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1.
黄少甫  徐炳声   《广西植物》1984,(4):281-284
<正> 前言 池杉(Taxodium ascendens Brongn.)别名池柏,是杉科(Cupressaceae)落羽杉属(Taxodium)的高大乔木,生长快,材质好,抗性强,树型美,为良好的用材和造园树种。 池杉原产北美,本世纪初引入我国江苏南京、南通、上海和河南鸡公山等地。三十年代扩种到武汉、江西庐山、广州等地。解放后,池杉的分布区迅速扩大,长江南北各省广泛栽  相似文献   

2.
白豆杉(pseudotaxus chienii)为我国特有植物,属于红豆杉科(Taxaceae)白豆杉属(pseudotaxus)。本文对白豆杉树皮的化学成分以及就该种植物中是否含有紫杉醇(Taxol)进行分析研究。 并从石油醚提取物中已鉴定出2个化合物,为铁杉树脂醇(Tsugalactone)和1.1.3一三苯基丙烷 (1.1.3-triphenylpropane)。  相似文献   

3.
于飞雪  杨银河  赵沛基  陈瑶 《广西植物》2016,36(9):1112-1118
从蛇足石杉内生菌的次级代谢产物中寻找活性成分,为进一步开发利用蛇足石杉药用植物资源提供了新途径,但至今其内生菌代谢产物的系统性研究较为少见。种类丰富的内生真菌普遍存在于各种植物中,但蕨类植物中内生真菌的研究较少。为了寻找蛇足石杉内生菌中的细胞毒活性成分,该研究从蛇足石杉根部分离得到一株球毛壳属(Chaetomium sp.)真菌M336,对其化学成分进行了研究。对蛇足石杉内生真菌M336采用PDA固体培养基扩大发酵,发酵物经提取及乙酸乙酯萃取后,通过正相硅胶柱色谱法、Sephadex LH-20凝胶柱色谱法、薄层制备、高效液相色谱等色谱手段对其发酵物中的化学成分进行分离纯化,利用理化性质、质谱、核磁等波谱分析技术,并结合相关文献数据鉴定化合物的结构。结果表明:从内生真菌M336发酵提取物的乙酸乙酯萃取部分分离并鉴定出8个化合物,分别为chaetoviridines F、chaetoviridines E、5′-epichaetoviridin A、5′-epichaetoviridin A、xanthoquinodins Al、xanthoquinodins A2、xanthoquinodins B1和毛壳菌素。从M336中分离得到8个化合物,化合物3有一定的抑菌作用,其余化合物有一定的细胞毒活性。该研究结果丰富了蛇足石杉内生真菌球毛壳属中的天然细胞毒活性的化合物。  相似文献   

4.
本文研究了樟树叶的化学成分。主要采用硅胶、Sephadex LH-20凝胶和聚酰胺等柱层析方法对樟树叶的化学成分进行分离纯化,并根据理化性质、波谱数据(1H NMR,13C NMR)鉴定化合物的结构。从樟树叶的甲醇提取物中分离鉴定出9个化合物,分别为山柰酚-3-O-β-D-葡萄糖苷(1)、槲皮素-3-O-β-D-鼠李糖苷(2)、槲皮素-3-O-β-D-葡萄糖苷(3)、异鼠李素-3-O-β-D-葡萄糖苷(4)、黑色五味子单体苷(5)、山奈酚-3-O-β-D-芸香糖苷(6)、异鼠李素-3-O-β-D-芸香糖苷(7)、新芝麻脂素(8)和maculatin(9)。化合物1为首次从樟属中分离得到,化合物4、5、8为首次从樟科植物中分离得到。  相似文献   

