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1.
Three new triterpenoids, 3beta-acetoxy-27-[(E)-cinnamoyloxy]lup-20(29)-en-28-oic acid methyl ester (1), 3beta-acetoxy-27-[(4-hydroxybenzoyl)oxy]lup-20(29)-en-28-oic acid (2), and 3beta-acetoxy-27-[(4-hydroxybenzoyl)oxy]olean-12-en-28-oic acid methyl ester (3), together with nine known triterpenoids, 4-12, were isolated from the root bark of Helicteres angustifolia. The structures of these compounds were established on the basis of spectroscopic methods including 2D-NMR experiments. All twelve compounds were tested for their cytotoxic activities against human colorectal cancer (COLO 205), human hepatoma (Hep G2), and human gastric cancer (AGS) cell lines in vitro. Among them, compounds 2, 3, 3beta-O-[(E)-coumaroyl]betulinic acid (6), and pyracrenic acid (7) showed significant cytotoxic activities against human cancer cells COLO 205 and AGS.  相似文献   

2.
A decoction prepared from the aerial parts of Melampodium divaricatum showed antinociceptive and antihyperalgesic responses when tested in the formalin model in mice. From the CH2Cl2 fraction of the decoction, two non-previously reported secondary metabolites, 3-O-β-D-glucopyranosyl-16α-hydroxy-ent-kaurane ( 1 ) and melampodiamide ( 2 ) [(2′R*,4′Z)-2′-hydroxy-N-[(2S*,3S*,4R*)-1,3,4-trihydroxyoctadec-2-yl]tetracos-4-enamide] were separated and characterized by spectroscopic, spectrometric, and computational techniques. The flavonoids isoquercitrin and hyperoside, which possessed noted antinociceptive properties, were obtained from the active AcOEt fraction of the decoction. The chemical composition of the essential oil of the plant was also analyzed by gas chromatography-mass spectrometry. The major constituents were (E)-caryophyllene, germacrene D, β-elemene, δ-elemene, γ-patchoulene, and 7-epi-α-selinene. Headspace solid-phase microextraction analysis detected (E)-caryophyllene as the main volatile compound of the plant.  相似文献   

3.
目的:探讨马齿苋水提物对溃疡性结肠炎(Ulcerative colitis,UC)的保护作用。方法:利用葡聚糖硫酸钠(Dextran sulfate sodium,DSS)诱导C57BL/6复制UC模型,将小鼠随机分为6组,分别为正常组,DSS模型组,SASP对照组,马齿苋低、中、高剂量组(100,200 mg/kg和400 mg/kg),每天ig给药1次,记录小鼠体重并统计疾病活动指数(Disease activity index,DAI)评分,连续7天。于第8天,测定结肠长度,测定MDA、SOD以及NO含量,观察结肠病理学形态变化,并测定IL-6,IL-1β与TNF-αm RNA的表达。结果:模型组与正常组比较,小鼠体重,结肠长度及SOD有显著降低(P0.05),而DAI评分,MDA、NO含量以及TNF-α,IL-6与IL-1βm RNA的表达有明显升高(P0.05)。而马齿苋水提物中、高组与模型组比较,小鼠的体重,结肠长度以及SOD含量均有显著性提高(P0.05),结肠组织病理损伤有所改善,DAI评分MDA、NO含量以及TNF-α,IL-6与IL-1βm RNA的表达均有明显降低(P0.05)。结论:马齿苋水提物对UC具有保护作用,可能与改变SOD、NO与MDA而抑制氧化应激反应及下调TNF-α,IL-6与IL-1β等细胞因子m RNA的表达而降低炎症反应有关。  相似文献   

