查找使用阿拉丁产品的科研文献

Spectroscopic and molecular dynamics investigation of dye-induced inhibition of α-amylase activity in yarn-dyed fabric

Xiaolong Cheng,Yifan Zhang,Na-won Baek,Xun Zhang,Wei Li

Yarn-dyed fabric (YDF) is increasingly utilized in the textile industry owing to its excellent color fastness and reduced environmental impact from dyeing effluent. However, YDF's enzyme desizing is hindered by leached dyes inhibiting α-amylase. As inhibition is dye-dependent, elucidating the competitive mechanism is crucial for optimizing efficiency and minimizing enzyme consumption. This study investigated the effect of direct yellow 50 (DY-50), reactive yellow-K (RY-K), methylene blue (MB) and indigo on α-amylase activity at varying concentrations. α-Amylase samples exposed to dyes were analyzed using Fourier transform infrared spectroscopy, ultraviolet-visible spectrophotometry (UV–Vis), intrinsic fluorescence spectroscopy, sulfhydryl group content determination, zeta potential and circular dichroism spectroscopy to elucidate structural alterations and the underlying inhibition mechanisms. The results indicated that all four dyes negatively impacted α-amylase activity via mixed competitive inhibition. DY-50 exhibited the most potent inhibitory effect on α-amylase, inducing a 25 % activity loss after 60 min of exposure. Comparatively, activity losses were milder with indigo (20.7 %), RY-K (15.9 %), and MB (10.6 %). Beyond inhibiting starch-enzyme contact, dye exposure induced structural changes in α-amylase, including altered hydrogen bonding, exposure of hydrophobic groups, decreased α-helix content (from 19.1 % to 15.9 %), and increased β-sheet content (from 29.5 % to 33.2 %), collectively contributing to the activity loss of α-amylase. Elucidating these inhibition mechanisms offers vital strategies to optimize α-amylase utilization in YDF desizing, thereby boosting enzymatic efficiency and industrial economics.

Hydrogen bonding-mediated α-Fe2O3-decorated rGO hybrids for dual-mode humidity sensing and multi-scenario applications

Bowen Zhang,Lulu Guo,Jiayue Xin,Guangrui Xiang,Shengxuan Xu,Yu Gong,Xiaohan Sun,LeTian Zhao,Ke Wu,Fan Li,Zhimin Yang

The development of self-powered humidity sensors featuring rapid response, low hysteresis, and dual-mode signal output is highly anticipated in healthcare monitoring, wearable electronics and human-machine interaction. Here, we present a hydrogen bonding-mediated self-assembly strategy to synthesize α-Fe 2 O 3 -decorated reduced graphene oxide (Fe 2 O 3 -rGO) hybrids for high-performance dual-mode humidity sensing. In impedance mode, the sensor demonstrates a broad detection range (11–98 % RH), a response value of 71.1 at 98 % RH, fast response/recovery times (1 s/5 s), and minimal hysteresis (3.7 %). The sensing mechanism, elucidated through complex impedance spectroscopy and water adsorption isotherms, reveals synergistic proton transport and p-n heterojunction effects at the α-Fe 2 O 3 -rGO interface. Notably, the sensor also operates in a self-powered mode, generating an ultrahigh output voltage (1.1 V at 98 % RH) through humidity-triggered galvanic reactions, enabling capacitor charging and light-emitting diode (LED) driving. Practical applicability is demonstrated through real-time respiratory monitoring, Morse code communication, and non-contact finger motion tracking, underscoring its utility in wearable electronics. This work provides a scalable and cost-effective approach to designing multifunctional humidity sensors with broad applicability in smart systems and healthcare.

Fabrication and characterization of laurel (laurus nobilis) essential oil nanoemulsion stabilized by sodium caseinate/modified α-cyclodextrin

