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《Analytical letters》2012,45(1):47-65
Abstract

This study aimed at evaluating the in vitro antioxidant activity of water and ethanol extracts of juniper (Juniperus communis L., Family Cupressaceae) fruit. The antioxidant properties of both Juniper extracts were studied using different antioxidant assays, including reducing power, free radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, and metal chelating activities. Both the water and the ethanol extracts exhibited strong total antioxidant activity. The concentrations of 20, 40, and 60 µg/mL of water and ethanol extracts of juniper fruit showed 75%, 88%, 93%, 73%, 84%, and 92% inhibition on peroxidation of linoleic acid emulsion, respectively. On the other hand, 60 µg/mL of standard antioxidant such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and α‐tocopherol exhibited 96, 96, and 61 inhibitions on peroxidation of linoleic acid emulsion, respectively. However, both extracts of juniper had effective reducing power, free radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, and metal chelating activities at these same concentrations (20, 40, and 60 µg/mL). Those various antioxidant activities were compared to BHA, BHT, and α‐tocopherol as standard antioxidants. In addition, total phenolic compounds in both aqueous and ethanolic juniper extracts were determined as gallic acid equivalents. Accordingly, these results indicate that juniper has in vitro antioxidant properties and these may be major reasons for the inhibition of lipid peroxidation properties.  相似文献   
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Ricinine (1), a known major alkaloid in Ricinus communis plant, was used as a starting compound for the synthesis of six ricinine derivatives; two new and four known compounds. The new derivatives; 3-amino-5-methyl-1H-pyrazolo[4,3-c]pyridin-4(5H)-one (2), and 3-amino-5-methyl-1-(phenylsulfonyl)-1H-pyrazolo[4,3-c]pyridin-4(5H)-one (3), as well as the previously prepared derivatives (47) were subjected for antimicrobial and antiquorum-sensing evaluation in comparison to different R. communis extracts. Acetyl ricininic acid derivative (5) showed the highest antimicrobial activity among all tested derivatives against Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeuroginosa and Candida albicans. However, compound 7 (4-methoxy-1-methyl-2-oxo-1,2-dihydropyridine-3-carboxamide) showed the highest antiquorum-sensing activity among all tested compounds and extracts. These findings proved the usefulness of ricinine as a good scaffold for the synthesis of new antimicrobial and antiquorum-sensing derivatives in spite of its poor contribution to the antimicrobial activity of the plant extracts.  相似文献   
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Ferula communis is a showy herbaceous plant typical of the Mediterranean area where it is used as a traditional medicine. The plant is a source of bioactive compounds such as daucane sesquiterpenes and prenylated coumarins. In Italy, most of phytochemical studies focused on Sardinian populations where poisonous and nonpoisonous chemotypes were found, while investigations on peninsular populations are scarce. In this work, we report the chemical characterisation of the essential oils obtained from different parts of F. communis growing in central Italy. The chemical profiles of the plant parts, as detected by GC-FID and GC-MS, were different from each other and from those reported in insular populations. Notably, α-pinene (10.5%), γ-terpinene (7.6%) and hedycariol (8.4%) were the major volatile constituents in flowers; α-pinene (55.9%), β-pinene (16.8%) and myrcene (5.9%) in fruits; β-eudesmol (12.1%), α-eudesmol (12.1%) and hedycariol (10.3%) in leaves; (E)-β-farnesene (9.5%), β-cubebene (8.2%) and (E)-caryophyllene (7.2%) in roots. The volatile profiles detected did not allow to classify the investigated central Italy population into the poisonous and nonpoisonous chemotypes previously described in Sardinia.  相似文献   
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The present study investigates the green synthesis of stable silver nanoparticles using Juniperus communis leaf aqueous extract at room temperature. Synthesized silver nanoparticles (AgNPs) were characterized with different techniques such as UV–vis spectroscopy, Fourier transforms infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), Scanning electron microscopy (SEM-EDAX) and electrochemical method. Photocatalytic and anti-bacterial activities of synthesized AgNPs are evaluated based on the obtained result showed an efficient inhibition growth for gram negative P. Aeruginosa, E. Coli, and gram positive bacteria S.aureus. The AgNPs exhibited an excellent photocatalytic activity toward the degradation of methylene blue both indoor and outdoor, under sunlight, an efficiency of 95% was achieved. As an easy and environmentally friendly process, AgNPs based on Juniperus communis leaf extract could be applied for the degradation of pollutants and wastewater treatment.  相似文献   
7.
