The pharmacognosy of Humulus lupulus L. (hops) with an emphasis on estrogenic properties

A droplet vitrification cryopreservation protocol for conservation of hops (Humulus lupulus) genetic resources

Hops (Humulus lupulus L.) is essentially used in the brewing industry as it contributes to flavor, and aroma of beer. However, the genetic diversity of hops is increasingly threatened by diseases, environmental changes, and urbanization. Cryopreservation has emerged as a pivotal strategy for safeguarding and maintaining the genetic diversity of hops. The present work presents a comprehensive study on the cryopreservation of hops, focusing on the development and optimization of a droplet vitrification based cryopreservation protocol. Shoot tips excised from one month old in vitro cultures were precultured on 0.3 M sucrose, dehydrated in a loading solution followed by treatment with PVS2 solution for different durations. Significant effect of PVS2 dehydration was observed on post-thaw survival and regeneration after cryoconservation with maximum 50% post-thaw regeneration observed in shoot tips dehydrated in PVS2 for 30 min. Genetic fidelity of the regenerated plants was confirmed using 30 ISSR markers. Reproducibility of the developed protocol was tested on seven other accessions and post thaw regeneration ranging from 43 to 70% was observed across the accessions. The present study reports a highly efficient protocol for conservation of hops germplasm. The results indicate that droplet vitrification can be used as a reliable and sustainable approach for hop genetic preservation, with high survival rates and minimal genetic alterations observed in cryopreserved samples. To the best of our knowledge, this is the first report on DV based cryopreservation of hops germplasm.

Xanthohumol, a prenylated flavonoid from hops (Humulus lupulus L.) exerts multidirectional pro-healing properties towards damaged zebrafish hair cells by regulating the innate immune response

Xanthohumol (XN) is a prominent prenylated flavonoid present in the hop plant (Humulus lupulus L.). Despite undoubted pro-healing properties of hop plant, there is still a need for clinical investigations confirming these effects as well as the underlying molecular mechanisms. The present study was designed to (1) establish the role of XN in non-invasive inflammation induced by chemical damage to zebrafish hair cells, (2) clarify if it influences cell injury severity, neutrophil migration, macrophage activation, cell regeneration, and (3) find out whether it modulates the gene expression profile of chosen immune and stress response markers. All experiments were performed on 3 dpf zebrafish larvae. After fertilization the embryos were transferred to appropriate XN solutions (0.1 μM, 0.3 μM and 0.5 μM). The 40 min 10 μM CuSO4 exposure evoked severe damage to posterior lateral line hair cells triggering a robust acute inflammatory response. Four readouts were selected as the indicators of XN role in the process of inflammation: 1) hair cell death, 2) neutrophil migration towards damaged hair cells, 3) macrophage activation and recruitment to damaged hair cells, 4) hair cell regeneration. The assessments involved in vivo confocal microscopy imaging and qPCR based molecular analysis. It was demonstrated that XN (1) influences death pathway of damaged hair cells by redirecting their severe necrotic phenotype into apoptotic one, (2) impacts the immune response via regulating neutrophil migration, macrophage recruitment and activation (3) modulates gene expression of immune system markers and (4) accelerates hair cell regeneration.

Safety Assessment of Hops as Used in Cosmetics

The Expert Panel for Cosmetic Ingredient Safety (Panel) assessed the safety of Humulus Lupulus (Hops) Extract (reported functions include antimicrobial agent and hair conditioning agent) and Humulus Lupulus (Hops) Oil (reported function is fragrance). The Panel reviewed the relevant data related to these ingredients. Because final product formulations may contain multiple botanicals, each containing the same constituents of concern, formulators are advised to be aware of these constituents and to avoid reaching levels that may be hazardous to consumers. For these ingredients, the Panel was concerned about the presence of 8-prenylnaringenin, β-myrcene, and quercetin in cosmetics, which could result in estrogenic effects, dermal irritation, and genotoxicity, respectively. Industry should use current good manufacturing practices to limit impurities and constituents of concern. The Panel concluded that Humulus Lupulus (Hops) Extract and Humulus Lupulus (Hops) Oil are safe in cosmetics in the present practices of use and concentration when formulated to be non-sensitizing.