Jiawen Liu,Song Li,Jie Shen,Jun Mei,Jing Xie

The direct application of essential oils in food systems faces challenges due to their volatility, strong odor, and instability. This study developed nanoemulsions encapsulating laurel ( Laurus nobilis ) essential oil (LEO) using sodium caseinate (SC) and octenyl succinic anhydride (OSA) modified α-cyclodextrin (α-CD) as composite stabilizers, aiming to enhance emulsion stability and bioactive efficacy. The results demonstrated that a 1:1 SC/OSA-α-CD ratio formed a dense reticular structure with minimal turbidity. NE-S1O1-8 M displayed uniform droplets, the smallest particle size (317.23 nm), and an 86° contact angle. Furthermore, under storage, centrifugation, or heating, NE-S1O1 showed superior stability with negligible changes in particle size or appearance. The encapsulation efficiency, antibacterial and antioxidant activities primarily depended on LEO concentration. The NE-S1O1-8 M emulsion exhibited optimal integrated bioactivity, demonstrating inhibition zones of 18.9 mm against S. putrefaciens and 17.1 mm against S. aureus , along with DPPH and ABTS radical scavenging rates of 79.2 % and 82.8 %, respectively. Although the encapsulation efficiency under this condition was slightly lower than that at 4 × MBC, it remained at a high level above 80 %. This study provides a novel approach for stabilizing active compound-loaded nanoemulsions suitable for food preservation applications.

Interfacial electronic modulation and coupling of NiFe LDH via α-Co(OH)2 for enhanced oxygen evolution

Mengke Li,Yang Yang,Yajie Zhang,XinZhuo Liu,Yulan Li,Xiaobin Niu

NiFe-layered double hydroxides (NiFe LDHs) are regarded as outstanding electrocatalysts for the oxygen evolution reaction (OER), but the inherent charge transport limitations hinder their practical application. Herein, we developed a 3D hierarchical α-Co(OH) 2 /NiFe LDH/NF composite catalyst via a simple electrodeposition-hydrothermal method. The introduction of α-Co(OH) 2 enables interfacial electron modulation with NiFe LDH, driving electron transfer from Ni/Co sites to Fe centers via multi-pathway coupling channels (Ni–O–Fe, Ni–O–Co, Co–O–Fe). This electron redistribution creates an optimized coordination environment that promotes the formation of high-valence Ni and Co species, subsequently facilitating the in situ formation of highly active phases (γ-NiFeOOH and CoOOH) during the OER process. The derived γ-NiFeOOH provides superior intrinsic activity, while the coexisting. CoOOH significantly enhances charge transport due to its high electronic conductivity. As a result, the composite achieves an overpotential of only 285 mV at a current density of 500 mA cm −2 , outperforming both NiFe LDH (372 mV) and α-Co(OH) 2 (441 mV). Additionally, this catalyst shows an excellent long-term stability at 100 mA cm −2 for 120 h. This work demonstrates that interfacial electronic modulation offers a strategy for designing efficient and durable OER catalysts capable of operating at industrial current densities.

Application of α-amylase-assisted extraction of longan seed polysaccharides in preparation of chromium-free tanning agents

Bo Jie Chen,Hock Eng Khoo,Xia Li,Biyu Peng

The present study examined the effect of α-amylase on complex carbohydrates in longan seeds and assessed the feasibility of using these carbohydrates as tanning agents. Enzymatic and hot-water extracts were purified and analyzed for their structural components and physicochemical properties. Enzymatic extraction with ultrasonic assistance yielded higher levels of bioactive components in longan seed polysaccharides (LSPs) than the non-enzymatic method. Dialdehyde longan seed polysaccharides (DLSPs) were prepared using LSPs and NaIO 4 . The effects of different NaIO 4 concentrations on molecular size, aldehyde content, other chemical compositions, structural characteristics, and tanning performance of DLSPs were evaluated. Increasing NaIO 4 concentrations decreased total sugars, polyphenols, and saponins, while raising protein content. The oxidant broke glycosidic bonds and oxidized o -dihydroxyl groups, forming reactive aldehyde groups. The DLSP-tanned leather exhibited a shrinkage temperature of 76.4 °C and tensile strength of 17.03 MPa. The tanning performance and bioactivity of DLSPs stem from lower molecular weight and high aldehyde and hydroxyl content. These polysaccharide samples exhibited good permeability and cross-linking reactivity within the collagen fiber network. Therefore, DLSPs are a promising new type of chromium-free tanning agents.

