共查询到20条相似文献,搜索用时 10 毫秒
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Yan-Qing Ye Zu-Hong Ma Qiao-Fen Yang Yan-Qi Sun Rui-Qi Zhang Run-Fang Wu 《Natural product research》2019,33(19):2731-2737
A new benzylated alkamide, N-(3,4-dimethoxybenzyl)-9Z-oleamide (1), along with two known ones (2 and 3) were isolated from the roots of Lepidium meyenii collected from Lijiang, Yunnan Province of China. Their structures were elucidated by extensive spectroscopic analyses and the new compound further confirmed by a one-step synthesis. All the isolated alkamides were evaluated for their cytotoxicity against five human cancer cell lines. However, no significant activities were detected at concentrations up to 40?μM. 相似文献
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Ranran Zhang Junhong Liu Hui Yan Xingrong Peng Ling Zhang Minghua Qiu 《Molecules (Basel, Switzerland)》2021,26(16)
Five new thiohydantoin derivatives (1–5) were isolated from the rhizomes of Lepidium meyenii Walp. NMR (1H and 13C NMR, 1H−1H COSY, HSQC, and HMBC), HRESIMS, and ECD were employed for the structure elucidation of new compounds. Significantly, the structure of compound 1 was the first example of thiohydantoins with thioxohexahydroimidazo [1,5-a] pyridine moiety. Additionally, compounds 2 and 3 possess rare disulfide bonds. Except for compound 4, all isolates were assessed for neuroprotective activities in corticosterone (CORT)-stimulated PC12 cell damage. Among them, compound (−)-3 exhibited moderate neuroprotective activity (cell viability: 68.63%, 20 μM) compared to the positive control desipramine (DIM) (cell viability: 88.49%, 10 μM). 相似文献
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基于高速逆流色谱(HSCCC)技术从玛咖中分离制备出两种芥子油苷,苄基芥子油苷(glucotropaeolin, GTL)和甲氧基苄基芥子油苷(glucolimnanthin, GLI)。使用正交设计试验对分离条件进行优化,采用高分辨质谱对制备的组分进行鉴定,采用高效液相色谱法(HPLC)对组分进行定量分析。确定了两个组分GTL与GLI的HSCCC最佳分离条件:溶剂系统为正丁醇-乙腈-200 g/L硫酸铵溶液(1:0.5:2.4, v/v/v),上相为固定相,下相为流动相,流动相流速2 mL/min,主机转速900 r/min,从玛咖根粗提物中一次性分离得到157.72 mg/kg纯度为97.9%的苄基芥子油苷和31.93 mg/kg的甲氧基苄基芥子油苷,固定相保留率达57.6%。该方法成本低,简便易行,样品损失量小,可大量循环进样制备。 相似文献
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《Journal of carbohydrate chemistry》2012,31(9):552-565
AbstractJuniperus tibetica Kom., a common forest species in Tibet, has been traditionally used in Tibetan medicine to treat rheumatic arthritis. In order to investigate the effective substances of J. tibetuca, anticomplent assay-guided fractionation using gradient anion-exchange chromatography and gel permeation chromatography was applied to the crude polysaccharides of the twigs and leaves of J. tibetica and led to the isolation of a homogenous polysaccharide, YB-PS. It exhibited a robust anticomplement activity (CH50: 461?±?10?μg/mL) through the classical pathway of complement system activation by targeting complement components C1q, C3, C4 and C5. The structure of YB-PS was studied by monosaccharide composition and methylation analyses, 1?D, 2?D NMR data and scanning electron microscope. The results indicated that YB-PS was composed of Ara, Gal, and Glc with a molar ratio of 5.8:3.0:1.2. Its backbone was comprised of 1,3-linked α-Araf, 1,3,5-linked α-Araf, 1,2,4-linked α-Galp, and 1,3-linked α-Glcp with terminal α-Araf, β-Galp and 1,4-linked β-Galp as branches. YB-PS was found to have a sheet structure with smooth surface. This study provided scientific foundation for YB-PS as a potential complement inhibitor to treat diseases involved with excessive activation of the complement system. 相似文献
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电喷雾质谱结合化学计量学方法快速筛选玛咖促睾丸间质细胞增殖活性成分 总被引:2,自引:0,他引:2