Fractionation of High-Value Compounds from Hops Using an Optimised Sequential Extraction Procedure

This study describes the development and optimisation of a process for the extraction and fractionation of high-value compounds from hops. Firstly, the efficacy of ten organic solvents was compared for performing the initial solid-liquid extraction of compounds from hop pellets with subsequent fractionation steps. A methanol-dichloromethane mixture was selected and the extraction variables were optimised in order to maximise the recovery of valuable hop compounds separated into different streams (α- and β-acids in soft resins, xanthohumol in hard resins, and phenolics in spent solids) after fractionation steps. The optimisation results showed that extraction of hop pellets performed at room temperature with 19.7% (v/v) methanol for 89 min yielded recoveries of 86.57% α-acids and 89.14% β-acids in soft resins, 78.48% xanthohumol in hard resins and 67.10% phenolics in spent solids. These conditions were successfully validated using six hop varieties. Moreover, the antioxidant properties of all recovered fractions were compared and the soft resins showed the highest antioxidant activities, reaching values of 3.91 ± 0.10 g AAE/100 g for ferric reducing power (FRAP) and 0.10 ± 0.01 mg/mL for 50% of radical scavenging activity (EC50). The optimised sequential extraction could serve as a basis for larger scale-up for industrial production.

Identification of colupulone and lupulone as the main contributors to the antibacterial activity of hop extracts using activity-guided fractionation and metabolome analysis

Hop is widely used in beer brewing and as a medicinal product. The present study comprehensively analyzed the main molecular determinants of the antibacterial activity of hop extracts. Minimum inhibitory concentrations (MIC) against Bacillus subtilis between 31.25 and 250 µg/mL were found in the ethanolic extracts of five hop varieties for beer brewing, but not in the tea hop sample. Activity-guided fractionation revealed the highest antibacterial activity for lupulone and adlupulone (MIC 0.98 µg/mL). Metabolome profiling and subsequent multistep statistical analysis detected 33 metabolites out of 1826 features to be associated with the antibacterial activity including humulone, adhumulone, colupulone, lupulone, and adlupulone. Xanthohumol, the three humulone- and three lupulone congeners were quantified in the hop extracts by a validated ultrahigh-performance liquid chromatography-mass spectrometry method. Considering concentrations and MICs, colupulone and lupulone were identified as major contributors to the antibacterial activity of hop extract with the highest antibacterial activity values (concentration/MIC) of 1.59 and 2.56.

Effect of Humulus lupulus L. (Hop) on Postmenopausal Sexual Dysfunction: A Randomized Clinical Trial

Objective

Female sexual dysfunction is a common distressing problem among women, which may result from reducing circulating endogenous estrogen. Humulus lupulus L. (hop) has antioxidant, anti-inflammatory, anticancer, and estrogenic properties. Therefore, this study aimed to assess the efficacy of hop on postmenopausal sexual dysfunction.

Methods

In the current randomized clinical trial, study populations consisted of 63 postmenopausal women who were randomly categorized into two groups. In the hop group (N = 33), women received the vaginal gel containing Hop extract every day for seven days and then continued for two months, twice weekly. In the estradiol group (N = 30), women were treated with vaginal estradiol (0.625 mg) over two 28-day cycles (21 days of therapy and seven days rest). The sexual function was evaluated using the Female Sexual Function Index (FSFI) questionnaire before and after intervention.

Results

No statistically significant differences in FSFI scores (sexual desire, sexual arousal, vaginal lubrication, satisfaction, orgasm, sexual pain, and total FSFI) (P > 0.05) were noticed after treatment between the hop and estradiol groups.

Conclusion

Vaginal hop was as effective as estradiol in improving the sexual dysfunction among postmenopausal women with no adverse events. This trial is registered with IRCT20210405050859N1.

