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1.
Two new cucurbitane-type triterpene glycosides, charantagenins D (1) and E (2), and one new sterol, 7-oxo-stigmasta-5,25-diene-3-O-β-d-glucopyranoside (3), were isolated from the fruit of Momordica charantia L. together with another eight known compounds. Their structures were determined on the basis of spectral analysis. Cytotoxicity activities of the isolated major compounds were evaluated against lung cancer cell line A549, glioblastoma cell line U87, and hepatoma carcinoma cell line Hep3B by using a 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) in vitro assay. Results showed compounds 1 and 7 (goyaglycoside d) with an -OMe substituent group in the side chain exhibited significant cytotoxic activities against cancer cells. Impressively, the IC(50) values of the new compound 1 to A549, U87, and Hep3B were 1.07, 1.08, and 14.01 μmol/L, respectively, which were much lower than those of other tested compounds.  相似文献   

2.
Analysis of Concord grape juice by HPLC with ESI-MS(n), PDA, and fluorescence detection resulted in the identification and quantification of 60 flavonoids and related phenolic compounds, which were present at an overall concentration of 1508 ± 31 μmol/L. A total of 25 anthocyanins were detected, which were mono- and di-O-glucosides, O-acetylglucosides, O-p-coumaroyl-O-diglucosides, and O-p-coumaroylglucosides of delphinidin, cyanidin, petunidin, peonidin, and malvidin. The anthocyanins represented 46% of the total phenolic content of the juice (680 μmol/L). Tartaric esters of hydroxycinnamic acids, namely, trans-caftaric and trans-coutaric acids, and to a lesser extent trans-fertaric acid accounted for 29% of the phenolic content, with a total concentration of 444 μmol/L, of which 85% comprised trans-caftaric acid. Free hydroxycinnamic acids were also quantified but contributed to <1% of the total phenolic content (8.4 μmol/L). The other groups of polyphenolic compounds present in the juice, accounting for 24% of the total, comprised monomeric and oligomeric units of (epi)catechin and (epi)gallocatechin (248 μmol/L), flavonols (76 μmol/L), gallic acid (51 μmol/L), and trans-resveratrol (1.5 μmol/L). The bioavailability of the (poly)phenolic compounds in 350 mL of juice was investigated following acute intake by healthy volunteers. Plasma and urine were collected over 0-24 h and analyzed for parent compounds and metabolites. In total, 41 compounds, principally metabolites, were identified.  相似文献   

3.
磷水平对不同基因型玉米苗期磷吸收利用的影响   总被引:5,自引:1,他引:5  
以齐319(对照)和来源于齐319的耐低磷突变体99037和99106为材料,在1mol/L和1000mol/L.KH2PO4两个磷水平下,通过水培实验研究了磷水平对不同基因型玉米磷吸收、利用和酸性磷酸酶活性的影响。结果表明,低磷条件下三个自交系的根冠比均显著增加,植株磷含量明显降低,生物量显著减小,磷利用效率和酸性磷酸酶活性大大提高。但不同基因型间存在显著差异,自交系99037与齐319相比具有植株磷浓度低、磷素再利用能力强、磷利用效率和净吸收量高等特征,是自交系99037磷高效的可能机理。  相似文献   

4.
Triterpenic acids are widespread in plants and have multiplicity of biological properties. Unfortunately the method for accurate analysis of these compounds remains poorly investigated. This study proposed a highly sensitive and selective precolumn derivatization method for accurate determination of five triterpenic acids (betulinic acid, betulonic acid, maslinic acid, ursolic acid and oleanolic acid) in fruits using acridone-9-ethyl-p-toluenesulfonate (AETS) as fluorescent labeling reagent by HPLC with fluorescence detection (FLD). Response surface methodology was employed to optimize the derivatization reaction, ensuring the sufficient labeling of the analyzed components. The rapid separation of five triterpenic acids could be achieved in as little as 16 min. This developed method offered the exciting detection limits of 1.68-2.04 ng/mL. When applied to several popular fruits in China, it revealed satisfactory applicability and reproducibility. This developed method also exhibits powerful potential for accurate detection of triterpenic acids from other foodstuffs and nature products.  相似文献   