5.
目的:对人参(Panax ginseng C.A.Mey.)花蕾的化学成分进行研究。方法:采用多种柱色谱技术进行分离纯化,并通过波谱分析方法鉴定化合物的结构。结果:分离鉴定了9个化合物,分别鉴定为咖啡碱(1)、胡萝卜苷(2)、豆甾醇3-O-葡萄糖苷(3)、α-菠甾醇(4)、7-豆甾烯-3β-醇(5)、人参皂苷Rk3(6)、人参皂苷Re(7)、人参皂苷Rg2(8)、谷甾醇(9)结论:其中化合物1为五加科植物中首次分离得到,化合物3、4、5为人参花中首次分离得到。  相似文献   

6.
为研究短角湿生冷水花(Pilea aquarum subsp.brevicornuta)化学成分。实验采用色谱法从中分离得到7个化合物,包括5个五环三萜、一个甾醇和一个木脂素。利用波谱学方法鉴定了它们的结构,分别鉴定为pilearbornol(1)、rubiarbonone D(2)、camarolide(3)、表齐墩果酸(4)、齐墩果酮酸(5)、5,8-epidioxy-(3β,5α,8α,22E)-ergosta-6,9(11),22-trien-3-ol(6)和桉脂素(7)。其中,化合物1和2属于乔木萜烷型(arborane)三萜,化合物1为新化合物,化合物2的绝对构型首次通过X-射线单晶衍射得到了确定。所有化合物均为首次从该植物中分离得到,这也是首次从荨麻科植物中分离得到乔木萜烷型三萜化合物。  相似文献   

7.
本文研究萹蓄Polygonum aviculare L.乙酸乙酯萃取部位的抑菌活性和化学成分。采用打孔法进行抑菌活性实验,采用硅胶柱色谱、Sephadex LH-20凝胶柱色谱等方法进行分离和纯化,并根据理化性质、光谱数据进行结构鉴定。结果萹蓄乙酸乙酯部位对五种试验菌均显示一定的抑菌活性,并从中分离得到10个化合物,分别鉴定为没食子酸甲酯(1)、β-胡萝卜甙(2)、山柰酚(3)、槲皮素(4)、没食子酸(5)、萹蓄苷(6)、槲皮苷(7)、myricetin 3-O-(3'-O-galloyl)-rhamnopyranoside(8)、杨梅树皮苷(9)、胡桃宁(10)。其中化合物1和8为首次从该植物中分离得到,化合物8为首次从蓼科蓼属植物中分离得到。  相似文献   

8.
观赏性珍稀濒危植物红皮糙果茶枝叶化学成分研究   总被引:1,自引:0,他引:1  
在开展中国特有珍稀濒危植物化学成分及其生物功能研究中,我们运用硅胶、MCI和葡聚糖凝胶柱色谱以及半制备HPLC等分离纯化方法,首次对观赏性植物红皮糙果茶(Camellia crapnellia)枝叶中的化学成分进行了研究,得到7个单体化合物。结合理化性质和波谱数据与文献值对照分析鉴定了它们的结构,分别为:(-)-pinoresinol(1)、(±)-syringaresinol(2)、(±)-lariciresinol(3)、cytochalasin D(4)、blumenol B(5)、kaempferol-3-O-Lrahmnoside(6)和α-spinasterol(7)。其中化合物2~5为首次从山茶属植物中分离得到。对分离所得化合物进行了蛋白酪氨酸磷酸酯酶1B(PTP1B)抑制活性测试,结果显示均无明显活性。  相似文献   

9.
中山杉302和墨西哥落羽杉及其回交一代的同工酶分析   总被引:6,自引:0,他引:6  
落羽杉属有落羽杉〔Taxodiumdistichum (L .)Rich .〕、墨西哥落羽杉 (T .mucronatumTenore)和池杉 (T .ascendensBrongn .) 3个种 ,该属是世界重要的园林及用材树种 ,墨西哥落羽杉是其中较耐盐碱的树种 ,它的引种选育历来受到广泛重视。中山杉 30 2 (T .‘Zhongshansha 30 2’)是江苏省·中国科学院植物研究所于 2 0世纪 80年代从落羽杉×墨西哥落羽杉杂交后代中选育出来的优良品种 ,具有生长快和耐盐碱等特性[1 ] 。本实验从中山杉 30 2×墨西哥落羽杉回交一代中选…  相似文献   