An Updated Review of the Genus Humulus: A Valuable Source of Bioactive Compounds for Health and Disease Prevention

The medicinal potential of hop (Humulus lupulus L.) is widely cited in ancient literature and is also allowed in several official pharmacopoeias for the treatment of a variety of ailments, mainly related to anxiety states. This is due to the plethora of phytoconstituents (e.g., bitter acids, polyphenols, prenyl flavonoids) present in the female inflorescences, commonly known as cones or strobili, endowed with anti-inflammatory, antioxidant, antimicrobial, and phytoestrogen activities. Hop has recently attracted the interest of the scientific community due to the presence of xanthohumol, whose strong anti-cancer activity against various types of cancer cells has been well documented, and for the presence of 8-prenyl naringenin, the most potent known phytoestrogen. Studies in the literature have also shown that hop compounds can hinder numerous signalling pathways, including ERK1/2 phosphorylation, regulation of AP-1 activity, PI3K-Akt, and nuclear factor NF-κB, which are the main targets of the antiproliferative action of bitter acids and prenylflavonoids. In light of these considerations, the aim of this review was to provide an up-to-date overview of the main biologically active compounds found in hops, as well as their in vitro and in vivo applications for human health and disease prevention. To this end, a quantitative literature analysis approach was used, using VOSviewer software to extract and process Scopus bibliometric data. In addition, data on the pharmacokinetics of bioactive hop compounds and clinical studies in the literature were analysed. To make the information more complete, studies on the beneficial properties of the other two species belonging to the genus Humulus, H. japonicus and H. yunnanensis, were also reviewed for the first time.

Effects of a Nutritional Supplement (DìRelaxTM) on Anxiety in Dogs in a Randomized Control Trial Design

Simple Summary

The effects of a nutraceutical product, DìRelax^TM, were tested in a cohort of anxious dogs by the C-BARQ questionnaire to assess the presence of problematic behaviors, and by the impossible task paradigm, an experimental procedure to explore dogs’ cognitive performance following an expectancy frustration. Hematological and biochemical analyses showed no adverse effects. The treatment with DìRelax^TM showed a positive effect on the dog’s performances, with some of the behaviors appearing improved. The results suggested that DiRelax^TM may have some ameliorative effect on the cognitive performances of anxious dogs.

Abstract

This study aimed to investigate the efficacy of DìRelax^TM, a nutraceutical formulated to reduce anxiety in dogs, using a randomized controlled trial (RCT) design. The C-BARQ questionnaire, some clinical investigations, and the impossible task test were performed in dogs before and after treatment. The C-BARQ questionnaire is particularly useful for assessing the frequency and severity of problematic behaviors. The impossible task paradigm provides insight into the decision-making processes in the realm of expectancy frustration. Results showed an ameliorative effect on the performances of treated dogs during the solvable phases, with a significant decrease in the time needed to solve the task. No behavioral difference was found between treated and untreated anxious dogs during the unsolvable phase. According to the results from the C-BARQ questionnaire, some of the behaviors appeared to improve. Clinical investigations, including a complete blood cell count and blood chemistry, showed no difference between groups, thus suggesting the safety of the product. In general, this study suggests that DìRelax^TM can be safely administered with no adverse effects and can exercise a beneficial effect on anxious dogs by enhancing their cognitive abilities, but further studies should investigate the best method of administration.

The Influence of Hop Phenolic Compounds on Dry Hopping Beer Quality

Background: The article considers the phenolic hop compounds’ effect on the quality indicators of finished beer. The topic under consideration is relevant since it touches on the beer matrix colloidal stability when compounds with potential destabilizing activity are introduced into it from the outside. Methods: The industrial beer samples’ quality was assessed by industry-accepted methods and using instrumental analysis methods (high-performance liquid chromatography methods—HPLC). The obtained statistical data were processed by the Statistics program (Microsoft Corporation, Redmond, WA, USA, 2006). Results: The study made it possible to make assumptions about the functional dependence of the iso-α-bitter resins and isoxanthohumol content in beer samples. Mathematical analysis indicate interactions between protein molecules and different malted grain and hop compounds are involved in beer structure, in contrast to dry hopped beer, where iso-a-bitter resins, protein, and coloring compounds were significant, with a lower coefficient of determination. The main role of rutin in the descriptor hop bitterness has been established in kettle beer hopping technology, and catechin in dry beer hopping technology, respectively. The important role of soluble nitrogen and β-glucan dextrins in the perception of sensory descriptors of various technologies’ beers, as well as phenolic compounds in relation to the formation of bitterness and astringency of beer of classical technology and cold hopping, has been shown. Conclusions: The obtained mathematical relationships allow predicting the resulting beer quality and also make it possible to create the desired flavor profiles.

