H. varium subsp. varium Willd. Bitkisi Toprak Üstü Sulu Ekstresi Üzerinde Fitokimyasal ve Biyolojik Etki Çalışmaları

Abstract

Hedysarum species have traditionally been used for their antidiabetic, wound-healing, antiarrhythmic, antihypercholesterolemic, laxative, and diuretic effects. Phytochemical studies have identified a wide variety of metabolites, predominantly flavonoids, which are considered responsible for their antioxidant and anti-inflammatory activities. In the present thesis, fractions (Fr. A–E2) obtained by polyamide column chromatography of the aqueous fraction (HSF) derived from the 80% ethanol extract of the aerial parts of Hedysarum varium subsp. varium were investigated. The HSF and its fractions were evaluated for their total phenolic and flavonoid contents, antioxidant, cytotoxic, anti-inflammatory, and neuroprotective activities. Antioxidant activity was assessed by DPPH and superoxide (SO) radical scavenging assays, cytotoxicity by the MTT assay, anti-inflammatory activity by NO quantification in LPS-stimulated RAW 264.7 cells, and neuroprotective activity using an H₂O₂-induced neurotoxicity model in SH-SY5Y cells. Among the fractions, Fr. E1 showed the strongest antioxidant activity, with IC₅₀ values of 26.3 and 82.9 µg/ml in the DPPH and SO assays, respectively, while all tested fractions exhibited significant anti-inflammatory and neuroprotective effects at 100 and 200 µg/ml compared with the control group. Rutin, nicotiflorin, and vestitol were isolated and structurally characterized. These phytochemical and biological findings indicate that H. varium subsp. varium is a promising natural source of pharmaceutically valuable bioactive compounds.