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81.
Bao-Hong Lee Wei-Hsuan Hsu Chih-Yao Hou Hao-Yuan Chien She-Ching Wu 《Molecules (Basel, Switzerland)》2021,26(12)
Mango peels are usually discarded as waste; however, they contain phytochemicals and could provide functional properties to food and promote human health. This study aimed to determine the optimal lactic acid bacteria for fermentation of mango peel and evaluate the effect of mango peel on neuronal protection in Neuron-2A cells against amyloid beta (Aβ) treatment (50 μM). Mango peel can be fermented by different lactic acid bacteria species. Lactobacillus acidophilus (BCRC14079)-fermented mango peel produced the highest concentration of lactic acid bacteria (exceeding 108 CFU/mL). Mango peel and fermented mango peel extracts upregulated brain-derived neurotrophic factor (BDNF) expression for 1.74-fold in Neuron-2A cells. Furthermore, mango peel fermented products attenuated oxidative stress in Aβ-treated neural cells by 27%. Extracts of L. acidophilus (BCRC14079)-fermented mango peel treatment decreased Aβ accumulation and attenuated the increase of subG1 caused by Aβ induction in Neuron-2A cells. In conclusion, L. acidophilus (BCRC14079)-fermented mango peel acts as a novel neuronal protective product by inhibiting oxidative stress and increasing BDNF expression in neural cells. 相似文献
82.
Shicheng Hou Shishao Liang Chao Zhang Yingmei Han Jianhui Liang Hongyu Hu Xingeng Zhang Chun Hu Xiaoping Liu Hong Zhang 《Molecules (Basel, Switzerland)》2021,26(12)
The development of cancer treatments requires continuous exploration and improvement, in which the discovery of new drugs for the treatment of cancer is still an important pathway. In this study, based on the molecular hybridization strategy, a new structural framework with an N-aryl-N’-arylmethylurea scaffold was designed, and 16 new target compounds were synthesized and evaluated for their antiproliferative activities against four different cancer cell lines A549, MCF7, HCT116, PC3, and human liver normal cell line HL7702. The results have shown seven compounds with 1-methylpiperidin-4-yl groups having excellent activities against all four cancer cell lines, and they exhibited scarcely any activities against HL7702. Among them, compound 9b and 9d showed greatly excellent activity against the four kinds of cells, and the IC50 for MCF7 and PC3 cell lines were even less than 3 μM. 相似文献
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In this paper, we presented a novel, rapid and highly sensitive sensor for glutathione (GSH), cysteine (Cys) and histidine (His) based on the recovered fluorescence of the carbon quantum dots (CQDs)–Hg(II) system. The CQDs were synthesized by microwave-assisted approach in one pot according to our previous report. The fluorescence of CQDs could be quenched in the presence of Hg(II) due to the coordination occurring between Hg(II) and functional groups on the surface of CQDs. Subsequently, the fluorescence of the CQDs–Hg(II) system was recovered gradually with the addition of GSH, Cys or His due to their stronger affinity with Hg(II). A good linear relationship was obtained from 0.10 to 20 μmol L−1 for GSH, from 0.20 to 45 μmol L−1 for Cys and from 0.50 to 60 μmol L−1 for His, respectively. This method has been successfully applied to the trace detection of GSH, Cys or His in human serum samples with satisfactory results. The proposed method was simple in design and fast in operation, which demonstrated great potential in bio-sensing fields. 相似文献
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Structures and Fluorescent Properties of Cadmium(II) Complexes with 1D and 2D Structures Based on Tridentate Benzimidazole Ligands 下载免费PDF全文
The cadmium(II) complexes [CdL1(m‐nba)2] ( 1 ), [CdL1(p‐nba)2] · C2H5OH ( 2 ), [CdL2(p‐nba)2] · CH3OH ( 3 ), and [CdL2(p‐nbat)2] ( 4 ) containing the ligands L1 and L2 [L1 = 2,6‐bis(benzimidazol‐2‐yl)pyridine, L2 = bis(2‐benzimidazolylmethyl)amine] were synthesized and characterized (m‐nba, p‐nba, and p‐nbat are the anions of p‐nitrobenzoic acid, m‐nitrobenzoic acid, and p‐nitrobenzeneacetic acid, respectively). The complexes were investigated by X‐ray single crystal diffraction, elemental analysis as well as IR and fluorescence spectroscopy. Compounds 1 – 3 contain a distorted pentagonal bipyramidal coordination sphere with CdII coordinated by two carboxylate ligands in bidentate‐chelating mode, whereas complex 4 exhibits a distorted octahedral arrangement with one carboxylate ligand in bidentate‐chelating and the other in monodentate coordination mode. 1 and 2 form a 1D chain interplayed by hydrogen bonding and strong π–π stacking interactions. 3 and 4 vary from 1D chain into 2D single‐layer and double‐layer networks because of more extensive hydrogen bonding interactions. The complexes show emission maxima in the blue region in the solid state and emission bands are red‐shifted compared to those of the free ligands. 相似文献
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From orientation disordered to ordered—An ab initio simulation on ammonia borane phase transition within van der Waals corrections 下载免费PDF全文
Qi Song Zhenyi Jiang Zhiyong Zhang Yuqing Hou Xiaodong Zhang 《Journal of computational chemistry》2015,36(1):22-32
In this work, we report a detailed theoretical investigation of the phase transition of ammonia borane (NH3BH3; AB), from a tetragonal I4mm ( ) phase with disordered orientation of hydrogen to an orthorhombic phase with Pmn21 ( ) symmetry, as a function of temperature based on Density Functional Theory calculations with semiempirical dispersion potential correction. We define a series of substructures with the NH3BH3 moiety always in C3v symmetry and the partially occupied high temperature state can be described as a continuous transformation between these substructures. To understand the role of the van der Waals corrections to the physical properties, we use the empirical Grimme's dispersion potential correction (PBE‐D2). Both Perdew–Burke–Emzerhof (PBE) and PBE‐D2 functional yield almost the same energy sequence along the transition path. However, PBE‐D2 functional shows obvious advantage in describing the lattice parameters of AB. The rigid rotor harmonic oscillator approximation is used to compute the free energy and the entropies contribution along the transition pathway. With knowledge of free energy surfaces along rotations of the ? [NH3] and ? [BH3] groups, complete transformation paths are mapped out. The phase transition is found to follow the sequence of partially occupied tetragonal system (I4mm) of a mixture of states with monoclinic (Cc), (CM) and orthorhombic (Pmn21) symmetries to fully occupied quasitetragonal system (the intermediate phase, Pmn21) to fully occupied orthorhombic system (Pmn21). © 2014 Wiley Periodicals, Inc. 相似文献