5.
The neuroprotective effects of s-allyl cysteine, s-ethyl cysteine, and s-propyl cysteine in D-galactose (DG)-treated mice were examined. DG treatment increased the formation of Aβ(1-40) and Aβ(1-42), enhanced mRNA expression of β-amyloid precursor protein (APP) and β-site APP cleavage enzyme 1 (BACE1), and reduced neprilysin expression in brain (P < 0.05); however, the intake of three test compounds significantly decreased the production of Aβ(1-40) and Aβ(1-42) and suppressed the expression of APP and BACE1 (P < 0.05). DG treatments declined brain protein kinase C (PKC) activity and mRNA expression (P < 0.05). Intake of test compounds significantly retained PKC activity, and the expression of PKC-α and PKC-γ (P < 0.05). DG treatments elevated brain activity and mRNA expression of aldose reductase (AR) and sorbitol dehydrogenase as well as increased brain levels of carboxymethyllysine (CML), pentosidine, sorbitol, and fructose (P < 0.05). Test compounds significantly lowered AR activity, AR expression, and CML and pentosidine levels (P < 0.05). DG treatments also significantly increased the formation of reactive oxygen species (ROS) and protein carbonyl and decreased the activity of glutathione peroxidase (GPX), superoxide dismutase (SOD), and catalase (P < 0.05); however, the intake of test compounds in DG-treated mice significantly decreased ROS and protein carbonyl levels and restored brain GPX, SOD, and catalase activities (P < 0.05). These findings support that these compounds via their anti-Aβ, antiglycative, and antioxidative effects were potent agents against the progression of neurodegenerative disorders such as Alzheimer's disease.  相似文献   

6.
本研究分3个实验。实验1对比了不同浓度的离子霉素对牛去透明带卵母细胞孤雌激活的效果;实验2比较了手工半卵切割法去核与显微半卵切割法去核的效果;实验3对聚乙二醇(PEG)细胞融合技术在牛手工体细胞克隆的应用进行了初步探讨。结果表明,对于去透明带牛卵母细胞孤雌激活,离子霉素浓度为2.0μmol/L组的激活效果最好,其囊胚发育率(29.4%)极显著地高于浓度为5.0μmol/L的对照组和0.5μmol/L组(囊胚率分别为8.3%和9.4%,P〈0.01);采用半卵切割法去核,手工切割的半卵存活率(85.6%)与显微操作(90.3%)差异不大,切割速率(约100枚卵/h)相仿。对双半卵与体细胞进行同步融合处理时,应用50%浓度的PEG融合率(39.3%)极显著好于45%、55%和60%的PEG(融合率分别为0%、16.2%和5.3%,P〈0.01)。  相似文献   

7.
The influence of two Spanish growing locations with well-differentiated climatic conditions (northern and eastern areas) on the main bioactive compounds, glucosinolates (GLS), total phenolic compounds (TPC), and vitamin C, as well as myrosinase activity and antioxidant capacity in five white cabbage ( Brassica oleracea L. var. capitata) cultivars was investigated. Cabbages with the highest concentration of total GLS presented the highest vitamin C level (r = 0.75, P ≤ 0.05) and the lowest antioxidant capacity (r = -0.76, P ≤ 0.05). The cultivars with the highest vitamin C content had the lowest myrosinase activity (r = -0.89, P ≤ 0.05) and antioxidant capacity (r = -0.86, P ≤ 0.05), whereas those with the largest TPC amount showed the highest antioxidant capacity (r = 0.71, P ≤ 0.05). Cabbage cultivars grown in the northern area of Spain with low temperatures and radiation led to higher mean values of myrosinase activity (29.25 U/g dm), TPC (10.0 GAE mg/g dm), and antioxidant capacity (81.6 μmol Trolox/g dm), whereas cultivars grown in the eastern area with high temperature and radiation led to larger mean values of GLS (14.3 μmol/g dm) and vitamin C (5.3 mg/g dm). The results of this investigation provide information regarding the most suitable Spanish growing location to produce white cabbage with an optimized content of health-promoting compounds.  相似文献   

