Altın, Sevgi

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.

Sahin, Huseyin; Kaltalıoğlu, Kaan; Kandemir, Ali; Türkmen, Zafer; Bektaş, Ersan

This study was designed to evaluate the phenolic compounds and the in vitro antioxidant and antimicrobial activities of Onobrychis nitida, Hedysarum cappadocicum, Ebenus laguroides and Ebenus macrophylla which are medicinal plants and endemic for the flora of Turkey. The RP-HPLC-DAD (reverse phasehigh performance liquid chromatography with a diode array detector) was used to evaluate the phenolic contents. The antioxidant properties were determined to use total phenolic content (TPC), ferric reducing antioxidant power (FRAP), and DPPH• radical scavenging activity assays. Antibacterial tests were performed against 11 different microorganisms by using the microwell dilution method. Each of the plant extracts were confirmed by bioactive assays which demonstrated a significant activity due to different chemical characteristics. Especially, rutin was the dominant component in Ebenus species with 19.434-11.808 mg phenolic/g extract. While the highest phenolic content (101.73 mg gallic acid equivalent/g extract) was observed in O. nitida, the highest FRAP value was in E. laguroides (719.09 μM FeSO4.7H2O equivalent), and the strongest DPPH degree was in the E. macrophylla extract with IC50: 69.45 μg/mL, respectively. Although plant extracts didn’t have efficient values for antimicrobial activity, the slight effect was arisen in O. nitida against B. subtilis and S. aureus. The results showed that all the extracts could be used in pharmacological or dietary applications due to their valuable properties