分布区域十分狭窄,以滇西南的沧源、西盟和孟连3个县为中心,集中分布于22°09' 23°30 'N,98°56' 99°37' E,海拔1 000~1 500 m之间的低中山区。同时,巨龙竹秆型依照分布区由南向北表现出明显的弯曲型——弯曲型与通直型混生(混生型)——通直型的变化趋势。种群平均胸径与分布区海拔之间呈现极显著的正相关关系。巨龙竹野外多见零星开花,以通直型为主,但结实少见且结实率低,约为0.34%~0.64%,这可能主要是由于个体零星开花以及小花雌雄异熟等原因造成的结果。土蜂Apis cerana Fabricius的访问可能是巨龙竹有性繁殖中传粉的重要补充方式。  相似文献   

8.
Identification of medicinal plants by their molecular signature is a fast growing tool. The identification of Desmodium gangeticum (L.) DC. (Shalparni, a constituent of Ayurvedic formulation “Dashmoolarishtha”) was carried out using genomic approach. Authentic samples of D. gangeticum(L.) DC., D. velutinum (Willd.) DC. and D. triflorum (L.) DC. were analyzed and compared to commercial samples of various origin. Within twenty primers used, eleven gave 223 RAPD fragments. RAPD profiles of three species showed very low similarity index (0.21–0.39), whereas market samples showed high similarity of 0.82–0.89 with authenticated D. gangeticum.  相似文献   

9.
Zhang L  Ma ZZ  Che YY  Li N  Tu PF 《Fitoterapia》2011,82(2):267-271
A new amide, N-(3,4-dihydroxybenzoyl)-3,4-dihydroxybenzamide (1), was isolated from the Pu-erh tea made with the leaf of Camellia assamica (Mast.) Chang by special fermentation techniques with bacteria and fungus. Its structure was established by means of spectroscopic data analyses, including mass spectrometry and both 1D and 2D NMR spectroscopy. Human micro-vascular endothelial cell (HMEC) injured with H2O2 was used as the model to test protective effect of compound 1 in contrast with other known compounds isolated from Pu-erh tea. These results suggested that compound 1 is a very useful compound to prevent H2O2-induced cell death of HMEC.  相似文献   

10.
Four new flavonoids (14) were isolated from the leaves of Morus mongolica. The structures were determined on the basis of the spectroscopic methods including UV, IR, HR-ESI-MS, 1D and 2D NMR.  相似文献   

11.
Phytochemical investigation of Laureliopsis philippiana resulted in isolation of a new bisbenzylisoquinoline alkaloid (1) named laureliopsine A. The structure was established by spectroscopic methods, including 2D homo- and heteronuclear NMR experiments. This finding of a bisbenzylisoquinoline alkaloid in Laureliopsis supports its close relationship to Atherosperma and its taxonomic segregation from Laurelia.  相似文献   

12.
In the course of searching for cytotoxic terpenoids from medicinal plants in China, two new eudesmane sesquiterpenoids, 5α-hydroxy-13-methoxy-7αH,11αH-eudesm-4(15)-en-12,8β-lactone (1) and 1β-hydroxy-7αH,11αH-eudesm-4(15)-en-12,8β-lactone (2), along with fourteen known sesquiterpenoids were isolated from the whole plant of Carpesium divaricatum. The structures of new compounds were determined using spectroscopic methods, including IR, HRESIMS, and 1D and 2D NMR spectroscopy. The cytotoxicity of selected sesquiterpene lactones against human oral epidermoid carcinoma (KB), human breast cancer (MCF-7) and human hepatoma (HepG-2) cells was also evaluated by MTT method.  相似文献   

13.
Two new triterpene saponins, paraquinosides A (1) and B (2) were isolated from the aerial parts of Paraquilegia microphylla (Royle) Dromm. et Hutch, a Tibetan ethnic medicine distributed in the Qinghai–Tibet Plateau. On the basis of 1D and 2D NMR evidence, their structure was elucidated as 3-O-α-L-rhamnopyranosyl (1→2)-β-D-glucopyranosyl-15-dehydroxyl-16-O-methyl-24, 25-deoxy-26-hydroxylshengmanol-26-O-β-D-glucopyranoside (1) and 3-O-α-L-Rhamnopyranosyl (1→2)-[β-D-glucopyranosyl(1→3)]-β-D-glucopyranosyl-15-dehydroxyl-16-O-methyl-24, 25-deoxy-26-hydroxylshengmanol-26-O-β-D- glucopyranoside (2), respectively.  相似文献   

14.
A phytochemical investigation of the whole plants of Ajuga decumbens led to the isolation of three new (1, 2a, and 2b) and three known (3a−3c) neo-clerodane diterpenes. Their structures were elucidated by spectroscopic data analysis (IR, ESIMS, HR-ESIMS, 1D and 2D NMR), and the structure of 1 was confirmed by X-ray crystallography. The inhibitory activities on LPS-induced NO production of the six diterpenes were evaluated and compounds 2a, 2b, and 3a showed inhibitory effects.  相似文献   

