Bioactivity Studies Research Articles

Chemotaxonomy and Bioactive Potential of High-Mountain Plantago atrata.

Plantago atrata Hoppe is a high-altitude mountain plant exposed to harsh environmental factors. This study aims to elucidate the ecological, phytochemical and pharmacological characteristics of this lesser-known plantain. Despite nutrient-poor peat soil, the leaves of P. atrata contained increased levels of phosphorus, potassium and calcium, and the anatomy revealed an isobilateral mesophyll. Molecular taxonomic identification and phylogenetic analyses confirmed the classification of the studied plant as P. atrata and its clustering with narrow-leaved plantains growing in extreme conditions. Detailed phytochemical profiles revealed primary and secondary metabolites that can be used as taxonomic identifiers and for bioactivity studies. The methanol fraction enriched in phenolic compounds appeared biologically active - by displaying limited antimicrobial activity, however, it possessed significant radical-scavenging and anti-inflammatory capacity. The data demonstrate that P. atrata's leaf parameters and phytochemical arsenal assure plant survival and reveal the plantain's pharmaceutical potential in inhibiting inflammation via the classical pathway of Complement activation.

Expression, characterization and anti-colon cancer activity of recombinant ginseng peptides with amino acid tandem repeats.

Ginseng peptides, small molecule active ingredients in ginseng, are mainly extracted naturally or synthesised chemically, but high costs and difficulties hinder further research. In this study, a ginseng hexapeptide FKEHGY, named antitumor peptide 0601 (AT0601) and its five tandem sequence repeats AT0605, were expressed in Bacillus subtilis WB600 for the first time, and the bioactivity study showed that the anticancer activity of AT0605 was even significantly higher than that of AT0601 for colon cancer CT26 cells, with IC50s of 16.82±1.3 μM (48 h) and 855.57±6.04 μM (48 h), respectively, i.e. AT0605 achieves the same inhibition rate for CT26 cells at a concentration 50 times lower than that of AT0601. Similar to the ginseng peptide AT0601, recombinant AT0605 also inhibited cell growth by blocking cells in the G1 phase and activated the mitochondria-associated caspase pathway to induce apoptosis. In conclusion, all two kinds of the recombinant ginseng peptides could also inhibit cell proliferation through mechanisms such as inhibiting cell cycle arrest and inducing a decrease in mitochondrial membrane potential.

Zinc Doped Akermanite: A Promising Biomaterial for Orthopedic Application with Enhanced Bioactivity, Mechanical Strength, and Bacterial Study.

Incorporating zinc into biocompatible materials has been identified as a potential strategy for promoting bone regeneration and osteogenic activity during hard tissue regeneration. This work aimed to investigate the impact of zinc doping on the structure of akermanite, which was synthesized using the sol-gel combustion method, with the goal of improving the biological response. Powder XRD and FT-IR analysis confirmed the phase purity and the respective functional groups associated with Zn-doped akermanite. Further XPS analysis confirmed the presence of zinc with the respective binding energies in the akermanite matrix. According to the results obtained from the analysis, the apatite-forming ability of Zn-doped akermanite demonstrated enhanced apatite deposition on the surface of the pellet after 9 days of immersion in the SBF medium. The measured mechanical parameters, including compressive strength (140-189 MPa) and Young's modulus (2505-3599 MPa), fall within the range of human cortical bone. Antimicrobial results showed an improved inhibition rate of the doped ceramics compared to pure akermanite with an inhibition percentage of 87% even at lower concentrations. The hemocompatibility of the materials showed hemolysis of human blood cells within the acceptable range without exhibiting toxicity. Cytotoxicity results demonstrate the biocompatibility of the materials with the MG-63 cell line. Based on the results, akermanite doped with zinc at optimal concentrations was found to be compatible and nontoxic promoting it as a potential alternative for bone regeneration in orthopedic applications.

