Search Results (74)

Artemisia campestris is a medicinal plant species endemic to Algeria, particularly abundant in the southern regions and the central Sahara. Its long-standing use in traditional medicine has recently gained scientific attention, prompting further investigation into its bioactive potential. This study focuses on the phytochemical composition and biological activity of its hydromethanolic extract, with a particular emphasis on its ability to inhibit neural enzymes associated with insect physiology with particular relevance to Aphis gossypii (Glover), a major polyphagous agricultural pest. Preliminary screening revealed a diverse array of secondary metabolites, including tannins (catechic and gallic), flavonoids, quinones, glycosides, terpenoids, saponins, coumarins, and alkaloids; however, anthocyanins were not detected. Quantitative analysis confirmed high concentrations of total phenolics (80.91 ± 1.58 mg GAE/g), flavonoids (60.45 ± 2.02 mg RE/g), phenolic acids (4.24 ± 0.38 mg CAE/g), and condensed tannins (2.26 ± 0.29 mg CE/g). Enzyme inhibition assays were performed using Ellman’s method, and IC₅₀ values were calculated by nonlinear regression analysis based on dose–response curves. The extract demonstrated significant in vitro inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), with IC₅₀ values of 13.79 ± 0.79 µg/mL and 8.34 ± 0.58 µg/mL, respectively. Molecular docking analyses further confirmed strong binding affinities of cyanidin-3-O-glucoside, malvidin-3-O-glucoside, and apigenin (−8.20 to −8.50 kcal/mol) with the AChE active site, stabilized by hydrogen bonding and π–π interactions with key residues. These results were benchmarked against galantamine, a reference inhibitor, which exhibited IC₅₀ values of 1.50 ± 0.12 µg/mL under the same conditions. Although galantamine showed superior potency, the relatively low IC₅₀ values of the A. campestris extract support its potential as a natural cholinesterase-inhibitory agent warranting further investigation. These findings suggest that A. campestris may represent a promising source of natural cholinesterase inhibitors with potential relevance for eco-friendly insect control. These in vitro and in silico findings provide a mechanistic rationale warranting future in vivo bioassay validation against A. gossypii and related agricultural pests. Full article

Acetylcholinesterase (AChE) inhibition remains a key therapeutic strategy in the management of neurodegenerative disorders such as Alzheimer’s disease. In this study, the inhibitory potential of the gastric pentadecapeptide BPC-157 and two newly designed hybrid analogs, CIARA-1 and CIARA-2, was investigated for the first time. The hybrid peptides were rationally designed by combining a BPC-157-derived fragment with an arginine-containing C-terminal sequence to enhance interactions with the enzyme’s active and peripheral binding sites. Enzyme kinetics were evaluated using a modified Ellman assay, and inhibition parameters were determined through Lineweaver–Burk analysis. All tested compounds exhibited a competitive mechanism of inhibition, as evidenced by increased Michaelis–Menten constant (K_m) values with unchanged maximum velocity (V_max), indicating competition with the substrate at the catalytic site of AChE. Among the tested compounds, CIARA-1 demonstrated the highest inhibitory potency, reflected by the lowest inhibition constant (K_i = 0.24 mM) and IC₅₀ value (2.52 mM), followed by CIARA-2 (K_i = 0.29 mM; IC₅₀ = 2.73 mM) and BPC-157 (K_i = 0.48 mM; IC₅₀ = 2.80 mM). These findings were consistent with molecular modeling predictions, supporting stronger binding interactions for CIARA-1. Despite significantly lower potency compared to clinically used AChE inhibitors, the studied peptides represent a promising scaffold for further optimization. Overall, this work demonstrates that BPC-157 and its hybrid analogs act as reversible competitive AChE inhibitors, with enhanced activity observed for structurally modified derivatives. The results highlight the potential of peptide-based hybrid molecules as multifunctional candidates in the development of novel therapeutics targeting cholinergic dysfunction. Full article

