bluuebunny/crossref_metadata_2025 huggingface dataset:
Towards High Surface Area α-Al2O3–Mn-Assisted Low Temperature Transformation
Authors: Jähnichen Tim , Carstens Simon , Franz Maximilian , Laufer Otto , Wenzel Marianne , Matysik Jörg , Enke Dirk
Published: April 2023

When impregnated with manganiferous precursors, γ-Al2O3 may be converted into α-Al2O3 under relatively mild and energy-saving conditions. In this work, a manganese assisted conversion to corundum at temperatures as low as 800 °C is investigated. To observe the alumina phase transition, XRD and solid-state 27Al-MAS-NMR are applied. By post-synthetical treatment in concentrated HCl, residual manganese is removed up to 3 wt.-%. Thereby, α-Al2O3 with a high specific surface area of 56 m2 g−1 is obtained after complete conversion. Just as for transition alumina, thermal stability is an important issue for corundum. Long-term stability tests were performed at 750 °C for 7 days. Although highly porous corundum was synthesized, the porosity decreased with time at common process temperatures.
Corrosion Behavior of Coated Low Carbon Steel in a Simulated PEMFC Environment
Authors: Avram Diana Nicoleta , Davidescu Corneliu Mircea , Hulka Iosif , Dan Mircea Laurentiu , Stanciu Elena Manuela , Pascu Alexandru , Mirza-Rosca Julia Claudia
Published: April 2023

Here, potential metallic bipolar plate (BP) materials were manufactured by laser coating NiCr-based alloys with different Ti additions on low carbon steel substrates. The titanium content within the coating varied between 1.5 and 12.5 wt%. Our present study focussed on electrochemically testing the laser cladded samples in a milder solution. The electrolyte used for all of the electrochemical tests consisted of a 0.1 M Na2SO4 solution (acidulated with H2SO4 at pH = 5) with the addition of 0.1 ppm F−. The corrosion resistance properties of the laser-cladded samples was evaluated using an electrochemical protocol, which consisted of the open circuit potential (OCP), electrochemical impedance spectroscopy (EIS) measurements, and potentiodynamic polarization, followed by potentiostatic polarization under simulated proton exchange membrane fuel cell (PEMFC) anodic and cathodic environments for 6 h each. After the samples were subjected to potentiostatic polarization, the EIS measurements and potentiodynamic polarization were repeated. The microstructure and chemical composition of the laser cladded samples were investigated by scanning electron microscopy (SEM) combined with energy-dispersive X-ray spectroscopy (EDX) analysis.
Biocomposite Foams with Multimodal Cellular Structures Based on Cork Granulates and Microwave Processed Egg White Proteins
Authors: Luciano Giorgio , Vignali Adriano , Vignolo Maurizio , Utzeri Roberto , Bertini Fabio , Iannace Salvatore
Published: April 2023

In an effort to reduce greenhouse gas emission, reduce the consumption of natural resources, and increase the sustainability of biocomposite foams, the present study focuses on the recycling of cork processing waste for the production of lightweight, non-structural, fireproof thermal and acoustic insulating panels. Egg white proteins (EWP) were used as a matrix model to introduce an open cell structure via a simple and energy-efficient microwave foaming process. Samples with different compositions (ratio of EWP and cork) and additives (eggshells and inorganic intumescent fillers) were prepared with the aim of correlating composition, cellular structures, flame resistance, and mechanical properties.
Study on Corrosion Behavior and Mechanism of Ultrahigh-Strength Hot-Stamping Steel Based on Traditional and Compact Strip-Production Processes
Authors: Ma Guoqiang , Chen Yimian , Wang Shuize , Wu Honghui , Gao Junheng , Wu Guilin , Mao Xinping
Published: April 2023

Hot-stamping steel is a type of high-strength steel that is mainly used in key safety components such as the front and rear bumpers, A-pillars, and B-pillars of vehicles. There are two methods of producing hot-stamping steel, i.e., the traditional process and the near net shape of compact strip production (CSP) process. To assess the potential risks of producing hot-stamping steel using CSP, the microstructure and mechanical properties, and especially the corrosion behavior were focused on between the traditional and CSP processes. The original microstructure of hot-stamping steel produced by the traditional process and the CSP process is different. After quenching, the microstructures transform into full martensite, and their mechanical properties meet the 1500 MPa grade. Corrosion tests showed that the faster the quenching speeds, the smaller the corrosion rate of the steel. The corrosion current density changes from 15 to 8.6 μA·cm−2. The corrosion resistance of hot-stamping steel produced by the CSP process is slightly better than that of traditional processes, mainly since the inclusion size and distribution density of CSP-produced steel were both smaller than those of the traditional process. The reduction of inclusions reduces the number of corrosion sites and improves the corrosion resistance of steel.
Three-Dimensional PLGA Nanofiber-Based Microchip for High-Efficiency Cancer Cell Capture
Authors: Qi Mengting , Ruan Meilin , Liang Jinjin , Zhang Zhengtao , Chen Chaohui , Cao Yiping , He Rongxiang
Published: April 2023

