ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Secondary metabolites, antioxidant and anti-proteinase activities of methanolic extracts from cones of hop (Humulus lupulus L.) cultivars

Tibor Maliar, Peter Nemeček, Eva Ürgeová, Mária Maliarová, Vladimír Nesvadba, Karel Krofta, Katarína Vulganová, Erik Krošlák, and Ján Kraic

Department of Biotechnology, Faculty of Natural Sciences, University of SS. Cyril and Methodius, Trnava, Slovak Republic

E-mail: jan.kraic@ucm.sk

Abstract: Contents of polyphenols, flavonoids, bitter acids, α-bitter acids, xanthohumol, desmethylxanthohumol, essential oils, antioxidant activities, and inhibitory activities against trypsin, thrombin, urokinase, and papain were analysed in methanolic extracts prepared from the hope cones. Significant differences between extracts from eight hop cultivars in all measured parameters were found. Two cultivars—Agnus and Vital—could be designated as the very special, all possessing high content of bitter acids, α-acids, essential oils, xanthohumol, and desmethylxanthohumol. The other two cultivars—Bohemie and Sládek—had interesting inhibitory activities against analysed proteinases. Differences between cultivars were also in content of total polyphenols, total flavonoids, as well as in antioxidant activity. All analysed hop cultivars developed originally for brewing contained also secondary metabolites with valuable biological activities related to health conditions associated with antioxidant status and some pathophysiological agents of proteinase character.

Keywords: Humulus lupulus; Secondary metabolites; Polyphenols; Flavonoids; Antioxidant activity; Proteinase inhibition

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-016-0034-2

Chemical Papers 71 (1) 41–48 (2017)