Phosphorus-nitrogen compounds. Part 77. The synthesis of novel ferrocenyl(N/O)spiro- and 2-cis-4-dichloro-ferrocenyl(N/O)ansa-cyclotetraphosphazenes with 9-ethyl-3-carbazolyl pendant arm(s): spectral, bioactivity, electrochemical and dye-sensitized solar cell fabrication studies

Herein, the reactions of octachlorocyclotetraphosphazene (OCCP, 1) with sodium-3-ferrocenylmethyl-amino)-1-propanoxide (L1) gave hexachloro-ferrocenyl-(N/O)-spiro-2 and 2-cis-4-dichloro-ferrocenyl-(N/O)-ansa-3 cyclotetraphosphazenes in THF. Spiro- (2) reacted with excess 9-ethyl-N-methyl-3-carbazolyl-1,3-diaminopropane (L2) and 9-ethyl-N-ethyl-3-carbazolyl-1,2-diaminoethane (L3) to produce 2-trans-6-dispiro ( dispiro-2a) and 2-trans-4-cis-6-trans-8-tetraspiro ( tetraspiro-2b) cyclotetraphosphazenes, respectively. The reactions of ansa-3 with excess L2 led to the formation of monospiro {2-cis-4-dichloro-ansa-2-trans-6-spiro(N/N) ( ansa-spiro-3b)} and dispiro {2-cis-4-dichloro-ansa-6-trans-8-dispiro(N/N) ( ansa-dispiro-3b)} cyclotetraphosphazenes. However, the reactions of ansa-3 with excess 9-methyl-N-ethyl-3-carbazolyl-1,2-diaminomethane (L4) afforded 2-cis-4-dichloro-ansa-6-trans-8-dispiro(N/N) ( ansa-dispiro-3a). Ansa-3 was also reacted with excess sodium 3-(9-ethyl-carbazolamino)-1-propanoxide (L5) to give 2-cis-4-dichloro-ansa-2-trans-6-spiro(N/O) ( ansa-spiro-3c) and 2-cis-4-dichloro-ansa-6-trans-8-dispiro(N/O) ( ansa-dispiro-3c) cyclotetraphosphazenes. Reactions were carried out by classical and microwave-assisted methods. These novel multi-heterocyclic inorganic/organic hybrid cyclotetraphosphazenes can offer valuable insights into developing new materials. Tetraspiro-2b and all ansa compounds have more than one stereogenic P-atom. The optical and electrochemical properties of some cyclotetraphosphazenes were investigated using UV-vis absorption and cyclic voltammetry (CV) techniques. As a result, these phosphazenes can be suggested as ferrocene-based charge transformable structures. They can be used as new-generation and synergistic dye-sensitized solar cell (DSSC) materials. Additionally, antimicrobial activities of five compounds ( dispiro-2a, ansa-spiro-3b, ansa-dispiro-3b, ansa-spiro-3c and ansa-dispiro-3c) against various pathogenic bacteria and yeasts were evaluated. Their interactions with pBR322 plasmid DNA were also investigated.

The Synthesis, Crystal Structure, Modification, and Cytotoxic Activity of α-Hydroxy-Alkylphosphonates.

A series of α-hydroxy-alkylphosphonates and α-hydroxy-alkylphosphine oxides were synthesized by the Pudovik reaction of acetaldehyde and acetone with dialkyl phosphites or diarylphosphine oxides. The additions were performed in three different ways: in liquid phase using triethylamine as the catalyst (1), on the surface of Al2O3/KF solid catalyst (2), or by a MW-assisted Na2CO3-catalyzed procedure (3). In most of the cases, our methods were more efficient and more robust than those applied in the literature. Two of the α-hydroxy-alkylphosphonates were subjected to single-crystal X-ray analysis, suggesting a dimeric and a chain supramolecular buildup in their respective crystals. Four α-hydroxy-alkylphosphonates and one α-hydroxy-ethylphosphine oxide were reacted with different acid chlorides to afford ten α-acyloxyphosphonates. Diethyl α-hydroxy-ethylphosphonate was transformed to the methanesulfonyloxy derivative that was useful in the Michaelis-Arbuzov reaction with triethyl phosphite and ethyl diphenylphosphinite to afford tetraethyl ethylidenebisphosphonate and diethyl α-(diphenylphosphinoyl)-ethylphosphonate, respectively. The α-hydroxyphosphonates and α-hydroxyphosphine oxides prepared were subjected to bioactivity studies, and the compounds tested exhibited limited cytotoxic effects on U266 cells with modest reductions in viability at a concentration of 100 μM.