A 3D network capture substrate based on poly(lactic-co-glycolic acid) (PLGA) nanofibers was studied and successfully used for high-efficiency cancer cell capture. The arc-shaped glass micropillars were prepared by chemical wet etching and soft lithography. PLGA nanofibers were coupled with micropillars by electrospinning. Given the size effect of the microcolumn and PLGA nanofibers, a three-dimensional of micro-nanometer spatial network was prepared to form a network cell trapping substrate. After the modification of a specific anti-EpCAM antibody, MCF-7 cancer cells were captured successfully with a capture efficiency of 91%. Compared with the substrate composed of 2D nanofibers or nanoparticles, the developed 3D structure based on microcolumns and nanofibers had a greater contact probability between cells and the capture substrate, leading to a high capture efficiency. Cell capture based on this method can provide technical support for rare cells in peripheral blood detection, such as circulating tumor cells and circulating fetal nucleated red cells.
Enhancement of Supercapacitor Performance of Electrochemically Grown Nickel Oxide by Graphene Oxide
Authors: BinSabt Mohammad H. , Galal Ahmed , Abdel Nazeer Ahmed
Published: April 2023

β-Ni(OH)2 and β-Ni(OH)2/graphene oxide (GO) were prepared on an Ni foil electrode using the electrochemical cyclic voltammetry formed in 0.5 M KOH solution. Several surface analyses such as XPS, XRD, and Raman spectroscopies were used to confirm the chemical structure of the prepared materials. The morphologies were determined using SEM and AFM. The addition of the graphene oxide layer showed a remarkable increase in the specific capacitance of the hybrid. Through the measurements, the specific capacitance values were 280 F g−1 and 110 F g−1 after and before adding 4 layers of GO, respectively. The supercapacitor displays high stability until 500 cycles are charged and discharged almost without a loss in its capacitance values.
A Point Cloud-Based Deep Learning Model for Protein Docking Decoys Evaluation
Authors: Han Ye , Zhang Simin , He Fei
Published: April 2023

Protein-protein docking reveals the process and product in protein interactions. Typically, a protein docking works with a docking model sampling, and then an evaluation method is used to rank the near-native models out from a large pool of generated decoys. In practice, the evaluation stage is the bottleneck to perform accurate protein docking. In this paper, PointNet, a deep learning algorithm based on point cloud, is applied to evaluate protein docking models. The proposed architecture is able to directly learn deep representations carrying the geometrical properties and atomic attributes from the 3D structural data of protein decoys. The experimental results show that the informative representations can benefit our proposed method to outperform other algorithms.
On Translation Curves and Geodesics in Sol14
Authors: Erjavec Zlatko , Maretić Marcel
Published: April 2023

A translation curve in a homogeneous space is a curve such that for a given unit vector at the origin, translation of this vector is tangent to the curve in its every point. Translation curves coincide with geodesics in most Thurston spaces, but not in twisted product Thurston spaces. Moreover, translation curves often seem more intuitive and simpler than geodesics. In this paper, we determine translation curves in Sol14 space. Their curvature properties are discussed and translation spheres are presented. Finally, characterization of geodesics in Sol14 space is given.
Two Generalizations of the Core Inverse in Rings with Some Applications
Authors: Xu San-Zhang , Benítez Julio , Wang Ya-Qian , Mosić Dijana
Published: April 2023

In this paper, we introduce two new generalized core inverses, namely, the (p,q,m)-core inverse and the ⟨p,q,n⟩-core inverse; both extend the inverses of the ⟨i,m⟩-core inverse, the (j,m)-core inverse, the core inverse, the core-EP inverse and the DMP-inverse.
Efficacy of Platelet-Rich Plasma Therapy in Oral Lichen Planus: A Systematic Review
Authors: Sriram Shyamkumar , Hasan Shamimul , Alqarni Abdullah , Alam Tanveer , Kaleem Sultan Mohammed , Aziz Shahid , Durrani Humayoun Khan , Ajmal Muhammed , Dawasaz Ali Azhar , Saeed Shazina
Published: April 2023

Background and Objectives: Oral lichen planus (OLP) is an autoimmune, mucocutaneous, oral potentially malignant disorder (OPMD), which characteristically manifests with chronic, recalcitrant lesions, with frequent flare-ups and remissions. The precise etiopathogenesis of OLP is still debatable, although it is believed to be a T-cell-mediated disorder of an unidentified antigen. Despite the availability of various treatments, no cure for OLP exists due to its recalcitrant nature and idiopathic etiology. Platelet-rich plasma (PRP) has antioxidant, anti-inflammatory, and immunomodulatory properties, in addition to its regulatory action on keratinocyte differentiation and proliferation. These salient properties substantiate the possible role of PRP in the treatment of OLP. Our systematic review focuses on assessing the therapeutic potential of PRP as a treatment modality in OLP. Materials and Methods: We conducted a detailed literature search for studies assessing PRP as a therapeutic regimen in OLP, using the Google Scholar and PubMed/MEDLINE search engines. The search was limited to studies published from January 2000 to January 2023 and included a combination of Medical Subject Heading (MeSH) terms. ROBVIS analysis was carried out for the assessment of publication bias. Descriptive statistics were performed using Microsoft Excel. Results: This systematic review included five articles that met the inclusion criteria. Most of the included studies demonstrated that PRP treatment considerably ameliorated both objective and subjective symptoms in OLP subjects, with comparable efficacy to the standard corticosteroid treatment. Further, PRP therapy offers the added benefit of minimal adverse effects and recurrences. Conclusion: This systematic review suggests that PRP has significant therapeutic potential for treating OLP. However, further research with larger sample sizes is imperative to corroborate these findings.
Long-Term Chromatic Durability of White Spot Lesions through Employment of Infiltration Resin Treatment
Authors: Puleio Francesco , Di Spirito Federica , Lo Giudice Giuseppe , Pantaleo Giuseppe , Rizzo David , Lo Giudice Roberto
Published: April 2023

