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排序方式: 共有353条查询结果,搜索用时 15 毫秒
61.
Renata Quartieri Nascimento Cludio Vaz Di Mambro Ribeiro Nelson Barros Colauto Larissa da Silva Paulo Vitor Frana Lemos Ederlan de Souza Ferreira Giani Andrea Linde Bruna Aparecida Souza Machado Pedro Paulo Lordelo Guimares Tavares Aline Camaro Telles Biasoto Marcelo Andres Umsza Guez Natlia Carvalho Denílson de Jesus Assis Jania Betnia Alves da Silva Carolina Oliveira de Souza 《Molecules (Basel, Switzerland)》2022,27(20)
Edible insects are a potential alternative food source of high feed conversion efficiency and protein content. Zophobas atratus is an edible insect that adapts to different diets, enabling sustainable rearing by adding value to by-products and agro-industrial residues. This study aimed to evaluate the performance and nutritional characterization of Zophobas atratus larvae fed with different proportions of grape residue. Physicochemical analysis of the diets and larvae (AOAC procedures), fatty acid profile (chromatographic techniques), metals and non-metals (inductively coupled plasma optical emission spectrometry), larval mass gain, feed conversion efficiency, and mortality rate were assessed. The replacement of 25% of the conventional diet with grape residue increased lipid, ash, and fiber contents and reduced protein, carbohydrates, and energy. It promoted greater mass gain, lower mortality rate, and reduced larval growth time by 51%. Among the replacements, 25% resulted in the second-highest content of calcium, sodium, magnesium, and zinc, and the lowest content of potassium and phosphorus in the larvae. The 100% replacement resulted in the highest amounts of C18:2n6 (27.8%), C18:3n3 (2.2%), and PUFA (30.0%). Replacing 25% of the conventional diet with grape residue is equivalent to the conventional diet in many aspects and improves several larvae performance indices and nutritional values. 相似文献
62.
Attilio Anzano Bruna de Falco Mohammad Ammar Annarita Ricciardelli Laura Grauso Mohammed Sabbah Rosanna Capparelli Virginia Lanzotti 《Molecules (Basel, Switzerland)》2022,27(24)
Moringa oleifera is a traditional food crop widespread in Asiatic, African, and South American continents. The plant, able to grow in harsh conditions, shows a high nutritional value and medicinal potential evidencing cardioprotective, anti-inflammatory, antioxidant, and antimicrobial properties. The purpose of this study was the phytochemical analysis of M. oleifera and the identification of the antimicrobial compounds by combining a chemical approach with in vitro tests. The metabolite profile of M. oleifera polar and apolar extracts of leaves and seeds were investigated by using Nuclear Magnetic Resonance spectroscopy and Gas Chromatography-Mass Spectrometry. The antimicrobial activity of all of the obtained extract was evaluated against four bacterial pathogens (Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa and Salmonella enterica). The chemical analysis provided a wide set of metabolites that were identified and quantified. Moreover, apolar extracts from seeds showed a significant concentration-dependent antimicrobial activity against S. aureus and S. epidermidis, (4 mg/mL reduced the viability up to 50%) that was associated to the content of specific fatty acids. Our results remarked the advantages of an integrated approach for the identification of plant metabolites and its use in association with biological tests to recognize the compounds responsible for bioactivity without compounds purification. 相似文献
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65.
Monoalkylation of natural dihydroxycoumarins was carried out by Mitsunobu dehydroalkylation under sonochemical conditions. Aesculetin (6,7-dihydroxycoumarin) was selectively alkylated in good yield with prenyl alcohols at position 7, as clearly shown by NOESY experiments; though less selectively, position 7 was also the most reactive in daphnetin (7,8-dihydroxycoumarin). The synthesis of the phytoestrogen ferujol is also reported for the first time. 相似文献
66.
Ab initio SCF and Cl calculations are reported for ground and various low-lying Rydberg and valence excited states of thioformaldehyde H2CS. A double-zeta basis of near Hartree-Fock quality is employed in this work and the importance of polarization functions is also assessed. The calculations indicate uniformly larger CX bond lengths in this system than for H2CO in the corresponding electronic states; they also lind potential minima for H2CS non-planar nuclear conformations in the (n,π*) and (π,π*) excited states but in each case the calculated inversion barriers are seen to be smaller than those encountered in formaldehyde. The vertical transition energies to the various excited states studied are also found to be significantly smaller in H2CS than in H2CO but the order of electronic states is concluded to be virtually identical for the two systems. The lowest-lying excited states are the 3,1(n,π*) species calculated at 1.84 and 2.17 eV respectively; the first two allowed transitions are indicated to be the Rydberg species (n,sR) and (n,pxR) at 5.83 and 6.62 eV. These are followed by the two allowed transitions σ → π* and π → π* at 7.51 and 7.92 eV respectively, both well below the first ionization limit in H2CS. The much smaller splitting between the 3,1(π,π*) species in H2CS than in H2CO is attributed to the relatively diffuse charge distribution of the sulfur atom compared to that of oxygen. 相似文献
67.