10.
综合运用硅胶柱色谱、反相硅胶柱色谱和Sephadex LH-20凝胶柱色谱以及制备型高效液相等色谱方法对番荔枝科瓜馥木属植物头序瓜馥木Fissistigma retusum枝叶中的化学成分进行了系统研究,从其枝叶的95%乙醇提取物中分离鉴定了12个化合物,根据化合物的理化性质及其波谱学数据将它们分别鉴定为:原儿茶酸乙酯(1)、(S)-甲氧基-(3,5-二甲氧基-4-羟苯基)乙二醇(2)、2-顺式-4-反式-脱落酸(3)、山萘酚-3-O-а-L-吡喃阿拉伯糖苷(4)、柚皮素(5)、香树素(6)、圣草酚(7)、(2R,3S)-5,7,3'-三甲氧基表儿茶素(8)、5,6,8-三甲氧基-7-羟基二氢黄酮(9)、丁香脂素(10)、epiyangambin(11)、seartemin(12)。其中化合物1和2为2个酚酸类化合物,3和4为2个萜类化合物,5~9为5个黄酮类化合物,化合物10~12为3个木脂素类化合物,化合物1~12为首次从番荔枝科瓜馥木属植物中分离得到。  相似文献   

11.
12.
Three new compounds, butyl homononactate (5), butyl nonactate (6), 8-actyl homononactic acid (7), along with four known compounds homononactic acids (1), nonactic acid (2), homononactyl nonactate (3), homononactyl homononactate (4) were isolated from the marine Streptomyces griseus RSH0407, derived from the plant Salicornia sp., Chenopodiaceae. Their structures were elucidated by extensive spectroscopic techniques and by comparison with data reported in the literature. The absolute configuration of 3 was first reported by using X-ray copper radiation. Compound 5 exhibited cytotoxic activities against the HCT-8, A2780, BGC-823, BEL-7402, and A549 cell lines in vitro, with IC50 values of 2.87 ± 0.20, 4.90 ± 0.30, 2.19 ± 0.32, 5.07 ± 0.23 and 1.78 ± 0.18 μM, respectively, and compounds 47 showed weak antibacterial activities against four bacterials respectively.  相似文献   

13.
Plants respond to wounding by means of a multitude of reactions, with the purpose of stifling herbivore assault. Phospholipase D (PLD) has previously been implicated in the wounding response. Arabidopsis ( Arabidopsis thaliana ) AtPLD α 1 has been proposed to be activated in intact cells, and the phosphatidic acid (PA) it produces to serve as a precursor for jasmonic acid (JA) synthesis and to be required for wounding-induced gene expression. Independently, PLD activity has been reported to have a bearing on wounding-induced MAPK activation. However, which PLD isoforms are activated, where this activity takes place (in the wounded or non-wounded cells) and what exactly the consequences are is a question that has not been comprehensively addressed. Here, we show that PLD activity during the wounding response is restricted to the ruptured cells using 32Pi-labelled phospholipid analyses of Arabidopsis pld knock-out mutants and PLD -silenced tomato cell-suspension cultures. pldα1 knock-out lines have reduced wounding-induced PA production, and the remainder is completely eliminated in a pldα1 / δ double knock-out line. Surprisingly, wounding-induced protein kinase activation, AtLOX2 gene expression and JA biosynthesis were not affected in these knock-out lines. Moreover, larvae of the Cabbage White butterfly ( Pieris rapae ) grew equally well on wild-type and the pld knock-out mutants.  相似文献   