Background and Objectives: White spot lesions (WSLs) denote regions of subsurface demineralization on the enamel that manifest as opaque and milky-white regions. Treatment for WSLs is essential for both clinical and aesthetic reasons. Resin infiltration has been identified as the most efficacious solution for alleviating WSLs, but studies with long-term monitoring are scarce. The aim of this clinical study is to assess the color change stability of the lesion after four years of implementing the resin infiltration technique. Materials and Methods: Forty non-cavity and unrestored white spot lesions (WSLs) were treated with the resin infiltration technique. The color of the WSLs and adjacent healthy enamel (SAE) was assessed using a spectrophotometer at T0 (baseline), T1 (after treatment), T2 (1 year after) and T3 (4 years after). The Wilcoxon test was utilized to determine the significance of the variation of color (ΔE) between WSLs and SAE over the observed time periods. Results: When comparing the color difference ΔE (WSLs-SAE) at T0-T1, the Wilcoxon test demonstarated a statistically significant difference (p < 0.05). For ΔE (WSLs-SAE) at T1-T2 and T1-T3, the color variation was not statistically significant (p = 0.305 and p = 0.337). Conclusions: The study’s findings indicate that the resin infiltration technique is an effective solution for resolving the appearance of WSLs, and the results have demonstrated stability for a minimum of four years.
Metabolomic Study of Aging in fa/fa Rats: Multiplatform Urine and Serum Analysis
Authors: Pelantová Helena , Tomášová Petra , Šedivá Blanka , Neprašová Barbora , Mráziková Lucia , Kuneš Jaroslav , Železná Blanka , Maletínská Lenka , Kuzma Marek
Published: April 2023

Zucker fatty (fa/fa) rats represent a well-established and widely used model of genetic obesity. Because previous metabolomic studies have only been published for young fa/fa rats up to 20 weeks of age, which can be considered early maturity in male fa/fa rats, the aim of our work was to extend the metabolomic characterization to significantly older animals. Therefore, the urinary profiles of obese fa/fa rats and their lean controls were monitored using untargeted NMR metabolomics between 12 and 40 weeks of age. At the end of the experiment, the rats were also characterized by NMR and LC-MS serum analysis, which was supplemented by a targeted LC-MS analysis of serum bile acids and neurotransmitters. The urine analysis showed that most of the characteristic differences detected in young obese fa/fa rats persisted throughout the experiment, primarily through a decrease in microbial co-metabolite levels, the upregulation of the citrate cycle, and changes in nicotinamide metabolism compared with the age-related controls. The serum of 40-week-old obese rats showed a reduction in several bile acid conjugates and an increase in serotonin. Our study demonstrated that the fa/fa model of genetic obesity is stable up to 40 weeks of age and is therefore suitable for long-term experiments.
Acetate Production from Syngas Produced from Lignocellulosic Biomass Materials along with Gaseous Fermentation of the Syngas: A Review
Authors: Harahap Budi Mandra , Ahring Birgitte K.
Published: April 2023

Biotransformation of lignocellulose-derived synthetic gas (syngas) into acetic acid is a promising way of creating biochemicals from lignocellulosic waste materials. Acetic acid has a growing market with applications within food, plastics and for upgrading into a wide range of biofuels and bio-products. In this paper, we will review the microbial conversion of syngas to acetic acid. This will include the presentation of acetate-producing bacterial strains and their optimal fermentation conditions, such as pH, temperature, media composition, and syngas composition, to enhance acetate production. The influence of syngas impurities generated from lignocellulose gasification will further be covered along with the means to alleviate impurity problems through gas purification. The problem with mass transfer limitation of gaseous fermentation will further be discussed as well as ways to improve gas uptake during the fermentation.
In Silico Analysis of a GH3 β-Glucosidase from Microcystis aeruginosa CACIAM 03
Authors: Serra Gustavo Marques , Siqueira Andrei Santos , de Molfetta Fábio Alberto , Santos Agenor Valadares , Xavier Luciana Pereira
Published: April 2023

Cyanobacteria are rich sources of secondary metabolites and have the potential to be excellent industrial enzyme producers. β-glucosidases are extensively employed in processing biomass degradation as they mediate the most crucial step of bioconversion of cellobiose (CBI), hence controlling the efficiency and global rate of biomass hydrolysis. However, the production and availability of these enzymes derived from cyanobacteria remains limited. In this study, we evaluated the β-glucosidase from Microcystis aeruginosa CACIAM 03 (MaBgl3) and its potential for bioconversion of cellulosic biomass by analyzing primary/secondary structures, predicting physicochemical properties, homology modeling, molecular docking, and simulations of molecular dynamics (MD). The results showed that MaBgl3 derives from an N-terminal domain folded as a distorted β-barrel, which contains the conserved His–Asp catalytic dyad often found in glycosylases of the GH3 family. The molecular docking results showed relevant interactions with Asp81, Ala271 and Arg444 residues that contribute to the binding process during MD simulation. Moreover, the MD simulation of the MaBgl3 was stable, shown by analyzing the root mean square deviation (RMSD) values and observing favorable binding free energy in both complexes. In addition, experimental data suggest that MaBgl3 could be a potential enzyme for cellobiose-hydrolyzing degradation.
Is There a Future for Traditional Immunogens When We Have mRNA?
Authors: Kyuregyan Karen K. , Jansons Juris , Isaguliants Maria
Published: April 2023

As the SARS-CoV-2 pandemic ends and we enter into a post-pandemic world, it is the time to reflect on the lessons learned [...]
Indium Recovery from Jarosite Pb–Ag Tailings Waste (Part 1)
Authors: Janošević Miloš , Conić Vesna , Božić Dragana , Avramović Ljiljana , Jovanović Ivana , Kamberović Željko , Marjanović Saša
Published: April 2023

