Thesis Type: Doctorate
Institution Of The Thesis: Bursa Uludağ University, FEN BİLİMLERİ ENSTİTÜSÜ, Turkey
Approval Date: 2021
Thesis Language: Turkish
Student: SİNEM GÜZELVARDAR
Supervisor: Özer Yılmaz
Abstract:
In this study, antioxidant potentials of 15 species that belonging to the genus Verbascum grown in our country were determined. These species are: V. serratifolium Hub.-Mor., V. basivelatum Hub.-Mor., V. bugulifolium Lam., V. yurtkuranianum Kaynak, Daşkın & Yılmaz, V. afyonense Hub-Mor., V. ovalifolium Donn ex Sims, V. prusianum Boiss., V. bithynicum Boiss., V. degenii Verh., V. olympicum Boiss., V. stenostachyum Hub.-Mor., V. vacillans Murb., V. gypsicola M. Vural & Aydoğdu, V. speciosum Schrader and V. cheiranthifolium Boiss. Methanol extracts were prepared from these species whose leaves were dried and DPPH radical scavenging activity, ABTS radical cation scavenging activity, reducing power potential, total phenolic substance analysis and total flavonoid substance amounts were determined. IC50 values were calculated to determine the DPPH and ABTS radical scavenging activity. According to both DPPH radical scavenging activity and ABTS radical cation scavenging activity experimental data, V. degenii, V. basivelatum, V. bithynicum, V. olympicum and V. prusianum species were determined as the species with the lowest IC50 values and therefore the highest antioxidant potential. These results are also supported by the reducing power potential, total phenolic substance and total flavonoid substance experiments. In general, among the species we investigated, V. yurtkuranianum, V. bugulifolium, V. ovalifolium and V. afyonense were the species with the lowest antioxidant content for the five antioxidant determination methods used.