Bruna Bovio
Sandro Calogero
Friedrich E. Wagner
Alfredo Burini
Bianca Rosa Pietroni 《Journal of organometallic chemistry》1994,470(1-2):275-283Reactions of the trinuclear [Au3Rim3] compound (Rim = [μ-1-benzylimidazolato-N3,C2] with several reagents capable of oxidative addition have been investigated by 197Au Mössbauer spectroscopy. The reaction products are either AuI carbene mononuclear and binuclear complexes or trinuclear AuIII and mixed-valence compounds. The X-ray crystal structure of the mixed-valence complex [AuIIIAuI2Rim3I2] has been determined. Two two-coordinate AuI centres show average Au---C and Au---N distances of 2.02(3) and 2.04(2) Å and average C---Au---N angles of 175.0(1.2)°, whereas the four-coordinate AuIII centre gives Au---C and Au---N 1.96(4) and 1.91(3) Å with the C---Au---N angle 170.5(1.6)°, and Au---I average distances 2.598(3) Å, with an I---Au=I angle 175.8(1)°. The Au---Au intramolecular distances [Au(1) Au(2) 3.432(3), Au(1) Au(3) 3.508(3), Au(2) Au(3) 3.464(3) Å] indicate a weak metal-metal interaction. 相似文献
68.
Daniel F. Kawano Bruna Z. Costa Katherine L. Romero-Orejn Hugo C. Loureiro Dosil P. de Jesus Anita J. Marsaioli 《Molecules (Basel, Switzerland)》2021,26(9)
1-Pyrrolines are important intermediates of active natural products, such as the 2,5-dialkyl-1-pyrroline derivatives found in fire ant venoms. Here, 5-hexyl-2-methyl-3,4-dihydro-2H-pyrrole was synthesized by the enzymatic transamination/cyclization of 2,5-undecadione, and enantiodifferenciation was successfully achieved by capillary electrophoresis with sulfobutyl ether--cyclodextrin as the chiral selector. The rationale of the enantiomeric discrimination was based on the results of a docking simulation that revealed the higher affinity of (S)-5-hexyl-2-methyl-3,4-dihydro-2H-pyrrole for the sulfobutyl ether--cyclodextrin. 相似文献
69.
Sunto Si caratterizzano le masse non continue e non atomiche, definite su un campo di insiemi e le masse definite su un -campoA che verificano la proprietá: (A T(A)) è chiuso, per ogni A A. Si dà inoltre, per tali masse, la struttura di (A T(A)), provando che tale insieme numerico è simile al codominio di una misura limitata.
Research supported by M.P.I. and C.N.R. 相似文献
Research supported by M.P.I. and C.N.R. 相似文献
70.
Zinellu A Sotgia S Galistu F Lumbau F Pasciu V Mario Pes G Tadolini B Deiana L Carru C 《Talanta》2004,64(2):428-434
The aim of this work is the application of Stocks and Miller capillary electrophoresis (CE) method in order to evaluate the human LDL susceptibility to Cu2+-induced oxidation. Lipid peroxidation determines a change in the relative electrophoretic mobility (REM) of lipoprotein that can be monitored by capillary electrophoresis using uncoated fused silica capillaries and tricine-methylglucamine as electrophoretic buffer.We have evaluated the differences in the susceptibility to oxidation of LDL subjected to different preparations (dialysis or gel filtration, after ultracentrifugation, to remove EDTA), and different storage (4 °C for 1 week or lyophilization) by measuring REM and lipid hydroperoxides (ROOH) with a spectrophotometer assay. Our results indicate that gel filtration is a more convenient procedure than dialysis for the isolation of LDL and that lyophilised samples are less prone to oxidation than those stored at 4 °C. Moreover, REM appears to be a more sensitive and easier method than spectrophotometer assay both to monitor the oxidative modification of LDL and to evaluate oxidative state of native LDL. 相似文献