The processing of zinc ore using hydrometallurgical methods leads to the formation and accumulation of a by-product called jarosite, which contains concentrated precious metals. In this study, we propose the recovery of In and its separation from Cu, Zn, Fe, Pb, and Ag. This study also presents a proposal for a new technological procedure for jarosite treatment. First we roasted the jarosite, and then the calcine collected was leached in water. The leaching extraction values obtained for Cu, Zn, Fe, and In were 91.07%, 91.97%, 9.60%, and 100.0%, respectively. Following the leaching of the roasted material in water, Pb, Ag, and most of the Fe obtained remained in the solid residue. The leaching solution was treated further by a precipitation process using NaOH, where In and Fe were precipitated and consequently separated from Cu and Zn. The In (OH)3 and Fe(OH)3 precipitates were dissolved further in a diluted H2SO4 solution, and then the cementation of In with Al was performed. We used HCl acid to remove Al from the In, after which unwrought In was obtained.
Potential of Atlantic Codfish (Gadus morhua) Skin Collagen for Skincare Biomaterials
Authors: Rodrigues Cristina V. , Sousa Rita O. , Carvalho Ana C. , Alves Ana L. , Marques Catarina F. , Cerqueira Mariana T. , Reis Rui L. , Silva Tiago H.
Published: April 2023

Collagen is the major structural protein in extracellular matrix present in connective tissues, including skin, being considered a promising material for skin regeneration. Marine organisms have been attracting interest amongst the industry as an alternative collagen source. In the present work, Atlantic codfish skin collagen was analyzed, to evaluate its potential for skincare. The collagen was extracted from two different skin batches (food industry by-product) using acetic acid (ASColl), confirming the method reproducibility since no significant yield differences were observed. The extracts characterization confirmed a profile compatible with type I collagen, without significant differences between batches or with bovine skin collagen (a reference material in biomedicine). Thermal analyses suggested ASColl’s native structure loss at 25 °C, and an inferior thermal stability to bovine skin collagen. No cytotoxicity was found for ASColl up to 10 mg/mL in keratinocytes (HaCaT cells). ASColl was used to develop membranes, which revealed smooth surfaces without significative morphological or biodegradability differences between batches. Their water absorption capacity and water contact angle indicated a hydrophilic feature. The metabolic activity and proliferation of HaCaT were improved by the membranes. Hence, ASColl membranes exhibited attractive characteristics to be applied in the biomedical and cosmeceutical field envisaging skincare.
Naproxen-Derived New Compound Inhibits the NF-κB, MAPK and PI3K/Akt Signaling Pathways Synergistically with Resveratrol in RAW264.7 Cells
Authors: Ou Yi , You Zonglin , Yao Min , Cao Yingfan , Xue Xiu , Chen Min , Wu Rihui , Gan Lishe , Li Dongli , Wu Panpan , Xu Xuetao , Wong Wingleung , Wong Vincent Kam Wai , Liu Wenfeng , Ye Jiming , Jin Jingwei
Published: April 2023

Naproxen is widely used for anti-inflammatory treatment but it can lead to serious side effects. To improve the anti-inflammatory activity and safety, a novel naproxen derivative containing cinnamic acid (NDC) was synthesized and used in combination with resveratrol. The results showed that the combination of NDC and resveratrol at different ratios have a synergistic anti-inflammatory efficacy in RAW264.7 macrophage cells. It was indicated that the combination of NDC and resveratrol at a ratio of 2:1 significantly inhibited the expression of carbon monoxide (NO), tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), induced nitric oxide synthase (iNOS), cyclooxygenase 2 (COX-2) and reactive oxygen species (ROS) without detectable side effects on cell viability. Further studies revealed that these anti-inflammatory effects were mediated by the activation of nuclear factor kappa-B (NF-κB), mitogen-activated protein kinase (MAPK) and phosphoinositide-3 kinase (PI3K)/protein kinase B (Akt) signaling pathways, respectively. Taken together, these results highlighted the synergistic NDC and resveratrol anti-inflammatory activity that could be further explored as a strategy for the treatment of inflammatory disease with an improved safety profile.
A Self-Cleaning TiO2 Bacterial Cellulose Super-Hydrophilic Underwater Super-Oleophobic Composite Membrane for Efficient Oil–Water Separation
Authors: Cui Yawen , Zheng Xudong , Xu Tongtong , Ji Biao , Mei Jinfeng , Li Zhongyu
Published: April 2023

Due to the increasingly serious problem of offshore oil spills, research related to oil–water separation has attracted more and more attention. Here, we prepared a super-hydrophilic/underwater super-oleophobic membrane (hereinafter referred to as BTA) using poly-dopamine (PDA) to adhesive TiO2 nanoparticles on the surface of bacterial cellulose, coated with sodium alienate by vacuum-assisted filtration technique. This demonstrates its excellent underwater super-oleophobic property. Its contact angle is about 153°. Remarkably, BTA has 99% separation efficiency. More importantly, BTA still showed excellent anti-pollution property under ultraviolet light after 20 cycles. BTA has the advantages of low cost, environmentally friendliness and good anti-fouling performance. We believe it can play an important role in dealing with problems related to oily wastewater.
Design and Application of Thymol Electrochemical Sensor Based on the PtNPs-CPOFs-MWCNTs Composite
Authors: Li Na , Zhang Hongyue , Cui Min , Ren Jujie , Huang Jingru , Sun Bao , Zhao Haiyan , Zhang Cong
Published: April 2023

