查找使用阿拉丁产品的科研文献

Antisolvent sequence as a tunable switch for zein-naringin-D-tocopheryl polyethylene glycol 1000 succinate (TPGS) nanoparticles: interfacial dynamics and bioactivity enhancement

Yitong Wang,Keyu Qiu,Ruizi Zhou,Shuxian Bai,Chao Ai,Yanan Zhao,Jesus Simal-Gandara,Hui Teng,Lei Chen

Naringin (NRG), despite their demonstrated health benefits as natural bioactive compounds, are hampered by intrinsic hydrophobicity, which consequently impedes processability in aqueous systems and severely constrains oral bioavailability. The aim of this study was to form different type nanoparticles by Zein, TPGS and NRG, nanoparticles were obtained by the anti-solvent method, and to analyze the internal interaction forces, stability and antioxidative. The sequence of the antisolvents used becomes the primary factor influencing the properties of the nanoparticles. Nanoparticles were characterized by multimodal analysis, as spectroscopy, molecular docking, SEM, XRD, FTIR, TGA, and ITC. NRG is stabilized within the Zein matrix through hydrogen bonding involving Gln residues and hydroxyl or carbonyl groups, coupled with hydrophobic sequestration of its aglycone moiety in Pro-rich nonpolar cavities. The encapsulation efficiency of NRG increased up to 72.71 % at ( Z -N)-T, which is the highest stability among different types of nanoparticles. The nanoparticles average size below 105 nm, and the zeta potential is 25.48 mV, and also exhibits significant antioxidant activity. This study architected Zein-based nanoparticles to methodically assess the interaction force and stability, pioneering a formulation approach for engineered carriers in food and drug delivery matrices.

Luminescence Enhancement of CsMnBr3 Nanocrystals through Heterometallic Doping

Yacong Li,Chuying Wang,Guangyong Xu,Guigen Luo,Zhengtao Deng

The absorption and photoluminescence (PL) of CsMnBr3 with Mn(II) in octahedral crystal fields are extremely weak due to a d–d forbidden transition. Herein, we introduce a facile and general synthetic procedure that can prepare undoped and heterometallic doped CsMnBr3 NCs at room temperature. Importantly, both PL and absorption of CsMnBr3 NCs were significantly improved after doping a small amount of Pb2+ (4.9%). The absolute photoluminescence quantum yield (PL QY) of Pb-doped CsMnBr3 NCs is up to 41.5%, 11-fold higher than undoped CsMnBr3 NCs (3.7%). The PL enhancement is attributed to the synergistic effects between [MnBr6]4– units and [PbBr6]4– units. Furthermore, we verified the similar synergistic effects between [MnBr6]4– units and [SbBr6]4– units in Sb-doped CsMnBr3 NCs. Our results highlight the potential of tailoring luminescence properties of manganese halides through heterometallic doping.

High-stability, low-power and broadband-spectral-response flexible carbon nanotube photoelectronic synaptic transistors modified with D-π-A-π-D photosensitive molecules

Mingnan Chen,Kaixiang Kang,Zheng Chen,Nianzi Sui,Shuangshuang Shao,Min Li,Siyi Zhu,Wanzhen Xu,Jianwen Zhao

The development of neuromorphic optoelectronic devices with broadband response, low power consumption and high stability has emerged as a prominent research focus due to their potential application in artificial intelligence. Hence, we report a flexible carbon nanotube-based photoelectronic synaptic transistor array modified by a D-π-A-π-D structured photosensitive molecule, 4,8-diyldi-5,2-thiophenediylbis[4-(N,N-bis(4-octyloxyphenyl)amino)phenyl]benzo[1,2-c:4,5-c']bis([1,2,5]thiadiazole) (PM329), in the device channels. The incorporation of PM329 into single-walled carbon nanotube (SWCNT) channels enables broadband photoresponse ranging from 365 nm to 1050 nm, alongside outstanding device performance, including high stability (operational after two months of air storage), resistance to water and oxygen interference, long retention times (78.50 % of the current retained after 10000 s during slow relaxation) and ultralow power consumption (as low as 25 aJ per event). These properties are attributed to the precise energy band alignment between PM329 and SWCNTs, facilitating efficient charge transport and enhanced photoresponse. Furthermore, the neuromorphic devices exhibit critical synaptic behaviors, including excitatory postsynaptic currents (EPSC), short-term potentiation (STP), long-term potentiation (LTP) and paired-pulse facilitation (PPF). Key functionalities such as image perception, associative learning and long-term memory were successfully demonstrated under pulsed light stimulation. Notably, when integrated into a machine vision system, the transistor arrays enable automobile rear-end collision detection and image perception capabilities. This work highlights a robust and scalable strategy for developing carbon-based optoelectronic synaptic devices with high stability, energy efficiency and practical applicability, offering significant potential for artificial intelligence and neuromorphic computing.