4.
Invertase activity has been determined at intervals along primaryroots of Vicia faba as they elongated from 0·5 to 8 cm.Little activity was evident in 0·5–1·0 cmlong primaries but in those 2–8 cm in length the mainpeak of enzyme activity was associated with the region of cellelongation. Changes took place in the pattern of invertase activityalong the primary roots as they lengthened and these changeshave been correlated with fluctuations in both the rate of rootelongation and the supply of sucrose to the root from the cotyledons.The presence of a root cap did not increase the activity ofthis enzyme in the apical 1 mm of these roots. Invertase activity was higher in lateral root primordia thanin most parts of the primary root basal to the meristem, presumablybecause of the presence of sucrose in the adjacent cavity inthe cortex of the primary root. The peaks of invertase activityfound basal to the region of cell elongation in 3–8 cmlong primary roots probably resulted from the development ofroot pnmordia in these parts of the root.  相似文献   

5.
Cancer is currently one of the foremost health challenges and a leading cause of death worldwide. Cervical cancer is caused by cofactors, including oral contraceptive use, smoking, multiparity, and HIV infection. One of the major and considerable etiologies is the persistent infection of the oncogenic human papilloma virus. G. applanatum is a valuable medicinal mushroom that has been widely used as a folk medicine for the treatment and prevention of various diseases. In this study, we obtained crude extract from G. applanatum mushroom with a subcritical water extraction method; cell viability assay was carried out and the crude extract showed an antiproliferative effect in HeLa cells with IC50 of 1.55 ± 0.01 mg/mL; however, it did not show any sign of toxicity in HaCaT. Protein expression was detected by Western blot, stability of IκBα and downregulation of NFκB, IKKα, IKKβ, p-NFκB-65(Ser 536) and p-IKKα/β(Ser 176/180), suggesting loss of survival in a dose-dependent manner. RT-qPCR revealed RNA/mRNA expression; fold changes of gene expression in Apaf-1, caspase-3, cytochrome-c, caspase-9, Bax and Bak were increased, which implies apoptosis, and NFκB was decreased in a dose-dependent manner. DNA fragmentation was seen in the treatment groups as compared to the control group using gel electrophoresis. Identification and quantification of compounds were carried out by GC–MS and HPLC, respectively; 2(5H)furanone with IC50 of 1.99 ± 0.01 μg/mL could be the responsible anticancer compound. In conclusion, these findings suggest the potential use of the crude extract of G. applanatum as a natural source with anticancer activity against cervical cancer.  相似文献   

6.
Artemisia annua L. is a Chinese medicinal herb, but the origin of its pharmacological properties, including its anti-inflammatory activity, remain unknown. In this study, five new monoterpene glycosides ( 1 – 5 ) and two new sesquiterpene glycosides ( 6 and 7 ) were isolated from the aqueous extract of the aerial parts of A. annua. The structures of these glycosides were determined using high-resolution electrospray ionization mass spectrometry, nuclear magnetic resonance spectroscopy, electronic circular dichroism calculations, and chemical hydrolysis methods. The anti-inflammatory activities of the isolated compounds were evaluated by down-regulating interleukin-6 (IL-6) in lipopolysaccharide-stimulated RAW 264.7 macrophages. Notably, all the new compounds significantly inhibited the expression of IL-6 in a dose-dependent manner.  相似文献   

7.
西藏芫根提取物对小鼠抗缺氧作用的初步研究   总被引:1,自引:0,他引:1  
实验研究西藏芫根提取物的抗缺氧活性.通过建立小鼠常压缺氧模型、急性脑缺血性缺氧模型以及亚硝酸钠中毒模型,以蒸馏水作为空白对照,盐酸普萘洛尔作为阳性对照,观察芫根水、65%乙醇及95%乙醇提取物的10 g/kg、15 g/kg和20 g/kg剂量组对小鼠缺氧的保护作用,同时观察各提取物10 g/kg剂量组对红细胞数量和血红蛋白含量的影响.结果表明,芫根水提取物、65%乙醇提取物及95%乙醇提取物均能明显延长模型小鼠在常压缺氧、急性脑缺血性缺氧及亚硝酸钠中毒时的存活时间,并可增加外周血象中红细胞数与血红蛋白含量,显示芫根提取物具有抗缺氧活性.  相似文献   