4, 9-dihydroxy-α-lapachone as a potent antiproliferation agent for triple-negative breast cancer via ferroptosis

Zhong He,Hui Long,Hongyue Ma,Wanrong Ran,Yinhong Song,Wenjuan Shang,Junhui Wang,Ye Qin,Zhangshuang Deng

Triple-negative breast cancer (TNBC) is the most aggressive and malignant breast cancer. Ferroptosis is an oxidative, iron-dependent form of regulated cell death. Ferroptosis-targeted therapies is a promising approach to improving treatment outcomes of TNBC. Combining death pathway inhibitors with relevant indices for ferroptosis and LipROS, this study uncovered that a natural product of 4, 9-dihydroxy- α -lapachone (DLN) from Catalpa bungei “jinsi” exhibited in vitro and in vivo inhibitory activity against TNBC via ferroptosis. The molecular mechanism is an activation of the FTH1 led to iron overload, and then inhibition of cysteine-glutamate antiporter (system Xc − ) and GPX4, which further sensitized TNBC cells to ferroptosis. This study clarified the pathway of DLN-induced cell death in TNBC treatment and exhibited its potential as therapeutic agent for TNBC.

Modified ethylene/α-octene co-polymer composites based on dual toughening of hydrogen bonding network and nanospheres

Zhiyi Huang,Tingting Liao,Xiaochun Liu,Jianyu Wu,Zilun Tang,Guoyi Pan,Huameng Liu,Xiaofeng Lin,Wenjing Lin,Yong Li,Yuxin Gu,Guobin Yi

Thermoplastic elastomer ethylene/α-octene co-polymer (POE) is a special polymer material with both elasticity and thermoplasticity. However, the nonpolarity and low-tensile strength of POE limit its application in polar materials and high-strength materials fields. In this study, we synthesized a specific molecule with C═C bonds and N  H bonds, which was introduced into POE to construct hydrogen bonding network, and the prepared modified POE is further blended with carboxyl terminated polystyrene nanospheres as toughening agent to prepare modified POE elastomer composites. Based on such dual toughening strategy containing chemical modification and physical toughening, the modified POE elastomer composites possess improved mechanical properties. The composites achieve a tensile strength of 21.4 MPa, elongation at break of 1268%, fracture energy of 109.6 MJ∙m −3 and exhibit improved thermal stability. Impressively, the tensile strength of reprocessed composites is restored to more than 90% of their original tensile strength even after four times of reprocessing steps, demonstrating excellent reusability.

Composite of Ge and α-MnSe in carbon nanofibers as a high- performance anode material for LIBs

Lirong He,Peng Zhou,Liping Wang,Mingyu Zhang,Qizhong Huang,Zhean Su,Xiaodong Wang,Ping Xu,Weijie Song,Renhao Zou

Improving the performance of anode materials is of great importance for lithium-ion batteries (LIBs). Transition metal selenides compositing carbon and germanium (Ge) have attracted extensive attention. In this work, an anode material that integrates Ge and α-MnSe in carbon nanofibers (CNFs) was first synthesized by heat treatment after electrospinning. The coupling of Ge with α-MnSe and carbon can cause the growth process of α-MnSe to occur inside the CNFs, which can buffer the volume change, refine the grains and avoid particles protruding from the surface of CNFs. In addition, the interconnected conductive network of Ge/α-MnSe@CNFs can provide fast diffusion channels for Li ions and improve the electrical conductivity . Importantly, there is a synergistic effect of Ge, α-MnSe, and CNFs on the anode material for LIBs. As expected, Ge/α-MnSe@CNFs exhibited an excellent performance with a capacity of 1514.7 mAh g −1 after 200 cycles at 0.1 A g −1 and 1030 mAh g −1 after 1000 cycles even at 1 A g −1 . Therefore, this new preparation strategy of Ge/α-MnSe@CNFs offers novel ideas to develop high-performance and long-life LIBs.

Cannabidiol alleviates carbon tetrachloride-induced liver fibrosis in mice by regulating NF-κB and PPAR-α pathways.