Efficacy and Safety of a Standardized Soy and Hop Extract on Menopausal Symptoms: A 12-Week, Multicenter, Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Objectives: Soy and hop extracts have been investigated as alternatives for hormone replacement therapy. However, their combined efficacy is not known. We investigated the efficacy and safety of a combined soy and hop extract on postmenopausal symptoms. Design: Double-blinded, randomized controlled trial. Settings/Location: Gynecological outpatient clinic of tertiary hospital. Subjects: Seventy-eight women with moderate or severe menopausal symptoms assessed as modified Kupperman Menopoausal Index (KMI) scores >20. Interventions: They received either a combined soy and hop extract (n = 38) or placebo (n = 40). Outcome measures: Menopausal symptoms were evaluated through self-reporting of modified Kupperman Menopausal Index (KMI) scores at baseline and after 6 and 12 weeks. We assessed serum levels of bone metabolism biomarkers, ultrasonographic parameters, hormone profiles, compliance, and safety. Results: After 12 weeks of the treatment, treatment group scores decreased by 20.61 points compared with 14.80 points in the placebo group (p < 0.05). Fatigue, paresthesia, arthralgia, and myalgia, palpitation and vaginal dryness significantly improved more in the treatment group compared with the placebo group after 12 weeks (p < 0.05). Urine N-telopeptide in participants ≥50 years in the treatment group showed a reduced increase. Endometrial thickness and hormonal profiles did not show significant changes in either group. No serious adverse events were reported. Conclusion: The results suggest that 190 mg of combined soy and hop extract is safe and effective for improvement of menopausal symptoms. CRIS No.: KCT0006019.

Preparation of Hop Estrogen-Active Material for Production of Food Supplements

In recent years, the interest in the health-promoting effects of hop prenylflavonoids, especially its estrogenic effects, has grown. Unfortunately, one of the most potent phytoestrogens identified so far, 8-prenylnaringenin, is only a minor component of hops, so its isolation from hop materials for the production of estrogenically active food supplements has proved to be problematic. The aim of this study was to optimize the conditions (e.g., temperature, the length of the process and the amount of the catalyst) to produce 8-prenylnaringenin-rich material by the magnesium oxide-catalyzed thermal isomerization of desmethylxanthohumol. Under these optimized conditions, the yield of 8-prenylnaringenin was 29 mg per 100 gDW of product, corresponding to a >70% increase in its content relative to the starting material. This process may be applied in the production of functional foods or food supplements rich in 8-prenylnaringenin, which may then be utilized in therapeutic agents to help alleviate the symptoms of menopausal disorders.

Dataset for Hop varieties classification

Humulus lupulus L., also known as hops, is a vine whose flowers are a major component in brewing. It delivers flavor, bitterness, and aroma to beer and also aids in foam stabilization. Furthermore, it plays an important role in beer conservation due to its antimicrobial and antioxidant properties, which have recently been studied for food preservation. Hops can also be found in the production of cosmetics and is considered healthy food.

There are more than 250 cataloged varieties of hops, and among the main attributes that differ from each other are alpha-acids, beta-acids, and essential oils. Those components give the beer a unique combination of characteristics, and may even influence its category. There are many ways to identify the hop variety from its acids and essential oils using methods such as chromatography, mass spectrometry, capillary electrophoresis, and nuclear magnetic resonance. However, these methods demand expensive and complex equipment, inaccessible or unavailable to most beer producers.

In this work, we present a database that includes 1592 images of hop leaves, from 12 popular hop varieties in southeastern Brazil. From these images, it is possible to explore methods of pattern recognition and machine learning to classify hop varieties

Key Enzymes Involved in the Synthesis of Hops Phytochemical Compounds: From Structure, Functions to Applications

