Journal of Molecular Structure最新文献

{"title":"Novel palladium(II) complexes of dipodal bis(1,3,4-oxadiazole-5-thione) ligands: Syntheses, characterization, in vitro antiproliferative activity, DNA binding interactions, and theoretical insights","authors":"Somayeh Karami,&nbsp;Mitra Ghassemzadeh,&nbsp;Mahboube Eslami Moghadam,&nbsp;Farshid Mohsenzadeh","doi":"10.1016/j.molstruc.2025.142160","DOIUrl":"10.1016/j.molstruc.2025.142160","url":null,"abstract":"<div><div>The synthesis of two new palladium complexes of dipodal 2-mercapto-1,3,4-oxadiazole derivatives, [<strong>L1</strong>PdCl₂]₂ (<strong>C1, L1</strong>: 1,3-<em>bis</em>(5-thio-1,3,4-oxadiazol-2-<em>yl</em>)benzene, and [<strong>L2</strong>PdCl₂]₂ (<strong>C2, L2:</strong> 1,4-<em>bis</em>(5-thio-1,3,4-oxadiazol-2-<em>yl</em>)benzene have been reported. Both complexes were characterized by using a series of techniques including elemental analysis, ATR-IR, FAR-IR, ¹H and ¹³C NMR spectroscopy, ESI- and HR-MS spectrometry, UV–Vis spectroscopy, and XPS analysis. The <em>in vitro</em> biological anticancer activity of palladium(II) complexes and their related ligands against human breast cancer cell line (MCF-7) and the human breast normal cell line (MCF-10A) has been investigated. According to the antiproliferation assays, complexes <strong>C1</strong> and <strong>C2</strong> (IC₅₀ 75 ± 4 µМ and 88 ± 2 µМ, respectively) exhibited higher antitumor activity compared to their corresponding ligands (IC₅₀ values of 181 ± 15 µМ for <strong>L1</strong> and 192 ± 11 µМ for <strong>L2</strong>). Both palladium(II) complexes exhibited low toxicity (≥180 μM) against the MCF-10A normal cell line. The cytotoxic efficiency of <strong>C1</strong> was compared to that of the anticancer drug oxaliplatin. Density functional theory (DFT) calculations were performed to predict the chemical reactivity of the synthesized compounds. Furthermore, the mode of binding of <strong>L1, L2, C1</strong> and <strong>C2</strong> with DNA was investigated using electronic absorption monitoring, viscosity measurements, and molecular docking simulations. These investigations suggest that both ligands and complexes bind to DNA within the minor grooves. The results indicated that amide nitrogen, ether oxygen, thionic sulfur, and chlorine atoms as well as the aromatic rings of the ligands and their complexes are responsible for their groove binding and intercalation to DNA <strong>1BNA</strong> and DNA <strong>1Z3F</strong> conformations.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1337 ","pages":"Article 142160"},"PeriodicalIF":4.0,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143737941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Using multi-spectroscopic techniques to evaluate photophysical, photobiological and bio-interactive properties of meso‑5,15-bis(substituted)porphyrins","authors":"Rafaela C. Copello ,&nbsp;Bruna M. Rodrigues ,&nbsp;Henrique F.V. Victória ,&nbsp;Klaus Krambrock ,&nbsp;Otávio A. Chaves ,&nbsp;Paulo C. Piquini ,&nbsp;Bernardo A. Iglesias","doi":"10.1016/j.molstruc.2025.142175","DOIUrl":"10.1016/j.molstruc.2025.142175","url":null,"abstract":"<div><div>The use of <em>trans</em>-substituted porphyrins with the most diverse substituents in the <em>meso</em>‑aryl positions of the macrocycle is reported. The photophysical behavior of these porphyrins were studied using multi-spectroscopic techniques, both in the ground and excited states, as well as theoretical calculations, e.g., natural transitions orbitals (NTOs) analysis). Photobiological data such as photostability, hydrophilicity (log <em>P</em>_OW), and ROS-producing (singlet oxygen and superoxide species) were also evaluated by classical analysis and electron paramagnetic resonance spectroscopy (EPR) spin trap assays. Finally, interactive profile with bovine serum albumin (BSA) and calf-thymus deoxynucleic acid (CT-DNA) was in vitro and in silico evaluated, revealing the ability of each <em>meso</em>‑5,15-porphyrin derivative to interact with these biomacromolecules.