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61.
Abstract

This work aimed at evaluating the prebiotic potential of the aqueous extract and crude polysaccharides from Agave sisalana boles by an in vitro screening. Crude polysaccharides were obtained from the aqueous bole extract by precipitation with acetone and resuspension in water. The liquid extract and the polysaccharide solution were then spray dried and submitted to thermal analysis and quantification of metabolites. Prebiotic activity was checked on probiotic strains belonging to the Lactobacillus genus using inulin, fructo-oligosaccharides, fructose and glucose as positive controls. The powder of A. sisalana bole extract, which has recently been identified as a rich source of inulin, exhibited higher potential of fermentation compared with crude polysaccharides.  相似文献   
62.
以680nm处的透光率作为澄清度的指标,比较明胶、淀粉、蛋清和壳聚糖4种澄清剂在不同浓度、温度、处理时间下的澄清效果。结果表明:明胶和壳聚糖澄清效果较好,蛋清次之,而淀粉几乎无澄清作用。0.16%的明胶和0.08%的壳聚糖澄清效果最佳,透光率分别为84.02%和84.44%。蛋清的澄清速度较明胶和壳聚糖慢;温度对蛋清和壳聚糖几乎无影响,但明胶随处理温度升高透光率下降。  相似文献   
63.
尖海龙提取物抗癌作用的研究   总被引:4,自引:0,他引:4  
制备尖海龙提取物,再将其分别作用于Hela,SK-RB-3细胞系,从细胞形态变化,细胞计数,集落形成率,细胞分裂指数变化观察体外药效,结果表明,尖海龙提取物可改变肿瘤的正常生活形态,又可显著抑制肿瘤细胞的增殖,降低集落形成率,减少分裂指数,从而证实尖海龙提取物具有抗癌活性,其在癌症的治疗与预防方面具有实用价值。  相似文献   
64.
采用MTT比色法对体外培养的肿瘤细胞进行细胞毒作用实验,验证槲寄生蛋白注射液体外抗肿瘤效果.并且鉴定这种检测方法的有效性。实验结果表明槲寄生蛋白注射液有一定的体外抗肿瘤效果;MTT比色法是一种可用的体外细胞毒作用检测法,为新药品的开发提供了实验依据。  相似文献   
65.
化香果单宁及其有关化合物   总被引:3,自引:0,他引:3  
用60%丙酮水溶液室温浸化香果,使用几种凝胶柱层析,从化香果丙酮水提取物中分离了5种化合物。根据化学反应及真实样品共层析和氢核磁共振谱分析,其中四种化合物被鉴定为鞣花酸、没食子酸、英国栎鞣花素和木麻黄亭,另一种化合物待鉴定。  相似文献   
66.
    
Honokiol and magnolol in Magnoliae Cortex, one of five medical herbal ingredients of Hange-koboku-to dried extract granules, have pharmacological activities, including decreasing anxiety and improving sleep. Here, we present a method employing aqueous extraction, followed by high-performance liquid chromatography with fluorescence detection, for the simultaneous determination of honokiol and magnolol in Hange-koboku-to dried extract granules. Excitation and emission wavelengths were set at 304 nm and 340 nm, respectively, for honokiol detection until 9 min, then the emission wavelength was shifted at 405 nm for magnolol detection. The regression equations for honokiol and magnolol in standard aqueous solutions showed good linearity in the range of 0.05–1 µg/mL with lower limits of detection (signal-to-noise ratio of 3) of 0.0047 and 0.0061 µg/mL, respectively. The coefficients of variation were less than 5.6%. It was found that Hange-koboku-to dried extract granules (1.00 g) contains honokiol (3.30 ± 0.21 mg; range, 3.08 to 3.63 mg) and magnolol (5.40 ± 0.37 mg; range, 4.80 to 5.80 mg) (mean ± S.D., n = 5). Recovery tests were satisfactory (90.7–104.8%).  相似文献   
67.
    
