In vitro antiplasmodial activity of prenylated chalcone derivatives of hops (Humulus lupulus) and their interaction with haemin

Abstract

The results demonstrate for the first time the ability of chalcone derivatives to interfere with the haemin-degradation process of P. falciparum. This effect might contribute to their antiplasmodial activity. Nevertheless, as one compound showed inhibition of P. falciparum without being able to interact with GSH-dependent haemin degradation, other modes of action must add to the observed antiparasitic activity of hop chalcones.

Broad spectrum antiinfective potential of xanthohumol from hop (Humulus lupulus L.) in comparison with activities of other hop constituents and xanthohumol metabolites

“…XN (4) as well as a microbial transformation product (7), obtained by incubation of XN (4) with cultures of the fungus Pichia membranifaciens (ATCC 2254), were active against both strains, with IC 50 values of 3.3 lg/ml (9.3 lM) and 4.1 lg/ml (11.1 lM) against strain D6, and 1.0 lg/ml (2.8 lM) and 1.8 lg/ml (4.9 lM) against strain W2, respectively. Antimalarial activity was confirmed in a recent study by Frölich et al [26]. In vitro antiplasmodial activity of XN (4) and seven prenylated chalcones was evaluated against the chloroquine-sensitive strain poW and the multiresistant clone Dd2, using a [ 3 H]-hypoxanthine incorporation assay.…”

“…In vitro antiplasmodial activity of XN (4) and seven prenylated chalcones was evaluated against the chloroquine-sensitive strain poW and the multiresistant clone Dd2, using a [ 3 H]-hypoxanthine incorporation assay. In addition, the influence of the compounds on glutathione (GSH)-dependent haemin degradation was analyzed to determine its contribution to the antimalarial effect of chalcones [26]. Of the eight compounds tested, four compounds, i.e.…”

“…Noteworthy the pyrano-derivative (9) lacking the free OH-group in position 29 was unable to interfere with haemin degradation, although it potently inhibited replication of P. falciparum. Therefore, other modes of action including the inhibition of cysteine proteases have to be considered [26].…”

Effect of xanthohumol on melanogenesis in B16 melanoma cells

“…XH is an antioxidant (Miranda et al, 2000) and a broadspectrum cancer chemopreventive agent that prevents carcinogenesis in the initiation, promotion, and progression phase (Gerhauser et al, 2002;Pan et al, 2005;Plazar et al, 2007). It also inhibits adipogenesis (Yang et al, 2007) and osteoporosis (Tobe et al, 1997), and potentially influences AIDS (Wang et al, 2004) and malaria (Frolich et al, 2005), at least in vitro. However, to our knowledge, there is no report about the effect of XH on melanogenesis.…”

Synthesis and Antimicrobial Activity of Some Novel Chalcones of 3-Acetyl Pyridine and their Pyrimidine Derivatives

“…The presence of a reactive, unsaturated keto function in chalcones is found to be responsible for their antimicrobial activity, which may be altered depending on the type and position of substituent on the rings. In the present communication we report the reaction of 3-acetylpyridine with different aromatic aldehydes (2 a-g ) to form chalcones [1][2][3][4][5][6][7][8][9][10][11][12][13] (3 a-g ) in the presence of alkali. The resulting chalcones after purification and characterization by physical and spectral methods have been successfully converted into substituted pyrimidines [14][15][16][17][18][19] (4 a-g ) by reaction with guanidine hydrochloride.…”