D-Amino acids inhibit initial bacterial Adhesion: Thermodynamic evidence

Su-Fang Xing,Xue-Fei Sun,Alicia A. Taylor,Sharon L. Walker,Yi-Fu Wang,Shu-Guang Wang

Bacterial biofilms are structured communities of cells enclosed in a self-produced hydrated polymeric matrix that can adhere to inert or living surfaces. D-Amino acids were previously identified as self-produced compounds that mediate biofilm disassembly by causing the release of the protein component of the polymeric matrix. However, whether exogenous D-amino acids could inhibit initial bacterial adhesion is still unknown. Here, the effect of the exogenous amino acid D-tyrosine on initial bacterial adhesion was determined by combined use of chemical analysis, force spectroscopic measurement, and theoretical predictions. The surface thermodynamic theory demonstrated that the total interaction energy increased with more D-tyrosine, and the contribution of Lewis acid–base interactions relative to the change in the total interaction energy was much greater than the overall nonspecific interactions. Finally, atomic force microscopy analysis implied that the hydrogen bond numbers and adhesion forces decreased with the increase in D-tyrosine concentrations. D-Tyrosine contributed to the repulsive nature of the cell and ultimately led to the inhibition of bacterial adhesion. This study provides a new way to regulate biofilm formation by manipulating the contents of D-amino acids in natural or engineered systems. Biotechnol. Bioeng. 2015;112: 696–704. © 2014 Wiley Periodicals, Inc.

Prebiotic Absolute Asymmetric Synthesis of d‐Ribose on Wollastonite

Wendi Zhang,Yang Gao,Jiao Wang,Quanzheng Deng,Lu Han,Wanning Zhang,Yuxi Fang

ATP is the core substance of energy metabolism in all forms of life. The chirality of d ‐ribose is essential for ATP's function, ensuring efficient molecular recognition, metabolic stability, and co‐evolution with RNA in biological processes. However, origin of chirality of d ‐ribose is still unknown. Here, we demonstrate that wollastonite, an abundant Earth mineral, catalyzes the formose reaction between formaldehyde and glycolaldehyde and achieves high enantioselectivity (63.3%–91.3% ee ) toward d ‐ribose. The lower energy barrier for the transition state of d ‐glyceraldehyde compared to that of l ‐glyceraldehyde, which possesses a similar configuration to glyceraldehyde, results in the enantioselective synthesis of ribose. Experimental and computational studies reveal that the surface chirality of wollastonite, which is characterized by its wavy atomic arrangement, selectively reduces the adsorption energy of the d ‐glyceraldehyde intermediate compared to its l ‐enantiomer. This preferential adsorption kinetically promotes the d ‐glyceraldehyde pathway and steers the reaction toward d ‐ribose. Our work establishes wollastonite as an intrinsically enantioselective mineral catalyst, provides a mechanistic foundation for prebiotic chiral selection toward d ‐ribose, and highlights surface design principles for asymmetric synthesis. Wollastonite's inherent surface chirality lowers the energy barrier for d ‐glyceraldehyde, kinetically favoring its pathway over l ‐forms. This preferential adsorption steers the formose reaction toward d ‐ribose, offering a prebiotic mechanism for chiral selection.

Yeast phospholipase D, Spo14, is not required for macroautophagy

Yun Chen,Zulin Wu,Lin Dong,Xia You,Yanling Ji,Yongheng Liang

Autophagy-related gene (Atg) proteins are key players in autophagy. Some proteins that function in vesicle trafficking and lipid metabolism are also involved in autophagy. The SPO14 in yeast, which encodes phospholipase D (PLD), is involved in membrane trafficking and plays a vital role in sporulation during meiosis. Crosstalk has been identified between autophagy and sporulation. Although the PLD is required for macroautophagy in mammals, its role in yeast macroautophagy remains unclear. We observed that Spo14 is not required for macroautophagy in yeast and that it is dispensable for Atg8 lipidation, which plays an important role in phagophore extension. Our results also revealed that green fluorescent protein (GFP)-Atg8 degradation is not completely blocked in atg1 Δ/ atg1 Δ cells under sporulation condition. Therefore, Spo14 is not required for macroautophagy in yeast. Take away Yeast phospholipase D, Spo14, is dispensable for macroautophagy in haploid and diploid cells. The essential role of Spo14 in sporulation in diploid yeast cells is not associated with macroautophagy. The unique distribution of fluorescent proteins in WT/WT tetrads in a sporulation medium is not autofluorescence.