8.
9.
The metabolic fates of the carbon skeletons of leucine, lysine, and threonine were studied in growing rats on the diets containing graded levels of protein calorie percentages (10, 20, 30, and 40PC%) by use of either gluten or zein at 4100 kcal of metabolizable energy per kg of diets. In growth experiment for 21 days, body weight gain, food intake, and body fat increased at higher PC% in the gluten diets, but rats given zein did not maintain their initial weight even at 40PC%. The concentration of plasma free lysine remained low with the zein diets, but plasma threonine increased at 10 and 20PC% in the gluten and zein diets, respectively. Plasma leucine increased as the protein level increased either dietary protein. More than 70% of 14C was incorporated into body protein 12 h after an intraperitoneal injection of labeled lysine in all groups, but little 14CO2 was expired in rats on the gluten and zein diets. About 79% of 14C-threonine was incorporated into body protein in rats given the gluten and zein diets at 10PC%, but the values were gradually decreased with increasing the dietary protein levels. Some 40–50% of 14C-leucine was incorporated into the body protein in rats given the gluten diets, and the values for the zein diets were extensively decreased in the higher PC% groups where the expired 14CO2 was inversely increased to a great extent. These results showed that, when a specific amino acid was limiting or deficient in the diet, the major portion of the labeled amino acid was utilized for body protein synthesis and little was oxidized to carbon dioxide, whereas the oxidative degradation of essential amino acid other than limiting one was increased and the efficiency of the amino acid utilization was relatively decreased.  相似文献   

10.
Abstract: The high performance liquid chromatography (HPLC) technique was applied to measure phenylalanine ammonia-lyase (PAL, EC 4.3.1.5) activity in soybean ( Glycine max L. Merril cv. BR16) roots. t -Cinnamate, the catalytic product of the PAL reaction was quantified at 275nm by isocratic elution with methanol: water through an ODS(M) column. Comparative experiments were carried out with 1.0 mM ferulic acid, an inducer of PAL activity. The results suggest that liquid chromatography is a rapid and sensitive method to analyze PAL activity in non-purified extract.  相似文献   

11.
探究了青花椒水提物及精油对松材线虫的防治作用。分别提取青花椒水提物及精油,倍比稀释法探究其对松材线虫寿命及运动行为的影响。实验结果表明2.5 mg/mL的青花椒水提物和0.1%的青花椒精油4小时均能完全杀灭松材线虫,青花椒水提物和精油均能降低松材线虫的运动行为能力,从而说明青花椒水提物及精油对松材线虫具有防治作用。  相似文献   

12.
Exogenous DNA has been administered to roots of Vicia faba inwhich this DNA stimulates an increase in acid deoxyribonucleaseactivity. This enzyme activity is associated with vesicles whichfollow whatappears to be the cytological pathway of foreignDNA in host tissues.  相似文献   

13.
The initiation and subsequent emergence of lateral roots fromthe tissues of the primary has been examined in attached andexcised roots of Pisum. Lateral anlage inception took placein cultured roots which were 1 and 4 cm in length at the timeof excision. However, whereas a few primordia completed theirdevelopment and grew out as emerged laterals from those excisedroots which were 4 cm long, at the onset of culturc none appearedon those which had an initial length of 1 cm. The changes which took place in the rate of cell proliferationin the apical millimetre of each batch of cultured roots withtime following excision, were followed and related to the appearanceor otherwise of secondary roots on the cultured primaries. Pisum sativum L., garden pea, anlage, primodium, emerged lateral, apical meristem, cell proliferation  相似文献   

14.
The volumes of tissues in leaves of two species ofTypha with different habitus were measured. It was found that air cavities occupy more than 50%, parenchyma about 20% and photosynthetic tissue about 10% of the total volume of the leaf. If the cavities are omitted, parenehyma amounts to approximately 50% and photosynthetic tissue to little more than 20% of the total volume of tissues. The relative volumes of tissues vary continuously from the base to the tip of the leaf. The differences between the two species studied were not large. Besides the relative volumes, the real ones of leaves and tissues were calculated.  相似文献   