Run Ma,Na Xie,Yuanhui Shu,Yafeng Wu,Ping He,Yining Xiang,Yan Zhou,Yuping Wang

Liver fibrosis has become a serious public health problem that can develop into liver cirrhosis and hepatocellular carcinoma and even lead to death. Cannabidiol (CBD), which is an abundant nonpsychoactive component in the cannabis plant, exerts cytoprotective effects in many diseases and under pathological conditions. In our previous studies, CBD significantly attenuated liver injury induced by chronic and binge alcohol in a mouse model and oxidative bursts in human neutrophils. However, the effects of CBD on liver fibrosis and the underlying mechanisms still need to be further explored. A mouse liver fibrosis model was induced by carbon tetrachloride (CCl 4 ) for 10 weeks and used to explore the protective properties of CBD and related molecular mechanisms. After the injection protocol, serum samples and livers were used for molecular biology, biochemical and pathological analyses. The results showed that CBD could effectively improve liver function and reduce liver damage and liver fibrosis progression in mice; the expression levels of transaminase and fibrotic markers were reduced, and histopathological characteristics were improved. Moreover, CBD inhibited the levels of inflammatory cytokines and reduced the protein expression levels of p-NF-κB, NF-κB, p-IκBα, p-p38 MAPK, and COX-2 but increased the expression level of PPAR-α. We found that CBD-mediated protection involves inhibiting NF-κB and activating PPAR-α. In conclusion, these results suggest that the hepatoprotective effects of CBD may be due to suppressing the inflammatory response in CCl 4 -induced mice and that the NF-κB and PPAR-α signaling pathways might be involved in this process.

Multivalued Logic Assay of the Disease Marker of α-Ketoglutaric Acid by a Luminescent MOF-Based Biosensor

Xu Dai,Ji-Na Hao,Jinlou Gu,Yongsheng Li

α-Ketoglutaric acid (α-KA) is an important endogenous metabolite in the Krebs cycle and considered a critical marker for various diseases. Several approaches for identifying α-KA have been reported. However, most of them are limited to single-signal transduction modes in one assay and working in the suspension state, which easily cause quantification errors and lead to false-positive detection results. Herein, a multivalue-responsive and semi-solid EuMOF-gel (EuMOG) logic biosensor is first designed and fabricated, which can realize the specific, rapid, and easy-to-differentiate naked-eye detection of the disease-associated marker of α-KA in serum through implementing one-to-two logic operation with three multicolor gates. The implementation of one-to-two logic operation can be rationally achieved by assembling 2,6-naphthalenedicarboxylic acid as both the energy donor and blue-colored output 1, photoactive Eu3+ ions as the red-emissive output 2, and α-KA stimuli as an input and energy blocker between the dual spectrum-resolved outputs into one unit. With the specific input of α-KA among various analytes, the binary code of the logic decoder switches from (0,1) to (1,0) with an obvious color change from red to cyan. Moreover, by integrating the output chromaticity into the logical operations, the concentration levels of α-KA could be easily evaluated with the intelligent EuMOG detector, which has three multicolor gates in parallel encoding low (0,1), normal (1,1), and danger (1,0) statuses. Such multivalued logic biosensor provides a facile strategy to improve the analysis reliability of disease-associated biomarkers.

Expeditious and Cost-effective Synthesis of α-Amino Nitriles Using ZnCl2/hydrotalcite as a Recyclable Heterogeneous Catalyst

Xiaogang Yin,Qiong Yang,Hang Li,Qiudi Zhu,Xinyun Liu

Inhibition of α-glucosidase activity and non-enzymatic glycation by tannic acid: Inhibitory activity and molecular mechanism

Qian Huang,Wei-Ming Chai,Zuo-Yuan Ma,Chong Ou-Yang,Qi-Ming Wei,Shuang Song,Zheng-Rong Zou,Yi-Yuan Peng

The inhibition of α-glucosidase and glycation is considered as an effective approach for the treatment of type 2 diabetes. In this study, multispectroscopic and molecular docking techniques were employed to investigate the inhibition of tannic acid on α-glucosidase and glycation. Kinetics analyses revealed that tannic acid had a significant inhibition on α-glucosidase (IC 50  = 0.35 ± 0.02 μM) in a reversible and mixed competitive manner. The results acquired from fluorescence quenching and ANS-binding fluorescence methods revealed that tannic acid could bind to α-glucosidase and reduce the hydrophobic area on the surface of the enzyme . In addition, synchronous fluorescence analysis showed that tannic acid decreased the hydrophobicity of α-glucosidase and changed the conformation of the enzyme. In vitro glycation assays showed that tannic acid had strong inhibitory effects on the formation of fructosamine , dicarbonyl compounds, and fluorescent AGEs . ANS-binding fluorescence analysis showed that tannic acid could bind to BSA and reduce the hydrophobicity of BSA in glycation. Moreover, the results of molecular docking showed the interaction between tannic acid and α-glucosidase was mainly driven by hydrogen bond , electrostatic, and hydrophobic interaction. And the interaction between tannic acid and BSA was mainly driven by hydrogen bond and hydrophobic interaction.