title: The screening analysis of antiradical activity of some plant extracts.
abstract: BACKGROUND
  There is a need for screening studies in order to select plant extracts or plant raw materials with strong antiradical activity which could be used as medicines or substances to protect food from oxidation. In this paper the antiradical activities of some plant raw materials were investigated.
  
  
  METHODS
  The intensity of antiradical activity of extracts was investigated using DPPH* (1,1-diphenyl-2-picrylhydrazyl) radical as a substrate. The antiradical activity unit was defined and the number of antiradical activity units EAU(515) per 1 mg of plant extract and TAU(515) per 1 g of plant raw materials were calculated. Plant extracts were obtained with a methanol or methanol-water (1:1) solution.
  
  
  CONCLUSIONS
  The highest numbers of antiradical activity units EAU(515) were found for ethyl acetate extracts from the leaves of green and black tea. The lowest EAU(515) value was demonstrated for garlic extracts. When the number of activity units TAU(515) was calculated per 1 g of raw material, the highest value was found for the leaves of green tea, much lower for bee propolis and the leaves of black tea. On the basis of the presented results, green tea leaves, bee propolis, and the leaves of black tea could be considered as potential sources of extracts with strong antiradical activity.
authors.affiliation: Department of Pharmacognosy, Wrocław Medical University, Wrocław, Poland. zbsroka@farmgn.am.wroc.pl
authors.forename: Zbigniew
authors.initials: Z
authors.lastname: Sroka
mesh_terms: D000975:Antioxidants / Q000032:analysis* / Q000737:chemistry / Q000494:pharmacology; D001713:Biphenyl Compounds; D016166:Free Radical Scavengers / Q000032:analysis* / Q000737:chemistry / Q000494:pharmacology; D005609:Free Radicals / Q000032:analysis; D006801:Humans; D007202:Indicators and Reagents; D008517:Phytotherapy; D010851:Picrates; D010936:Plant Extracts / Q000032:analysis* / Q000737:chemistry / Q000494:pharmacology
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D005609:Free Radicals; D007202:Indicators and Reagents; D010851:Picrates; D010936:Plant Extracts; C004931:1,1-diphenyl-2-picrylhydrazyl