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排序方式: 共有361条查询结果,搜索用时 31 毫秒
31.
Righi AA Alves TR Negri G Marques LM Breyer H Salatino A 《Journal of the science of food and agriculture》2011,91(13):2363-2370
BACKGROUND: Chloroform, ethyl acetate and methanol extracts of a sample of red propolis from the state of Alagoas (northeast Brazil) were analyzed by gas chromatography–mass spectrometry and high‐performance liquid chromatography–diode array detection–electrospray ionization‐mass spectrometry. Antimicrobial and antioxidant activities were also obtained. RESULTS: The propolis sample contained low content of narigenin‐8‐C‐hexoside, this being the first report of a C‐glycoside in propolis. The main constituent found was characterized as 3,4,2′,3′‐tetrahydroxychalcone. Other important constituents were the chalcone isoliquiritigenin, the isoflavans (3S)‐vestitol, (3S)‐7‐O‐methylvestitol, the pterocarpan medicarpin, the phenylpropenes trans‐anethol, methyl eugenol, elimicin, methoxyeugenol and cis‐asarone, and the triterpenic alcohols lupeol and α‐ and β‐ amyrins. The methanol extract exhibited high antioxidant activities by 2,2‐diphenyl‐1‐picrylhydrazyl and β‐carotene/linoleic acid assay methods, and antimicrobial activity toward Gram‐positive and Gram‐negative bacteria. CONCLUSION: Structures are suggested for new substances never before seen in any kind of propolis. This is the first report of 3,4,2′,3′‐tetrahydroxychalcone and a flavone C‐glycoside in a propolis sample. Copyright © 2011 Society of Chemical Industry 相似文献
32.
Giuseppina Adiletta Loredana Liguori Donatella Albanese Paola Russo Marisa Di Matteo Alessio Crescitelli 《Food and Bioprocess Technology》2017,10(9):1631-1641
A preliminary characterization of two new soft-seeded pomegranate varieties (MR-100® and KINGDOM®) based on their main physico-chemical and nutritional parameters was reported. The two varieties showed significant differences (p ≤ 0.05) in polyphenols, anthocyanins and antioxidant activity. Kingdom pomegranate had higher polyphenols (2524.73 mg GAE/L), anthocyanins (752.49 mg C3gE/L) and antioxidant activity (EC50 13.58 μL/mL) than MR-100 (1792.74 mg GAE/L, 141.29 mg C3gE/L and EC50 47.53 μL/mL, respectively). Moreover, minimally processed arils of the two varieties were packaged in semipermeable and micro-perforated film at 5 °C, and the quality changes that occurred during storage condition (15 days) were investigated. During storage, Kingdom arils exhibited a better performance in terms of antioxidant activity, polyphenols and anthocyanin content with respect to MR-100. Furthermore, the packaging systems did not affect the estimated quality parameters for both varieties. Based on the sensory evaluation and microbial counts, both aril varieties reached, at 15-day storage, suitable values for commercial purpose. 相似文献
33.
Giuseppina Rea Amina AntonacciMaya Lambreva Sandro PastorelliArianna Tibuzzi Simone FerrariDirk Fischer Udo JohanningmeierWieslaw Oleszek Teresa DoroszewskaAngela Maria Rizzo Patrizia V.R. BerselliBruno Berra Alessandra BertoliLuisa Pistelli Barbara RuffoniCarole Calas-Blanchard Jean Louis MartySimona Carmen Litescu Mirela DiaconuEleftherios Touloupakis Demetrios GhanotakisMaria Teresa Giardi 《Trends in Food Science & Technology》2011,22(7):353-366
34.
Adolphsen Chris Litke Alan Schwarz Andreas Turala Michal Anzivino Giuseppina Horisberger Roland Hubbeling Leonardus Hyams Bernard Breakstone Alan Cence Robert Parker Sherwood Walker James T. 《IEEE transactions on nuclear science》1986,33(1):57-59
Silicon detectors with 256 strips, having a pitch of 25 ?m, and connected to two 128 channel NMOS VLSI chips each (Microplex), have been tested in relativistic charged particle beams at CERN and at the Stanford Linear Accelerator Center. The readout chips have an input channel pitch of 47.5 ?m and a single multiplexed output which provides voltages proportional to the integrated charge from each strip. The most probable signal height from minimum ionizing tracks was 15 times the rms noise in any single channel. Two-track traversals with a separation of 100 ?m were cleanly resolved. 相似文献
35.
Combining Singular-Spectrum Analysis and neural networks for time series forecasting 总被引:1,自引:0,他引:1
In this paper, we propose a combination of an adaptive noise-reduction algorithm based on Singular-Spectrum Analysis (SSA) and a standard feedforward neural prediction model. We test the forecast skill of our method on some short real-world and computergenerated time series with different amounts of additive noise. The results show that our combined technique has better performances than those offered by the same network directly applied to raw data, and therefore is well suited to forecast short and noisy time series with an underlying deterministic data generating process (DGP). 相似文献
36.
37.
Robot programming languages are emerging from their experimental stage and entering an assessment phase. Their main features are illustrated and a parallel with ADA is proposed. The comparison is positive for ADA, in the sense that ADA provides most of the required capabilities. The ability of reasoning on object models and taking decisions will play an increasing role in the future. In this case the role of ADA would possibly change and its interest as robot programming language decrease. 相似文献
38.
39.
Phenolic compounds in olive oil and olive pomace from Cilento (Campania,Italy) and their antioxidant activity 总被引:3,自引:0,他引:3
Giuseppina Cioffi Maria Sabina Pesca Paolo De Caprariis Alessandra Braca Lorella Severino Nunziatina De Tommasi 《Food chemistry》2010
Virgin olive oil (VOO) has nutritional and sensory characteristics that make it unique and a basic component of the Mediterranean diet. Its importance is mainly attributed to its richness in polyphenols, which act as natural antioxidants and may contribute to the prevention of several human diseases. In this paper we report the determination and quantification of oleocanthal, one of the main substances responsible for the bitter taste of olive oil, together with a quali-quantitative analysis by HPLC analytical methods of phenolics from Cilento VOO and olive oil pomace. The total phenolic content was also determined and the in vitro antioxidant and free-radical scavenging activities by DPPH test was evaluated. A superoxide anion enzymatic assay was also carried out and the results were confirmed by the inhibition of xanthine oxidase activity assay. The possible protective role played by VOO secoiridoids on injurious effects of reactive oxygen metabolites on the intestinal epithelium, using Caco-2 human cell line, was investigated. 相似文献
40.
Iole Pitino Cinzia Lucia Randazzo Giuseppina Mandalari Alberto Lo Curto Richard Martin Faulks Yvan Le Marc Carlo Bisignano Cinzia Caggia Martin Sean John Wickham 《Food microbiology》2010
In the present study six probiotic Lactobacillus rhamnosus strains were investigated for their ability to survive in the human upper gastrointestinal tract through a dynamic gastric model of digestion. MRS broth was used as delivery vehicle and survival was investigated during in vitro gastric and gastric plus duodenal digestion. Results highlighted that all tested strains showed good survival rate during both gastric and duodenal digestion. In particular, three strains exhibited a great survival showing a recovery percentage in the range between 117 and 276%. In agreement with survival data, high lactic acid production was detected for all strains, confirming their metabolic activity during digestion. 相似文献