应用电喷雾串联质谱法( ESI-MS/MS)对云南和秘鲁产玛咖样品中低极性化学成分进行检测,获得各样品的一级质谱指纹谱图和各离子峰的二级质谱数据,并测定各样品促进大鼠睾丸间质细胞增殖活性,采用化学计量学方法主成分分析( PCA)、偏最小二乘法( PLS)和灰色关联度分析( GRA)对所获得的一级质谱数据进行处理后,可有效区分玛咖的不同产地,且筛选出其中具有促大鼠睾丸间质细胞增殖活性的可能成分,进而通过二级质谱数据分析得到可能活性成分的结构。实验结果表明,玛咖低极性成分具有很好的促大鼠睾丸间质细胞增殖活性,其中活性较强的主要为N-benzylhexadecanamide和N-benzy-(9Z,12Z,15Z)-octadecatrien-amide。本方法为简单、快速分析中药中促睾丸间质细胞增殖活性成分筛选方法提供了借鉴。 相似文献
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Ligia Fernanda Ceole Mychelle Vianna Pereira Companhoni Sheila Mara Sanches Lopes Arildo José Braz de Oliveira Regina Aparecida Correia Gonçalves Benedito Prado Dias Filho 《Natural product research》2020,34(11):1558-1562
AbstractThe antiviral potential of natural polysaccharide compounds has been demonstrated, especially against enveloped viruses and members of the Herpesviridae family. Two polysaccharide fractions obtained from Stevia rebaudiana (Bertoni) leaves, that were active against Herpes simplex virus type 1 (HSV-1) were studied to investigate their mode of action. Both polysaccharides - SFW (crude faction) and SSFK (homogeneous alkaline fraction) - exerted antiviral effects on the initial stages of HSV-1 infection by inhibiting viral adsorption and penetration. When added after virus internalization, both fractions decreased plaque size. The effect of the fractions was confirmed by investigating viral glycoprotein expression. Based on the mode of action of the polysaccharides demonstrated in the present work and on their selectivity index, the polysaccharides obtained from S. rebaudiana could be an alternative treatment of infections caused by HSV-1. 相似文献
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小刺猴头菌子实体多糖经乙醇分级和Sepharose CL-6B柱层析,得到多糖HPⅡ.经Sephadex G-100柱层析,高压玻璃纤维纸电泳,比旋光度测定等方法鉴定:HPⅡ在相对分子质量大小和极性上都较为均一.经部分酸水解、高碘酸氧化、Smith降解、IR分析、甲基化分析、GC和GC/MS联机分析等方法,确定了其结构:(1→6)Glc构成主链的核心结构,在3-O处有分枝,平均每7个己糖残基有3个分枝残基;A,B为侧链结构,其构成成分为Glc和Gal;末端残基为(1→)Glc. 相似文献
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沙棘果皮水溶性多糖H_n的结构研究 总被引:2,自引:0,他引:2
沙棘果皮水溶性多糖经酸性乙醇分级和DEAE -SephadexA - 2 5柱层析纯化 ,得到多糖Hn.经SepharoseCL - 4B柱层析、玻璃纤维纸电泳、比旋光度测定等方法鉴定Hn 为均一多糖 .经唾液淀粉酶解、部分酸水解、高碘酸氧化、Smith降解、甲基化分析及IR ,1 3C -NMR ,GC和GC -MS等方法 ,确定其基本结构中主链由 1→ 4Glc基、1→ 6Man基和 1→ 6Gal基构成 .三者摩尔比为nGlc∶nMan∶nGal=3∶1 .5∶1 ,分支点在 3—O处 ,分支率为 43% ,侧链由 1→ 6Gal基、1→ 4Glc基、末端Glc或末端Ara基构成 . 相似文献
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Armelle Tontsa Tsamo Haruna Mohammed Mustapha Mohammed Peter Papoh Ndibewu Felix Dapare Dakora 《Natural product research》2020,34(8):1158-1162
AbstractCowpea (Vigna unguiculata L. Walp.) is an important grain legume in Africa exhibiting high morpho-genetic diversity. However, not much information exists on the phytochemical profiles of its hulls. This study explored the metabolite profiles of seed-coats from thirteen cowpea accessions of varying phenotypes using UPLC-QTOF-MS and chemometric analysis. A total of 34 secondary metabolites were identified, which comprised phenolic acids, flavonoids, anthocyanins, sphingolipids and fatty acids. Quantification of selected phenolic compounds revealed marked variations among the cowpea accessions. The chemical profiles of the test accessions were distinguished by multivariate analysis, and the results revealed a marked influence of seed-coat pigmentation on the observed differences in their metabolite profiles. Moreover, delphinidin (traces to 2257.6 µg/g), catechin glucoside (traces to 2840.6 µg/g), catechin (traces to 2089.2 µg/g) and epicatechin (26.3 to 3222.7 µg/g) contributed to the segregation amongst the studied samples. The concentrations of the discriminant metabolites were greater in the dark seeded cowpeas compared to their lighter seeded counterparts. The findings represent a useful contribution to the literature on cowpea seed coat metabolites, and also reveal their potential for use in the development of food and pharmaceutical products. 相似文献
