title: Antimicrobial and antiradical activity of extracts obtained from leaves of three species of the genus pyrus.
abstract: In this study, extracts were obtained from leaves of Pyrus communis L., Pyrus elaeagrifolia Pall., and Pyrus pyrifolia (Bum.) Nak. These extracts were tested for antiradical and antibacterial activity, as well as for the amount of total phenolic compounds, hydroquinone and arbutin. The antiradical activity was measured using 2,2-diphenyl-1-picrylhydrazyl radical and antibacterial activity with the disk diffusion method. The amount of phenolic compounds was determined using Folin Ciocalteu's phenol reagent, but the amount of hydroquinone and arbutin was measured with high performance liquid chromatography. The strongest antiradical activity was observed for ethyl acetate extract from leaves of P. communis L., and the lowest for the poorly soluble fraction (precipitate) from leaves of P. elaeagrifolia Pall. The highest number of antiradical units per gram of raw materials was noted for leaves of P. communis. The strongest antibacterial activity was measured for ethyl acetate extracts. The calculation of Spearman rank correlation coefficients indicated the existence of a positive correlation between contents of hydroquinone in extracts and their antibacterial activity for almost all investigated bacterial strains. The strains of fungi such as Candida albicans and Saccharomyces cerevisiae were completely resistant to the action of extracts.
authors.affiliation: 1 Department of Pharmacognosy, Wrocław Medical University , Wrocław, Poland .
authors.forename: Sroka
authors.initials: S
authors.lastname: Zbigniew
authors.forename: Żbikowska
authors.initials: Ż
authors.lastname: Beata
authors.forename: Janicki
authors.initials: J
authors.lastname: Kamil
authors.forename: Franiczek
authors.initials: F
authors.lastname: Roman
authors.forename: Krzyżanowska
authors.initials: K
authors.lastname: Barbara
authors.forename: Dryś
authors.initials: D
authors.lastname: Andrzej
mesh_terms: D000085:Acetates; D000900:Anti-Bacterial Agents / Q000302:isolation & purification / Q000494:pharmacology*; D000975:Antioxidants / Q000302:isolation & purification / Q000494:pharmacology*; D001104:Arbutin / Q000302:isolation & purification / Q000494:pharmacology*; D001412:Bacillus subtilis / Q000187:drug effects / Q000254:growth & development; D001713:Biphenyl Compounds / Q000037:antagonists & inhibitors / Q000737:chemistry; D052978:Disk Diffusion Antimicrobial Tests; D004926:Escherichia coli / Q000187:drug effects / Q000254:growth & development; D016480:Helicobacter pylori / Q000187:drug effects / Q000254:growth & development; D006873:Hydroquinones / Q000302:isolation & purification / Q000494:pharmacology*; D010851:Picrates / Q000037:antagonists & inhibitors / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry; D018515:Plant Leaves / Q000737:chemistry; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000254:growth & development; D031989:Pyrus / Q000737:chemistry*; D012997:Solvents; D013045:Species Specificity; D013211:Staphylococcus aureus / Q000187:drug effects / Q000254:growth & development
chemical_list: D000085:Acetates; D000900:Anti-Bacterial Agents; D000975:Antioxidants; D001713:Biphenyl Compounds; D006873:Hydroquinones; D010851:Picrates; D010936:Plant Extracts; D012997:Solvents; C007650:ethyl acetate; D001104:Arbutin; C004931:1,1-diphenyl-2-picrylhydrazyl; C031927:hydroquinone