In this study, the preparation of covalent polyoxometalate organic frameworks (CPOFs) is introduced using the idea of polyoxometalate and covalent organic frameworks. Firstly, the prepared polyoxometalate was functionalized with an amine group (NH2-POM-NH2), and then the CPOFs were prepared by a solvothermal Schiff base reaction with NH2-POM-NH2 and 2,4,6-trihydroxybenzene-1,3,5-tricarbaldehyde (Tp) as monomers. After the incorporation of PtNPs and MWCNTs into the CPOFs material, the PtNPs-CPOFs-MWCNTs nanocomposites, which possess excellent catalytic activity and electrical conductivity, were formed and utilized as new electrode materials for the electrochemical thymol sensors. The obtained PtNPs-CPOFs-MWCNTs composite exhibits excellent activity toward thymol, which is attributable to its large special surface area, good conductivity and the synergistic catalysis of each component. Under optimal experimental conditions, the sensor presented a good electrochemical response to thymol. The sensor shows two good linear relationships between the current and thymol concentration in the range of 2–65 μM (R2 = 0.996) and 65–810 μM (R2 = 0.997), with the corresponding sensitivity of 72.7 μA mM−1 and 30.5 μA mM−1, respectively. Additionally, the limit of detection (LOD) was calculated to be 0.2 μM (S/N = 3). At the same time, the prepared thymol electrochemical sensor revealed superior stability and selectivity. The constructed PtNPs-CPOFs-MWCNT electrochemical sensor is the first example of thymol detection.
A QSAR Study for Antileishmanial 2-Phenyl-2,3-dihydrobenzofurans †
Authors: Bernal Freddy A. , Schmidt Thomas J.
Published: April 2023

Leishmaniasis, a parasitic disease that represents a threat to the life of millions of people around the globe, is currently lacking effective treatments. We have previously reported on the antileishmanial activity of a series of synthetic 2-phenyl-2,3-dihydrobenzofurans and some qualitative structure–activity relationships within this set of neolignan analogues. Therefore, in the present study, various quantitative structure–activity relationship (QSAR) models were created to explain and predict the antileishmanial activity of these compounds. Comparing the performance of QSAR models based on molecular descriptors and multiple linear regression, random forest, and support vector regression with models based on 3D molecular structures and their interaction fields (MIFs) with partial least squares regression, it turned out that the latter (i.e., 3D-QSAR models) were clearly superior to the former. MIF analysis for the best-performing and statistically most robust 3D-QSAR model revealed the most important structural features required for antileishmanial activity. Thus, this model can guide decision-making during further development by predicting the activity of potentially new leishmanicidal dihydrobenzofurans before synthesis.
Phytochemicals, Bioactive Properties and Commercial Potential of Calamondin (Citrofortunella microcarpa) Fruits: A Review
Authors: Venkatachalam Karthikeyan , Charoenphun Narin , Srean Pao , Yuvanatemiya Vasin , Pipatpanukul Chinnawut , Pakeechai Kanokporn , Parametthanuwat Thanya , Wongsa Jittimon
Published: April 2023

The calamondin (Citrofortunella microcarpa) is a hybrid citrus fruit resulting from the crossing of a mandarin orange with a kumquat. It is a small, round-shaped fruit with thin, smooth skin ranging from orange to dark red. The aroma of the fruit is distinctive and unique. Calamondin is an excellent source of Vitamin C, D-Limonene, and essential oils, providing benefits to the immune system, as well as anti-inflammatory, anti-cancer, anti-diabetic, anti-angiogenic, and anti-cancer properties, and it exhibits various therapeutic effects. It also contains a good amount of dietary fiber from pectin. Its distinctive flavor and high juice content make calamondin juice a popular ingredient in many international cuisines. The juice also contains bioactive compounds, such as phenolics and flavonoids, which are a potential source of antioxidant properties. All parts of the calamondin fruit, including the juice, pulp, seeds, and peel, can be used in various applications, from food products like juices, powders, and candies to non-food uses in herbal medicine and cosmetics, showcasing their versatility and unique properties. This review will examine various bioactive components of calamondin and their related medicinal effects, and provide guidelines for their utilization, processing, and value addition on a commercial scale.
Biofabrication of Fe3O4 Nanoparticles from Spirogyra hyalina and Ajuga bracteosa and Their Antibacterial Applications
Authors: Sharif Muhammad Shakeeb , Hameed Hajra , Waheed Abdul , Tariq Muhammad , Afreen Afshan , Kamal Asif , Mahmoud Eman A. , Elansary Hosam O. , Saqib Saddam , Zaman Wajid
Published: April 2023