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1337 ","pages":"Article 142175"},"PeriodicalIF":4.0,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143747740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis of furan-based pyrazoline as an anticancer agent: An in vitro and in silico approach toward COX-2 inhibition","authors":"Tegar Asanda Ghifari ,&nbsp;Fia Fathiana Wulan ,&nbsp;Endang Astuti ,&nbsp;Venty Suryanti ,&nbsp;Daratu Eviana Kusuma Putri ,&nbsp;Hadi Nur ,&nbsp;Tutik Dwi Wahyuningsih","doi":"10.1016/j.molstruc.2025.142125","DOIUrl":"10.1016/j.molstruc.2025.142125","url":null,"abstract":"<div><div>Pyrazoline is a versatile heterocyclic compound known for its easy synthesis and structural modification, making it an excellent framework for enhancing biological activity. The incorporation of additional heterocyclic systems, such as furan, has significantly improved its anticancer potential, offering a promising avenue for developing new therapeutic agents. In this study, furan-based pyrazoline derivatives were synthesized <em>via</em> reflux using chalcone intermediates. Their structures were confirmed by gas chromatography–mass spectrometry (GC–MS), Fourier transform infrared (FTIR), proton and carbon nuclear magnetic resonance (¹H- and ¹³C-NMR) spectroscopy. The anticancer activities of eight pyrazoline derivatives (<strong>4a–4h</strong>) were investigated using the MTT assay against HeLa, WiDr, MCF-7, and T47D cancer cell lines, with normal Vero cells as a control to evaluate their selectivity. Among these compounds, 3-(furan-2-yl)-5-(4-methoxyphenyl)-1-phenyl-4,5-dihydro-1H-pyrazole (<strong>4d</strong>) demonstrated the best anticancer activity, with half-maximal inhibitory concentration values of 1.07 and 2.25 µg/mL against HeLa and WiDr cells, respectively, and a selectivity index &gt; 100. Molecular docking analysis of <strong>4d</strong> with cyclooxygenase-2 revealed a binding affinity of −9.7 kcal/mol. Thus, further molecular dynamics simulations confirmed stable interactions with the formation of persistent hydrogen bonds with the Ser530 residue. Pharmacokinetic predictions indicated good absorption and distribution profiles, although <strong>4d</strong> is probably metabolized by the CYP3A4 enzyme in the liver. These findings suggest that compound <strong>4d</strong> is a promising lead compound for further development as a selective anticancer agent.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1337 ","pages":"Article 142125"},"PeriodicalIF":4.0,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143734845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cytostatic anticancer activity of novel C^N^N platinum (II) carbene-containing complexes – New mitochondrial uncouplers","authors":"Maria D. Tokhtueva ,&nbsp;Vladislav M. Abramov ,&nbsp;Vsevolod V. Melekhin ,&nbsp;Ekaterina S. Sheina ,&nbsp;Sergey L. Deev ,&nbsp;Oleg S. Eltsov","doi":"10.1016/j.molstruc.2025.142158","DOIUrl":"10.1016/j.molstruc.2025.142158","url":null,"abstract":"<div><div>In this work, we lead to the appearance of novel carbene-containing C^N^N platinum (II) complexes of arylbipyridines. This paper describes the synthesis, structure properties, and outcomes of an <em>in vitro</em> cytotoxicity research. The synthesized metal complexes exhibit broad anticancer efficacy against cell lines such as human glioblastoma A172, lung carcinoma A549 and liver carcinoma HepG2. The average inhibitory doses obtained using the MTT test are many times greater than the Cisplatin activity concentrations currently used in medical practice. The experiment involving Annexin V-FITC and propidium iodide revealed that apoptotic processes of cell death were not induced. Additionally, several platinum complexes were found to have a strong cytostatic impact and to impede replication. It was discovered that novel compounds containing carbenes result in a reduction in mitochondrial potential equivalent to that of the positive control when cells were stained with JC-1 dye. We have found that the main antitumor mechanism of action of platinum complex compounds is due to a complete drop in potential on mitochondria and a slowdown in cell division.