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This study aimed to evaluate the antioxidant, anticholinesterase, and α-glucosidase (AG) inhibitory activities of the ethanolic leaf extract, characterize its phenolic composition, and investigate the interactions of the major identified phytochemicals with the target enzymes through molecular docking analysis. The phenolic profile was determined by LC–MS/MS, antioxidant activity was assessed using DPPH and ABTS radical scavenging assays, enzyme inhibitory activities against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and AG were evaluated in vitro, and molecular docking was performed to examine ligand–enzyme interactions. Among the analyzed compounds, quercetin, myricetin, fumaric acid, vanillic acid, 4-hydroxybenzoic acid, and salicylic acid were identified as the predominant phenolics in the leaf extract. The extract exhibited DPPH and ABTS radical scavenging activities of approximately 19% and 11%, respectively. It also demonstrated potent enzyme inhibitory activity, with IC₅₀ values of 5.76 ± 0.21 µg/mL for AChE, 3.82 ± 0.17 µg/mL for BChE, and 6.24 ± 0.50 µg/mL for AG. Molecular docking analysis revealed that myricetin and quercetin exhibited the most favorable binding affinities toward AChE, BChE, and AG. Myricetin showed docking scores of −11.188, −9.642, and −7.899 kcal/mol against AChE, BChE, and AG, respectively, supported by hydrogen-bonding, π–π stacking, and hydrophobic interactions within the enzyme active sites. Re-docking validation yielded RMSD values below 2.0 Å for all targets, confirming the reliability of the docking protocol. These findings demonstrate that H. sabdariffa leaf extract is a rich source of bioactive phenolics with promising antioxidant and enzyme inhibitory properties, while molecular docking provides structural evidence supporting the observed biological activities.

Tribulus terrestris (TT) is a medicinal plant traditionally utilized in the management of various health conditions, including inflammation, edema, and hypertension. The present study aimed to investigate the phenolic profile of the ethanolic extract of TT and to evaluate its antioxidant, antimicrobial, anticholinesterase, and α-glucosidase inhibitory properties. Phenolic analysis revealed several quantified compounds, including vanillic acid, resveratrol, fumaric acid, acetohydroxamic acid, quercetin, hydroxybenzoic acid, salicylic acid, butein, caffeic acid, and catechin hydrate, while phloridzin dihydrate was detected below the quantification limit. Among the detected compounds, vanillic acid was found to be the predominant phenolic component. Biological activity assays demonstrated that the extract possessed remarkable cholinesterase inhibitory potential, exhibiting IC₅₀ values of 9.11 ± 2.12 μg mL⁻¹ and 8.77 ± 0.62 μg mL⁻¹ against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), respectively. Furthermore, antioxidant capacity was confirmed through FRAP and CUPRAC assays, with corresponding values of 0.136 and 0.296. The antimicrobial efficacy of the extract was evaluated against Staphylococcus aureus, Escherichia coli, and Salmonella Typhimurium, revealing inhibitory effects against all tested bacterial strains. Overall, the findings indicate that the TT represents a promising natural source of phenolic compounds with significant antioxidant, antibacterial, and enzyme inhibitory activities, supporting its potential application in the development of pharmaceutical and therapeutic products.