Humulus lupulus L. is an essential source of aroma compounds, hop bitter acids, and xanthohumol derivatives mainly exploited as flavourings in beer brewing and with demonstrated potential for the treatment of certain diseases. To acquire a comprehensive understanding of the biosynthesis of these compounds, the primary enzymes involved in the three major pathways of hops' phytochemical composition are herein critically summarized. Hops' phytochemical components impart bitterness, aroma, and antioxidant activity to beers. The biosynthesis pathways have been extensively studied and enzymes play essential roles in the processes. Here, we introduced the enzymes involved in the biosynthesis of hop bitter acids, monoterpenes and xanthohumol derivatives, including the branched-chain aminotransferase (BCAT), branched-chain keto-acid dehydrogenase (BCKDH), carboxyl CoA ligase (CCL), valerophenone synthase (VPS), prenyltransferase (PT), 1-deoxyxylulose-5-phosphate synthase (DXS), 4-hydroxy-3-methylbut-2-enyl diphosphate reductase (HDR), Geranyl diphosphate synthase (GPPS), monoterpene synthase enzymes (MTS), cinnamate 4-hydroxylase (C4H), chalcone synthase (CHS_H1), chalcone isomerase (CHI)-like proteins (CHIL), and O-methyltransferase (OMT1). Furthermore, research advancements of each enzyme in terms of reaction conditions, substrate recognition, enzyme structures, and use in engineered microbes are described in depth. Hence, an extensive review of the key enzymes involved in the phytochemical compounds of hops will provide fundamentals for their applications in beer production.

Performance of Tetranychus urticae (Acari: Tetranychidae) on three hop cultivars (Humulus lupulus)

Tetranychus urticae Koch (Acari: Tetranychidae) is a major pest species in numerous crops including hop (Humulus lupulus L.). Substantial T. urticae infestation was observed to occur in this recently introduced crop in Brazil. The adoption of less suitable cultivars to the pest species is highly desirable for integrated pest management. We used free-choice trials and two-sex life table analysis to determine the preference and population growth of T. urticae under laboratory conditions using three of hop cultivars currently expanding in Brazil (Mantiqueira, Victoria, and Yakima Gold). We also estimated the density of non-glandular trichomes and lupulin glands found on the abaxial leaf surface of these cultivars and correlated them with performance parameters of T. urticae. Mantiqueira appeared to be the least preferred by adult females for attractiveness and oviposition suggesting existence of antixenosis on this cultivar. Female immature stages developed slower on Yakima Gold and Mantiqueira, but no difference was observed between the latter and Victoria. Fecundity and longevity were significantly lower on Mantiqueira than on Victoria and Yakima Gold. No significant differences were observed among cultivars for intrinsic rate of increase (r), finite rate of increase (λ), and net rate of reproduction (R₀), suggesting the absence of antibiosis. Although, lupilin gland densities were higher on Mantiqueira and Yakima Gold than on Victoria, no significant correlations were observed between these defensive traits and performance parameters of T. urticae. However, 30-day population simulations of T. urticae suggest that Yakima Gold is the least susceptible, Mantiqueira is moderately susceptible, and Victoria is highly susceptible.

High Genetic Diversity and Low Population Differentiation in Wild Hop (Humulus lupulus L.) from Croatia

Hop (Humulus lupulus L.) is used in the brewing industry as a source of compounds responsible for the bitterness, aroma, and preservative properties of beer. In this study, we used microsatellite markers to investigate genetic diversity and genetic differentiation of wild hop populations sampled in the northwestern part of Croatia. Analysis of 12 microsatellite loci revealed high diversity and weak population differentiation among wild hop populations. A total of 152 alleles were determined with an average of 12.67 alleles per locus. Observed heterozygosity ranged from 0.689 to 0.839 (average 0.767) and expected heterozygosity ranged from 0.725 to 0.789 (average 0.760). A total of 38 private alleles were detected. The data suggest that H. lupulus populations are not affected by recent bottlenecks. The degree of genetic differentiation among populations was low and not significant for most pairwise FST values, except for the pair of geographically most distant populations. The results did not indicate the existence of genetic structure among the sampled populations. The high genetic diversity and low differentiation among populations, combined with the absence of isolation by distance, indicate the existence of substantial gene flow among wild hop populations. Therefore, extensive sampling per population is clearly required to assess the genetic diversity of hop populations. Sampling strategies involving sampling across a large number of localities represented by only a few samples could lead to erroneous conclusions.