A Study of Bioactivities and Composition of a Cocktail of Supernatants Derived from Lactic Acid Bacteria for Potential Food Applications.

Growing interests in replacing conventional preservatives and antibiotics in food and pharmaceutical industries have driven the exploration of bacterial metabolites, especially those from strains with generally recognized as safe (GRAS) status, such as lactic acid bacteria (LAB). In this study, a supernatant cocktail derived from multiple LAB strains was prepared and its bioactivities-antimicrobial, antibiofilm, antioxidant, cytotoxicity, and stability-were thoroughly investigated. The cocktail's main components were identified using thermal and protease treatments, gas chromatography coupled to mass spectrometry (GC-MS), and flame ionization detection (GC-FID). The results demonstrated that the supernatant cocktail had a broad inhibition spectrum and was effective against food-related bacterial indicators with the highest activity observed on Bacillus cereus ATCC9634 (inhibition zone sizes 12.33mm) and the lowest on Enterococcus faecium DSM 13590 (3.31mm). It showed dose- and time-dependent delaying effects on the growth of tested fungi. Regarding the antibiofilm activity, it was more effective in preventing biofilm formation (40% biofilm mass reduction) than in degrading preformed biofilm (20% reduction). Additionally, the cocktail showed antioxidant capacity of 10.1 ± 0.3g Trolox equivalent (TE)/kg and dose-dependent cytotoxicity on HEK-293 and HT-29 cell lines. The main bioactive compounds in this cocktail are organic acids (particularly acetic acid), volatiles, and bacteriocin-like compounds. The antimicrobial capacity of this supernatant cocktail was highly reproducible across different fermentation batches, and it remained highly stable at 4°C. Overall, these findings provided novel insights into the functional potentials of LAB metabolites, broadening their application as customizable biopreservatives for food and pharmaceutical industry.

Design, Synthesis, and Biological Activity Evaluation of 5-Aryl-cyclopenta[c]pyridine Derivatives.

Taking the natural product cerbinal as the lead compound, 30 novel 5-aryl-cyclopenta[c]pyridine derivatives were designed and synthesized based on the previous bioactivity studies of the cyclopenta[c]pyridines. The modification of the position-5 of compound 2 was achieved by amination, bromination, and cross coupling using cerbinal as the raw material. The results of the bioactivity tests demonstrated that partial compounds exhibited superior activity against plant viruses compared to compound 2. Compounds 4g and 4k showed higher anti-TMV activity levels than commercial varieties of ribavirin at concentrations of 500 and 100 μg/mL. In particular, compound 4k, which contained a m-methoxyphenyl substitution, displayed the most potent anti-TMV activity in vivo (inactivation effect 51.1 ± 1.9%, curative effect 50.7 ± 3.6%, protection effect 53.8 ± 2.8% at 500 μg/mL) The toxicological experiments also revealed that compound 4k exhibited low toxicity to zebrafish. Additionally, molecular docking results indicated that access to the benzene ring enhanced the binding affinity of these derivatives for TMV receptor proteins. Furthermore, studies on the insecticidal and fungicidal activities of these derivatives showed that most of the compounds exhibited good larvicidal efficacy against Plutella xylostella and broad-spectrum fungicidal activities. Notably, compound 4i (3,4,5-trifluorophenyl) displayed an outstanding inhibition ratio of 91.9% against Sclerotinia sclerotiorum, 75% against Botrytis cinerea, and 62.5% against Phytophthora infestans at a concentration of 50 μg/mL. These results suggest that 5-aryl-cyclopenta[c]pyridine derivatives could serve as promising candidate agents for antiviral, insecticidal, and fungicidal applications in agricultural production.