15.
DNA recombinases (RecA in bacteria, Rad51 in eukarya and RadA in archaea) catalyse strand exchange between homologous DNA molecules, the central reaction of homologous recombination, and are among the most conserved DNA repair proteins known. RecA is the sole protein responsible for this reaction in bacteria, whereas there are several Rad51 paralogs that cooperate to catalyse strand exchange in eukaryotes. All archaea have at least one (and as many as four) RadA paralog, but their function remains unclear. Herein, we show that the three RadA paralogs encoded by the Sulfolobus solfataricus genome are expressed under normal growth conditions and are not UV inducible. We demonstrate that one of these proteins, Sso2452, which is representative of the large archaeal RadC subfamily of archaeal RadA paralogs, functions as an ATPase that binds tightly to single-stranded DNA. However, Sso2452 is not an active recombinase in vitro and inhibits D-loop formation by RadA. We present the high-resolution crystal structure of Sso2452, which reveals key structural differences from the canonical RecA family recombinases that may explain its functional properties. The possible roles of the archaeal RadA paralogs in vivo are discussed.  相似文献   

16.
17.
亚麻根化学成分的研究   总被引:4,自引:0,他引:4  
采用硅胶柱色谱法从亚麻根中分得5个化合物,通过波谱分析和甲醇酸水解鉴定了它们的结构,分别为Linum cerebrosideA(1),1-O-β-D-glueopyranosyl-(2S,3R,4E,8Z)-2[(2(R)-hydroxyhexadecanoyl)amido]-4,8-octadecadiene-1,3-diol(2),胡萝卜苷(4),花生酸(5)和ent-kaurane-3-oxo-16α-17-diol(6)。其中化合物1为新化合物,化合物2、5、6均为首次从该植物中分离鉴定。  相似文献   

18.
《Aquatic Botany》1987,28(2):129-141
In Najas marina L., total alcohol dehydrogenase (ADH) activity is very high in seeds. The pattern is very complex. In mature tissue, the activity is much lower and only one zone of activity is detected. From molecular weight comparisons, densitometric scans and dissociation-reassociation experiments, we could conclude that the major ADH system is controlled by two genes, Adh 1 and Adh 2. The gene product shows interactions and forms homodimers, heterodimers and intergenic heterodimers. Some polymorphism was found within populations of N. marina subsp. marina. In N. marina subsp. intermedia (Gorski) Casper, many different types of zymograms could be detected. Three additional allelic forms were found for Adh 1 and two for Adh 2. In pollen, an additional system is induced which forms heterodimers with Adh 1 and is probably under the control of a third gene, Adh 3. The enzymes are nicotinamide-adenine dinucleotide (NAD) specific and oxidise a wide variety of primary alcohols, with preference for short chain lengths.  相似文献   

19.
瑞香狼毒化学成分研究   总被引:1,自引:0,他引:1  
从瑞香狼毒95%乙醇提取物中分离得到了17个化合物,根据理化性质和波谱数据鉴定为4’-甲氧基-7-羟基黄酮(1),山奈酚(2),5,4’-二羟基-7-甲氧基二氢黄酮(3),4’,5,7-三羟基黄烷酮(4),3,5,7-三羟基黄烷酮(5),山奈酚-7-O-β-D-葡萄糖苷(6),α-香树酯醇(7),(24R)-5α-豆甾-7,22(E)-二烯-3α-醇(8),狼毒色原酮(9),伞形花内酯(10),东莨菪素(11),异东莨菪素(12),狼毒素(13),瑞香内酯(14),异茴芹香豆素(15),β-谷甾醇(16),瑞香素乙(17)和β-胡萝卜甙(18)。其中化合物1-8为首次从该植物中分离得到。  相似文献   

20.
沙枣(Elaeagnus angustifolia L.)研究现状与展望   总被引:15,自引:0,他引:15  
沙枣(Elaeagnus angustifolia L.)是胡颓子科胡颓子属的一种小乔木,是一种集生态效益与经济效益于一体的资源植物,是西北地区具有开发利用前景的重要资源.对我国上世纪60年代至今对沙枣的研究文献作一综述,包括沙枣果实、花、叶、果核及树液的成分、木材的理化性质、沙枣的生理生态学特性、引种实验、繁殖方法、品种划分等方面的工作.最后提出了沙枣利用中存在的问题及建议.  相似文献   

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