14.
In the mammalian brain, kynurenine aminotransferase II (KAT II) and kynurenine 3-monooxygenase (KMO), key enzymes of the kynurenine pathway (KP) of tryptophan degradation, form the neuroactive metabolites kynurenic acid (KYNA) and 3-hydroxykynurenine (3-HK), respectively. Although physically segregated, both enzymes use the pivotal KP metabolite l -kynurenine as a substrate. We studied the functional consequences of this cellular compartmentalization in vivo using two specific tools, the KAT II inhibitor BFF 122 and the KMO inhibitor UPF 648. The acute effects of selective KAT II or KMO inhibition were studied using a radiotracing method in which the de novo synthesis of KYNA, and of 3-HK and its downstream metabolite quinolinic acid (QUIN), is monitored following an intrastriatal injection of 3H-kynurenine. In naïve rats, intrastriatal BFF 122 decreased newly formed KYNA by 66%, without influencing 3-HK or QUIN production. Conversely, UPF 648 reduced 3-HK synthesis (by 64%) without affecting KYNA formation. Similar, selective effects of KAT II and KMO inhibition were observed when the inhibitors were applied acutely together with the excitotoxin QUIN, which impairs local KP metabolism. Somewhat different effects of KMO (but not KAT II) inhibition were obtained in rats that had received an intrastriatal QUIN injection 7 days earlier. In these neuron-depleted striata, UPF 648 not only decreased both 3-HK and QUIN production (by 77% and 66%, respectively) but also moderately raised KYNA synthesis (by 27%). These results indicate a remarkable functional segregation of the two pathway branches in the brain, boding well for the development of selective KAT II or KMO inhibitors for cognitive enhancement and neuroprotection, respectively.  相似文献   

15.
研究了从硬枝树花中提取得到的4个单体化合物松萝酸(usnic acid)、去甲环萝酸(evernic acid)、巴尔巴地衣酸(barbatic acid)和水杨嗪酸(salazinic acid)对H22荷瘤小鼠的抑瘤作用,并且对抑瘤率、胸腺指数、脾指数及小鼠白介素-2含量等各个指标的进行检测,以说明此4种化合物对小鼠肿瘤生长的抑制效果。结果表明,松萝酸高、中剂量组,去甲环萝酸高、中剂量组,巴尔巴地衣酸低剂量组,水杨嗪酸高剂量组对小鼠肿瘤有较好的抑制效果,与阴性对照组比较有极显著差异(P0.01),并且这些组的H22荷瘤小鼠血清中白介素-2的含量显著增加,与抑制肿瘤活性具有相关性。  相似文献   

16.
A method is presented for the quantitative estimation of the individual amino acid radioactivity in biological samples. The material is deproteinized with cold acetone, and, after acetone evaporation, is passed through a column containing 1 g of Amberlite XAD-2, then eluted with 10% ethanol. The samples are derivatized with Sanger's reagent (alkaline 1-fluoro-2,4-dinitrobenzene) and passed again through the Amberlite XAD-2 column; the 10% ethanol eluate is now discarded and the DNP-amino acids eluted with acetone. Aliquots are used for TLC chromatography on Silicagel plates; the spots are identified, cut away and their radioactivity estimated. The actual recovery of radioactivity in the spots is about 86-92% of the initial radioactivity. No contamination with radioactive glucose, lactate, pyruvate or glycerol has been observed.  相似文献   

17.
Dihydroplipoate and lipoate are physiological thiols which in addition to their coenzyme functions exhibit antioxidant activity. For NMR investigations of their protective mechanism in biological and model systems it is very important to know the full assignment of proton and carbon spectra of these molecules in water (D2O). An unambiguous assignment of proton and carbon NMR spectra has been made for dihydrolipoate and its short chain derivatives bisnor-and tetranor-lipoic acid in D2O and CDCl3 solutions using 2D NMR methods.

Oxidation of dihydrolipoic acid produces substantial electron density deshielding of the carbons nearest to the SH groups with the largest shift found at the inner SH group (17.79 ppm in D2O, 16.93 in CDCl3) and almost no changes in the tail portion of the molecule. However, bisnor-dihydrolipoic acid and especially tetranor-dihydrolipoic acid have more carbon deshielding near the outer SH group of the molecule which correlates with their known diminished ion chelating activity.