Template assisted fabrication of nanoporous titanium dioxide coating on 316 L stainless steel for orthopaedic applications

BackgroundSurface modified metallic implants with nanoporous morphology finds extensive application as functional implant material as it mimics the biological conditions as well as matches the mechanical characteristics of the bone. The current study involves synthesis of nano-titania coating by the employment of PMMA as a templating agent and compared with widely used PEG 400. MethodThe titania coatings were synthesized by sol-gel methodology and deposited on 316 L SS by dip coating method. The coating morphology was characterized by Attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-IR), X-ray diffraction analysis (XRD), Scanning electron microscopy - energy dispersive X-ray analysis (SEM-EDX) and Atomic force microscopy (AFM). The bioactive nature of the coatings were evaluated by in vitro bioactivity study in simulated body fluid (SBF). The toxicity and cell adhesion of the coatings were analyzed by MTT assay. The ability of the coatings to resist corrosion was studied with potentiodynamic polarization and electrochemical impedance spectroscopy. Significant findingsThe changes in the cell adhesion behavior are observed for the different coatings. The TiO2 coatings exhibited excellent corrosion resistance. Besides, the nanoporous coating developed with PMMA as the templating agent revealed excellent bioactivity as well as higher corrosion resistance.

Production kinetics and bioactivity study of Aspulvinone pigment from Aspergillus terreus STCP01 for natural colourant applications

Production kinetics and bioactivity study of Aspulvinone pigment from Aspergillus terreus STCP01 for natural colourant applications

Phytochemical and Bioactivity Evaluation of Bee Pollen and Androecia of Castanea, Salix, and Quercus Species.

Qualitative and quantitative differences in the chemical composition between bee pollen originated from Castanea sativa (Türkiye and Slovenia), Salix spp. (Türkiye and Slovenia), and Quercus spp. (Türkiye) and androecia of Castanea sativa, Salix alba, and Quercus pubescens (apetalous trees) were evaluated for the first time by new high-performance thin-layer chromatography (HPTLC) and ultra-performance liquid chromatography (UPLC) methods using marker compounds. N1,N5,N10-tricaffeoylspermidine was isolated, and its structure was elucidated by nuclear magnetic resonance (NMR) and high-resolution mass spectrometry (HRMS). It was the main and the marker compound common to bee pollen (≈3-41 mg/g) and androecia (≈3-6 mg/g) samples. To the best of our knowledge, this is the first report of the identification of N1,N5,N10-tricaffeoylspermidine in bee pollen originated from Salix spp. and androecia of C. sativa, S. alba, and Q. pubescens. The botanical origins of bee pollen were determined via phytochemical profiling using HPTLC-image analyses showing that bee pollen from the same botanical source had almost identical profiles regardless of collection location, geographical differences, and the bee race. In vitro tests and HPTLC-effect-directed analyses (EDAs) were performed to assess antioxidant and xanthine oxidase (XO) inhibitory activities of bee pollen, androecia, and N1,N5,N10-tricaffeoylspermidine. HPTLC-EDA combined with image analyses was used for comparing the activities of bee pollen, androecia, N1,N5,N10-tricaffeoylspermidine, and also other marker compounds (quercetin, myricitrin, hyperoside, quercitrin, isoquercitrin, and rutin). The remarkable bioactivity of N1,N5,N10-tricaffeoylspermidine was for the first time evaluated by HPTLC-EDA and in vitro tests. This is the first study performing HPTLC-XO inhibitory activity analyses on the HPTLC NH2 F254S plates. Further bioactivity studies on botanically and chemically well-characterized bee pollen samples are needed to aid in the use of bee pollen-containing supplements in the prevention and treatment of diseases.

Bioaccessibility and Functional Food Potential of Equisetum telmateia Ehrh. Against Diabetes-Induced Kidney Disorders.

Various species from the genus Equisetum are recorded as food and folk medicine against both kidney complications and diabetes. Equisetum telmateia Ehrh. is documented as a folk remedy in Türkiye against several kidney disorders. This study was designed to evaluate the possible protective mechanisms of E. telmateia EtOH extract (ETE) against kidney disorders and diabetes through different routes, such as the prevention of ROS formation, inhibitory potential against various DM-related enzymes, and a reduction in the amount of the mediators leading to disorders in both systems at the cellular level. The objective was to achieve advanced precision for in vitro results while considering the effect of GIS on oral consumption. Both phytochemical and bioactivity studies were conducted before and after simulated digestion. The results showed that ETE is a rich source of flavonoids and phenolic acids. In addition, it has significant antioxidant and enzyme inhibitory potential. Treatment also yielded promising results at the cellular level for both antioxidative and inhibitor proteins, which may play a role in the pathogenesis of kidney disorders and diabetes. Following the in vitro digestion procedure, both the number of phytochemical ingredients and bioactivity parameters showed a considerable decreasing trend; however, the results are still significant enough to justify the traditional utilization of the genus Equisetum. This investigation demonstrated that ETE has noteworthy potential as a functional food for protection against diabetic kidney disease.