8.
本研究以龙葵为试验材料,采用水培方法分析了补充Fe对龙葵幼苗Zn毒害耐受性的影响。结果表明,补充200μmol.L 1Fe-EDTA提高了龙葵幼苗对Zn毒害的耐受性。400μmol.L 1ZnCl2处理导致龙葵幼苗株高、根长和叶绿素含量显著减少,并引起H2O2的积累。补充Fe后,植株生长状况得到明显改善,SOD、CAT和APX基因的表达和酶的活性显著提高。同时RT-PCR结果显示,补充Fe后,FeSOD2和CAT1基因的表达明显升高。这些结果表明,Zn毒害对龙葵幼苗生长发育的影响很大程度上可能是由于Zn毒害引起的缺Fe导致的;Zn毒害条件下补充Fe可以通过提高FeSOD2和CAT1基因的表达,提高抗氧化酶的活性,降低ROS的水平,降低植株的氧化伤害。本研究为进一步研究植物响应Zn毒害的生理分子机理,以及植物修复技术的实际应用提供了理论基础。  相似文献   

9.
Organic acid concentration in the proteoid rhizosphere of White Lupin in different soil samples (Oxisol-Ap = Ox, Luvisol-Ap and Luvisol-C = LA and LC) was determined in order to study the influence of root-released carboxylates on the mobilization of phosphate, aluminum, and iron in the rhizosphere. In the LC, organic acids were accumulated as Casalts extractable with water. In the proteoid rhizosphere of this soil sample 55 μmol citrate and 8 μmol malate per g soil were found. In the Ox, no water extractable organic acids were present. However, determination of citrate in the solid phase of this soil by Diffuse Reflectance Infrared Fourier Transform Spectroscopy gave concentrations of 88 and 68 μmol citrate per g soil without and with P application, respectively. Displaced soil solution from the proteoid root rhizosphere of the Ox and the LA increased in Fe and Al concentrations from <50 μmol/L (soil from reference pots without plants) to more than 600 μmol Fe+Al/L. The concentration of P was increased by a factor of 2 despite of P uptake by the proteoid roots. The mobilization of Al, Fe, and P is attributed to ligand exchange of phosphate against citrate and to the solubilization of Al and Fe as carboxylate complexes.  相似文献   

10.
控制肉鸡脂肪过多沉积是肉鸡生产中亟待解决的问题。脱氢表雄酮(dehydroepiandrosterone,DHEA)是人体分泌最为丰富的肾上腺类固醇激素,可经由类固醇激素受体介导发挥生理功能,降低机体生脂能力。本研究以鸡胚原代肝细胞为研究对象,选用含DHEA终浓度为0(对照)、0.01、0.1、1.0、10和100μmol/L的培养液孵育肝细胞20min后收集细胞,放射免疫测定法(RIA)检测胞内cAMP水平。结果发现,0.1~100μmol/L DHEA孵育肝细胞均可显著提高胞内cAMP水平(P<0.05),其中0.1μmol/L DHEA效果最为显著(P<0.01)。0.1μmol/L DHEA孵育肝细胞20min或1h后收集细胞,RIA法分别检测胞内腺苷酸环化酶(adenylate cyclase,AC)和磷酸二酯酶(phosphodiesterase,PDE)活性,(γ-32P)ATP掺入法测定cAMP依赖性蛋白激酶A(protein kinase A,PKA)活性,Western blot法测定cAMP反应元件结合蛋白(cAMP-response element binding protein,CREB)磷酸化水平。结果显示,0.1μmol/L DHEA孵育肝细胞20min可显著降低胞内PDE活性(P<0.05),提高PKA活性(P<0.05),但对AC活性无显著性影响(P>0.05)。0.1μmol/L DHEA处理肝细胞1h可显著提高CREB蛋白磷酸化水平(P<0.05),且这种效应可被PKA抑制剂阻断(P>0.05)。本研究结果提示,DHEA调控肉鸡肝脏脂肪代谢,降低脂肪沉积的机制可能与激活胞内cAMP/PKA信号系统,活化转录因子CREB有关。  相似文献   

