Accumulation of metals and selected nutritional parameters in the field-grown chamomile anthodia

Accumulation of metals and selected nutritional parameters of chamomile (Matricaria chamomilla) anthodia cultured under natural condition on an experimental field in Kosice (Slovak Republic) were studied. Two official cultivars (diploid 'Novbona' and tetraploid 'Lutea') and two ontogenetic phases of anthodia ('bud' and 'flower') were compared. K, Ca, Mg, Al, Cu, Cr, Hg and Cd were more accumulated in both bud and flower of diploid plants while accumulation of Fe, Zn, Ni and Pb was ploidy-independent. Bioaccumulation factor was lower than one for toxic metals, indicating that chamomile is an excluder. Tetraploid plants contained lower concentrations of amino acids but higher concentrations of phenolic acids compared to diploid plants. Among phenolic acids, caffeic and vanillic acids were mainly present in the glycosidic form. Reducing sugars (glucose equivalents), total soluble phenols, sum of flavonols, individual flavonols (quercetin and kaempferol), apigenin and herniarin were more accumulated in anthodia of tetraploid plants. Our data indicate that increase in ploidy level reduces accumulation of toxic metals and amino acids but enhances accumulation of phenolic metabolites. Thus polyploidisation is a good tool to achieve safer chamomile cultivars for pharmaceutical purposes. (C) 2011 Elsevier Ltd. All rights reserved.