Green Synthesis of Quercetin-Coated Ecofriendly Zirconium Oxide Nanoparticles and Evaluating its in vitro Biological Activities

The development of nanomaterials using green synthesis methods is gaining attention due to their potential to reduce environmental pollution and health risks associated with traditional chemical synthesis methods. Among the various transition metals, zirconia has gained significant interest as filling materials and implants in dentistry due to its excellent mechanical and chemical properties. In this study, we developed ecofriendly zirconium oxide nanoparticles using Biancaea sappan extract as a capping agent and then functionalized them with Quercetin. Further, their anti-inflammatory property and hemocompatibility were evaluated to target their application as filling materials. The biogenic zirconium oxide nanoparticles (B-ZrO2NPs) and quercetin functionalized biogenic zirconium oxide nanoparticles (BQZN) were characterized by UV–Vis Spectroscopy (UV–Vis), Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy X-ray analysis (EDX). B-ZrO2NPs showed maximum absorbance at 267[Formula: see text]nm and 383[Formula: see text]nm. FTIR showed characteristic stretching at 3381[Formula: see text]cm[Formula: see text], confirming the O–H group in the extract and Quercetin used for BQZN formation. The FTIR spectra of BQZN displayed the presence of the characteristic peaks observed in the spectra of B-ZrO2NPs and Quercetin. The broad XRD pattern confirmed the amorphous nature of the zirconia. SEM revealed the spherical morphology of B-ZrO2NPs and BQZN with a size range of around 90[Formula: see text]nm and 120[Formula: see text]nm, respectively. EDAX of BQZN revealed the presence of 45.7[Formula: see text]wt.% Zr, 32.9% oxygen and 21.4% of carbon. In vitro bioactivity studies revealed that BQZN exhibited significant anti-inflammatory activity, as evidenced by the inhibition of protein denaturation. The nanoparticles were also demonstrated for their hemocompatibility with erythrocytes. These findings highlight the potential of BQZN as a promising hemocompatible dental filling with significant anti-inflammatory properties. Further in-depth in vivo studies are required to fully understand their efficacy and toxicity.

The isolation, bioactivity, and synthesis of natural products from Litsea verticillate with anti-HIV activities

Natural products isolated from Litsea verticillata have attracted considerable attention from the chemical community due to their unique structures and promising anti-HIV activities. Recent progresses in the isolation and bioactivity studies for these natural molecules were summarized comprehensively. From the 23 previously uncharacterized compounds isolated from the plant Litsea verticillata, litseaverticillol B demonstrated the most potent anti-HIV activity in vitro, with IC50 ranging from 2 to 3 μg/mL. Meanwhile, litseaverticillol E displayed the highest selectivity index (SI = 3.1), indicating a favorable balance between antiviral potency and cellular toxicity. The plausible biosynthetic pathways and the total synthetic approaches for the representative members (litseaverticillols) were introduced in detail.

Integrated untargeted metabolomics and bioactivity studies as new insights into the chemotaxonomy of Hura crepitans specimens from Peru and Sub-Saharan Africa

