bluuebunny/crossref_metadata_2025_split huggingface dataset:
Microorganism‐Derived Bisindole Alkaloids With Anticancer Potential and Their Mechanisms: A Comprehensive Review
Authors: Zhang Zi‐Long , Xu Hao‐Nan , Gong Chuan‐Ming , Li Yu‐Ze , Song Xiao‐Mei , Li Yi‐Ming , Zhang Dong‐Dong , Wang Rui 
Published: December 2024

ABSTRACTBisindole alkaloids constitute a significant class of natural compounds distinguished by their characteristic bisindole structure and renowned for their anticancer properties. Over the last six decades, researchers have isolated 425 microorganism‐derived bisindole alkaloids (MDBAs). Among them, 187 MDBAs have demonstrated anticancer properties against various in vitro cancer cell lines, primarily by impeding the cell cycle, restraining cell proliferation, and inducing apoptosis and autophagy. These effects are mediated by regulating key targets and signaling pathways such as hypoxia‐inducible factor (HIF)‐1, MAPK, and phosphatidylinositol 3‐kinase (PI3K)/AKT/mTOR. This review provides a comprehensive examination of the sources, chemical diversity, and anticancer properties of these compounds. Furthermore, it summarizes the structure–activity relationship (SAR), druggability, and the mechanisms underlying MDBAs’ anticancer effects. Ultimately, this article aims to furnish a thorough overview of the advancements in the investigation of microorganism‐derived bisindole alkaloids for their continued development and utilization.
Inhibition of Oral Biofilms and Enhancement of Anticancer Activity on Oral Squamous Carcinoma Cells Using Caffeine‐Coated Titanium Oxide Nanoparticles
Authors: Hussain Shaik Althaf , Ramasamy Mohankumar , Shaik Mohammed Rafi , Shaik Baji , Deepak Paramasivam , Thiyagarajulu Nathiya , Matharasi Antonyraj Anahas Perianaika , Guru Ajay 
Published: December 2024

ABSTRACTThe fungus Candida albicans is a prominent cariogenic fungal agent that works in association with Streptococcus mutans to accelerate the formation of oral cancer and tooth decay. This study evaluates caffeine‐encapsulated titanium oxide nanoparticles (CF‐TiO2 NPs) for their potential to prevent biofilm formation on teeth and enhance oral anticancer treatment by influencing apoptotic gene regulation. The synthesized CF‐TiO2 NPs were characterized using ultraviolet, scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, and Fourier‐transform infrared spectroscopy analyses, and their antioxidant activity was confirmed through free radical quenching studies. Antimicrobial efficacy was assessed using a zone of inhibition test, revealing strong activity against dental pathogens with a minimal inhibitory concentration of 80 µg/mL. Molecular docking using AutoDock explored interactions between CF and biofilm target sites, supporting their inhibitory potential. In vitro cytotoxicity studies on KB cancer cells showed a dose‐dependent increase in cytotoxic effects, with CF‐TiO2 NPs promoting apoptotic gene upregulation at concentrations of 20–160 µg/mL. CF‐TiO2 NPs demonstrated excellent antioxidant, antibacterial, and anticancer properties, showcasing their promise for oral therapeutic applications. This research highlights a novel approach to managing oral infections and associated complications while improving systemic oral health. Notably, this study is the first to report the biofilm‐inhibitory and anticancer potential of CF‐TiO2 NPs.
Essential Oil From Tetrapanax papyrifer (Hook.) K. Koch: Chemical Composition, Antioxidant Activity, α‐Glucosidase Inhibitory Effect Integrating Molecular Docking Analysis
Authors: Xu Ziyue , Zhu Jiadong , Gao Peizhong , Zhu Xinyu , Zhang Yusen , Liu Xu 
Published: December 2024

ABSTRACTThis study investigated the chemical composition of essential oil from Tetrapanax papyrifer and evaluated its antioxidant and anti‐α‐glucosidase activity. A total of 61 essential oil compounds from T. papyrifer were identified by gas chromatography‐mass spectrometry (GC‐MS) and gas chromatography‐flame ionization detector (GC‐FID). The essential oil is rich in sesquiterpenoids (96.05%), with major components identified as β‐cubebene (13.96%), caryophyllene (13.43%), α‐cubebene (12.12%), copaene (7.89%), δ‐cadinene (7.29%), eremophilene (6.15%), humulene (5.26%). The essential oil showed dose‐dependent antioxidant activity with IC50 values of 723.15 ± 24.10 and 200.74 ± 9.90 µg/mL for 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) and 2,2'‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS) assays, respectively. Ferric reducing antioxidant power (FRAP) antioxidant capacity was 222.73 ± 25.49 µmol/g. The essential oil exhibited a 17.86% ± 0.56% inhibitory effect against α‐glucosidase at 500 µg/mL. Moreover, in silico molecular docking analyses were utilized to validate the in vitro anti‐α‐glucosidase results further.
Novel Aminothiazole–Chalcone Analogs: Synthesis, Evaluation Acetylcholinesterase Activity, In Silico Analysis
Authors: Keçeci Sarıkaya Meryem , Yıldırım Şuheda , Kocyigit Umit M. , Ceylan Mustafa , Yırtıcı Ümit , Eyüpoğlu Volkan 
Published: December 2024