This study presents the phytochemical and biological evaluation of the species Hedysarum yilmazunalii Kandemir, F. Yıldız & H.İ. Turkoğlu. Methanolic extracts from leaves, stems, and roots were characterized by LC‐MS/MS, and their antioxidant, enzyme inhibitory, and antiproliferative activities were investigated. The analyses showed organ‐specific differences in phenolic composition, with quinic acid as the major compound in leaves together with higher levels of flavonoid glycosides, including astragalin and isoquercitrin. Aerial extracts showed strong enzyme inhibitory activity. Leaf and stem extracts exhibited cholinesterase inhibition, with IC ₅₀ values of 5.82 and 6.42 µg/mL for AChE and 5.41 and 5.50 µg/mL for BChE, respectively. The leaf extract showed α ‐glucosidase inhibitory activity (4.10 µg/mL), comparable to acarbose, and antioxidant activity (DPPH: 6.46 µg/mL), together with the highest phenolic (145.43 mg GAE/g extract) and flavonoid contents (87.20 mg QE/g extract). Antiproliferative assays demonstrated growth inhibition of lung and breast cancer cell lines, with the lowest GI ₅₀ values of 1.00 µg/mL for H1650 and 2.34 µg/mL for MDA‐MB‐231 cells. LDH cytotoxicity remained low (2.25%–12.59%), indicating limited membrane damage in both cancer and normal cells. These findings identify H. yilmazunalii as a source of compounds with antioxidant, neuroprotective, antidiabetic, and anticancer potential.

This study presents a comprehensive evaluation of the phenolic composition and biological activities of methanolic extracts obtained from the aerial (GLM) and root (GLRM) parts of Glaucium leiocarpum. Phenolic profiling was conducted using reversed-phase high-performance liquid chromatography (RP-HPLC), revealing catechin hydrate, 3-hydroxybenzoic acid, syringic acid, hesperidin, chlorogenic acid, caffeic acid, and trans-cinnamic acid as major constituents in GLM. In contrast, GLRM exhibited a more diverse phenolic profile, including epicatechin, benzoic acid, quercetin, gallic acid, and rosmarinic acid. Antioxidant activities were evaluated using DPPH and FRAP assays, with GLRM demonstrating stronger radical scavenging capacity (IC₅₀: 36.96 µg/mL) and higher ferric reducing power (173.20±0.68 mg TE/g extract). GLRM also contained significantly higher levels of total phenolics (142.81±2.87 mg GAE/g) and flavonoids (76.67±0.72 mg QE/g). Antimicrobial assays demonstrated that only GLRM exerted inhibitory effects against Staphylococcus aureus (8.7±0.57 mm), Enterococcus faecalis (7.7±0.57 mm), and Streptococcus pneumoniae (15.0±0.0 mm). Cytotoxicity studies, assessed by the XTT assay, revealed potent antiproliferative effects against HT-29 colorectal cancer cells (IC₅₀: 3.59 µg/mL for GLM, 2.29 µg/mL for GLRM) and moderate activity against A549 lung carcinoma cells (IC₅₀: 36.01 µg/mL for GLM, 21.99 µg/mL for GLRM). Furthermore, GLRM exhibited strong anticholinesterase activity, with IC₅₀ values of 2.85±0.27 µg/mL for acetylcholinesterase (AChE) and 2.47±0.07 µg/mL for butyrylcholinesterase (BChE). Overall, these findings underscore G. leiocarpum, particularly its root extract, as a valuable source of bioactive secondary metabolites, owing to its rich polyphenolic profile and notable antioxidant, antimicrobial, cytotoxic, and cholinesterase inhibitory activities.

One of the most important strategies in the management of type 2 diabetes is controlling postprandial hyperglycemia, and α-glucosidase inhibitors are commonly used to achieve this. However, the side effects that may arise from the long-term use of synthetic inhibitors have increased interest in naturally derived alternatives. In this study, the α-glucosidase inhibitory activities of ethanol extracts from Thymus sipyleus Boiss., Salvia officinalis L., and Lavandula stoechas L. were evaluated in comparison with acarbose, a reference inhibitor. The results showed that all plant extracts examined exhibited strong inhibitory activity against α-glucosidase. The highest inhibitory activity was found in S. officinalis (IC50: 2.44±0.086 µg/mL); This was followed by T. sipyleus (2.71±0.40 µg/mL) and acarbose (2.85 ± 0.23 µg/mL). L. stoechas also exhibited significant but lower inhibitory activity (5.68 ± 0.05 µg/mL). The higher α-glucosidase inhibitory activity of S. officinalis and T. sipyleus extracts compared with acarbose suggests that these species may represent promising natural sources of α-glucosidase inhibitors. While the α-glucosidase inhibitory activity of S. officinalis has been previously reported, data regarding T. sipyleus and L. stoechas remain limited. This study provides novel comparative data on the α-glucosidase inhibitory activities of these three species and highlights their potential as promising natural sources of α-glucosidase inhibitors for further investigation.