Iron oxide nanoparticles (NPs) have attracted substantial interest due to their superparamagnetic features, biocompatibility, and nontoxicity. The latest progress in the biological production of Fe3O4 NPs by green methods has improved their quality and biological applications significantly. In this study, the fabrication of iron oxide NPs from Spirogyra hyalina and Ajuga bracteosa was conducted via an easy, environmentally friendly, and cost-effective process. The fabricated Fe3O4 NPs were characterized using various analytical methods to study their unique properties. UV-Vis absorption peaks were observed in algal and plant-based Fe3O4 NPs at 289 nm and 306 nm, respectively. Fourier transform infrared (FTIR) spectroscopy analyzed diverse bioactive phytochemicals present in algal and plant extracts that functioned as stabilizing and capping agents in the fabrication of algal and plant-based Fe3O4 NPs. X-ray diffraction of NPs revealed the crystalline nature of both biofabricated Fe3O4 NPs and their small size. Scanning electron microscopy (SEM) revealed that algae and plant-based Fe3O4 NPs are spherical and rod-shaped, averaging 52 nm and 75 nm in size. Energy dispersive X-ray spectroscopy showed that the green-synthesized Fe3O4 NPs require a high mass percentage of iron and oxygen to ensure their synthesis. The fabricated plant-based Fe3O4 NPs exhibited stronger antioxidant properties than algal-based Fe3O4 NPs. The algal-based NPs showed efficient antibacterial potential against E. coli, while the plant-based Fe3O4 NPs displayed a higher zone of inhibition against S. aureus. Moreover, plant-based Fe3O4 NPs exhibited superior scavenging and antibacterial potential compared to the algal-based Fe3O4 NPs. This might be due to the greater number of phytochemicals in plants that surround the NPs during their green fabrication. Hence, the capping of bioactive agents over iron oxide NPs improves antibacterial applications.
Inclusion Complexes of 3,4-Ethylenedioxythiophene with Per-Modified β- and γ-Cyclodextrins
Authors: Farcas Aurica , Resmerita Ana-Maria , Balan-Porcarasu Mihaela , Cojocaru Corneliu , Peptu Cristian , Sava Ion
Published: April 2023

Herein, we report the synthesis of inclusion complexes (ICs) based on 3,4-ethylenedioxythiophene (EDOT) with permethylated β-cyclodextrins (TMe-βCD) and permethylated γ-cyclodextrins (TMe-γCD) host molecules. To prove the synthesis of such ICs, molecular docking simulation, UV-vis titrations in water, 1H-NMR, and H-H ROESY, as well as matrix-assisted laser desorption ionization mass spectroscopy (MALDI TOF MS) and thermogravimetric analysis (TGA) were carried out on each of the EDOT∙TMe-βCD and EDOT∙TMe-γCD samples. The results of computational investigations reveal the occurrence of hydrophobic interactions, which contribute to the insertion of the EDOT guest inside the macrocyclic cavities and a better binding of the neutral EDOT to TMe-βCD. The H-H ROESY spectra show correlation peaks between H-3 and H-5 of hosts and the protons of the guest EDOT, suggesting that the EDOT molecule is included inside the cavities. The MALDI TOF MS analysis of the EDOT∙TMe-βCD solutions clearly reveals the presence of MS peaks corresponding to sodium adducts of the species associated with the complex formation. The IC preparation shows remarkable improvements in the physical properties of EDOT, rendering it a plausible alternative to increasing its aqueous solubility and thermal stability.
Synthesis and Characterization of Carvedilol-Etched Halloysite Nanotubes Composites with Enhanced Drug Solubility and Dissolution Rate
Authors: Maggi Lauretta , Urru Claudia , Friuli Valeria , Ferrara Chiara , Conti Debora Maria , Bruni Giovanna , Capsoni Doretta
Published: April 2023

Carvedilol is a poorly water-soluble drug employed to treat chronic heart failure. In this study, we synthesize new carvedilol-etched halloysite nanotubes (HNTs) composites to enhance solubility and dissolution rate. The simple and feasible impregnation method is used for carvedilol loading (30–37% weight). Both the etched HNTs (acidic HCl and H2SO4 and alkaline NaOH treatments) and the carvedilol-loaded samples are characterized by various techniques (XRPD, FT-IR, solid-state NMR, SEM, TEM, DSC, and specific surface area). The etching and loading processes do not induce structural changes. The drug and carrier particles are in intimate contact and their morphology is preserved, as demonstrated by TEM images. The 27Al and 13C solid-state NMR and FT-IR findings show that carvedilol interactions involve the external siloxane surface, especially the aliphatic carbons, the functional groups, and, by inductive effect, the adjacent aromatic carbons. All the carvedilol–halloysite composites display enhanced dissolution rate, wettability, and solubility, as compared to carvedilol. The best performances are obtained for the carvedilol–halloysite system based on HNTs etched with HCl 8M, which exhibits the highest value of specific surface area (91 m2 g−1). The composites make the drug dissolution independent of the environmental conditions of the gastrointestinal tract and its absorption less variable, more predictable, and independent from the pH of the medium.
Antiseizure Properties of Histamine H3 Receptor Antagonists Belonging 3,4-Dihydroquinolin-2(1H)-Ones
Authors: Hua Yi , Song Mingxia , Guo Qiaoyue , Luo Yiqin , Deng Xianqing , Huang Yushan
Published: April 2023

H3R is becoming an attractive and promising target for epilepsy treatment as well as the discovery of antiepileptics. In this work, a series of 6-aminoalkoxy-3,4-dihydroquinolin-2(1H)-ones was prepared to screen their H3R antagonistic activities and antiseizure effects. The majority of the target compounds displayed a potent H3R antagonistic activity. Among them, compounds 2a, 2c, 2h, and 4a showed submicromolar H3R antagonistic activity with an IC50 of 0.52, 0.47, 0.12, and 0.37 μM, respectively. The maximal electroshock seizure (MES) model screened out three compounds (2h, 4a, and 4b) with antiseizure activity. Meanwhile, the pentylenetetrazole (PTZ)-induced seizure test gave a result that no compound can resist the seizures induced by PTZ. Additionally, the anti-MES action of compound 4a fully vanished when it was administrated combined with an H3R agonist (RAMH). These results showed that the antiseizure role of compound 4a might be achieved by antagonizing the H3R receptor. The molecular docking of 2h, 4a, and PIT with the H3R protein predicted their possible binding patterns and gave a presentation that 2h, 4a, and PIT had a similar binding model with H3R.
Activated Carbon with Ultrahigh Specific Surface Derived from Bamboo Shoot Shell through K2FeO4 Oxidative Pyrolysis for Adsorption of Methylene Blue
Authors: He Yuyu , Ni Liangmeng , Gao Qi , Ren Hao , Su Mengfu , Hou Yanmei , Liu Zhijia
Published: April 2023