Hura crepitans (Euphorbiaceae), is widespread in the Amazon rainforest and on plantations in sub-Saharan Africa. This tree produces an irritating milky latex rich in secondary metabolites, notably daphnane-type diterpenes and cerebrosides. Previous studies have shown that huratoxin, the main daphnane in the latex, significantly and selectively inhibited the growth of colorectal cancer cells through a unique mechanism involving the activation of PKCζ. One major challenge in isolating active molecules from natural products is the accessibility of the resource. This study explores the phytochemical composition and cytotoxic activities of latexes collected in Peru, Benin, and Togo using UHPLC-MS and metabolomics tools to identify a renewable source of bioactive compounds. Significant inter- and intra-continental differences in chemical composition have been highlighted, with daphnanes being concentrated in the Peruvian samples. Extracts form latexes collected in Peru showed cytostatic activity on Caco-2 cells, correlated with the presence of daphnanes, while some African samples exhibited cytotoxic activity on Jurkat and Hela cancer cell lines, leading to the identification of potential other new bioactive compounds such as elasterol and cerebrosides. ObjectiveTo compare the composition of different Hura crepitans latex samples and determine their cytotoxic activity in order to identify new bioactive compounds ConclusionsInter-andintra-continentalvariationsinthephytochemicalcompositionoflatexwereobserved,leadingtosignificantcytotoxicactivitiesondifferentcelllines.DaphnaneswereidentifiedasresponsiblefortheactivityonCaco-2cells,whileelasterolandcerebrosideswereputativelyassociatedwiththeactivityonHelacells.

Research Progress on Activity and Biosynthesis of Diketopiperazines

Abstract: Diketopiperazines (DKPs) are mainly produced by microorganisms. In recent years, active natural products with DKPs structure have been isolated from marine bacteria, actinomycetes and fungi. The stable six-membered ring framework makes DKPs a vital pharmacophore in medicinal chemistry. Several recent studies have demonstrated that it has antibacterial, antifungal, antiviral, antitumor, immunosuppressive, neuroprotective, anti-malaria, anti-prion, and anti-hyperglycemia properties. Some DKPs are signaling molecules for intercellular communication, which can activate or inhibit bacterial Lux R-mediated quorum sensing. They are considered potential new anti-infective drugs that could control biofilm formation by interfering with information communication between microbes. DKPs possess excellent biological activities and have received extensive attention from medicinal chemistry workers. Bioactivity studies of DKPs have revealed that many highly active lead compounds exist in antibacterial, antitumor, and antiviral fields and in treating neurological disorders. This paper reviews the research progress of diketopiperazines in the past ten years.

Structure Revision of Halisphingosine A via Total Synthesis and Bioactivity Studies.

Sphingoid bases are important bioactive lipids found in a variety of organisms, serving as the backbone of sphingolipids, which regulate essential physiological processes. Here we describe the total synthesis and structure revision of halisphingosine A, a sphingoid base initially isolated from marine sponges. To address inconsistencies in the NMR interpretation of this natural product, we developed a synthetic route involving a late-stage enantioselective Henry reaction that allows access to multiple stereoisomers of the proposed halisphingosine A core structure. Our library of 32 fully characterized synthetic stereoisomers enabled us to rectify the structure of halisphingosine A as (2R,3R,8R,Z)-2-aminooctadec-9-ene-1,3,8-triol, and to pursue further structure-activity relation (SAR) studies regarding their antimicrobial and cytotoxic potential. In summary, our study offers a yet unreported compound library along with validated analytical datasets of marine sphingoid base derivatives, which significantly affects future ecometabolomic marine research and will facilitate the identification of inhibitors of sphingolipid metabolism or antagonists of sphingolipid base-sensing receptors.

Role of surface grain refinement in AZ31 Mg alloy by shot peening on surface energy, biomineralization and degradation behavior

Grain refinement of magnesium (Mg) alloys to improve their performance as potential candidates for degradable implant applications is a promising strategy in the field of materials engineering. Surface properties play an important role in promoting higher implant tissue interactions which dictate the healing rate of the fractured bone. In the present work, AZ31 Mg alloy was subjected to shot peening by using steel balls of 2 mm diameter. From the microstructural studies carried out at the cross section, fine grain structure was observed up to 50 μm depth from the surface. Grain refinement up to ∼1.5 μm was achieved at the surface of shot peened AZ31. X-ray diffraction analysis confirms the development of non-basal texture at the surface. Increased surface energy was measured by contact angle measurements for the shot peened AZ31. Higher hardness was measured from the surface in the thickness direction of the AZ31 after shot peening. Corrosion behavior assessed by potentiodynamic polarization tests indicated marginally increased corrosion resistance for shot peened AZ31. In vitro bioactivity studies carried out in simulated body fluids demonstrated higher mineral depositions and lower weight loss for the surface grain refined AZ31. The results demonstrate the potential of shot peening to promote higher biomineralization and to control the degradation in improving the performance of biodegradable AZ31 Mg alloy.

