34 KB646 KB29 KB197320132008Kozjan, GašperZule, Janjaštevilka:86str. 51-58ISSN:0351-3114COBISSID:2311078URN:URN:NBN:SI:doc-9E0MYI4LslInštitut za gozdno in lesno gospodarstvoUniverza v Ljubljani, Biotehniška fakulteta, Oddelek za gozdarstvo & Oddelek za lesarstvoZbornik gozdarstva in lesarstvaantioksidantiantioxidantflavonoidiLarix spp.lignanimacesenpolifenoliPolifenoli v različnih vrstah macesna (Larix spp.)| Polyphenols in different larch (Larix spp.) species|Various types of polyphenolic compounds, such as lignans, oligolignans and flavonoids, which occur in different tissues of wood from the larch (Larix) genus, are presented in the article. Their biosynthesis, chemical structure and properties, including a distinctive antioxidative potential, are described. The methods of quantitative isolation from wood as well as their chemical characterization by means of sophisticated chromatographic analytical techniques are presented. It has been experimentally established that the highest concentrations of lignans and flavonoids are present in knots, branches and bark of trees. The most important flavonoid in larch tissues is taksifolin, while the predominating lignans in knots are secoisolariciresinol and less abundant lariciresinol and cycloisolariciresinol. The presence of polyphenols is crucial for wood durability, as these compounds represent efficient chemical protection of wood against biological decay. Due to high concentrations of bioactive lignans in knots of conifers, the latter represent a suitable source for technological production of valuable substancesV članku so predstavljene različne vrste polifenolnih spojin, kot so npr. lignani, oligolignani in flavonoidi, ki jih najdemo v tkivih macesnov, to je dreves iz rodu Larix. Opisana je njihova biosinteza, kemijska struktura in lastnosti, med katerimi je poudarjen predvsem njihov antioksidativni potencial. Predstavljene so metode kvantitativne izolacije iz drevesnih tkiv in kemijske karakterizacije z uporabo sodobnih kromatografskih analiznih tehnik. Raziskave so pokazale, da so največje koncentracije lignanov in flavonoidov v grčah, vejah in skorji dreves. Najpomembnejši med flavonoidi v tkivih macesnov je taksifolin. Glavni predstavnik lignanov, ki jih bomo našli predvsem v grčah, je sekoizolaricirezinol, poleg njega pa sta zastopana tudi laricirezinol in ciklolaricirezinol. Polifenoli so ključnega pomena za obstojnost lesa, saj pomenijo učinkovito kemijsko zaščito pred različnimi okužbami. Zaradi visokih koncentracij bioaktivnih lignanov v grčah iglavcev bi slednje lahko rabile kot vir za tehnološko pridobivanje teh dragocenih komponentTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaUniverza v Ljubljani, Biotehniška fakulteta