Moreover, the proton triplet at position 2 of lipoic acid has strong pH dependence (pK = 4.58) due to the close proximity to the carboxylic group and this feature may be used for monitoring pH.  相似文献   

18.
D-焦谷氨酸的研制   总被引:2,自引:0,他引:2  
研究了D-焦谷氨酸的制备,提纯精制以及分析化验等方面的有关问题。  相似文献   

19.
RadioactiveN-acetylmannosamine was injected intravenously into rats to labelN-acetylneuraminic acid (NeuAc) and CMP-NeuAc. Nuclei were isolated from the livers using a non-aqueous technique to prevent leakage of polar metabolites. A preparation was obtained, which was eight times enriched in nuclei based on the ratio DNA/RNA. Free NeuAc and CMP-NeuAc were isolated from this nuclear fraction and from whole liver, and the specific radioactivities were determined. It appeared that at all time points studied, i.e. 1.5, 9.5, and 18 min after injection, the specific radioactivities of free NeuAc as well as of CMP-NeuAc in the nuclear preparation were lower than those in whole liver. Also no significant differences were found between free NeuAc and CMP-NeuAc in the ratio of specific radioactivities in the nuclear fraction/whole liver. Furthermore, no enzyme involved in the synthesis of NeuAc was enriched in the nuclear preparation as compared to various other cytosolic and non-cytosolic enzymes.Because newly synthesized NeuAc is channelled into a special pool and used for activation to CMP-NeuAc [Ferwerda W, Blok CM, van Rinsum J (1983) Biochem J 216:87–92], these results point to a site of activation of NeuAc to CMP-NeuAc other than the nuclear compartment. This might indicate that the nuclear-localized enzyme, CMP-NeuAc synthase, leaves the nucleus before exerting its action.Abbreviations ManNAc kinase (EC 2.7.1.60) ATP:2-acetamido-2-deoxy-d-mannose 6-phosphotransferase - GlcNAc kinase (EC 2.7.1.59) ATP:2-acetamido-2-deoxy-d-glucose 6-phosphotransferase - NeuAc 9-phosphatase (EC 3.1.3.29) N-acetylneuraminate 9-phosphate phosphohydrolase - CMP-NeuAc synthase (EC 2.7.7.43) CTP:N-acetylneuraminic acid cytidylyltransferase - glucose 6-phosphatase (EC 3.1.3.9) d-glucose 6-phosphate phosphohydrolase - p-nitrophenylphosphatase (EC 3.1.3.1/2) orthophosphoric monoester phosphohydrolase - LDH (EC 1.1.1.27) l-lactate:NAD oxidoreductase - (1-4)-galactsyltransferase (EC 2.4.1.38) -N-acetylglucosaminide (1-4)-galactosyltransferase  相似文献   

20.
The m and p isomers of hydroxyphenylacetic acid have been identified and quantitated in whole rat brain and in several regions using a capillary column high resolution gas chromatography–mass spectrometry procedure. Their concentrations were: for m-hydroxyphenylacetic acid (mean ± S.E., number of determinations in parentheses)—whole brain, 2.3 ± 0.3 ng/g (7); hypothalamus, 1.2 ± 0.3 ng/g (5); caudate nucleus, 5.5 ± 0.6 ng/g (5); brain stem, 1.8 ± 0.1 ngig (5); cerebellum, 1.2 ± 0.1 ng/g (5) and the “rest,” 1.7 ± 0.1 ng/g (5); and for p-hydroxyphenylacetic acid–whole brain, 10.6 ± 0.7 ng/g (7); hypothalamus, 4.5 ± 0.1 ng/g (4); caudate nucleus, 28.3 ±1.6 ng/g (5); brain stem, 8.6 ± 0.6 ng/g (5); cerebellum, 8.1 ± 0.4 ng/g (9, and the “rest,” 5.3 ± 0.5 ng/g (5). This heterogeneous distribution parallels closely that exhibited by their respective precursor amines, m- and p-tyramine.  相似文献   

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