Beer Polyphenols—Bitterness, Astringency, and Off-Flavors

The acceptance of beer among consumers is most influenced by the taste and aroma. Polyphenols are widely responsible for both. Whereas polyphenols do not always result in a positive flavor and taste, they can surely impart certain off-flavors, which will be mentioned in this paper. However, the aftertaste is an important component of the beer-tasting experience and acceptance. The aftertaste, including astringency, may largely influence consumers’ consumption preference and behavior. Bitterness is one of the main, desirable characteristics of beer, but to an untrained consumer, it can often be mistaken with astringency. This review aims to describe the differences between these two properties. Both attributes derive from the same beer components, polyphenols from barley and hop, but there is a distinctive difference between them. To understand the complexity of bitterness and astringency, polyphenols behavior, characteristics, and stability during the brewing process are also described in this review.

Systemically Achievable Doses of Beer Flavonoids Induce Estrogenicity in Human Endometrial Cells and Cause Synergistic Effects With Selected Pesticides

Some prenylated polyphenols originating from hops, which are thus natural constituents of beer, have been discussed critically for their agonistic potential toward estrogen receptors. So far, little attention has been attributed to the fact that humans are typically not exposed to isolated compounds, but to mixtures which for example might comprise in addition to hop flavonoids further xenoestrogens, e.g., certain pesticides used for plant protection of hops and barley. Thus, we used the alkaline phosphatase assay to assess combinatory estrogenic effects of three signature compounds – xanthohumol, 8-prenylnaringenin and iso-xanthohumol–on Ishikawa cells in a combination that resembled the concentration ratios observable in beer. Moreover, we added this natural flavonoid pattern to a mixture of representative estrogenic pesticides to assess their combined effects. Using state-of-the-art statistical tools, we observed cumulative to slightly synergistic effects between isolated flavonoids as well as the flavonoid and the pesticide mixture. Of potential importance, these effects were found at low nanomolar hop polyphenol concentrations that one can reasonably expect to occur in vivo after the consumption of strongly hopped beer. Taken together, our results imply that cumulative/synergistic estrogenicity should be explored in detail and urgently be incorporated into risk assessment of prenylated chalcones.

Identification and characterization of long non-coding RNA and their response against citrus bark cracking viroid infection in Humulus lupulus

Long non-coding RNAs (lncRNAs) are a highly heterogeneous class of non-protein-encoding transcripts that play an essential regulatory role in diverse biological processes, including stress responses. The severe stunting disease caused by Citrus bark cracking viroid (CBCVd) poses a major threat to the production of Humulus lupulus (hop) plants. In this study, we systematically investigate the characteristics of the lncRNAs in hop and their role in CBCVd-infection using RNA-sequencing data. Following a stringent filtration criterion, a total of 3598 putative lncRNAs were identified with a high degree of certainty, of which 19% (684) of the lncRNAs were significantly differentially expressed (DE) in CBCVd-infected hop, which were predicted to be mainly involved in plant-pathogen interactions, kinase cascades, secondary metabolism and phytohormone signal transduction. Besides, several lncRNAs and CBCVd-responsive lncRNAs were identified as the precursor of microRNAs and predicted as endogenous target mimics (eTMs) for hop microRNAs involved in CBCVd-infection.

Synthesis of pyranochalcone derivatives and their inhibitory effect on NF-κB activation

In an effort to identify novel inhibitors of nuclear factor kappa B (NF-κB), twenty five pyranochalcone derivatives were synthesized and evaluated for their in vitro activities against TNF-α induced NF-κB inhibition in HEK293T cells. Among all of these derivatives, several displaying the same acrylate moiety on the B ring exhibited potent inhibition, with IC₅₀ values ranging from 0.29 to 10.46 μM. A functional study of the most potent of these compounds, designated 6b, revealed that it significantly suppressed the transcriptional expression of inflammatory factor IL-1β in lipopolysaccharide-induced RAW 264.7 macrophages, and also mildly inhibited CCL2, IL6 and TNF-α. In addition, compound 6b was found to inhibit IL-1β released in LPS-induced BMDM cells. This study demonstrates that the inhibitory effect of 6b on LPS-stimulated inflammatory mediator production in the mouse macrophage cell line RAW 264.7 correlates with the suppression of the NF-κB and MAPK signaling pathways.

