8,874 research outputs found
Activation of proestrogens from hops (Humulus lupulus L.) by intestinal microbiota; Conversion of isoxanthohumol into 8-prenylnaringenin
Hop, an essential ingredient in most beers, contains a number of prenylflavonoids, among which 8-prenylnaringenin (8-PN) would be the most potent phytoestrogen currently known. Although a number of health effects are attributed to these compounds, only a few reports are available about the bioavailability of prenylflavonoids and the transformation potency of the intestinal microbial community. To test these transformations, four fecal samples were incubated with xanthohumol, isoxanthohumol (IX), and 8-PN. Upon incubation with IX, present in strong ales up to 4 mg/L, 36% was converted into 8-PN in one fecal sample and the estrogenic properties of the sample drastically increased. In an experiment with 12 fecal cultures, this conversion was observed in one-third of the samples, indicating the importance of interindividual variability in the intestinal microbial community. Eubacterium limosum was identified to be capable of this conversion (O-demethylation) of IX into 8-PN, and after strain selection, a conversion efficiency of 90% was achieved. Finally, strain supplementation to a nonconverting fecal sample led to rapid and high 8-PN production at only 1% (v/v) addition. Up to now, the concentration of 8-PN in beer was considered too low to affect human health. However, these results show that the activity of the intestinal microbial community could more than 10-fold increase the exposure concentration. Because prenylflavonoids are present in many beers with IX being the major constituent, the results raise the question whether moderate beer consumption might contribute to increased in vivo levels of 8-PN and even influence human health
Antiviral and antioxidant activity of a hydroalcoholic extract from Humulus lupulus L.
A hydroalcoholic extract from female inflorescences of Humulus lupulus L. (HOP extract) was evaluated for its anti-influenza activity. The ability of the extract to interfere with different phases of viral replication was assessed, as well as its effect on the intracellular redox state, being unbalanced versus the oxidative state in infected cells. The radical scavenging power, inhibition of lipoperoxidation, and ferric reducing activity were assayed as antioxidant mechanisms. A phytochemical characterization of the extract was also performed. We found that HOP extract significantly inhibited replication of various viral strains, at different time from infection. Viral replication was partly inhibited when virus was incubated with extract before infection, suggesting a direct effect on the virions. Since HOP extract was able to restore the reducing conditions of infected cells, by increasing glutathione content, its antiviral activity might be also due to an interference with redox-sensitive pathways required for viral replication. Accordingly, the extract exerted radical scavenging and reducing effects and inhibited lipoperoxidation and the tBOOH-induced cytotoxicity. At phytochemical analysis, different phenolics were identified, which altogether might contribute to HOP antiviral effect. In conclusion, our results highlighted anti-influenza and antioxidant properties of HOP extract, which encourage further in vivo studies to evaluate its possible application
Recommended from our members
Identification of candidate genes affecting Delta9-tetrahydrocannabinol biosynthesis in Cannabis sativa.
RNA isolated from the glands of a Delta(9)-tetrahydrocannabinolic acid (THCA)-producing strain of Cannabis sativa was used to generate a cDNA library containing over 100 000 expressed sequence tags (ESTs). Sequencing of over 2000 clones from the library resulted in the identification of over 1000 unigenes. Candidate genes for almost every step in the biochemical pathways leading from primary metabolites to THCA were identified. Quantitative PCR analysis suggested that many of the pathway genes are preferentially expressed in the glands. Hexanoyl-CoA, one of the metabolites required for THCA synthesis, could be made via either de novo fatty acids synthesis or via the breakdown of existing lipids. qPCR analysis supported the de novo pathway. Many of the ESTs encode transcription factors and two putative MYB genes were identified that were preferentially expressed in glands. Given the similarity of the Cannabis MYB genes to those in other species with known functions, these Cannabis MYBs may play roles in regulating gland development and THCA synthesis. Three candidates for the polyketide synthase (PKS) gene responsible for the first committed step in the pathway to THCA were characterized in more detail. One of these was identical to a previously reported chalcone synthase (CHS) and was found to have CHS activity. All three could use malonyl-CoA and hexanoyl-CoA as substrates, including the CHS, but reaction conditions were not identified that allowed for the production of olivetolic acid (the proposed product of the PKS activity needed for THCA synthesis). One of the PKS candidates was highly and specifically expressed in glands (relative to whole leaves) and, on the basis of these expression data, it is proposed to be the most likely PKS responsible for olivetolic acid synthesis in Cannabis glands
Биоморфологические аспекты интродукции и выращивания Humulus Lupulus L.
Статья посвящена использованию биоморфологических данных в интродукции и выращивании Humulus lupulus L.. Уточнено понятие "матка", применяемое в хмелеводстве. Показаны особенности организации подземной системы и побегообразования растения. Установлено, что для повышения качества посадочного материала в хмелеводческих хозяйствах необходимо использовать части сформировавшегося корневища с геофильным участкомyesБелгородский государственный университе
Hop Germplasm Study
Until now, commercial hop (Humulus lupulus L.) production has not occurred in the northeast (NE) region of the United States for 150 years. Vermont production peaked in 1860 when the state produced 289,690 kg of dried hops (Kennedy 1860). A combination of the spread of hop downy mildew, the expansion of production in western states, and prohibition laws from the 1920’s contributed to the decline of the 19th century NE hop industry. Today, the Pacific Northwest states of Washington, Oregon, and Idaho remain the dominant hop production sites of the U.S. However, hop production in non-traditional regions is growing and now accounts for over 2% of the total U.S. hop acreage (George, A., 2014). Nationally, there has been recent and unprecedented growth in the craft beer sector which has dramatically increased demand for local hop production
Phytotherapy in zoo animals
Phytotherapy is one of the oldest medical disciplines and was traditionally based on empiricism (Reichling et al., 2008). Nowadays, its use as an additional integral component of evidence based medicine is well accepted in human medicine (Finkelmann, 2009). Herbal remedies are generally characterised by a broad therapeutic index. They consist of multicomponent mixtures and act as multi-target drugs with pleiotropic effects. In Switzerland, veterinary phytotherapy has been relaunched in 2006 as a subunit of the Swiss Medical Society for Phytotherapy (SMGP-vet). Since 2012, the certificate of qualification in veterinary phytotherapy has been approved by the Swiss Veterinary Association (GST/SVS). Historically, one of the common approaches to gain insight into the medical effects of plants was self-medication. In non-human animals, self medication remains a controversial subject, because evidence is mostly anecdotal.
A few experimentally verified cases of self-medication support the theoretical expectation that animals can and do make specific foraging decisions that function specifically to remediate illness (Huffman and Caton, 2001; Villalba et al., 2006; Singer et al., 2009). In zoological medicine, this concept has first been implemented by primate keeping institutions. Permanent access to selected medicinal plants suggested self medication and helped maintain the health of certain primate species (Cousins, 2006)
- …