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1337 ","pages":"Article 142158"},"PeriodicalIF":4.0,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A pyrene-based fluorescent probe for cysteine detection in the presence of other biothiols and its application in living cells","authors":"Mengzhou Wang,&nbsp;Jiayao Du,&nbsp;Yuefeng Ye,&nbsp;Guangzhou Lin,&nbsp;Chengyuan Liang,&nbsp;Wei Liu","doi":"10.1016/j.molstruc.2025.142095","DOIUrl":"10.1016/j.molstruc.2025.142095","url":null,"abstract":"<div><div>A novel fluorescent probe (<em>E</em>)-3-(pyrazin-2-yl)-1-(pyren-1-yl)prop‑2-en-1-one, (<strong>PPP</strong>), which pyrene structure attached to pyrazine derivative, was designed for detection of cysteine (Cys) since it plays an important role in many physiological and pathological processes. The results indicated that probe <strong>PPP</strong> could monitor Cys in the presence of other biothiols such as glutathione (GSH) and homocysteine (Hcy) under mild conditions. Furthermore, the probe <strong>PPP</strong> was successfully applied for cellular imaging and specific fluorescence detection of Cys in TE-1 cells with negligible cytotoxicity, which also helps to further understand the pathological process of related diseases.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1337 ","pages":"Article 142095"},"PeriodicalIF":4.0,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143737944","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis of novel α-carboxylate-β-bismethylsulfanyl pyrazolyl Schiff base derivatives: Targeting DNA gyrase in antibacterial activity","authors":"Ankita Garg ,&nbsp;Dolar Dureja ,&nbsp;Anjali Vijeata ,&nbsp;Ganga Ram Chaudhary ,&nbsp;Shiwani Berry ,&nbsp;Savita Chaudhary ,&nbsp;Aman Bhalla","doi":"10.1016/j.molstruc.2025.141954","DOIUrl":"10.1016/j.molstruc.2025.141954","url":null,"abstract":"<div><div>Microbial infections pose a significant threat to human health, often necessitating the use of potent antimicrobial agents for treatment. In this study, a novel series of α-carboxylate-β-<em>bis</em>methylsulfanyl pyrazolyl Schiff base derivatives <strong>6a-d</strong> were synthesized and characterized through a combination of analytical techniques, including FT-IR, ¹H and ¹³C NMR, mass spectrometry and single-crystal X-ray crystallography. Through crystallographic scrutiny, it was unveiled that α-carboxylate-β-bismethylsulfanyl pyrazolyl aldehyde <strong>5</strong> is adopted in a monoclinic I2/a space group, while its Schiff base <strong>6c</strong> is crystallized in the orthorhombic Pbca space group. The synthesized Schiff base derivatives <strong>6a</strong>-<strong>d</strong> were subsequently assessed for their antibacterial efficacy targeting DNA gyrase protein against one gram-positive bacterium (<em>Staphylococcus aureus</em> MTCC-1430) and three gram-negative bacteria (<em>Escherichia coli</em> MTCC-1610, <em>Pseudomonas aeruginosa</em> MTCC-1934, and <em>Salmonella typhi</em> MTCC-3216). All compounds had substantial antibacterial efficacy against all bacterial strains; however, compound <strong>6b</strong> exhibited noticeable efficacy against all gram-negative strains, whereas compound <strong>6d</strong> disclosed the highest antibacterial potential against gram-positive strains. The electronic characteristics of the compounds were analysed utilizing density functional theory (DFT), focusing on the determination of HOMO-LUMO energy gaps, molecular electrostatic potential (MEP) maps, and global reactivity descriptors. Molecular docking studies reinforced the promising antibacterial potential of these Schiff base derivatives, revealing favourable binding interactions of the Schiff base derivatives with bacterial target proteins. Additionally, drug-likeness and toxicity assessments were conducted to determine the suitability of these compounds as potential therapeutic agents. Based on these findings, it is suggested that the synthesized derivatives could serve as a promising scaffold for the advancement of novel antibacterial therapies.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1337 ","pages":"Article 141954"},"PeriodicalIF":4.0,"publicationDate":"2025-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143726198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High energy density with low mechanical sensitivity: A novel energetic cocrystal composed of CL-20 and FOX-7 obtained by electrostatic spray method","authors":"Guiyun Hang,&nbsp;Jintao Wang,&nbsp;Tao Wang,&nbsp;Haijian Xue,&nbsp;Huiming Shen,&nbsp;Wenli Yu","doi":"10.1016/j.molstruc.2025.142138","DOIUrl":"10.1016/j.molstruc.2025.142138","url":null,"abstract":"<div><div>Cocrystallization technique is an effective strategy to tune performances of materials and it has been proved to be a novel and promising approach to decrease mechanical sensitivity and improve physicochemical properties of energetic