ABSTRACTIn this study, novel thiazole–chalcone analogs were synthesized, and their inhibitory effects on acetylcholinesterase (AChE) were examined. In vitro enzyme activity studies were conducted to calculate IC50 values, which were found to range between 2.55 and 72.78 µM (tacrine IC50 = 53.31 µM). The Ki values of the compounds showing the best inhibition (6g and 6e) were calculated and compared to those of the standard substance tacrine. All compounds reduced the AChE activity. Additionally, predictions made with SwissADME indicated that all compounds complied with Lipinski's rules and possessed good oral bioavailability properties, and the inhibitory effects of compounds 6e and 6g on AChE were evaluated using molecular docking and molecular dynamics simulations (100 ns). The results showed that compounds 6e and 6g had strong and stable interactions with AChE.
Magnolol as an Antibacterial Agent Against Drug‐resistant Bacteria Targeting Filamentous Temperature‐sensitive Mutant Z
Authors: Sun Ning , Deng Xin , Kong Hanqin , Zhi Ziling , Jiang Guli , Xiong Jing , Chen Sisi , Li Song , Yuan Wenchang , Wong Wing‐Leung 
Published: December 2024

ABSTRACTThe emergence of multiple drug‐resistant bacteria poses critical health threats worldwide. It is urgently needed to develop potent and safe antibacterial agents with novel bactericidal mechanisms to treat these infections. In this study, magnolol was identified as a potential bacterial cell division inhibitor by a cell‐based screening approach. This compound showed good antibacterial activity against a number of Gram‐positive pathogens (minimum inhibitory concentration 8–16 µg/mL) including methicillin‐resistant Staphylococcus aureus and vancomycin‐resistant Enterococcus. Further results obtained from biochemical experiments demonstrated that magnolol could markedly disrupt GTPase activity and filamentous temperature‐sensitive mutant Z (FtsZ) polymerization, consistent with the impediment to cell division in the bacteria tested. The in vivo antibacterial activity of magnolol was evaluated with a Galleria mellonella larvae model. The results showed that magnolol significantly increased the survival rate of larvae infected with methicillin‐resistant S. aureus. The interaction pattern of magnolol with FtsZ was investigated through molecular docking. The finding may offer meaningful insights into the mechanism of action of the compound. The results point to magnolol as a promising antimicrobial compound that inhibits cell division by affecting FtsZ polymerization and has the potential to be developed into an effective antimicrobial drug by further structure modification.
Chemical Profiling by High‐Performance Liquid Chromatography With Diode Array Detection and Gas Chromatography‐Mass Spectrometry Analysis and Antimicrobial Potential of Achillea santolina Plant Extracts against Extended‐Spectrum Beta‐Lactamase‐producing Escherichia coli and Fungal Pathogens
Authors: Renda Chahna , Nina Sadou , Amina Bouzana , Amina Bougouizi , Imane Haouame , Khellaf Rebbas , Garzoli Stefania , Bendif Hamdi 
Published: December 2024

ABSTRACTThe study examines the chemical composition and antimicrobial properties of petroleum ether and hydro‐methanolic extracts of Achillea santolina from Algeria. Chemical profiling was performed using high‐performance liquid chromatography with diode array detection for the hydro‐methanolic extract and gas chromatography‐mass spectrometry for the petroleum ether extract. Antibacterial and antifungal activities were evaluated using the disc diffusion method and broth dilution technique. Epicatechin (24.54 mg/g extract), and camphor (19.18%) were identified as main compounds in the hydro‐methanolic and petroleum ether extracts, respectively. Both extracts showed significant antibacterial effects against extended‐spectrum beta‐lactamase‐producing Escherichia coli strains, with inhibition diameters ranging from 10 to 13 mm, and minimum inhibitory concentration (MIC) values between 0.78 and 3.5 mg/mL. Anti‐fungal activity was also notable, particularly against Candida albicans, with an inhibition diameter of 14 mm, and MIC values between 0.39 and 1.56 mg/mL. The hydro‐methanolic extract showed up to 90% of growth inhibition against Aspergillus niger. These findings suggest that A. santolina could serve as a promising source of antimicrobial compounds to combat resistant pathogens.
Quantifying the Impact of High‐Pressure Processing on the Phenolic Profile, Antioxidant Activity, and Pollen Morphology in Honey
Authors: Scepankova Hana , Majtan Juraj , Pospiech Matej , Moreira Manuela M. , Pinto Carlos A. , Dias Luís G. , Estevinho Leticia M. , Delerue‐Matos Cristina , Saraiva Jorge A. 
Published: December 2024