11.
用BSA-pAPB免疫Balb/c小鼠,用细胞融合技术制备并用间接ELISA和阻断ELISA筛选抗苯巴比妥单克隆抗体(PB mAb)杂交瘤细胞株,体内诱生腹水法生产PB mAb,应用PB mAb研制PB残留竞争ELISA(ciELISA)快速检测试剂盒(PB-Kit),并测定其性能。结果表明,筛选出3株杂交瘤细胞,最好的3F6-C4株的PB mAb间接ELISA效价为1∶6.4×105,亲和常数(Ka)为1.96×1010 L/moL,半数抑制浓度(IC50)为5.7 μg/L,与巴比妥的交叉反应率(CR%)12.4%,与其它化合物无CR;PB-Kit的线性检测范围1.0~81 μg/L,灵敏度0.75 μg/L,检测限1 μg/L;饲料样和猪尿样的平均添加回收率85.8%和91.3%,平均批内和批间变异系数均<15%。PB-Kit具有快速、敏感、特异、简便等特点,适合PB残留快速检测的推广应用。  相似文献   

12.
Maryland-grown soybean lines modified for low lipoxygenase-1 (LOX-1) content and a traditional nonmodified cultivar were analyzed for fatty acid composition, total phenolic content (TPC), isoflavone composition, relative DPPH? scavenging capacity (RDSC), and hydroxyl radical scavenging capacity (HOSC). Soybean lines included black, brown, and yellow soybeans. TPC of all soybean lines ranged from 2.84 to 4.74 mg gallic acid equiv (GAE)/g flour. Total isoflavones were between 2.78 and 8.66 μmol/g flour. RDSC of all lines was between 0.48 and 14.62 μmol Trolox equiv (TE)/g flour, and HOSC ranged from 53.57 to 135.52 μmol TE/g flour. Some modified-LOX genotypes demonstrated antioxidant capacity and/or isoflavone content similar to or higher than those of the nonmodified cultivar (P < 0.05). Black soybeans demonstrated higher TPC and RDSC than most yellow soybean lines, although they did not have higher isoflavone content. The results demonstrate that modification of the LOX trait did not necessarily alter the antioxidant capacity or chemical composition of the experimental soybean lines when compared with a nonmodified cultivar. These soybean lines may be studied further for nutraceutical properties and use in functional foods.  相似文献   

13.
以大鼠前体脂肪细胞原代单层培养为模型,分别以0(对照组)、40(低剂量组)和160 μmol/L(高剂量组)的二十二碳六烯酸(DHA)处理未分化的前体脂肪细胞(培养第1天)和分化的脂肪细胞(分化第1天)。采用流式细胞仪(FCM)检测细胞周期分布;逆转录-聚合酶链反应(RT-PCR)分析环氧合酶-2(COX-2 )mRNA表达情况,探讨DHA对脂肪细胞周期及基因表达的调节作用。结果显示,未分化的前体脂肪细胞经DHA作用48 h,各处理组前体脂肪细胞G1期百分比均呈上升趋势,但与对照无显著性差异;分化的脂肪细胞经DHA作用24 h,40 μmol/L组细胞内COX-2 mRNA的表达量显著下降,而160 μmol/L组则显著增加。以上结果表明,DHA对大鼠前体脂肪周期无明显的调节作用,而对脂肪细胞内COX-2 mRNA的调节具有明显的浓度依赖效应。  相似文献   

