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991.
Hung-Yueh Chen Chang-Wei Hsieh Pin-Cheng Chen Shin-Pin Lin Ya-Fen Lin Kuan-Chen Cheng 《Molecules (Basel, Switzerland)》2021,26(18)
This study developed a nutritionally valuable product with bioactive activity that improves the quality of bread. Djulis (Chenopodium formosanum), a native plant of Taiwan, was fermented using 23 different lactic acid bacteria strains. Lactobacillus casei BCRC10697 was identified as the ideal strain for fermentation, as it lowered the pH value of samples to 4.6 and demonstrated proteolysis ability 1.88 times higher than controls after 24 h of fermentation. Response surface methodology was adopted to optimize the djulis fermentation conditions for trolox equivalent antioxidant capacity (TEAC). The optimal conditions were a temperature of 33.5 °C, fructose content of 7.7%, and dough yield of 332.8, which yielded a TEAC at 6.82 mmol/kg. A 63% increase in TEAC and 20% increase in DPPH were observed when compared with unfermented djulis. Subsequently, the fermented djulis was used in different proportions as a substitute for wheat flour to make bread. The total phenolic and flavonoid compounds were 4.23 mg GAE/g and 3.46 mg QE/g, marking respective increases of 18% and 40% when the djulis was added. Texture analysis revealed that adding djulis increased the hardness and chewiness of sourdough breads. It also extended their shelf life by approximately 2 days. Thus, adding djulis to sourdough can enhance the functionality of breads and may provide a potential basis for developing djulis-based functional food. 相似文献
992.
Huakuan Lin Shourong Zhu Appolin Bave Kondiano Xuncheng Su Fuping Kou Yunti Chen 《Polyhedron》1998,17(25-26)
The kinetics of the acid dissociation of copper(II) complexes of novel C-functionalized macrocyclic dioxotetraamines has been studied by means of a stopped-flow spectrophotometer. The acid dissociation rate follows the law Vd = CcomkK1K2H 2/(1+K1H+K1K2H 2). From the experimental facts we have obtained, the dissociation kinetics are interpreted by a mechanism involving the negatively charged carbonyl oxygen of the complex being rapidly protonated in a pre-equilibrium step, the rate-determining step being intramolecular hydrogen (enolic tautomer) migration (to imine nitrogen). The dissociation rate reached a plateau in the strongly acidic solution. By means of temperature coefficient method, ΔH φ, ΔS φ of the pre-equilibrium step and ΔH ≠, ΔS≠ of the rate-determining step were obtained. The results of 13-membered macrocyclic dioxotetraamines have been discussed. The influence of the substituents to the acid dissociation rates has also been discussed. The Bronsted type linear free energy relationships do also exist in these C-functionalized dioxotetraamine copper(II) complexes. 相似文献
993.
Development of subcellular organelle-targeted bioimaging probes is of great importance in the field of early detection of diseases and exploring the behaviors of subcellular organelles. Herein, we present a triphenylphosphonium functionalized conjugated macrocyclic tetramaleimide (TPP-CMT) as a mitochondrial-targeting bioimaging probe. The core of TPP-CMT is obtained by connecting two pyrenes and two benzenes through four maleimides. This unique structure endows TPP-CMT with exceptional far red/near-infrared aggregation-induced emission (FR/NIR-AIE) characteristics. TPP-CMT is an excellent fluorescent emitter in most solvents and even in solid states. The quantum yield of TPP-CMT was higher than 27% when dissolved in common middle-polarity organic solvent and this value remained at 28.2% in its solid state. The introduction of four triphenylphosphonium on maleimide positions endows TPP-CMT with mitochondrial-targeting ability. Thanks to the FR/NIR-AIE characteristics and the mitochondrial-targeting ability, this well-designed fluorescent probe was successfully employed for mitochondrial targeting bioimaging of HeLa and HepG2 cells. 相似文献
994.
Polymers are widely recognized to entail random conformations in good solvent governed by the need for achieving the highest entropy to reach thermodynamic equilibrium. In this context, it remains grand challenging to directly arrange them into ordered conformation as building blocks for further self-assembling into hierarchal structures. Herein, we report a simple yet viable strategy to progressively assemble rationally designed azobenzene-containing alternating copolymer(i.e., poly(binaphthyls... 相似文献
995.