ABSTRACTHoney can benefit from non‐thermal processing techniques such as high‐pressure processing (HPP) to improve its quality and bioactivity. This study investigated the impact of HPP (600 MPa for 5, 10, and 15 min) on honey's quality, including the levels of hydroxymethylfurfural (HMF), antioxidant activity, total phenolic content (TPC), and phenolic profile. HPP treatment did not significantly affect HMF or TPC levels but led to selective changes in the phenolic profile. Despite a reduction in certain phenolic compound content, HPP for 5 and 15 min caused a significant increase in the antioxidant activity (2,2‐diphenyl‐1‐picrylhydrazyl [DPPH]) of honey from the mean value of 41.8% to values of 45.4% and 49.6%, respectively. On the other hand, HPP for 10 min did not change the antioxidant activity of tested honey. A 27.5% reduction in the equatorial diameter of pollen grains was observed after HPP combined with temperature at 75°C, suggesting an improved release of bioactive compounds. The content of specific phenolic compounds, including caffeic acid, p‐coumaric acid, sinapic acid, naringin, kaempferol, and the TPC, significantly affected the DPPH activity. The increment in the antioxidant activity of HPP honey may be attributed to selective changes in the content of certain phenolic compounds and improved their extraction from pollen grains.
Characterisation of the Cytochrome P450 Monooxygenase CYP116B46 from Tepidiphilus thermophilus as a Homogentisic Acid Generating Enzyme and its Conversion to a Peroxygenase
Authors: Akter Jina , Lee Joel H. Z. , Whelan Fiona , De Voss James J. , Bell Stephen G. 
Published: December 2024

AbstractThe heme enzymes of the cytochrome P450 superfamily (CYPs) catalyse the selective hydroxylation of unactivated C−H bonds in organic molecules. There is great interest in applying these enzymes as biocatalysts with a focus on self‐sufficient CYP ‘fusion’ enzymes, comprising a single polypeptide chain with the electron transfer components joined to the heme domain. Here we elucidate the function of the self‐sufficient CYP116B46 fusion enzyme, from the thermophilic bacterium Tepidiphilus thermophilus. We demonstrate that it efficiently hydroxylates aromatic organic acids, exemplified by oxidation of 2‐hydroxyphenylacetic acid to homogentisic acid (2,5‐dihydroxyphenylacetic acid), an important metabolite in bacterial catabolism. In line with the thermophilic nature of the source bacterium, activity increased at higher temperatures, (50 °C), with a catalytic preference for NADPH over NADH. While self‐sufficient fusion enzymes simplify biocatalysis; engineered peroxygenase activity is also a key advance in the application of these enzymes as biocatalysts as it eliminates the need for electron transfer partner proteins and nicotinamide cofactors. We demonstrate that a T278E mutation in the heme domain of CYP116B46, confers peroxygenase activity. This engineered peroxygenase enzyme is stable to elevated temperatures and catalytic concentrations of hydrogen peroxide, with an observed optimal activity resulting in a total turnover number of ~650.
The Biarylitides: Understanding the Structure and Biosynthesis of a Fascinating Class of Cytochrome P450 Modified RiPP Natural Products
Authors: Padva Leo , Gullick Jemma , Coe Laura J. , Hansen Mathias H. , De Voss James J. , Crüsemann Max , Cryle Max J. 
Published: December 2024