Ambrosia arborescens Mill., a native medicinal plant traditionally used in the Andean region, has a poorly characterized essential oil (EO), with no prior reports on its anticholinesterase or antioxidant potential. As a first report and preliminary screening study, this work characterizes the chemical composition of the EO and evaluates its acetylcholinesterase (AChE) inhibitory and antioxidant activities. The EO was isolated by hydrodistillation and analyzed using gas chromatography coupled with mass spectrometry (GC–MS) and flame ionization detection (GC-FID). The biological activities were evaluated using the Ellman method to determine AChE inhibition and using ABTS and DPPH assays to determine antioxidant activity. Analysis of the chemical composition revealed 31 compounds, and the major components were γ-curcumene (28.63%), trans-muurola-4(14),5-diene (27.85%), and eucavone (18.46%). The EO showed moderate AChE inhibitory activity, with an IC₅₀ value of 28.04 ± 1.02 µg/mL, and limited antioxidant activity, with ABTS SC₅₀ = 373.75 ± 1.30 µg/mL and DPPH SC₅₀ = 1101.84 ± 1.63 µg/mL. These findings demonstrate that the EO possesses selective anticholinesterase activity and limited antioxidant capacity. Given the structural diversity of its constituents, the observed bioactivity is likely the result of the combined contributions of multiple components; however, the specific active constituents and potential synergistic interactions require further investigation through bioassay-guided fractionation. These findings represent the first preliminary screening of the biological activities of A. arborescens EO and provide a foundation for future bioactivity-guided investigations. Full article

Cysteine-modified succinoglycan (SG-Cys) was synthesized via EDC/NHS-mediated amidation by grafting cysteine onto succinoglycan isolated from Sinorhizobium meliloti. The successful introduction of cysteine moieties was confirmed by 1H NMR and FTIR analyses, while the degree of substitution was quantitatively determined using Ellman’s assay. The incorporation of cysteine significantly influenced the physicochemical and rheological properties of the polymer. In particular, SG-Cys exhibited up to a 1.8-fold increase in viscosity compared with native succinoglycan. The viscoelastic behavior of SG-Cys was systematically evaluated under various environmental conditions, including different pH, ionic strengths, temperatures, and polymer concentrations, revealing enhanced responsiveness to external stimuli. Radical scavenging assays demonstrated that SG-Cys displayed up to a 2.5-fold increase in antioxidant capacity compared with unmodified SG, as determined by DPPH and ABTS assays. Cytotoxicity evaluation using HEK-293 cells confirmed that the modified polymer exhibited no significant cytotoxic effects. Overall, the results demonstrate that thiol functionalization of succinoglycan effectively improves both rheological performance and antioxidant activity, suggesting that SG-Cys is a promising multifunctional bioactive polymer for potential applications in biomaterials, drug delivery, and bioengineering systems. Full article

This study addresses the challenge of accurately assessing diazinon exposure in suspected self-poisoning cases. We evaluated butyrylcholinesterase (BChE) levels using a point-of-care (POCT) whole blood assay (adapted Ellman method) and compared it with the standard plasma Enzyme Multiplied Immunoassay Technique (EMIT). Diazinon exposure in four patients was confirmed using a validated gas chromatography–tandem mass spectrometry (GC-MS/MS) method with multiple reaction monitoring (MRM). A strong positive correlation was observed between POCT and EMIT BChE activity (r = 0.9638, p < 0.0001), indicating general agreement in BChE trends. However, Bland–Altman analysis revealed discrepancies in absolute BChE values. Notably, admission diazinon concentrations (GC-MS/MS) were significantly negatively correlated with BChE activity measured by both POCT (r = −0.9333, p = 0.0205) and EMIT (r = −0.9302, p = 0.0219). The POCT assay offers rapid, preliminary BChE assessments in suspected diazinon intoxication, useful in emergency settings. However, due to observed discrepancies, confirmatory testing with EMIT or GC-MS/MS is recommended for accurate quantification. This research highlights the critical need for robust confirmatory methods, such as GC-MS/MS, to validate rapid assays and improve the accuracy of diazinon intoxication detection. Full article

Early detection of cancer can dramatically improve long-term prognosis and survivability in a variety of different cancer types. However, for many cancer types, the ability to effectively detect early-developing tumors is challenging, especially in physiological locations with limited visibility or access. Previously, we reported a sensing platform and methodology to detect biomarker peptides found in urine from ovarian cancer patients. This sensing platform relies on peptide interactions with gold nanoclusters through thiol-mediated linkages; thus, the sensitivity of the biomarker assay is directly related to appropriate redox states of the biomarkers in question. Here, we report on an expansion of the traditional thiol-reactivity assay originally developed by Ellman to include and evaluate a variety of solution modifications that may be used in conjunction with the biomarker-sensing platform. Because biomarker peptides may be isolated from a variety of biological tissues or fluids, depending on the target condition or disease, we screened numerous solution conditions that may be directly used in sample preparation and peptide extraction. The data demonstrate that the assay maintains linearity under these various conditions. The assay was then applied to a variety of models and biomarker peptides and exhibits the expected linear response. These results demonstrate the applicability of the thiol-reactivity assay to biologically derived samples, and the flexibility to ensure sample preparation and treatment will retain the appropriate sample redox conditions to ensure optimal interactions with the biosensor platform. It also facilitates the ability to perform quality control on clinically derived biological samples to ensure appropriate preparations, and concentrations are available for application to the nanopore biosensor platform. Full article

