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  • Küçük Resim
    Öğe
    Antioxidant activity of bisbenzylisoquinoline alkaloids from Stephania rotunda: cepharanthine and fangchinoline
    (Taylor & Francis Ltd, 2010) Gülçin, İlhami; Elias, Riad; Gepdiremen, Akçahan; Chea, Aun; Topal, Fevzi
    In the present study, we determined the antioxidant activity of cepharanthine and fangchinoline from Stephania rotunda by performing different in vitro antioxidant assays, including 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging, N,N-dimethyl-p-phenylenediamine dihydrochloride (DMPD) radical scavenging, superoxide anion (O-2(center dot-)) radical scavenging, hydrogen peroxide scavenging, total antioxidant activity, reducing power, and ferrous ion (Fe2+) chelating activities. Cepharanthine and fangchinoline showed 94.6 and 93.3% inhibition on lipid peroxidation of linoleic acid emulsion at 30 mu g/mL concentration, respectively. On the other hand, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), alpha-tocopherol, and trolox indicated inhibitions of 83.3, 92.2, 72.4, and 81.3% on peroxidation of linoleic acid emulsion at the same concentration (30 mu g/mL), respectively. According to the results, cepharanthine and fangchinoline have effective antioxidant and radical scavenging activity.
  • Küçük Resim
    Öğe
    Apoptotic, antioxidant and antiradical effects of majdine and isomajdine from Vinca herbacea Waldst. and kit
    (Taylor & Francis Ltd, 2012) Gülçin, İlhami; Beydemir, Şükrü; Topal, Fevzi; Gagua, Natia; Bakuridze, Aliko; Bayram, Recep; Gepdiremen, Akçahan
    In the present study, apoptotic, antioxidant and antiradical effects of majdine and isomajdine from Vinca herbacea Waldst. and Kit were studied. For testing the possible apoptotic effects of majdine and isomajdine from V. herbacea, DNA fragmentation assay was conducted on the rat brain cortical tissue homogenates, in vitro. Also their possible effects on mitochondrial activity were tested by using the same tissue samples of rats. In addition, the antioxidant activity of isomajdine and majdine was determined using various in vitro antioxidant assays, including 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS(center dot+)) radical scavenging and N,N-dimethyl-p-phenylenediamine (DMPD center dot+) radical scavenging, ferric ions (Fe3+) and cupric ions (Cu2+) reducing abilities and ferrous ions (Fe2+) chelating activity. On the other hand, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), alpha-tocopherol and trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid) were used as reference antioxidants.