AbstractThe biarylitides are a recently discovered class of RiPP natural products that are fascinating both from the small size of the core peptides as well as the diversity of peptide crosslinking exhibited by the cytochrome P450 enzymes found in these systems. In this review, we address the discovery and biosynthetic diversity of these systems and discuss the methods and challenges of analysing the structures of these constrained cyclic peptides. We also discuss the structures of the P450 enzymes involved in these pathways and address the potential for alternate catalytic outcomes and activities as seen most recently with the inclusion of biarylitide related enzymes within rufomycin biosynthesis.
Riboflavin with H2‐Driven or Electrochemical Recycling: A Cheap Cofactor System for Supporting Biocatalytic Alkene Reduction
Authors: Browne Lucy B. F. , Hancox Charlotte C. , Helin Sofia M. , Todd Peter M. T. , Vincent Kylie A. 
Published: December 2024

AbstractThis study shows that the organic cofactor riboflavin provides a cheap and atom‐efficient source of reducing equivalents to sustain biocatalytic alkene reductions by ene‐reductase enzymes, when coupled with a H2‐driven or electrochemical recycling system. We employ the robust NiFe hydrogenase, Escherichia coli Hyd1, for H2‐driven riboflavin reduction and show the feasibility of unmediated electrochemical recycling of reduced riboflavin at a simple carbon electrode. We show that H2‐driven reduction of riboflavin can be extended to continuous flow with a packed bed reactor comprising of Hyd1 immobilized on a carbon support. These findings demonstrate that there is scope for replacing the expensive nicotinamide cofactors—NADH or NADPH with riboflavin, for applications of ene‐reductases in biotechnology in either batch or continuous flow and in electrosynthesis.
Molecularly Defined Lubricant Hydrocarbons from Olefin Metathesis
Authors: Berkson Zachariah J. , Björgvinsdóttir Snædís , Barnes Alexander B. , Riek Roland , Schowner Roman , Buchmeiser Michael R. , Gibson Stephen , Price Gregory A. , Sunley Glenn J. , Copéret Christophe 
Published: December 2024

AbstractHydrocarbon‐based lubricants are ubiquitous in industrial applications but typically consist of complex mixtures of branched molecules that are challenging to characterize and to relate to their macroscopic properties. Consequently, lubricants are typically optimized empirically for specific applications by blending base oils with organic or inorganic additives. In this study, we report the synthesis and characterization of molecularly defined lubricants via metathesis of branched terminal olefins, followed by hydrogenation. The resulting saturated hydrocarbons are characterized by ultrahigh‐field (28.2 T) 1H and 13C NMR spectroscopies to establish their molecular structures and resolve different stereoisomers, showing the utility of state‐of‐the‐art spectroscopic tools for analyzing structures of branched alkanes. Furthermore, the molecular‐level diffusion and bulk viscosity properties compare favorably to classical synthetic lubricants based on hydrogenated polyalphaolefin (PAO) blends, establishing olefin metathesis as a selective and scalable route to high‐performance lubricant oils with defined molecular structures.
PtNi Nanorods Catalysts Prepared by Magnetron Sputtering for Alkaline Hydrogen Evolution Reaction
Authors: Tian Jinsen , Qin Junhao , Zhang Hao , Tang Mingwei , Shen Jun 
Published: December 2024

AbstractThe development of cost‐effective and highly efficient catalysts for the hydrogen evolution reaction (HER), particularly in alkaline environments, is a critical challenge for hydrogen applications. One promising approach involves the alloying of noble metals with transition metals. This study presents the synthesis of PtNi nanorod catalysts, characterized by a thickness of 500 nm, which were fabricated via magnetron sputtering onto nickel foam. When evaluated in a 1 M KOH electrolyte, the Pt–Ni alloy demonstrates superior HER performance compared with both Ni and Pt, exhibiting an overpotential of 35 mV at 10 mA/cm2 and a Tafel slope of 29 mV/dec. The enhanced catalytic activity is attributed to several factors, including a high electrochemically active surface area, increased mass activity, elevated turnover frequency, and reduced electrochemical impedance. Furthermore, the Pt–Ni catalyst maintains remarkable stability at a current density of 10 mA/cm2 over a duration of 100 h. The improved HER performance is ascribed to the nanorod architecture, which features a high density of grain boundaries, as well as the synergistic interactions between Ni and Pt.
Oxygen‐Vacancy Rich Co3O4/CeO2 Interface for Enhanced Oxygen Reduction and Evolution Reactions
Authors: Patowary Suranjana , Watson Amber , Chetry Rashmi , Sudarsanam Putla , Russell Andrea E. , Bharali Pankaj 
Published: December 2024