Background: The cholinergic hypothesis is an elementary approach employed for the research and drug discovery of novel anti-Alzheimer therapeutics. Method: In this context, the study focuses on synthesizing and evaluating a new series of chalcone derivatives (3a–3j) as multifunctional therapeutic agents, specifically investigating their antioxidant potential using the DPPH method with ascorbic acid as a standard. Ellman’s protocol for acetylcholinesterase inhibition assay was performed using donepezil as a standard, and computational insights were explored through molecular docking and ADME profiling. Results: Compounds 3a, 3d, 3e, 3f, and 3h exhibited excellent antioxidant activity compared to the standard. Most of the compounds exhibited moderate to good (3b, 3c, and 3h) AChE inhibitory activity. Molecular docking studies revealed conventional hydrogen bonding and π-π interactions with the enzyme’s active residues, facilitated by their electronegative groups and phenyl rings, respectively. In addition, a pharmacokinetic study was conducted using computational approach to assess druggability. The results demonstrated that compound 3b is an outstanding lead candidate with appreciable AChE inhibitory activity. Conclusions: The combined experimental and computational results of this study highlight the multifunctional nature of chalcone derivatives, suggesting their potential as promising therapeutic agents for the discovery of novel AChE inhibitors that could be employed in the management of Alzheimer’s disease and oxidative stress-related diseases. Full article

Conventional hair-straightening methods that use chemical treatments to break disulfide bonds cause severe damage to the hair shaft, leading to weakened hair that is prone to reverting to its curly form in high humidity. Therefore, a unique haircare coating technology is required to protect hair integrity and provide a long-lasting straightening effect. Herein, we designed a hair-straightening technology by integrating a nature-inspired polyphenol–inorganic sulfate (PIS) redox agent into formulated shampoo, which achieves a desirable straightening effect through sulfate-induced disulfide breakage while preserving hair integrity through a polyphenol-reinforced structure. The interaction between polyphenols and residual thiols from the straightening process maintained a long-lasting straight hair structure and hair strength. Ellman’s assay showed a lower free thiol content from reductant-induced damaged keratin in PIS shampoo-treated hair than in sulfate-treated hair as the polyphenol–thiol bond was formed through the Michael addition reaction, thereby restoring the natural structure of the hair and enhancing its mechanical properties. Owing to the polyphenol coating, PIS shampoo-treated hair exhibited an antistatic effect and high hydrophobicity, indicating healthy hair. Furthermore, the polyphenol coating effectively scavenged radical oxygen species (ROS) in the hair, thereby improving damage protection. Thus, PIS shampoo offers an alternative approach for effective hair straightening. Full article

Alzheimer’s disease (AD) is a neurodegenerative condition characterized by a gradual decline in cognitive function, for which few effective treatments exist. This study investigated the neuroprotective potential of Oroxylum indicum root extract and its key constituents (baicalein, chrysin, oroxylin A) against AD hallmarks. The extract and its constituents exhibited antioxidant activity in the DPPH assay. They inhibited β-amyloid aggregation as measured by the thioflavin T assay and acetylcholinesterase activity using the Ellman method. In cell culture models, O. indicum extract showed an ability to protect neurons from the toxic effects of H₂O₂. Western blot analysis revealed the extract and its major active component, baicalein, downregulated pro-apoptotic markers (cleaved caspase-3, and BAX) upon H₂O₂ exposure. Furthermore, they reduced the expression of amyloidogenic proteins (BACE1) and phosphorylated tau. These findings suggest that O. indicum root extract, particularly baicalein, possesses multifaceted neuroprotective properties, targeting various aspects of AD pathogenesis, including oxidative stress, cholinergic dysfunction, β-amyloid formation, aggregation, and apoptosis. O. indicum root thus warrants further investigation as a promising source of therapeutic agents for AD. Full article