compounds. In this work, based on the high energy density compound 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12- hexaazaisowurtzitane (CL-20) and insensitive energetic compound 1,1-diamino-2,2-dinitroethylene (FOX-7), a novel CL-20/FOX-7 cocrystal (molar ratio 1:1) was prepared by electrostatic spray method and the crystal structure, thermal behavior, mechanical sensitivity and energetic property were characterized and the intermolecular interaction was analyzed. Scanning electron microscopy (SEM) reveals that the cocrystal has smooth crystal surface, the particle size is within 1 μm∼5 μm, and the crystal morphology is different from CL-20 and FOX-7. Powder X-ray diffraction (PXRD) indicates that a new substance is formed between CL-20 and FOX-7. Fourier transform infrared spectroscopy (FT-IR) illustrates that the absorption peaks in cocrystal is shifted from 5 cm⁻¹ to 10 cm⁻¹, meaning that intermolecular interaction is formed. Differential scanning calorimetry (DSC) results declares that the melting point of cocrystal is 7.5 °C higher than FOX-7, while the thermal decomposition temperature is decreased by 7.0 °C. The mechanical sensitivity indicates that compared with raw CL-20, the impact sensitivity of CL-20/FOX-7 cocrystal is decreased by 64 %, drop height is increased by 31 cm and friction sensitivity is decreased by 68 %. The predicted crystal density, and detonation parameters of CL-20/FOX-7 energetic cocrystal are 1.928 g/cm³, 9178 m/s, 40.44 GPa, these parameters are higher than HMX, implying that this cocrystal has high energy density. The intermolecular interactions in CL-20/FOX-7 cocrystal mainly include hydrogen bonding and van der Waals (vdW) forces. Therefore, the CL-20/FOX-7 cocrystal is a novel energetic material with high energy density and low mechanical sensitivity, and it has wide application prospect in the near future.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1336 ","pages":"Article 142138"},"PeriodicalIF":4.0,"publicationDate":"2025-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143705258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthetic strategies, biological and computational screening of thiadiazole bearing benzothiazole derivatives as prospective anti-diabetic agents","authors":"Rafaqat Hussain ,&nbsp;Shoaib Khan ,&nbsp;Asma Sardar ,&nbsp;Liaqat Rasheed ,&nbsp;Mohammad Shahidul Islam ,&nbsp;Tahani Mazyad Almutairi","doi":"10.1016/j.molstruc.2025.142141","DOIUrl":"10.1016/j.molstruc.2025.142141","url":null,"abstract":"<div><div>This study explores the synthesis and biological evaluation of novel thiadiazole bearing benzothiazole derivatives as potential dual inhibitors of α-amylase and α-glucosidase enzymes critical in carbohydrate metabolism. Inhibiting these enzymes offers a promising therapeutic strategy for managing postprandial hyperglycemia in type 2 diabetes. A series of imidazopyridine-derived thiadiazole bearing benzothiazole derivatives (<strong>1–18</strong>) were synthesized and were also structurally elucidated through ¹H NMR, ¹³C NMR and HREI-MS analysis. These derivatives were subjected to in vitro enzyme inhibition assays, revealing significant inhibitory activities with IC₅₀ values ranging from 12.20 ± 2.70 to 46.90 ± 6.60 µM for α-amylase, and from 12.50 ± 1.90 to 48.60 ± 6.80 µM for α-glucosidase. These results were compared with the standard drug Acarbose, which exhibited IC₅₀ values of 32.40 ± 2.30 µM for α-amylase and 35.70 ± 2.70 µM for α-glucosidase. Notably, compounds 13, 10, 9, 7 and 3 displayed the most potent inhibition against both α-amylase and α-glucosidase. Additionally, molecular docking studies were conducted to predict binding interactions between the synthesized derivatives and the active sites of α-amylase and α-glucosidase. The in-silico results corroborated the in vitro findings, showing strong binding affinities and interaction patterns, suggesting these derivatives as promising candidates for further development in antidiabetic therapy.