To effectively remove methylene blue (MB) from dye wastewater, a novel activated carbon (BAC) was manufactured through co-pyrolysis of bamboo shoot shell and K2FeO4. The activation process was optimized to a temperature of 750 °C and an activation time of 90 min based on its excellent adsorption capacity of 560.94 mg/g with a yield of 10.03%. The physicochemical and adsorption properties of BACs were investigated. The BAC had an ultrahigh specific surface area of 2327.7 cm2/g and abundant active functional groups. The adsorption mechanisms included chemisorption and physisorption. The Freundlich model could be used to describe the isothermal adsorption of MB. The kinetics confirmed that the adsorption of MB belonged to the pseudo-second-order model. Intra-particle diffusion was the main rate-limiting step. The thermodynamic study showed that the adsorption process was endothermic and temperature was beneficial for the improvement of adsorption property. Furthermore, the removal rate of MB was 63.5% after three cycles. The BAC will have great potential for commercial development for purifying dye wastewater.
An Expedited Route to Optical and Electronic Properties at Finite Temperature via Unsupervised Learning
Authors: Perrella Fulvio , Coppola Federico , Rega Nadia , Petrone Alessio
Published: April 2023

Electronic properties and absorption spectra are the grounds to investigate molecular electronic states and their interactions with the environment. Modeling and computations are required for the molecular understanding and design strategies of photo-active materials and sensors. However, the interpretation of such properties demands expensive computations and dealing with the interplay of electronic excited states with the conformational freedom of the chromophores in complex matrices (i.e., solvents, biomolecules, crystals) at finite temperature. Computational protocols combining time dependent density functional theory and ab initio molecular dynamics (MD) have become very powerful in this field, although they require still a large number of computations for a detailed reproduction of electronic properties, such as band shapes. Besides the ongoing research in more traditional computational chemistry fields, data analysis and machine learning methods have been increasingly employed as complementary approaches for efficient data exploration, prediction and model development, starting from the data resulting from MD simulations and electronic structure calculations. In this work, dataset reduction capabilities by unsupervised clustering techniques applied to MD trajectories are proposed and tested for the ab initio modeling of electronic absorption spectra of two challenging case studies: a non-covalent charge-transfer dimer and a ruthenium complex in solution at room temperature. The K-medoids clustering technique is applied and is proven to be able to reduce by ∼100 times the total cost of excited state calculations on an MD sampling with no loss in the accuracy and it also provides an easier understanding of the representative structures (medoids) to be analyzed on the molecular scale.
The Microwave Rotational Electric Resonance (RER) Spectrum of Benzothiazole
Authors: Hadki Hamza El , Koziol Kenneth J. , Kabbaj Oum Keltoum , Komiha Najia , Kleiner Isabelle , Nguyen Ha Vinh Lam
Published: April 2023

The microwave spectra of benzothiazole were measured in the frequency range 2–26.5 GHz using a pulsed molecular jet Fourier transform microwave spectrometer. Hyperfine splittings arising from the quadrupole coupling of the 14N nucleus were fully resolved and analyzed simultaneously with the rotational frequencies. In total, 194 and 92 hyperfine components of the main species and the 34S isotopologue, respectively, were measured and fitted to measurement accuracy using a semi-rigid rotor model supplemented by a Hamiltonian accounting for the 14N nuclear quadrupole coupling effect. Highly accurate rotational constants, centrifugal distortion constants, and 14N nuclear quadrupole coupling constants were deduced. A large number of method and basis set combinations were used to optimize the molecular geometry of benzothiazole, and the calculated rotational constants were compared with the experimentally determined constants in the course of a benchmarking effort. The similar value of the χcc quadrupole coupling constant when compared to other thiazole derivatives indicates only very small changes of the electronic environment at the nitrogen nucleus in these compounds. The small negative inertial defect of −0.056 uÅ2 hints that low-frequency out-of-plane vibrations are present in benzothiazole, similar to the observation for some other planar aromatic molecules.
Virtual Screening Strategy to Identify Retinoic Acid-Related Orphan Receptor γt Modulators
Authors: Jokinen Elmeri M. , Niemeläinen Miika , Kurkinen Sami T. , Lehtonen Jukka V. , Lätti Sakari , Postila Pekka A. , Pentikäinen Olli T. , Niinivehmas Sanna P.
Published: April 2023

Molecular docking is a key method used in virtual screening (VS) campaigns to identify small-molecule ligands for drug discovery targets. While docking provides a tangible way to understand and predict the protein-ligand complex formation, the docking algorithms are often unable to separate active ligands from inactive molecules in practical VS usage. Here, a novel docking and shape-focused pharmacophore VS protocol is demonstrated for facilitating effective hit discovery using retinoic acid receptor-related orphan receptor gamma t (RORγt) as a case study. RORγt is a prospective target for treating inflammatory diseases such as psoriasis and multiple sclerosis. First, a commercial molecular database was flexibly docked. Second, the alternative docking poses were rescored against the shape/electrostatic potential of negative image-based (NIB) models that mirror the target’s binding cavity. The compositions of the NIB models were optimized via iterative trimming and benchmarking using a greedy search-driven algorithm or brute force NIB optimization. Third, a pharmacophore point-based filtering was performed to focus the hit identification on the known RORγt activity hotspots. Fourth, free energy binding affinity evaluation was performed on the remaining molecules. Finally, twenty-eight compounds were selected for in vitro testing and eight compounds were determined to be low μM range RORγt inhibitors, thereby showing that the introduced VS protocol generated an effective hit rate of ~29%.
Enhancement of hMSC In Vitro Proliferation by Surface Immobilization of a Heparin-Binding Peptide
Authors: Cimino Maura , Parreira Paula , Leiro Victoria , Sousa Aureliana , Gonçalves Raquel M. , Barrias Cristina C. , Martins M. Cristina L.
Published: April 2023