Alzheimer’s disease (AD) poses a significant public health issue. Despite the fact that today there are several methods of maintenance therapy, one of the most widely used methods is designed to correct the deficiency of acetylcholine. In the search for new potential inhibitors of cholinesterase enzymes, eight new derivatives of 3-oxo- or 2,3-indolo-triterpenic acid conjugated with amino-quinuclidine bicyclic cores were designed and synthesized. Then, the obtained compounds were screened in Ellman’s assays for their ability to inhibit acetylcholinesterase enzyme, and for each of the active compounds, the type of inhibition was determined. The obtained results demonstrate the dependence of the activity on the triterpenoid structure and the type of substituents. The best activity for ursolic acid derivatives was observed for the 3-oxoamide 8, with an IC₅₀ value of 0.43 µM, acting as a mixed-type inhibitor. In turn, for the oleanane type, the amide with an indole unit in the A ring 11 exhibited the best activity with an IC₅₀ value of 0.47 µM (while the ursane-type analog was weakly active) and led to an uncompetitive type of inhibition. Thus, 3-amidoquinuclidine-triterpenoids conjugates could be considered novel inhibitors of acetylcholinesterase with a different mechanism of action. Full article

Alzheimer’s disease (AD), a multifactorial neurodegenerative disorder characterized by severe cognitive impairment, affects millions of people worldwide. However, AD therapy remains limited and mainly symptomatic-focused, with acetylcholinesterase (AChE) inhibitors being the major available drugs. Thus, AD is considered by the WHO as a disorder of public health priority. Among several strategies that have been identified to combat AD, the use of natural multi-target drug ligands (MTDLs) appears to be a promising approach. In this context, we previously found that the essential oils (EOs), obtained via hydrodistillation, from Azorean Cryptomeria japonica sawdust (CJS) and resin-rich bark (CJRRB) were able to exert antioxidant activity via different mechanisms of action. Therefore, in the present work, these EOs were screened for their (i) in vitro anti-AChE and anti-butyrylcholinesterase (BChE) activities, evaluated by a modified Ellman’s assay; (ii) in vitro anti-inflammatory potential, using the albumin denaturation method; and (iii) toxicity against Artemia salina. The CJRRB–EO exhibited both anti-AChE and anti-BChE activities (IC₅₀: 1935 and 600 µg/mL, respectively), whereas the CJS–EO only displayed anti-BChE activity, but it was 3.77-fold higher than that of the CJRRB–EO. Molecular docking suggested that α-pinene and ferruginol compounds contributed to the anti-AChE and anti-BChE activities, respectively. Moreover, the anti-inflammatory activity of the CJS–EO, the CJRRB–EO, and diclofenac was 51%, 70%, and 59% (at a concentration of only 2.21 μg/mL), respectively, with the latter two presenting comparable activity. Concerning the EOs’ potential toxicity, the CJRRB–EO exhibited a lower effect than the CJS–EO (LC₅₀: 313 and 73 µg/mL, respectively). Overall, the EOs from C. japonica biomass residues, chiefly the CJRRB–EO, displayed antioxidant, anticholinesterase, and anti-inflammatory activities in a concentration-dependent manner. These properties demonstrate that these residues may be suitable natural MTDLs for AD complementary therapy when administered through aromatherapy, or, alternatively, could serve as low-cost sources of valuable ingredients, such as α-pinene. Full article

Anticancer drugs cause anemia in patients through eryptosis and hemolysis. We thus studied the in vitro toxicity of galangin (GAL) in red blood cells (RBCs). RBCs were exposed to 50–500 μM of GAL and analyzed for markers of eryptosis and hemolysis. Ca²⁺ nucleation, phosphatidylserine (PS) externalization, oxidative stress, and cell size were detected via fluorescence-activated cell sorting using Fluo4/AM, annexin-V-FITC, 2′,7′-dichlorodihydrofluorescein diacetate, and forward scatter (FSC), respectively. Acetylcholinesterase (AChE) activity was measured via Ellman’s assay and ultrastructural morphology was examined via scanning electron microscopy. Membrane rupture and extracellular hemoglobin, aspartate transaminase (AST), and lactate dehydrogenase (LDH) were assessed via colorimetric methods. Distinct experiments were carried out to identify protective agents and signaling pathways using small-molecule inhibitors. GAL triggered sucrose-sensitive hemolysis with AST and LDH leakage, increased annexin-V-FITC and Fluo4 fluorescence, and decreased FSC and AChE activity which was associated with the formation of granulated echinocytes. Ca²⁺ omission and energy replenishment with glucose, adenine, and guanosine blunted PS externalization and preserved cellular volume. Moreover, caffeine, Trolox, heparin, and uric acid had similar ameliorative effects. Hemolysis was abrogated via caffeine, Trolox, heparin, mannitol, lactate, melatonin, and PEG 8000. Notably, co-treatment of cells with GAL and staurosporin, D4476, or acetylsalicylic acid prevented PS externalization whereas only the presence of SB203580 and NSC23766 rescued the cells from GAL-induced hemolysis. Ca²⁺ nucleation and metabolic collapse mediated by PKC/CK1α/COX/p38/Rac1 drive GAL-induced eryptosis and hemolysis. These novel findings carry ramifications for the clinical prospects of GAL in anticancer therapy. Full article