14.
为了研究番茄幼苗在缺磷胁迫下根系形态发育与生长素、生长素信号转导途径中的转录因子NAC1,以及调控NAC1 表达的上游miR164之间的关系。试验以5和500 μmol/L磷浓度作为缺磷胁迫和对照,检测了外源生长素NAA(1-naphthalene acetic acid)及生长素抑制剂NPA(N-1-naphthylphthalamic acid)对侧根形成的影响; 同时采用RT-PCR检测了NAC1和miR164在缺磷胁迫下的时序表达。结果表明,缺磷胁迫下侧根大量形成与生长素及其运输密切相关,在侧根迅速形成的24 h内,NAC1的表达在缺磷胁迫下增强; 而其上游的miR164表达降低,从而揭示了缺磷胁迫下侧根形成与miR164调节NAC1表达之间的关系。  相似文献   

15.
[目的]明确磷(P)不同供应水平对大豆生理性状的影响及其基因型差异,以及这些性状对单株粒重的影响,为磷肥的合理施用提供理论依据.[方法]水培试验以Hoagland营养液为基础,设置4个磷供应水平处理,分别为0(CK)、100、500和1000μmol/L.供试大豆为6个磷高效基因型和6个磷低效基因型.在大豆生长的始花期...  相似文献   

16.
We investigated the varying concentrations of bound amino acids in humic acids (HA) extracted from soils under both crop rotation and continuous cropping of rye. The experiment was created in 1957. Since then, winter rye had been grown continuously and also the sequence of the 7 yr rotation had been started: potato, spring barley, alfalfa, alfalfa, oil seed rape, winter rye, and winter rye. Soils were fertilized with NPK and manure. Continuous cropping of rye increased total acidity of soils and the contents of carboxylic and phenolic groups in HA. The total amounts of the bound amino acids in HA from soils under crop rotation were higher than from continuous cropping of rye. Fertilization with NPK increased the contents of bound amino acids more than manure. Neutral amino acids dominated in all samples of HA, and basic amino acids had the lowest concentrations. In both types of cultivation, glutamic acids, glycine, alanine, valine, and lysine dominated. The proline contents in HA from continuous rye cropping were higher than in HA from soils under crop rotation. The concentrations of β‐alanine and lysine were higher in HA from crop rotation indicating a higher microbial biomass since these compounds are typical constituents of bacteria cell walls.  相似文献   

17.
用磺胺甲噁唑人工免疫原(BSA-SMZ)免疫BALB/C小鼠(Mus muscalus),细胞融合技术筛选抗磺胺甲噁唑单克隆抗体(SMZmAb)杂交瘤细胞,体内诱生腹水法制备SMZ mAb,并鉴定其免疫学特性;应用SMZmAb研制SMZ残留快速检测金标试纸(SMZ-strip),并测定其性能。结果表明,筛选出3株杂交瘤细胞,其中最好的3G6株间接ELISA效价细胞培养上清为1∶8.1×102,腹水为1∶6.4×105,亲和常数(Ka)为3.07×109 L/mol,对SMZ的半数抑制浓度(IC50)为12.4 μg/L,与磺胺嘧啶的交叉反应率(CR%)为2.84%,与其它磺胺类药物无交叉反应;SMZ-strip目测检测限为6 μg/L;其敏感性与竞争ELISA试剂盒相当,符合率为100%;SMZ-strip具有快速、敏感、特异、简便等特点,适合于SMZ残留快速检测的推广应用。  相似文献   

