Kvasny Prum. 2006; 52(2): 38-40 | DOI: 10.18832/kp2006004

"Medicinal" compounds and molecular analysis of hop genes.Peer-reviewed article

Jaroslav MATOUŠEK

Ústav molekulární biologie rostlin AV ČR, Oddělení molekulární genetiky, České Budějovice

Recent analyses of hop (Humulus lupulus L.) secondary metabolites confirm a role of hop as a "molecular factory" crop being a rich source for new medicaments. New studies have particularly focused on prenylated flavonoids and to biochemical potential of Xanthohumol as a fascinating cancer-chemopreventive compound acting at all stages of carcinogenesis. The recent finding that Xanthohumol can be converted to the most potent plant phytoestrogen, 8-prenylnaringenin by human intestinal microflora, increases the availability of this compound from natural hop products.The first food supplement made from hop, so-called MenoHop has been released to the market as a real medicament beneficial for overcoming symptoms of human menopause. In parallel, there is an increasing effort to exploit molecular genetics to produce new hop varieties with higher content of prenylflavonoids. In our studies the oligofamily of hop genes called chs_H1, codetermining biosynthesis of prenylated chalcones has been identified. According to the analysis of promoter elements of chs_H1 genes, they are regulated by factors MYB R2R3.Two full R2R3 mybs designated HlMyb1 and HlMyb5, were cloned from Czech hop Osvald 72. In addition, even MYB factor from Arabidopsis called PAP1 has been shown in our studies to stimulate production of chalcones mediated by natural chs_H1 genes. Thus, myb biotechnology is expected to be a powerful tool to produce hop transgenotes as a new breeding materials.Recent analyses of hop (Humulus lupulus L.) secondary metabolites confirm a role of hop as a "molecular factory" crop being a rich source for new medicaments. New studies have particularly focused on prenylated flavonoids and to biochemical potential of Xanthohumol as a fascinating cancer-chemopreventive compound acting at all stages of carcinogenesis. The recent finding that Xanthohumol can be converted to the most potent plant phytoestrogen, 8-prenylnaringenin by human intestinal microflora, increases the availability of this compound from natural hop products.The first food supplement made from hop, so-called MenoHop has been released to the market as a real medicament beneficial for overcoming symptoms of human menopause. In parallel, there is an increasing effort to exploit molecular genetics to produce new hop varieties with higher content of prenylflavonoids. In our studies the oligofamily of hop genes called chs_H1, codetermining biosynthesis of prenylated chalcones has been identified. According to the analysis of promoter elements of chs_H1 genes, they are regulated by factors MYB R2R3.Two full R2R3 mybs designated HlMyb1 and HlMyb5, were cloned from Czech hop Osvald 72. In addition, even MYB factor from Arabidopsis called PAP1 has been shown in our studies to stimulate production of chalcones mediated by natural chs_H1 genes. Thus, myb biotechnology is expected to be a powerful tool to produce hop transgenotes as a new breeding materials.

Keywords: Saaz hop, "medicinal" beer, anticancerogenic compounds, regulatory factors, molecular biology, biotechnology

Published: February 1, 2006