title: Evaluation of antioxidant, enzyme inhibition, and cytotoxic activity of three anthraquinones (alizarin, purpurin, and quinizarin).
abstract: OBJECTIVE
  The aim of this work was to investigate the cytotoxic, antioxidative, and enzyme inhibition effects of alizarin, quinizarin, and purpurin, which are anthraquinones (AQ).
  
  
  METHODS
  Cytotoxic effects were evaluated with cell inhibition rate by 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide assay. Different chemical assays, including free radical scavenging activity (1,1-diphenyl-2-picrylhydrazyl and 2,2-azino-bis(3-ethylbenzothiazloine-6-sulfonic acid)), phosphomolybdenum and reducing power (ferric reducing antioxidant power and cupric ion reducing activity), were used to evaluate the antioxidant properties. Moreover, enzyme inhibitory activities were analyzed against acetylcholinesterase, butrylcholinesterase, tyrosinase, α-amylase, and α-glucosidase.
  
  
  RESULTS
  These components have antioxidant and enzyme inhibition activity. Especially, purpurin showed the strongest antioxidant and good enzyme inhibitory effects. According to our cytotoxicity results, alizarin, purpurin, and quinizarin induced dose- and time-dependent cell proliferation. Furthermore, when we applied AQs with mitomycin C (MC) on L929 cell line, we demonstrated that cell proliferation in MC-AQ groups compared with MC group was increased. The most effective component was alizarin at 100 µM concentration. These AQs showed positive effects on L929 cell lines with high half-maximal inhibitory concentration values.
  
  
  CONCLUSIONS
  Our results demonstrate that AQs may be used as antioxidative compounds in food and medicinal applications.
authors.affiliation: Department of Biology, Faculty of Science, Selcuk University, Konya, Turkey gokhanzengin@selcuk.edu.tr.
authors.forename: G
authors.initials: G
authors.lastname: Zengin
authors.affiliation: Department of Biology, Faculty of Science and Art, Fatih University, Istanbul, Turkey.
authors.forename: N S
authors.initials: NS
authors.lastname: Degirmenci
authors.affiliation: Department of Medical Biology, Faculty of Medicine, Fatih University, Istanbul, Turkey.
authors.forename: L
authors.initials: L
authors.lastname: Alpsoy
authors.affiliation: Department of Biology, Faculty of Science, Selcuk University, Konya, Turkey.
authors.forename: A
authors.initials: A
authors.lastname: Aktumsek
mesh_terms: D000818:Animals; D000880:Anthraquinones / Q000494:pharmacology* / Q000633:toxicity; D000975:Antioxidants / Q000494:pharmacology* / Q000633:toxicity; D001681:Biological Assay; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology* / Q000633:toxicity; D005347:Fibroblasts / Q000187:drug effects*; D005503:Food Additives; D020128:Inhibitory Concentration 50; D051379:Mice
chemical_list: D000880:Anthraquinones; D000975:Antioxidants; D004791:Enzyme Inhibitors; D005503:Food Additives; C010078:alizarin; C034890:1,4-dihydroxyanthraquinone; C511975:purpurin anthraquinone
keywords: Alizarin; cytotoxic effect; enzyme inhibition; purpurin; quinizarin