Molecular engineering of the fused azacycle donors in the D-A-π-A metal-free organic dyes for efficient dye-sensitized solar cells

Ke Cai,Hanlun Wu,Tao Hua,Chaoqiang Liao,Hao Tang,Lingyun Wang,Derong Cao

Four novel D-A-π-A metal-free organic sensitizers QL1 – 4 with the fused azacycle units as donors have been designed and synthesized to investigate the relationship between both the sizes and conjugations of azacycle and performances of dye-sensitized solar cells systematically. QL1 with the five-membered azacycle, i.e., with carbazole ( Cz ) as donor, exhibits the smallest molar extinction coefficients ( ε ). QL2 and QL3 with the seven-membered azacycle, i.e. with N -phenyl-iminostilbene ( ISB ) and N -phenyl-iminodibenzyl ( IDB ) as donors, respectively, show the red-shifted absorption spectra and higher ε compared to QL1 . However, QL2 and QL3 with an only distinction in a single or double bond, display distinctive PCEs. QL4 with the six-membered azacycle, i.e., 9,9,10-triphenyl-9,10-dihydroacridine ( TDD ), exhibits a blue-shifted absorption spectrum due to a big dihedral angle , resulting in a lower photovoltaic performance . Especially, QL3 with the ISB donor is conducive to achieving a PCE of 6.22%, which is higher than QL2 , due to its better planar structure and more conjugation. When co-adsorbed with CDCA, QL3 exhibits the highest PCE of 7.14% among all dyes, and up to 8.26% by co-sensitizing with dye WL5 , which surpasses that of the reference dye N719 (7.75%). The results indicate that the size and conjugation of the fused azacycle donors may affect the photovoltaic performance significantly, and the ISB unit is demonstrated as a promising donor for efficient organic dyes.

A Hybrid Process for Valorization of d-Fructose to 2,5-Bis(hydroxymethyl)furan by Bridging Chemocatalysis and Biocatalysis in a Betaine:Benzenesulfonic Acid System

Yu Peng,Luyao Jiang,Junhua Di,Cuiluan Ma,Qi Li,Yucai He

Biobased 2,5-bis(hydroxymethyl)furan is a versatile building block for the production of drugs, polymers, crown ethers, bioactive compounds, and value-added intermediates. To explore a more efficient route to synthesize 2,5-bis(hydroxymethyl)furan, a tandem transformation by quick dehydration with a deep eutectic solvent betaine:benzenesulfonic acid (Bet:BSA) and mild bioreduction with recombinant Escherichia coli (E. coli) DCF was developed for converting d-fructose into 2,5-bis(hydroxymethyl)furan. The 5-hydroxymethylfurfural yield reached 62.3 ± 1.6% (based on d-fructose) in Bet:BSA at 120 °C after a short time (2 min). d-Fructose-valorized 5-hydroxymethylfurfural was biologically transformed to 2,5-bis(hydroxymethyl)furan by newly constructed recombinant E. coli DCF containing reductase and formate dehydrogenase at 40 °C and pH 7.5 after 48 h, with a yield of 99.6 ± 0.1% (based on 5-hydroxymethylfurfural) in Bet:BSA-water containing the cosubstrate HCOONa (5-HMF-to-HCOONa molar ratio, 1:2.5). Meanwhile, 150 mM commercial 5-hydroxymethylfurfural was transformed into 2,5-bis(hydroxymethyl)furan in a yield of 94.4 ± 0.9%. An efficient hybrid process was constructed to valorize d-fructose to 2,5-bis(hydroxymethyl)furan in Bet:BSA-water, which has good industrial application potential.

