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31.
Rim Nasri Mourad Jridi Imen Lassoued Ines Jemil Rabeb Ben Slama-Ben Salem Moncef Nasri Maha Karra-Châabouni 《Applied biochemistry and biotechnology》2014,173(5):1121-1134
Antioxidant properties and angiotensin-converting enzyme (ACE) inhibitory activities of protein hydrolysates from goby (Zosterisessor ophiocephalus) muscle, with different degrees of hydrolysis (DH) from 5 to 25 %, prepared by treatment with crude proteases extract from smooth hound intestines, were investigated. Goby protein hydrolysates (GPHs) are rich in Gly and Thr, which accounted for 14.1–15 % and 11.6–13.2 % of the total amino acids, respectively. The antioxidant activities of GPHs were investigated by using several in vitro assay systems. All GPHs exhibited significant metal chelating activity and DPPH free radical-scavenging activity, and inhibited linoleic acid peroxidation. For the ACE-inhibitory activity, as the DH increased, the activity of GPHs increased. The obtained results revealed that antioxidant and ACE-inhibitory activities of GPHs were influenced by the degree of hydrolysis. A medium degree of enzymatic hydrolysis was appropriate to obtain GPHs with good antioxidant activity, while small peptides were essential to obtain high ACE inhibitory activity. 相似文献
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A methodology is reported for the regioselective nitration of the phenyl groups of Halterman porphyrin, using NaNO2. These nitro-porphyrins can be reduced to aminoporphyrins and then N-dimethylated to give new optically active porphyrins. Applications to the asymmetric epoxidation of styrene derivatives by H2O2 to give optically active epoxides (ee up to 60%) and hydroxylation of alkanes to give optically active secondary alcohols (ee up to 69%) were carried out in organic solvents (dichloromethane/methanol) using chiral iron and manganese porphyrins as catalysts. 相似文献
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Over the last decays, the use of conductive biopolymer composites has been growing in areas such as biosensors, soft robotics, and wound dressing applications. They are generally soft hydrophilic materials with good elastic recovery and compatible with biological environments. However, their application and removal from the host are still challenging mainly due to poor mechanical strength. This work displays a technique for the fabrication of complex‐shaped conductive structures with improved mechanical strength by wet three‐dimensional (3‐D) printing, which uses a coagulation bath to quickly solidify an epoxy cross‐linked chitosan/carbon microtube composite ink. The fabricated conductive structure demonstrated higher elongation strength and improved elastic stability upon the introducing of polypropylene glycol diglycidyl ether (PPGDGE) as the epoxy cross‐linker, which can be due to the formation of networks between oxiran groups of PPGDGE and chitosan amino groups. 相似文献
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A facile and diastereoselective synthetic procedure has been designed for the preparation of new substituted indolo[2,3-b]indole (IDID) moiety at position-5 of the pyrimidine ring by a one-pot four-component reaction of dimedone, aniline and substituted derivatives, barbituric acid/thiobarbituric acid and isatin under mild conditions. This method proceeds rely on a CsbndN bond formation under catalyst-free conditions affording a range of skeletally diversity 5-indolo[3,2-b]indole-pyrimidine-based heterocycles. 5-Indolo[2,3-b]indol-pyrimidine-2,4,6-trione and 5-indolo[2,3-b]indol-2-thioxo-pyrimidine-4,6-dione were obtained in EtOH solvent in high yield, short reaction time and diastereoselectivity. The structural diversities of the synthesized compounds have been confirmed spectroscopically, by IR 1H- and 13C NMR, EI-MS spectra and elemental analyses which agree with the proposed structures. 相似文献
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Mouhieddinne Guergueb Frdrique Loiseau Florian Molton Habib Nasri Axel Klein 《Molecules (Basel, Switzerland)》2022,27(5)
