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311.
于海洋  晏嘉泽  郭明  靳艳 《色谱》2013,31(4):362-366
通过水提、酸沉法得到锦灯笼果实提取物,其中蛋白质含量为188 mg/g(以提取物干重计),共含有18种氨基酸,其中8种人体必需氨基酸占氨基酸总量的31%。基于鸟枪法蛋白质组学的分析方法,用纳升级反相液相色谱-串联质谱(nano-RPLC-MS/MS)系统分析锦灯笼果实提取物中蛋白质的酶解产物,结合数据库检索,共鉴定得到60种蛋白质;通过生物信息学分析,得到锦灯笼提取物中的蛋白质具有催化活性、抗氧化活性、酶调节活性、养分贮液囊活性、运输活性、结合活性六大生物活性,其中鉴定到与抗氧化相关的蛋白质有3种,为锦灯笼中蛋白质的功能性质的进一步研究奠定了基础。  相似文献   
312.
An efficient separation process of flavonoid from Taxus wallichiana var. mairei remainder extracts free of taxoids was developed in this study. AB‐8 macroporous resin and polyamide resin offered the fine adsorption capacity, and its adsorption rate at 30°C fitted well to the Langmuir and Freundich isotherms. Resin dynamic adsorption and desorption experiments were conducted to optimize the separation process of total flavonoids from T. wallichiana var. mairei remainder extracts free of taxoids. The optimum parameters for adsorption by AB‐8 resin were as follows: (1) the concentration of flavonoids in a sample solution of 5.61 mg/mL with a processing volume of 2 bed volume (BV) (60 mL); (2) for desorption, ethanol–water (80:20, v/v), with 6 BV as an eluent at a flow rate of 2 BV/h. After a one‐run treatment with AB‐8 resin, the content of flavonoids was increased 5.10‐fold from 4.05 to 20.65%. The optimum parameters for adsorption by polyamide resin were as follows: processing volume of 2 BV (30 mL); for desorption, ethanol–water (70:30, v/v), with 8 BV as an eluent at a flow rate of 2 BV/h. After one‐run treatment with polyamide resin, the content of total flavonoids increased from 20.65 to 65.21%. The method will provide a potential approach for large‐scale separation and purification of flavonoid for its wide pharmaceutical use.  相似文献   
313.
The components of the essential oils obtained from different parts of Daucus carota L. var. sativa Hoffm were analyzed. The percentages of the essential oils extracted are 0. 27% (mL/100 g material) for the flowers, 0. 07% for the stems and leaves and 0. 01% for the roots. Fifty-four, Sixty-six and Thirty-three compounds were, respectively,separated and identified from the flowers, the stems and leaves and the roots, among which unsaturated alkene compounds are thirty-nine, thirty-nine and twenty-one, respectively, accounting in turn for up to 90. 21%, 90. 49% and 72. 65% of the total essential oils. Because alkene compounds have double bonds that are easily oxidized, it can be inferred that the components of the essential oils in the different parts of Daucus carota L. var. sativa Hoffm should show an activity of the anti-formation of free radicals to some extent.  相似文献   
314.
There is an increasing commercial demand for nanoparticles due to their wide applicability in various areas such as electronics, catalysis, chemistry, energy, and medicine. Recently, researchers have tried to synthesize the chemotherapeutic drugs from metallic nanoparticles especially gold and silver nanoparticles. In the current study, silver nanoparticles using Spinacia oleracea L. leaf aqueous extract (AgNPs) are reported for the first time to exert a dietary remedial property compared to doxorubicin in an animal model of acute myeloid leukemia. The synthesized AgNPs were characterized using different techniques including UV-Vis., EDS, TEM, FT-IR, and FE-SEM. UV-Vis. indicates an absorption band at 462 nm that is related to the surface plasmon resonance of AgNPs. In EDS, metallic silver nanocrystals indicated an optical absorption peak at roughly 4keV. TEM and FE-SEM images exhibited a uniform spherical morphology and diameters of 20–40 nm for the nanoparticles. FT-IR findings suggested antioxidant compounds in the nanoparticles were the sources of reducing power, reducing silver ions to AgNPs. In vivo design, induction of acute myeloid leukemia was done by 7,12-Dimethylbenz[a]anthracene in 75 mice. Then, the animals were randomly divided into six subgroups, including control, untreated, AgNO3, S. oleracea, AgNPs, and doxorubicin. Similar to doxorubicin, AgNPs significantly (p ≤ 0.01) reduced the pro-inflammatory cytokines, and the total WBC, blast, neutrophil, monocyte, eosinophil, and basophil counts and increased the weight of the body, the anti-inflammatory cytokines and the lymphocyte, platelet, and RBC parameters as compared to the untreated mice. DPPH free radical scavenging test was done to evaluate the antioxidant potentials of AgNO3, S. oleracea, AgNPs, and doxorubicin. DPPH test revealed similar antioxidant potentials for doxorubicin and AgNPs. For the analyzing of cytotoxicity effects of AgNO3, S. oleracea, AgNPs, and doxorubicin, MTT assay was used on HUVEC, Human HL-60/vcr, 32D-FLT3-ITD, and Murine C1498 cell lines. AgNPs similar to doxorubicin had low cell viability dose-dependently against Human HL-60/vcr, 32D-FLT3-ITD, and Murine C1498 cell lines without any cytotoxicity on HUVEC cell line. These results reveal that the inclusion of S. oleracea leaf aqueous extract improves the remedial effects of AgNPs, which led to a significant enhancement in the antioxidant, cytotoxicity, and anti-acute myeloid leukemia potentials of the nanoparticles. It seems that AgNPs can be applied as a chemotherapeutic supplement or drug for the treatment of acute myeloid leukemia in the clinical trial.  相似文献   
315.