AbstractOxygen reduction and evolution reactions (ORR and OER, respectively) are the two most extensively studied reactions in electrochemistry. Herein, we report the synthesis of Co3O4/CeO2/GNP (GNP = graphene nanoplatelet) electrocatalyst for ORR and OER that exhibits an early onset potential (0.85 V) and half‐wave potential (E1/2) of 0.69 V for ORR. The reported catalyst is highly durable with 87.6% retention of its initial current after a 6 h chronoamperometry test compared to 72.5% by Pt/C. It exhibits a negligible shift of E1/2 after 10,000 potential cycles for ORR. Heterogeneous oxide/oxide interfaces, oxygen vacancies and semicrystalline nature are inferenced to play a dominant role in altering the collective catalytic efficiency of Co3O4/CeO2/GNP. High concentration of oxygen vacancy defects (68%) in Co3O4/CeO2/GNP is presumed to play a dominant role here. The catalyst is bifunctional for ORR and OER with a bifunctionality index of 0.98 V and operates at an overpotential of ƞ10 = 440 mV for OER. Ex situ X‐ray absorption studies indicate an increased average oxidation state of Co by 15% in Co3O4/CeO2/GNP compared to Co3O4/GNP, aiding in preserving its inherent catalytic nature of spinel Co3O4.
Development of Bifunctional Catalysts for CO2 Capture and Conversion at Low Temperatures Under an Electric Field
Authors: Tomozawa Keidai , Tsunoji Nao , Suwa Rin , Sadakane Masahiro , Ueda Tadaharu , Ogo Shuhei 
Published: December 2024

AbstractSystems for direct conversion of captured CO2 into CO (i.e., CO2 capture and reduction: CCR) via bifunctional catalysts have attracted attention as technologies for achieving carbon neutrality. However, the reported systems require additional heating above 623 K, which is still an issue from an ecological perspective. The present work realized selective CO production through CCR under isothermal conditions at 423 K by the application of a direct current electric field and a Pt‐Na/TiO2 catalyst. The application of an electric field to the catalyst is needed for CO2 conversion at low temperature, and the loading of both Pt and Na is required for CO2 capture and its selective reduction to CO. The obtained results open the door for greener CCR technologies that effectively utilize waste heat from power plants and industry.
A One‐Pot Biocatalytic Cascade to Access Diverse l‐Phenylalanine Derivatives from Aldehydes or Carboxylic Acids
Authors: Anderson Shelby R. , Gopal Madan R. , Spangler Abigail P. , Jones Michaela A. , Wyllis D'Jana R. , Kunjapur Aditya M. 
Published: December 2024

AbstractNonstandard amino acids (nsAAs) that are l‐phenylalanine derivatives with aryl ring functionalization have long been harnessed in natural product synthesis, therapeutic peptide synthesis, and diverse applications of genetic code expansion. Yet, to date, these chiral molecules have often been the products of poorly enantioselective and environmentally harsh organic synthesis routes. Here, we reveal the broad specificity of multiple natural pyridoxal 5′‐phosphate (PLP)‐dependent enzymes, specifically an l‐threonine transaldolase, a phenylserine dehydratase, and an aminotransferase, toward substrates that contain aryl side chains with diverse substitutions. We exploit this tolerance to construct a one‐pot biocatalytic cascade that achieves high‐yield synthesis of 18 diverse l‐phenylalanine derivatives from aldehydes under mild aqueous reaction conditions. We demonstrate the addition of a carboxylic acid reductase module to this cascade to enable the biosynthesis of l‐phenylalanine derivatives from carboxylic acids that may be less expensive or less reactive than the corresponding aldehydes. Finally, we investigate the scalability of the cascade by developing a lysate‐based route for preparative‐scale synthesis of 4‐formyl‐l‐phenylalanine, a nsAA with a bio‐orthogonal handle that is not readily market‐accessible. Overall, this work offers an efficient, versatile, and scalable route with the potential to lower manufacturing costs and democratize synthesis for many valuable nsAAs.
BiVO4‐Based Photoelectrochemical Water Splitting
Authors: Yi Qinghua , Wang Hao , Lee Jong‐Min 
Published: December 2024

AbstractPhotoelectrochemical water splitting is one of the most promising and appealing strategies for converting sunlight into sustainable hydrogen energy and has received increasing attention. Among the potential photocatalysts, BiVO4 has attracted particular attention as a photoanode material because of its appropriate bandgap (2.4 eV) and favorable band‐edge position. Moreover, its carrier mobility and hole‐diffusion length are modest, and the photocurrent density is below the theoretical expectation (7.5 mA cm−2). Recently, diverse strategies have been developed to improve the performance of BiVO4‐based photoanodes with rapid progress. In this article, engineering strategies including facet tailoring, intrinsic and extrinsic doping, surface modification, are summarized, and remaining challenges and perspective for the future research are provided.