Hedysarum erythroleucum is a plant species native to Türkiye and represents a potential source of bioactive compounds. This study investigated the phytochemical composition and biological activities of methanolic extracts prepared from the leaves, stems, and roots. LC‐MS/MS analysis identified 53 phenolic compounds and revealed clear differences in metabolite distribution among plant organs. Quinic acid was the predominant phenolic acid, particularly in the leaf extract. Flavonoid glycosides such as isoquercitrin, astragalin, and rutin were also abundant in the aerial parts of the plant. The antioxidant potential of the extracts was evaluated using DPPH, FRAP, total phenolic content, and total flavonoid content assays. Among the tested plant parts, the leaf extract exhibited the strongest antioxidant activity, with the lowest DPPH IC ₅₀ value, the highest reducing power, and the highest total phenolic and flavonoid contents. These findings indicate that the leaves contain high levels of antioxidant compounds. Enzyme inhibition assays showed that the leaf extract exhibited the highest inhibitory activity against acetylcholinesterase, butyrylcholinesterase, and α ‐glycosidase. Its activity was comparable to that of the reference inhibitors under the experimental conditions. Antiproliferative activity was assessed against lung and breast cancer cell lines. All extracts inhibited cancer cell growth, with the highest sensitivity observed in H1650 and MDA‐MB‐231 cells. Tumor selectivity indices suggested moderate selectivity, especially for root extracts. LDH cytotoxicity analysis indicated limited membrane damage, suggesting that the extracts primarily exert cytostatic effects by suppressing cell proliferation rather than inducing extensive cell death. Multivariate analyses revealed organ‐specific metabolite patterns and associations between phenolic composition and the measured biological activities. Overall, the findings indicate that H. erythroleucum , particularly the leaf extract, contains a high content of phenolic compounds and exhibits promising in vitro antioxidant, enzyme inhibitory, and antiproliferative activities. These findings provide a basis for future phytochemical investigations, mechanistic studies, compound isolation, and in vivo validation.

Propolis is recognized for its biological activities; however, its chemical composition varies according to environmental conditions, which presents challenges for quality standardization and biological evaluation. Although propolis has been widely investigated, information regarding variation among samples collected from geographically close locations within the same region is limited. Therefore, this study investigated whether propolis samples obtained from different locations within Erzincan Province exhibit differences in chemical composition and biological activities and evaluated the relationship between environmental conditions and propolis characteristics. Eleven propolis samples collected from Erzincan, Türkiye, were analyzed for phenolic composition, antioxidant capacity, antimicrobial activity, acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and α ‐glucosidase inhibitory activities. Twenty‐eight compounds were identified, with gallic acid, protocatechuic acid, chlorogenic acid, hydroxybenzaldehyde, caffeic acid, and vanillin detected as major constituents. AChE inhibitory activity varied between 1.28 and 6.44 µg/mL, while BChE inhibitory activity varied between 1.85 and 9.66 µg/mL. All samples exhibited antibacterial activity. Total phenolic and flavonoid contents were 141.70–255.04 mg GAE/g extract and 30.48–93.81 mg QE/g extract, respectively. The KMH sample showed the antioxidant activity. The results demonstrated variation in phytochemical composition and biological activities among propolis samples collected within the same province, indicating associations between flora, environmental conditions, propolis quality, and bioactivity.