The use of human Mesenchymal Stem Cells (hMSC) as therapeutic agents for advanced clinical therapies relies on their in vitro expansion. Over the last years, several efforts have been made to optimize hMSC culture protocols, namely by mimicking the cell physiological microenvironment, which strongly relies on signals provided by the extracellular matrix (ECM). ECM glycosaminoglycans, such as heparan-sulfate, sequester adhesive proteins and soluble growth factors at the cell membrane, orchestrating signaling pathways that control cell proliferation. Surfaces exposing the synthetic polypeptide poly(L-lysine, L-leucine) (pKL) have previously been shown to bind heparin from human plasma in a selective and concentration-dependent manner. To evaluate its effect on hMSC expansion, pKL was immobilized onto self-assembled monolayers (SAMs). The pKL-SAMs were able to bind heparin, fibronectin and other serum proteins, as demonstrated by quartz crystal microbalance with dissipation (QCM-D) studies. hMSC adhesion and proliferation were significantly increased in pKL-SAMs compared to controls, most probably related to increased heparin and fibronectin binding to pKL surfaces. This proof-of-concept study highlights the potential of pKL surfaces to improve hMSC in vitro expansion possible through selective heparin/serum protein binding at the cell-material interface.
Secondary Metabolites from Dendrobium nobile and Their Activities Induce Metabolites Apoptosis in OSC-19 Cells
Authors: Meng Yufan , Zhang Maosheng , Fang Yike , Yang Jianwen , Dong Minjian , Sun Chengxin , Xiao Shiji
Published: April 2023

To identify potential drug candidates, secondary metabolites of Dendrobium nobile were performed. As a result, two previously undescribed phenanthrene derivatives with a spirolactone ring (1 and 2), along with four known compounds, N-trans-cinnamoyltyramine (3), N-trans-p-coumaroyltyramine (4), N-trans-feruloyltyramine (5), and moscatilin (6), were isolated from Dendrobium nobile. The structures of the undescribed compounds were elucidated using NMR spectroscopy, electronic circular dichroism (ECD) calculations, and extensive spectroscopic data analysis. The cytotoxic effects of compounds on human tongue squamous cells OSC-19 were determined using MTT at concentrations of 2.5 μM, 5 μM, 10 μM, and 20 μM. Compound 6 exhibited potent inhibitory activity against OSC-19 cells with an IC50 of 1.32 μM. Migration assays and western blot assays demonstrated that compound 6 effectively inhibited migration by down-regulating MMP2 and MMP9 at concentrations of 0.5 μM and 1 μM. To investigate its effect on apoptosis, we performed AO/PI staining, flow cytometry, and WB experiments. The results showed that increasing concentrations led to increased red fluorescence, decreased green fluorescence, increased apoptosis rate, decreased expression of bcl-2, caspase 3, caspase 9, and parp proteins, and increased bax expression. Furthermore, the phosphorylation of JNK and P38 was activated, suggesting that compound 6 may induce apoptosis via the MAPK pathway.
Fusarium-Derived Secondary Metabolites with Antimicrobial Effects
Authors: Xu Meijie , Huang Ziwei , Zhu Wangjie , Liu Yuanyuan , Bai Xuelian , Zhang Huawei
Published: April 2023

Fungal microbes are important in the creation of new drugs, given their unique genetic and metabolic diversity. As one of the most commonly found fungi in nature, Fusarium spp. has been well regarded as a prolific source of secondary metabolites (SMs) with diverse chemical structures and a broad spectrum of biological properties. However, little information is available concerning their derived SMs with antimicrobial effects. By extensive literature search and data analysis, as many as 185 antimicrobial natural products as SMs had been discovered from Fusarium strains by the end of 2022. This review first provides a comprehensive analysis of these substances in terms of various antimicrobial effects, including antibacterial, antifungal, antiviral, and antiparasitic. Future prospects for the efficient discovery of new bioactive SMs from Fusarium strains are also proposed.
Plant Essential Oils as a Tool in the Control of Bovine Mastitis: An Update
Authors: Caneschi Alice , Bardhi Anisa , Barbarossa Andrea , Zaghini Anna
Published: April 2023

Bovine mastitis is a major concern for the dairy cattle community worldwide. Mastitis, subclinical or clinical, can be caused by contagious or environmental pathogens. Costs related to mastitis include direct and indirect losses, leading to global annual losses of USD 35 billion. The primary treatment of mastitis is represented by antibiotics, even if that results in the presence of residues in milk. The overuse and misuse of antibiotics in livestock is contributing to the development of antimicrobial resistance (AMR), resulting in a limited resolution of mastitis treatments, as well as a serious threat for public health. Novel alternatives, like the use of plant essential oils (EOs), are needed to replace antibiotic therapy when facing multidrug-resistant bacteria. This review aims to provide an updated overview of the in vitro and in vivo studies available on EOs and their main components as an antibacterial treatment against a variety of mastitis causing pathogens. There are many in vitro studies, but only several in vivo. Given the promising results of treatments with EOs, further clinical trials are needed.