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1337 ","pages":"Article 142141"},"PeriodicalIF":4.0,"publicationDate":"2025-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143734781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel bisazo dyes with Schiff bases: Synthesis, characterization, dyeing of polyester fabric, antimicrobial activity, and DFT studies","authors":"Ola A. Abu Ali ,&nbsp;Hossa F. Al Shareef ,&nbsp;Rasha Felaly ,&nbsp;Ali A. Ali ,&nbsp;M.M. Elsawy ,&nbsp;Amany Belal ,&nbsp;Reem I Alsantali ,&nbsp;Ahmed B.M. Mehany ,&nbsp;S.M. Al-Shomar ,&nbsp;N.S. Abdelshafi ,&nbsp;Walid E. Elgammal","doi":"10.1016/j.molstruc.2025.142075","DOIUrl":"10.1016/j.molstruc.2025.142075","url":null,"abstract":"<div><div>The study's primary objective was to create novel bis-azo-disperse dyes bearing Schiff bases based on a sulfonamide-pyridine group using a traditional azo coupling reaction. The dye structures were identified through infrared, ¹H/¹³C NMR analysis, and mass spectroscopy. The main goal of the study was to optimize dyeing, factors, including pH, temperature, time, and shade, to understand how disperse dyes <strong>12–14</strong> behave when dyeing polyester fabrics. Raising the dyeing temperature from low to high (90 °C to 130 °C) increased color strength (K/S) values in polyester fabrics treated with the produced dispersion dyes. The produced azo dyes were applied to polyester fabrics at a depth of 2 % using high-temperature pressure in water, with Kimi-levelling PS acting as a leveling and dispersion agent. The colored polyester samples exhibited different shades ranging from beige to yellowish brown to dark brown, depending on the coupler moieties. Additionally, the effect of substituents on the colorimetric colors (CILAB) and color strength (K/S) measurements of dyed polyester fabrics was investigated. Moreover, the use of these dyes protects bacteria in the environment, where dyes demonstrate high effectiveness as antibacterial agents against certain types of bacteria. DFT parameters associated with experimental data.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1337 ","pages":"Article 142075"},"PeriodicalIF":4.0,"publicationDate":"2025-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring the dual aspects of Sapindus mukorossi pod as a novel sustainable biosurfactant-based corrosion inhibitor for carbon steel in saline environment: An experimental and theoretical insights","authors":"Monisha Ravi,&nbsp;Abigail Jennifer G,&nbsp;Elumalai Varathan,&nbsp;Arockia Selvi J","doi":"10.1016/j.molstruc.2025.142065","DOIUrl":"10.1016/j.molstruc.2025.142065","url":null,"abstract":"<div><div>In this study, a novel application of the ethanolic extract of <em>Sapindus mukorossi</em> pod (SmPE) was investigated as a biosurfactant-based corrosion inhibitor for carbon steel (CS) against both electrochemical and microbiologically influenced corrosion (MIC) in a saline medium (3.5 % NaCl). Gas chromatography-mass spectrometry (GC–MS) identified cis-vaccenic acid as the primary active phytochemical in SmPE, which acts as a biosurfactant molecule. The corrosion inhibitive performance of SmPE on CS was evaluated with varying concentrations ranging from 50<span><math><mo>−</mo></math></span>400 ppm by gravimetric analysis and electrochemical techniques such as Electrochemical Impedance Spectroscopy (EIS) and Potentiodynamic Polarization (PDP). The results revealed that inhibition efficiency (IE %) increased with SmPE concentration, reaching a maximum of 96.9 % at the critical micelle concentration (CMC) of 250 ppm, accompanied by a minimal corrosion rate (CR) of 0.0062 mm/y. The CMC was confirmed by a distinct change in electrochemical parameters at this concentration. PDP analysis indicated that SmPE functions as a mixed-type inhibitor. Surface characterization via Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM-EDX), Fourier Transform Infrared Spectroscopy (FT-IR), Atomic Force Microscopy (AFM), and X-ray Photoelectron Spectroscopy (XPS) confirmed the adsorption of SmPE molecules on the CS surface. Ultraviolet-visible (UV–vis) spectroscopy demonstrated complex formation between Fe²⁺ ions and the inhibitor. Density Functional Theory (DFT) calculations provided a theoretical understanding of the inhibitor's interaction with the CS surface. Additionally, SmPE exhibited notable biocidal activity against MIC, with a biocidal efficiency (BE %) of 94.40 ± 0.90 % at 250 ppm, as determined by Colony Forming Units (CFU) assay.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1337 ","pages":"Article 142065"},"PeriodicalIF":4.0,"publicationDate":"2025-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143747739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}