In this work, for the first time, different parts of the Finger Lime (Citrus australasica F. Muell.), such as pulp, peel and seeds, were analyzed by HS-SPME-GC/MS, and NMR techniques in order to describe its volatile and non-volatile chemical profile. The results highlighted the presence of a high number of terpenes with limonene as principal component in all investigated parts (ranging from 40.4% to 62.6%) and molecules belonging to the classes of amino acids, organic acids, carbohydrates, fatty acids, phenols and miscellaneous compounds that followed a different trend between the investigated different parts. In this study, the inhibition of ChEs (AChE and BChE) was evaluated using the spectrophotometric method of Ellman. The results showed that only peel extract weakly inhibited AChE (14%). Based on these data, this extract was further investigated by GC/MS after derivatization. Furthermore, peel extract was chosen to evaluate the in vitro effects on two human glioblastoma cells lines (U87 and LN18). Flow cytometry results showed that citrus extract was more effective in down-regulating the expression of the adhesion molecule CD44. In fact, after 72 h with 400 µg/mL of citrus extract, CD44 expression levels were reduced in both U87 and LN18 glioblastoma cell lines. This was confirmed by immunofluorescence analysis, which also showed a modification of CD44 antigen localization in both U87 and LN18 cell lines. Moreover, wound assay data supported its ability to reduce glioblastoma cell’s motility. The migration ability of U87 cells decreased (85% control vs. 50% at 400 μg/mL), while it was even more pronounced in resistant LN18 cells (93% control vs. 15% at 400 μg/mL). The findings highlighted that citrus peel extract could have an anti-invasive activity for glioma management. Full article

The therapeutic effectiveness of current neurodegenerative disease treatments is still under debate because of problems with bioavailability and a range of side effects. Fungi, which are increasingly recognized as sources of natural antioxidants and acetylcholinesterase (AChE) enzyme inhibitors, may thus serve as potent neuroprotective agents. Previous studies have associated the anti-AChE and antioxidant activities of fungi mostly with polysaccharides and phenolic compounds, while other secondary metabolites such as polyamines (PAs) have been neglected. This study aimed to investigate eight edible and medicinal fungi from Serbia, marking the initial investigation into the neuroprotective capabilities of Postia caesia, Clitocybe odora, Clitopilus prunulus, and Morchella elata. Neuroprotective activity was examined using the Ellman assay, while the antioxidant capacity was tested by conducting DPPH, NO, ABTS, and FRAP tests. PA levels were determined by high-performance liquid chromatography (HPLC) coupled with fluorescent detection. Ganoderma applanatum and Lepista nuda exhibited the most robust anti-AChE (98.05 ± 0.83% and 99.94 ± 3.10%, respectively) and antioxidant activities, attributed to the synergistic effects of the total protein, total phenolic, and PA levels. Furthermore, P. caesia displayed significant AChE inhibition (88.21 ± 4.76%), primarily linked to the elevated spermidine (SPD) (62.98 ± 3.19 mg/kg d.w.) and putrescine (PUT) levels (55.87 ± 3.16 mg/kg d.w.). Our results highlight the need for thorough research to comprehend the intricate relationships between distinct fungus species and AChE inhibition. However, it is important to recognize that more research is required to identify the precise substances causing the reported inhibitory effects. Full article

Elettaria cardamomum (L.) Maton (Zingiberaceae family) is a plant traditionally used in Ayurvedic and Chinese medicine. In this work, the essential oil of E. cardamomum was found to inhibit the enzymes AChE (62.6% of inhibition, IC₅₀ 24.9 μg/mL) and BChE (55.8% of inhibition, IC₅₀ 25.9 μg/mL) by performing an in vitro colorimetric assay using the Ellman method. A bio-guided fractionation approach was used to isolate fractions/pure compounds that were tested individually to evaluate their activity. The resulting oxygenated fraction was found to be active against both AChE (percentage inhibition 42.8%) and BChE (percentage inhibition 63.7%), while the hydrocarbon fraction was inactive. The activity was attributed to a pool of oxygenated terpenes (α-terpinyl acetate, 1,8-cineole, linalool, linalyl acetate, and α-terpineol) that synergistically contributed to the overall activity of the essential oil. Full article