Qing Dai Nongyue He Kuiping Weng Baoping Lin Zuhong Lu Chunwei Yuan 《Journal of inclusion phenomena and macrocyclic chemistry》1999,35(1-2):11-21
The photocatalytic activities of titanium dioxide (TiO2) supported on hexagonal mesoporous silica (HMS), zeolite Y (NaY) were investigated by using the photodegradation of 2,4,6-trichlorophenol (TCP) as test reactions. It was found that the photocatalytic activity of TiO2 on HMS was much higher than that of TiO2 powders, and that of TiO2 on NaY. It was also found that TiO2/HMS had maximal photocatalytic activity at a lower Ti content. The larger the pore size of HMS used as the support of TiO2, the better the photocatalytic activity of TiO2 for degradating of organic pollutant. These observations suggested that the supported structure was a main factor responsible for enhancement of the photocatalytic activity of TiO2. Characterization of the samples by TEM, XRD, BET, and UV-vis diffuse reflectance spectra indicated that the structures of HMS and TiO2 were confirmed and TiO2 did not enter into the HMS framework and was formed as nanoparticles on all supports. 相似文献
996.
Ab initio molecular orbital and hybrid density functional theory calculations have been performed to study the adsorption, isomerization, and decomposition of HCN on Si(100)-2×1 using the Si9H12 cluster model of the surface. The results of our calculations indicate that the HCN can adsorb molecularly without a barrier onto the surface with both end-on (LM1) and side-on (LM2) positions. LM1 can isomerize to LM2 with a small barrier of 8 kcal/mol. The isomerization of LM2 by H-migration from C to the N atom, requires 76 kcal/mol activation energy (c.f. 47.5 kcal/mol in the gas phase) because of surface stabilization. Both HCN(a) and HNC(a) end-on adsorbates were found to dissociate readily, as concluded in our earlier experiment, to produce H and CN adspecies. The computed vibrational frequencies of HCN, CN, and also HCNH adspecies agree reasonably well with those observed experimentally. HCNH was found to be stable, with either the C or the N attaching to the surface. 相似文献
997.
Xue Xie Jianming Zhou Lin Sun Hongda Zhang Yiwu Zhao Yaling Song 《Natural product research》2016,30(2):150-156
One new flavonol glycoside, 6-hydroxykaempferol-3-O-β-D-glucoside-7-O-β-D-glucuronide (1), together with eight known flavonoids and three known quinochalcones, was isolated from the florets of Carthamus tinctorius L. Their structures were determined by extensive spectroscopic analyses. Their cardioprotective effects against H2O2-induced apoptosis in H9c2 cells were also evaluated; compounds 1, 2, 4–5, 7–10 and 12 provided significant protective effects on H2O2-induced H9c2 cells at the concentration of 25 μg/mL. 相似文献
998.
Prof. Songping Wu Dr. Cuiping Han James Iocozzia Mingjia Lu Rongyun Ge Rui Xu Prof. Zhiqun Lin 《Angewandte Chemie (International ed. in English)》2016,55(28):7898-7922
Germanium‐based nanomaterials have emerged as important candidates for next‐generation energy‐storage devices owing to their unique chemical and physical properties. In this Review, we provide a review of the current state‐of‐the‐art in germanium‐based materials design, synthesis, processing, and application in battery technology. The most recent advances in the area of Ge‐based nanocomposite electrode materials and electrolytes for solid‐state batteries are summarized. The limitations of Ge‐based materials for energy‐storage applications are discussed, and potential research directions are also presented with an emphasis on commercial products and theoretical investigations. 相似文献
999.
A Single Excitation‐Duplexed Imaging Strategy for Profiling Cell Surface Protein‐Specific Glycoforms 下载免费PDF全文
Na Wu Lei Bao Prof. Dr. Lin Ding Prof. Dr. Huangxian Ju 《Angewandte Chemie (International ed. in English)》2016,55(17):5220-5224
This work develops a site‐specific duplexed luminescence resonance energy transfer system on cell surface for simultaneous imaging of two kinds of monosaccharides on a specific protein by single near‐infrared excitation. The single excitation‐duplexed imaging system utilizes aptamer modified upconversion luminescent nanoparticles as an energy donor to target the protein, and two fluorescent dye acceptors to tag two kinds of cell surface monosaccharides by a dual metabolic labeling technique. Upon excitation at 980 nm, only the dyes linked to protein‐specific glycans can be lit up by the donor by two parallel energy transfer processes, for in situ duplexed imaging of glycoforms on specific protein. Using MUC1 as the model, this strategy can visualize distinct glycoforms of MUC1 on various cell types and quantitatively track terminal monosaccharide pattern. This approach provides a versatile platform for profiling protein‐specific glycoforms, thus contributing to the study of the regulation mechanisms of protein functions by glycosylation. 相似文献
1000.
Shu‐Jin Li De‐Chun Zhang Zhong‐Lin Huang Yan‐Qiu Zhang Kai‐Bei Yu 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(9):1122-1123
In the cation of the title compound, C15H16NO+·C24H20B?, the pyridyl ring makes a dihedral angle of 14.03° with the phenyl ring. The anion has a slightly distorted tetrahedral geometry and forms honeycomb‐like sheets which extend along the b axis, forming channels containing the cations. A comparison of packing energies reveals a difference between the title compound and a similar material which has non‐linear optical properties. 相似文献