15.
One new glycoside derivative from syringic acid and one new phenol glycoside, curculigoside E (1) and orchioside D (2), were isolated and characterized from the rootstock of Curculigo orchioides collected in the Nawalparasi District (Nepal). The structures of the new isolated compounds were elucidated by means of spectroscopic methods such as 1D, 2D NMR and MS.  相似文献   

16.
测定了椽竹竹材的理化性质,并与毛竹、青皮竹和绿竹竹材进行了比较分析.结果表明:椽竹各竹龄竹材的基本密度、气干密度和全干密度平均值分别为0.523~0.632 g·cm-3、0.656~0.801 g·cm-3和0.658~0.777 g·cm-3,随着竹龄增长各部位竹材密度表现出增大的趋势,3年生以上椽竹竹材基本密度小于参比竹种毛竹和青皮竹,大于绿竹.3年生以上椽竹竹材的平均气干体积于缩率和全干体积干缩率分别为9.6%和13.6%,大于毛竹;各竹龄椽竹竹材径向干缩率大于弦向干缩率和纵向干缩率.3年生以上椽竹竹材的灰分平均含量小于绿竹和青皮竹,酸不溶木素平均含量与青皮竹接近而小于绿竹,综纤维素含量大于80%,多戊糖、热水抽出物、1%NaOH抽出物平均含量均高于青皮竹和绿竹,而苯-醇抽出物平均含量小于青皮竹和绿竹.综合分析,椽竹作为纸浆材具有较高的利用价值.  相似文献   

17.
本研究采用流式细胞术,以公鸡(Gallus domesticus)血红细胞DNA含量为标准,测定了我国南方几种重要松毛虫的基因组大小(或称C-值)。结果显示,马尾松毛虫(Dendrolimus punctatus)的基因组大小为563.36±7.26 Mb,其雌、雄2C DNA含量分别为1.175 6±0.016 4和1.128 6±0.013 4 pg;思茅松毛虫(Dendrolimus kikuchii)的基因组大小为719.30±9.70 Mb,其雌、雄2C DNA含量分别为1.449 2±0.021 2和1.442 8±0.018 4 pg;云南松毛虫(Dendrolimus houi)的基因组大小为586.82±8.94 Mb,其雌、雄2C DNA含量分别为1.244±0.018 2和1.156±0.018 4 pg。统计分析结果发现,思茅松毛虫基因组显著大于云南松毛虫和马尾松毛虫基因组,后两者的基因组也存在显著差异,但绝对值相差较小。3种松毛虫雌雄虫的基因组大小之间也存在显著的差异,雌虫基因组大于雄虫。几种松毛虫基因组大小的测定,为进一步比较其分子差异、构建基因组文库和基因组学研究奠定了基础。  相似文献   

18.
Phytochemical investigation of the methanol extract of Tinospora cordifolia aerial parts led to the isolation of four new and seven known compounds. The structures of two new aporphine alkaloids, N-formylasimilobine 2-O-β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranoside (tinoscorside A, 1) and N-acetylasimilobine 2-O-β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranoside (tinoscorside B, 2), a new clerodane diterpene, tinoscorside C (3), and a new phenylpropanoid, sinapyl 4-O-β-d-apiofuranosyl-(1 → 6)-O-β-d-glucopyranoside (tinoscorside D, 6) were determined by extensive spectroscopic methods including FTICR-MS and 1D and 2D NMR.  相似文献   

19.
Xu X  Xie H  Xu L  Wei X 《Fitoterapia》2011,82(3):485-488
3,12-Dihydroxy-cis-3,4-methylenedodecanoic acid 3-O-β-d-glucopyranoside, trivially named litchioside C (1), the first cyclopropyl-containing fatty acid glycoside, was isolated along with three previously uncharacterized galactosylacylglycerols from the seeds of Litchi chinensis. Its structure was established on the basis of spectroscopic analysis including HRESIMS and 2D NMR spectra. Its antioxidant and antibacterial activities were evaluated and its biogenetic pathway was discussed.  相似文献   

20.
One new compound, 4-hydroxy-4a,7-dimethoxy-4,4a-dihydrodibenzo-p-dioxin-2(3H)-one (1), was isolated from the aerial parts of the hybrid Hypericum xHidcote’, together with 8 known compounds: caryophyllene-4,5-epoxide, quercetin, quercitrin, quercetin-3-O-β-D-galactopyranoside, epicatechin, betulinic acid methyl ester, β-sitosterol and β-sitosterol glucoside. The structure of the new compound, as well as its absolute configuration, was established by means of spectroscopic data analyses, including 2D NMR spectroscopy and X-ray structural analysis.  相似文献   

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