用火焰原子吸收光度法测定了6个品种巴旦杏仁中的K,Na,ca,Fe,cu,Zn,Mn,Mg等8种元素含量,并用紫外-可见分光光度法测定了总黄酮含量。结果表明,巴旦杏仁含有丰富的人体必需的微量元素,其中纸皮巴旦杏仁中K,Ca,Mn,Zn的含量普遍高于其它品种。微量元素测定方法的回收率在96.9%~101.7%之间,RSD值在0.74%~1.85%之间。总黄酮含量在不同品种之间呈现出较大差异,其中晚丰巴旦杏仁中总黄酮量高达1.75%,明显高于其它品种。为新疆巴旦杏资源的进一步研究和综合开发利用提供了新的科学依据。  相似文献   
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Background: Myrtus communis (M. communis) is a wild aromatic plant used for traditional herbal medicine that can be demonstrated in insecticidal, antioxidant, anti-inflammatory, and antimicrobial activity of its essential oils (MCEO). Aim: The present study aimed to evaluate the prophylactic effects of M. communis essential oil (MCEO) against chronic toxoplasmosis induced by the Tehran strain of Toxoplasma gondii in mice. Methods: Gas chromatography/mass spectrometry (GC/MS) analysis was performed to determine the chemical composition of MCEO. Mice were then orally administrated with MCEO at the doses of 100, 200, and 300 mg/kg/day and also atovaquone 100 mg/kg for 21 days. On the 15th day, the mice were infected with the intraperitoneal inoculation of 20–25 tissue cysts from the Tehran strain of T. gondii. The mean numbers of brain tissue cysts and the mRNA levels of IL-12 and IFN-γ in mice of each tested group were measured. Results: By GC/MS, the major constituents were α-pinene (24.7%), 1,8-cineole (19.6%), and linalool (12.6%), respectively. The results demonstrated that the mean number of T. gondii tissue cysts in experimental groups Ex1 (p < 0.05), Ex2 (p < 0.001) and Ex3 (p < 0.001) was meaningfully reduced in a dose-dependent manner compared with the control group (C2). The mean diameter of tissue cyst was significantly reduced in mice of the experimental groups Ex2 (p < 0.01) and Ex3 (p < 0.001). The results demonstrated that although the mRNA levels of IFN-γ and IL-12 were elevated in all mice of experimental groups, a significant increase (p < 0.001) was observed in tested groups of Ex2 and Ex3 when compared with control groups. Conclusion: The findings of the present study demonstrated the potent prophylactic effects of MCEO especially in the doses 200 and 300 mg/kg in mice infected with T. gondii. Although the exceptional anti-Toxoplasma effects of MCEO and other possessions, such as improved innate immunity and low toxicity are positive topics, there is, however, a need for more proof from investigations in this field.  相似文献   
9.
Ricinine and Its Transformations   总被引:1,自引:0,他引:1  
Ricinine was isolated fromRicinus communisL. Its derivatives were obtained  相似文献   
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In this study, a liquid-phase separation platform consisting of tandem lectin affinity chromatography was introduced for the selective capturing of sub-glycoproteomics that are affected in cancers, e.g. breast cancer. The platform is comprised of three monolithic columns with surface immobilised lectins including concanavalin A (Con A), wheat germ agglutinin (WGA) and Ricinus communis agglutinin-I (RCA-I). While WGA and Con A have specificities directed towards the core portion of N-glycans on the glycoprotein surface, RCA-I specifically interacts with the non-reducing terminal moieties of the outer chain structures of N-glycans. The effects of the order in which the three lectin columns were arranged in the tandem columns format were evaluated. The most suitable order proved to be WGA → Con A → RCA-I (denoted as WCR) as far as the number of captured proteins was concerned. The WCR tandem columns allowed the capture of 113 and 112 proteins from disease-free and breast cancer sera, respectively, corresponding to 75 and 65 non-redundant proteins, respectively. Using mass spectral count ratios and Q-Q plots yielded a panel of 23 non-redundant differentially expressed proteins (i.e. a panel of 23 candidate markers), which should in principle be more representative of a pathophysiological state than a single marker candidate.  相似文献   
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