Citrus aurantium L. var. amara Engl is a member of genus Citrus (Rutaceae) and has been used in Chinese medicine with the effectiveness of digestant and expectorant. Ultrasonic‐assisted extraction process for maximum flavonoids from the flower of Citrus aurantium L. var. amara Engl was investigated by response surface methodology. Through single factor experiment, ranges of the main variables (including ethanol concentration, solid/liquid ratio, extraction time and temperature) affecting the extraction yield of flavonoids were confirmed. Box–Behnken central composite design consisting of 24 experimental runs and 5 replicates at zero point was then applied and a regress model was obtained to predict the optimal extraction yield. The ANOVA indicated that the regression equation fits very well with the actual situation, reflecting the relationship between the extraction yield of flavonoids and extraction conditions. The optimal conditions were as follows: extraction temperature 72.11°C, time 51.89 min, ethanol concentration 51.19% and liquid/solid ratio of 40:10. Under the optimal conditions, the maximum response value of yield (1.88%) was consistent with the experimental value (1.87%), indicating the feasibility and validation of response surface methodology in optimizing the extraction of flavonoids from the flower of Citrus aurantium L. var. amara Engl.  相似文献   
316.
 Gas chromatography/inductively coupled plasma mass spectrometry (GC/ICP MS) coupled with solid phase micro extraction can provide a simple, extremely selective and sensitive technique for the analysis of volatile sulfur and selenium compounds in the hea  相似文献   
317.
Cedronella canariensis is a lemon-scented species of the family Lamiaceae endemic to the Canary Islands where it is used in the traditional medicine to prepare infusions or inhalations for anti-catarrhal, tonic, diuretic, hypoglycaemiant, hypotensive, anti-inflammatory and decongestant of the respiratory tract. In this work we investigated for the first time the antioxidant activity of the essential oil and its inhibitory effects on tumour cells (A375, MDA-MB-231, HCT 116) proliferation by DPPH, ABTS, FRAP and MTT assays, respectively. The oil, analysed by GC-ionisation flame detector and GC–MS, was characterised by pinocarvone (58.0%) and β-pinene (10.8%) as the major constituents, being typical of the chemotype ‘canariensis’. Noteworthy was the cytotoxic activity of the oil against the tumour cells examined, with IC50 values of 4.3, 7.3 and 11.4 μg/mL on A375, MDA-MB-231 and HCT 116 tumour cells, respectively, as well as the scavenging activity against the ABTS radical (IC50 of 10.5 μg/mL).  相似文献   
318.
A new tricyclic alkaloid named portulacatone ( 1 ), i.e., 5,6‐dihydro‐8,9‐dihydroxy‐11H‐pyrrolo[2,1‐b] [3]benzazepin‐11‐one, together with eight known compounds, methyl 4‐hydroxyphenylacetate ( 2 ), p‐hydroxybenzaldehyde ( 3 ), vanillin ( 4 ), protocatechualdehyde ( 5 ), p‐hydroxybenzoic acid ( 6 ), iseluxine ( 7 ), oleracein E ( 8 ), and (+)‐(R)‐feruloyl malate ( 9 ) were isolated from aerial parts of Portulaca oleracea L. Their structures were elucidated based on spectroscopic analyses. Among them, compounds 1 – 7 and 9 were isolated from this medicinal plant for the first time. Compounds 1 and 7 showed dose‐dependent scavenging activities against DPPH (2,2‐diphenyl‐1‐picryl‐hydrazyl) free radical, with EC50 values of 14.36 μM and 9.98 μM , respectively, more potent than the natural antioxidant vitamin C (EC50 20.72 μM ).  相似文献   
319.
A new triterpenoid bearing octacosanoate, named taraxer-3β-yl octacosanoate (1), together with 13 known compounds (214), was isolated from the ethanol extract of the stems and roots of Clerodendrum philippinum var. simplex. The structure of taraxer-3β-yl octacosanoate (1) was elucidated by extensive spectroscopic analysis. Uncinatone (8) and clerodenone A (10) exhibited inhibition of lipopolysaccharide-induced nitric oxide production in RAW 264.7 macrophages with IC50 values of 12.50 and 3.18 μM, respectively.  相似文献   
320.
Two new homo‐aro‐cholestane glycosides and a new cholestane glycoside, along with three known saponins, were isolated from the 95% EtOH extract of the roots and rhizomes of Paris polyphylla var. pseudothibetica. The structures of the new compounds were elucidated as 3βO‐{α‐L ‐rhamnopyranosyl‐(1→4)‐α‐L ‐rhamnopyranosyl‐(1→4)‐[α‐L ‐rhamnopyranosyl‐(1→2)]}‐β‐D ‐glucopyranosylhomo‐aro‐cholest‐5‐ene‐26‐Oβ‐D ‐glucopyranoside (parispseudoside A, 1 ), 3βOα‐L ‐rhamnopyranosyl‐(1→2)‐β‐D ‐glucopyranosylhomo‐aro‐cholest‐5‐ene‐26‐Oβ‐D ‐glucopyranoside (parispseudoside B, 2 ), and (25R)‐3βO‐{α‐L ‐rhamnopyranosyl‐(1→4)‐α‐L ‐rhamnopyranosyl‐(1→4)‐[α‐L ‐rhamnopyranosyl‐(1→2)]}‐β‐D ‐glucopyranosyl‐cholesta‐5,17(20)‐diene‐16,22‐dione‐26‐Oβ‐D ‐glucopyranoside (parispseudoside C, 3 ) by spectroscopic methods, including 1D‐ and 2D‐NMR, and MS experiments, as well as chemical evidences.  相似文献   
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