Hedysarum candidissimum (HC), a species endemic to Türkiye, represents a potential source of bioactive phytochemicals with pharmacological applications. This study provides the first comprehensive investigation of the species, integrating organ‐specific phytochemical profiling with biological activity evaluations. Methanolic extracts from leaf, stem, and root were analyzed for their phytochemical composition and biological activities. Liquid Chromatography–Tandem Mass Spectrometry analysis quantified 53 phenolic compounds and revealed organ‐dependent differences in metabolite distribution. Quinic acid was the major phenolic acid, with the highest content in the stem (91.81 mg/g extract), while flavonoid glycosides such as isoquercitrin (90.72 mg/g extract) and astragalin (43.61 mg/g extract) were higher in leaves. Antioxidant activity was determined by DPPH, FRAP, TPC, and TFC assays. The leaf extract showed the strongest activity, with the lowest DPPH IC ₅₀ (5.43 ± 0.18 µg/mL), highest reducing power (192.47 ± 0.91 mg TE/g extract), and highest phenolic and flavonoid contents (220.84 ± 1.07 mg GAE/g extract and 107.26 ± 0.77 mg QE/g extract). Enzyme inhibition assays demonstrated strong activity against acetylcholinesterase, butyrylcholinesterase, and α‐glucosidase (2.44 ± 0.11, 3.35 ± 0.37, and 3.40 ± 0.20 µg/mL). Antiproliferative activity showed moderate growth inhibition in lung (A549, Calu1, H1650) and breast (MCF‐7, MDA‐MB‐231) cancer cell lines (GI ₅₀ : 2.40–19.15 µg/mL), with higher sensitivity in breast cells. The stem extract exhibited the highest tumor selectivity index (1.83), while LDH assays indicated low toxicity. Multivariate analyses confirmed organ‐specific metabolite patterns and relationships between phenolic composition and biological activities. These findings indicate that the species, particularly the leaf extract, represents a source of phenolic metabolites for further phytochemical and biological investigation.

The purpose of this study was to ascertain the phytochemical composition and antiproliferative properties of methanolic extract made from the roots, branches, leaves, and flowers of Echinophora chrysantha (EC). Phytochemical content was determined using RP-HPLC. Sixteen metabolites were identified as a result of RP-HPLC examination of EC extracts. Using the XTT technique, antiproliferative activity tests were examined on HT29 and A549 cell lines. All extracts strongly inhibited the examined cell lines. In particular, the branch extract shown outstanding antiproliferative activity against A549 (IC50:7.40 μg/mL) and HT-29 (IC50:1.70 μg/mL). Echinophora chrysantha's traditional use and therapeutic usefulness are further reinforced by the identification of its metabolites and assessment of its bioactivity.

The aim of this study was to determine the secondary metabolites of the n‐hexane, ethyl acetate, methanol, and water extracts of Achillea sintenisii Hub. Mor. and to ascertain their divergent biological properties. LC–MS/MS analysis was performed to identify the bioactive compounds. The anticancer properties of the samples were tested against human breast (MCF‐7 and MDA‐MB‐453) and colon (HT‐29) cancer cell lines by XTT assay. The anti‐Alzheimer's studies were performed using Ellman's assay. The antimicrobial studies were carried out by Kirby–Bauer disc diffusion method. The antioxidative potential of the samples was evaluated on the basis of 2,2‐diphenyl‐1‐picrylhydrazyl scavenging and ferric reducing antioxidant power assays, LC–MS/MS analysis revealed 27 phytochemicals, including high concentrations of quinic acid, gentisic acid, chlorogenic acid, luteolin, cynaroside, and caffeic acid. Ethyl acetate extract exhibited the most potent cytoxicity against MDA‐MB‐453 cells, with an IC₅₀ value of 83.05 µg/mL. All extracts showed stronger inhibitory activity against acetylcholinesterase and butyrylcholinesterase compared to tacrine. The n‐hexane, ethyl acetate, and methanol extracts exhibited considerable antimicrobial activity against Enterococcus faecalis, approaching the level of vancomycin. Methanol extract possessed the highest DPPH scavenging and ferric reducing antioxidant power. These findings render A, sintenisii a promising source for the pharmaceutical, cosmetic, and food industries.