A novel multicomponent micro-alloyed magnesium for orthopaedic applications: a microstructural, mechanical, degradation and bioactivity study

ABSTRACT The current study focuses on development of magnesium based micro-alloy with the composition of Mg–0.5Zn–0.15Ca–0.1Mn–0.1Sn–0.1Ag–0.2Ce–0.2Sr using casting method. Microstructural examinations conducted using optical microscopy and scanning electron microscopy (SEM) unveiled a uniform grain distribution in the alloy with minimal intermetallic content, corroborated by X-ray diffraction (XRD) analysis matching the magnesium peak precisely. Tensile testing indicated that the solution strengthening process boosted the alloy’s required yield strength and stiffness, while enhancing magnesium’s ductility up to 19.07% elongation. Electrochemical tests demonstrated an outstanding corrosion resistance rate of 0.91 mm/year, supported by Nyquist plots indicating passivation behaviour and film formation. The pH variations revealed an initial spike to 8.13 within the first 24 hours, gradually declining thereafter. The bioactivity assessment of the developed alloy showcased the formation of near-stoichiometric apatite layers on the alloy surface, confirming its potential as a suitable orthopaedic implant material.

Cu(II) complexes based on benzimidazole ligands: synthesis, characterization, DFT, molecular docking & bioactivity study.

Aim: The biggest cause of cancer deaths globally was lung cancer. New cancer fighting drugs are needed due to the rising number of cancer patients and cancer cells' treatment resistance.Results: Two Cu(II) complexes, synthesized from ligands based on 2-aminomethyl benzimidazole and salicylaldehyde derivatives, were designed and evaluated for their effectiveness against A549 lung cancer. The compounds were subjected to computational calculation using Density Functional Theory (DFT) to gather information on their reactivity. Furthermore, molecular docking are utilized to simulate the interaction between the compound and the MPP-9 protein. The synthesis of the ligands and their Cu(II) metal complexes are efficient and straightforward. The complexation between copper atom and the ligand are in 1:1 ratio. The MTT assay of the compounds against A549 lung carcinoma reveals that the both Cu(II) complexes good cytotoxicity activity, in comparison to their respective ligands. The low HOMO-LUMO band gap based on the DFT calculation predicts the high reactivity of the compounds. Furthermore, the low binding energy and the numbers of interactions of the Cu(II) complexes with MMP-9 protein binding site coincide with the antiproliferative activity tested in vitro.Conclusion: The cytotoxicity studies performed for Cu(L1Br) are promising, indicating a good candidate for a future drug.

Process optimization and finite element modeling in magnetorheological abrasive finishing of SS-316L with surface characterization

This study explores the potential of Magnetorheological Abrasive Finishing (MRAF) for ultra-precision finishing of SS-316L using a high-performance Nd-Fe-B (N-35 grade) magnetic tool. Key parameters, including the relationship between normal force (Fn) and working gap, magnetic flux distribution, and finishing spot area, were analyzed using ANSYS 2020 R1® Magnetostatic module simulations. Material removal rate (MRR) and surface roughness (Ra) were optimized through response surface methodology (RSM) using a central composite design (CCD) with two primary input factors: SiC abrasive volume fraction (5%, 10%, 15%) and abrasive mesh size (800, 1000, 1200). Statistical analysis via ANOVA revealed a significant influence of process variables, achieving a remarkable surface finish with a minimum Ra of 52 nm in just 60 min, utilizing an MR fluid with 10% SiC abrasives. Microscopic and spectroscopic evaluations confirmed enhanced surface morphology and microstructural refinement. Moreover, bioactivity studies in simulated body fluid highlighted improved hydroxyapatite layer formation on the finished SS-316L samples, underscoring the process’s potential for biomedical applications.