Characterization of a novel lipase from Bacillus licheniformis NCU CS-5 for applications in detergent industry and biodegradation of 2,4-D butyl ester

Junxin Zhao,Shichang Liu,Yifang Gao,Maomao Ma,Xianghui Yan,Ding Cheng,Dongman Wan,Zheling Zeng,Ping Yu,Deming Gong

Enzymatic degradation has become the most promising approach to degrading organic ester compounds. In this study, Bacillus licheniformis NCU CS-5 was isolated from the spoilage of Cinnamomum camphora seed kernel, and its extracellular lipase was purified, with a specific activity of 192.98 U/mg. The lipase was found to be a trimeric protein as it showed a single band of 27 kDa in SDS-PAGE and 81 kDa in Native-PAGE. It was active in a wide range of temperatures (5–55 °C) and pH values (6.0–9.0), and the optimal temperature and pH value were 40 °C and 8.0, respectively. The enzyme was active in the presence of various organic solvents, metal ions, inhibitors and surfactants. Both crude and purified lipase retained more than 80% activity after 5 h in the presence of commercial detergents, suggesting its great application potential in detergent industry. The highest activity was found to be towards medium- and long-chain fatty acids (C 6 -C 18 ). Peptide mass spectrometric analysis of the purified lipase showed similarity to the lipase family of B. licheniformis . Furthermore, it degraded more than 90% 2,4-D butyl ester to its hydrolysate 2,4-D within 24 h, indicating that the novel lipase may be applied to degrade organic ester pesticides.

Two-stage biosynthesis of D-tagatose from milk whey powder by an engineered Escherichia coli strain expressing L-arabinose isomerase from Lactobacillus plantarum

Guoyan Zhang,Hossain M. Zabed,Junhua Yun,Jiao Yuan,Yufei Zhang,Yang Wang,Xianghui Qi

In this study, a new strain of Lactobacillus plantarum (CY.6) was identified and its L-arabinose isomerase (L-AI) encoding gene ( ara A) was overexpressed in Escherichia coli BL21 for the biosynthesis of D-tagatose from milk whey powders (WP). Whole-cell biotransformation of lactose in WP into D-tagatose was done by three technological approaches, including 100%, 50% and 0% hydrolysis of lactose in WP before biotransformation, where simultaneous saccharification and biotransformation (SSB, 0% prior hydrolysis of lactose) produced maximum amounts of D-tagatose. Two-stage SSB provided 73.6% conversion efficiency (based on D-galactose) and 36.8% (in term of lactose), with 51.5 g/L of D-tagatose after 96 h, while concentration of D-tagatose produced after first stage was 34.4 g/L. Yield and volumetric productivity of D-tagatose after two-stage SSB were found to be 0.26 g/g of WP (0.37 g/g of lactose, 0.74 g/g of D-galactose produced from lactose) and 0.54 g/L/h, respectively.

In vitro and in vivo evaluation of redox-responsive sorafenib carrier nanomicelles synthesized from poly (acryic acid) -cystamine hydrochloride-D-α-tocopherol succinate

Yu Liu,Jia Yang,Xin Wang,Ju Liu,Zhaobo Wang,Hongsheng Liu,Lijiang Chen

Enhanced Thermostability of an Improved l-Arabinose Isomerase Mutant for d-Tagatose Synthesis by Molecular Dynamics Simulations-Guided Rational Redesign of Flexible Regions

Yuvaraj Ravikumar,Abdullah Arsalan,Xinrui Tang,Guoyan Zhang,Xianghui Qi

l-Arabinose isomerase (l-AI) catalyzes d-galactose to produce the rare, industrially important sugar d-tagatose. Enzyme stability is vital for its application in industrial processes, and rational design-based protein engineering methods have been employed to improve its stability. This study employed molecular dynamics simulations (MDS)-guided rational redesign of flexible regions to improve the thermostability of mesophilic Bifidobacterium adolescentis l-AI (Ba-l-AI). Comparative MDS (200 ns, 340–360 K) of thermophilic l-AIs (Geobacillus kaustophilus Gk-l-AI and Thermotoga maritima Tm-l-AI) and mesophilic Ba-l-AI identified flexible regions in Ba-l-AI via RMSF and ionic interaction. Five stabilizing mutations (G78C, K46R, N187R, K112R, and N190R) were introduced to provide rigidness. MDS of the mutant revealed reduced RMSF/RMSD, improved compactness, and enhanced conformational stability across temperatures, supported by free-energy landscape analysis resembling thermophilic profiles. Experimentally, the mutant exhibited superior thermal stability (72 °C), broader pH/temperature tolerance, and efficient d-tagatose production. The redesigned Ba-l-AI’s rigid backbone and stability highlight its potential for industrial d-tagatose biosynthesis.