18.
铝胁迫对不同耐铝小麦品种根伸长生长影响的研究   总被引:3,自引:0,他引:3  
为探讨铝胁迫抑制根生长的机理,以耐铝型小麦品种ET8和铝敏感型ES8为试验材料,研究了铝胁迫对小麦根相对伸长率,根尖细胞显微结构的影响以及细胞壁木质素含量及苯丙氨酸解氨酶(PAL)、肉桂醇脱氢酶(CAD)、过氧化物酶(POD)活性的变化。结果表明,ET8和ES8经50μmol/L铝胁迫6、122、4 h后,根相对伸长率随铝胁迫时间延长而变小。利用植物显微技术发现,ET8和ES8经50μmol/L胁迫24 h后,根尖伸长区皮层细胞变扁平,细胞间隙变小,细胞壁褶皱,并呈齿轮状交合;ES8细胞受伤害程度较ET8显著。经50μmol/L铝胁迫6、12、24 h后,ET8和ES8根尖细胞长度受铝胁迫的程度随时间延长而加强,根尖细胞相对长度与根相对伸长率呈显著正相关的关系(r=0.9911**)。50μmol/L铝胁迫24 h后,ET8和ES8根尖苯丙氨酸解氨酶(PAL)、肉桂醇脱氢酶(CAD)、过氧化物酶(POD)活性及细胞壁木质素合成显著增加。上述结果表明,铝胁迫通过增加苯丙氨酸解氨酶、肉桂醇脱氢酶、过氧化物酶活性,促进根尖细胞壁木质素合成,加快细胞的木质化,细胞壁延展性变小,从而抑制细胞的伸长,减小根的生长。由于铝胁迫下ES8中木质素合成显著高于ET8,且根尖细胞结构受破坏较ET8显著,造成铝胁迫下ES8根生长受抑制比ET8显著,是ET8较ES8耐铝胁迫的主要原因。  相似文献   

19.
The stem borer Sesamia nonagrioides (Lefèbvre) is the most important insect pest that attacks maize, Zea mays L., in northwestern Spain. Host plant resistance to this borer was investigated in relation to the cell wall phenylpropanoids content in the pith. Eight inbred lines that differ in resistance were analyzed. Three major simple phenolic acids, p-coumaric, trans-ferulic, and cis-ferulic acids, and three isomers of diferulic acid, 8-5', 8-O-4', and 8-5'b (benzofuran form), were identified. The amount of all these compounds was correlated with the resistance level in the genotypes, with the resistant inbreds having the highest concentrations. The role of these compounds in cell wall fortification and lignification is well-documented, suggesting their possible intervention in S. nonagrioides resistance. Future studies that focus on these compounds could be useful to enhance S. nonagroides resistance.  相似文献   

20.
This study investigates the antioxidant activity and cytotoxicity of Glossogyne tenuifolia extract on various cancer cell lines. The 5.8s DNA of G. tenuifolia was isolated, and the species of this plant was confirmed by NCBI's DNA database. G. tenuifolia was then extracted with ethanol and separated into several fractions using the partition procedure with water, n-butanol, and ethyl acetate (EA). Among these, the EA fraction most significantly affected the activity of DPPH(*) and superoxide anion scavenging. Additionally, only the EA fraction exhibited cytotoxicity on breast cancer cells (MCF-7 and MDA-MB-231) and liver cancer cells (Hep G2 and Hep 3B). Next, the EA fraction was further separated by column chromatography, and 15 fractions were obtained. Three effective components were isolated and identified separately from the active fractions: oleanolic acid (OA) from fraction 6, luteolin from fractions 8-10, and luteolin-7-glucoside from fraction 12. The test of these three compounds on scavenging activity of DPPH(*) and superoxide anion indicates that luteolin had the highest antioxidant activity, whereas the effect of OA was negligible. Additionally, a synergistic effect between luteolin and luteolin-7-glucoside was observed. Kick-out experiments showed that the activities were vanished or decreased. Especially on MDA-MB-231 and MCF-7 cells, the cytotoxicity completely disappeared when luteolin was eliminated from fractions 8-10. These findings demonstrate that luteolin plays a crucial role in the inhibition of the growth of hepatoma cancer cell lines. Fraction 3, which did not contain luteolin, luteolin-7-glucoside, and oleanolic acid, had cytotoxicity on MDA-MB-231, MCF-7, Hep G2, Hep 3B, and A549, which implies that this fraction contained some other effective ingredients and requires further study. The investigation is currently underway in our laboratory.  相似文献   

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