In this study, a rapid and sensitive ultra-high performance liquid chromatography-tandem mass spectrometry method was established for the simultaneous determination of four Vitexin-4“-O-glucoside (VOG), Vitexin-2”-O-rhamnoside (VOR), vitexin (VIT), and hyperoside (HP) in plasma, which are representative flavonoids constituents of hawthorn leaves. The four components were separated by CORTECS UPLC C18 column (100 × 3.0 mm, 1.6 µm), using acetonitrile-water containing 0.02% formic acid and 2 mmol/L ammonium formate as the mobile phase, the gradient elution flow rate was 0.30 mL/min. The analyte was quantified using an electrospray ionization triple quadrupole mass spectrometer. The analytes and baicalin internal standard were performed at m/z 593.2/413.2 for VOG, m/z 577.2/413.1 for VOR, m/z 431.1/310.9 for VIT, m/z 463.2/300 for HP and m/z 445.1/269 for internal standard. Among the four flavonoids, the correlation coefficient of the standard curve of each component is between 0.9939 and 0.9987. After oral administration of hawthorn leaf extract, VOG and VOR showed similar pharmacokinetic characteristics; VIT was eliminated in the body more slowly than the other three flavonoids and distributed more in the tissues; HP can be quickly absorbed in the blood. The developed analytical method has high sensitivity, precision, and accuracy with no interference from plasma components and has been successfully used in pharmacokinetic studies.  相似文献   
68.
    
Green synthesis of Ag nanoparticles (AgNPs) by using the plant extract is a very important strategy to gain efficient antimicrobial agents with strong antimicrobial activity and low toxicity. In this study, jujube seed extract (JSE) is utilized to green synthesis of AgNPs by both hydrothermal process and solution-based approaches. UV–vis absorption spectroscopy and infrared spectroscopy (FTIR) spectra confirm that jujube seed extract functionalized Ag nanoparticles are formed by both approaches and jujube seed extract covered on the surface of Ag nanoparticles. Transmission electron microscopy (TEM) images indicate that the JSE-AgNPs are spherical with the average diameter of 17.7 and 14.2 nm for the hydrothermal process and solution-based approaches, respectively. X-ray diffraction (XRD) results indicate that the JSE-AgNPs prepared by both approaches have face-centered cubic crystal structure. The antimicrobial activity test reveals that minimum inhibitory concentrations (MIC) of JSE-AgNPs by the solution-based method are 62.5, 125, and 62.5 µg mL−1 against Escherichia coli, Staphylococcus aureus, and Candida albicans, respectively. These results imply that the JSE-AgNPs have potential to be developed as efficient antimicrobial agents.  相似文献   
69.
    
Chemical diversification of substances present in natural product extracts can lead to a number of natural product-like compounds with a better chance of desirable bioactivities. The aim of this work was to discover unprecedented chemical conversion and produce new compounds through a one-step reaction of substances present in the extracts of marine sponges. In this report, a new unnatural tetracyclic bromopyrrole-imidazole derivative, rac-6-OEt-cylindradine A (1), was created from a chemically diversified extract of the sponge Petrosia (Strongylophora) sp. We also confirmed that 1 originated from naturally occurring (-)-cylindradine A (2) via a new reaction pattern. Moreover, (-)-dibromophakellin (3) and 4,5-dibromopyrrole-2-carboxylic acid (4), as well as 2, were reported herein for the first time in this genus. Studies on the possible reaction mechanism and bioactivities were also conducted. The results indicate that the direct chemical diversification of substances present in natural product extracts can be a speedy and useful strategy for the discovery of new compounds.  相似文献   
70.
    
Premature ovarian failure (POF) is described as a loss of oocytes and the absence of folliculogenesis and is considered an adverse effect of chemotherapeutic drugs, which leads to infertility. Subsequently, the existing inquiry was achieved by exploring the potential suspicious influences of lemon peel extract (LPE), and resveratrol (RES) on cyclophosphamide (CPA) induced-POF. The results showed that CPA-induced POF significantly decreased serum estradiol (E2) and progesterone levels, along with a considerable rise in serum luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels. Moreover, CPA administration to rats significantly increased the serum level of Malondialdehyde (MDA) and significantly lowered the levels of reduced glutathione (GSH) and superoxide dismutase (SOD); in addition, it increased nuclear factor kappa B (NF-κB) levels, tumor necrosis factor-α (TNF-α), as well as cyclooxygenase 2 (COX-2) with the spread expression of inducible nitric oxide synthase (iNOS) mRNA levels and caspase-3 (Casp3) levels in ovarian tissues versus the control rats. However, treatment with LPE and RES suppressed the triggering of NF- κB pathways, evidenced by a considerable reduction in Casp3 & iNOS mRNA expression level and significant ameliorative effects in all evaluated parameters, as confirmed by the histological and immunohistochemical investigation when comparing the model group. In overall findings, both lemon peel extract and resveratrol can mitigate the adverse effects of CPA-induced POF. Most crucially, its combination therapy is a promising pharmacological agent for this disease.  相似文献   
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