The meso-tetrakis(4-(trifluoromethyl)phenyl)porphyrinato cobalt(II) complex [Co(TMFPP)] was synthesised in 93% yield. The compound was studied by 1H NMR, UV-visible absorption, and photoluminescence spectroscopy. The optical band gap Eg was calculated to 2.15 eV using the Tauc plot method and a semiconducting character is suggested. Cyclic voltammetry showed two fully reversible reduction waves at E1/2 = −0.91 V and E1/2 = −2.05 V vs. SCE and reversible oxidations at 0.30 V and 0.98 V representing both metal-centred (Co(0)/Co(I)/Co(II)/Co(III)) and porphyrin-centred (Por2−/Por−) processes. [Co(TMFPP)] is a very active catalyst for the electrochemical formation of H2 from DMF/acetic acid, with a Faradaic Efficiency (FE) of 85%, and also catalysed the reduction of CO2 to CO with a FE of 90%. Moreover, the two triarylmethane dyes crystal violet and malachite green were decomposed using H2O2 and [Co(TMFPP)] as catalyst with an efficiency of more than 85% in one batch. 相似文献
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Dr. Zahra Nasri Seyedali Memari Sebastian Wenske Ramona Clemen Dr. Ulrike Martens Prof. Mihaela Delcea Dr. Sander Bekeschus Prof. Klaus-Dieter Weltmann Prof. Thomas von Woedtke Dr. Kristian Wende 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(59):14702-14710
Several studies have revealed that various diseases such as cancer have been associated with elevated phospholipase A2 (PLA2) activity. Therefore, the regulation of PLA2 catalytic activity is undoubtedly vital. In this study, effective inactivation of PLA2 due to reactive species produced from cold physical plasma as a source to model oxidative stress is reported. We found singlet oxygen to be the most relevant active agent in PLA2 inhibition. A more detailed analysis of the plasma-treated PLA2 identified tryptophan 128 as a hot spot, rich in double oxidation. The significant dioxidation of this interfacial tryptophan resulted in an N-formylkynurenine product via the oxidative opening of the tryptophan indole ring. Molecular dynamics simulation indicated that the efficient interactions between the tryptophan residue and phospholipids are eliminated following tryptophan dioxidation. As interfacial tryptophan residues are predominantly involved in the attaching of membrane enzymes to the bilayers, tryptophan dioxidation and indole ring opening leads to the loss of essential interactions for enzyme binding and, consequently, enzyme inactivation. 相似文献
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Tewari BB Shekar S Huang L Gorrell CE Murphy TP Warren K Nesnas N Wehmschulte RJ 《Inorganic chemistry》2006,45(21):8807-8811
Aluminumoxyhydride (HAlO) has been obtained by the reaction of aluminum hydride with the siloxane (Me2HSi)2O or the stannoxane (Bu3Sn)2O as an amorphous colorless insoluble powder. The highest-purity product resulted from the reaction of H3Al.NMe3 with (Me2HSi)2O. However, HAlO suspensions in tetrahydrofuran (THF) of sufficient quality for synthetic applications can be prepared from commercially available reagents with only minor precautions. A LiAlH4 solution in THF was treated successively with Me3SiCl and (Me2HSi)2O, followed by heating at 60 degrees C for 20 h. The resulting suspensions are 0.4-0.5 M in active hydride content and selectively reduce aldehydes and ketones to the respective alcohols in the presence of any other common nonprotic functional group. 相似文献
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We present a new mechanism for generating the baryon asymmetry of the Universe directly in the decay of a singlet scalar field S(r) with a weak scale mass and a high dimensional baryon number-violating coupling. Unlike most currently popular models, this mechanism, which becomes effective after the electroweak phase transition, does not rely on the sphalerons for inducing a nonzero baryon number. CP asymmetry in S(r) decay arises through loop diagrams involving the exchange of W+/- gauge bosons and is suppressed by light quark masses, leading naturally to a value of eta(B) approximately 10(-10). The simplest realization of this idea which uses a six quark DeltaB=2 operator predicts colored scalars accessible to the CERN Large Hadron Collider and neutron-antineutron oscillation within reach of the next-generation experiments. 相似文献