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Hua Cheng Yan Jia Ling Wang Xiaoying Liu Guangrong Liu Li Li 《Natural product research》2016,30(1):58-64
A crude polysaccharide possessing antitumour, radiation-resistant and anti-ageing attributes was extracted from Tricholoma matsutake by water extraction and alcohol precipitation. From this crude polysaccharide, a homogeneous polysaccharide, TMP-5II, was successfully purified by Sephacryl S-300 column chromatography. The average molecular weight (Mw) of TMP-5II was 15.76 kDa. Monosaccharide analysis indicated that the homogeneous polysaccharide contained four different residues: d-glucose, d-galactose, d-mannose and d-fucose. Attenuated total reflectance infrared spectroscopy revealed characteristics typical of carbohydrate polymers and a peak typical of a β-type glycosidic bond. TMP-5II was selected for structural characterisation by nuclear magnetic resonance (NMR) analysis. According to 1H NMR, 13C NMR and two-dimensional-NMR analysis, TMP-5II contains two kinds of linkages, β and α, at a ratio of 4:1. Preliminary results indicated that the polysaccharide had (1-4)-beta-pyran glucose as the main chain, and a branched chain in the O-6 location with fucose (1-2) mannose (1-3)-alpha-pyran galactose. 相似文献
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The hypoglycemic and antioxidants activities of the methanol extract of Lepidium sativum seeds was tested in alloxan-induced diabetic male rats. Thirty male albino rats weighing 190–200 g were divided into five groups as follows: negative control, positive control and three diabetic groups treated with three concentrations of L. sativum methanol extract for four weeks. Induction of hyperglycemia in the positive control group increased blood glucose, glycated hemoglobin A1c, immunoglobulins, liver enzyme, lipid peroxide and kidney function, total cholesterol, low-density lipoproteins, very low-density lipoproteins and decreased antioxidants and high-density lipoproteins compared with the negative control. Furthermore, pancreas tissues showed pathological changes compared with the negative control. Treating the diabetic rats with L. sativum methanol extract decreased blood sugar and restored all biochemical and histological changes to the normal. It could be concluded that L. sativum methanol extract succeeded in controlling diabetes, increasing antioxidants and ameliorating lipid profile. 相似文献
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The structural properties and Angiotensin-I converting enzyme (ACE) inhibition activities of a polysaccharide (PGE) extracted from Gastrodia elata Blume were investigated. PGE was extracted using hot water and purified by Sephadex G-200 followed by ultra-filtration. The structural characterisation of PGE was analysed by FT–IR, NMR spectroscopy, specific rotation determination, periodate oxidation-smith degradation, methylation analysis, GC–MS and Congo red test. The results revealed that PGE was composed by glucose, with an average molecular weight of 1.54 × 103 kDa. The structure of PGE was 1→3 and 1→4,6-branched-glucopyranose that had a linear backbone of (1 → 4)-linked-d-glucopyranose (Glcp). ACE-inhibitory activity results showed that PGE was efficient to inhibit ACE and the IC50 value was 0.66 mg/mL. 相似文献
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玉米芯酸提水溶性多糖CCCP的分离纯化和结构研究 总被引:2,自引:0,他引:2
玉米芯用PH=3的HCl煮提得到酸提水溶性粗多糖.该粗多糖组成为Glc,Xyl,Gal,经乙醇分级和Sepharose CL-6B柱层析纯化,得到多糖CCCP.经Sephadex A-25柱层析、比旋光度测定、醋酸纤维薄膜电泳等方法鉴定CCCP为均一多糖.经唾液淀粉酶解、纤维素酶解、部分酸水解、高碘酸氧化、Smith降解、甲基化分析及IR,GC和GC/MS等方法分析表明:CCCP为少分枝结构;主链由吡喃型(1→3)Xyl构成,在O(4)处有分枝;支链主要由(1→4)Glc构成,在O(6)处有分枝,支链还存在1→3,1→6键型连接的Glc,Gal;末端基为Xyl,Glc,Gal. 相似文献
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