A draft phased assembly of the diploid Cascade hop (Humulus lupulus) genome

Hop (Humulus lupulus L. var Lupulus) is a diploid, dioecious plant with a history of cultivation spanning more than one thousand years. Hop cones are valued for their use in brewing and contain compounds of therapeutic interest including xanthohumol. Efforts to determine how biochemical pathways responsible for desirable traits are regulated have been challenged by the large (2.8 Gb), repetitive, and heterozygous genome of hop. We present a draft haplotype-phased assembly of the Cascade cultivar genome. Our draft assembly and annotation of the Cascade genome is the most extensive representation of the hop genome to date. PacBio long-read sequences from hop were assembled with FALCON and partially phased with FALCON-Unzip. Comparative analysis of haplotype sequences provides insight into selective pressures that have driven evolution in hop. We discovered genes with greater sequence divergence enriched for stress-response, growth, and flowering functions in the draft phased assembly. With improved resolution of long terminal retrotransposons (LTRs) due to long-read sequencing, we found that hop is over 70% repetitive. We identified a homolog of cannabidiolic acid synthase (CBDAS) that is expressed in multiple tissues. The approaches we developed to analyze the draft phased assembly serve to deepen our understanding of the genomic landscape of hop and may have broader applicability to the study of other large, complex genomes.

Recent patents on therapeutic activities of xanthohumol: a prenylated chalconoid from hops (Humulus lupulus L.)

There is expanding proof that specific natural compounds found in plants have additional conventional medicinal properties. One such compound is xanthohumol (XN), which is being explored as an antimicrobial, anticarcinogenic, antidiabetic and anti-inflammatory agent - aside from its utilization in dealing with conditions like autism, bone and skin improvement and microbial infections, lipid-related illnesses, and so on. XN is reported to suppress the uncontrolled production of inflammatory mediators responsible for diseases including cardiovascular disease, neurodegeneration and tumors. Further, it is accounted to limit adipogenesis and control obesity by focusing on principal adipocyte marker proteins. It is most generally utilized in the brewing industry as an additive and flavoring agent to add bitterness and aroma to beer. Present investigation sum up the patents filed in most recent 2 years on development of different pharmaceutical mixes and strategies dependent on various therapeutic potentials of XN.

6-Prenylnaringenin from Hops Disrupts ERα-Mediated Downregulation of CYP1A1 to Facilitate Estrogen Detoxification

Botanical dietary supplements (BDS) containing hops are sold as women's health supplements due to the potent hop phytoestrogen, 8-prenylnaringenin (8-PN), and the cytoprotective chalcone, xanthohumol. Previous studies have shown a standardized hop extract to beneficially influence chemical estrogen carcinogenesis in vitro by fostering detoxified 2-hydroxylation over genotoxic 4-hydroxylation estrogen metabolism. In this study, hop extract and its bioactive compounds were investigated for its mechanism of action within the chemical estrogen carcinogenesis pathway, which is mainly mediated through the 4-hydroxylation pathway catalyzed by CYP1B1 that can form gentoxic quinones. Aryl hydrocarbon receptor (AhR) agonists induce CYP1A1 and CYP1B1, while estrogen receptor alpha (ERα) inhibits transcription of CYP1A1, the enzyme responsible for 2-hydroxylated estrogens and the estrogen detoxification pathway. An In-Cell Western MCF-7 cell assay revealed hop extract and 6-prenylnaringenin (6-PN) degraded ERα via an AhR-dependent mechanism. Reverse transcription PCR and xenobiotic response element luciferase assays showed hop extract and 6-PN-mediated activation of AhR and induction of CYP1A1. A reduction in estrogen-mediated DNA (cytosine-5)-methyltransferase 1 (DNMT1) downregulation of CYP1A1 accompanied this activity in a chromatin immunoprecipitation assay. Ultimately, hop extract and 6-PN induced preferential metabolism of estrogens to their detoxified form in vitro. These results suggest that the standardized hop extract and 6-PN activate AhR to attenuate epigenetic inhibition of CYP1A1 through degradation of ERα, ultimately increasing 2-hydroxylated estrogens. A new mechanism of action rationalizes the positive influence of hop BDS and 6-PN on oxidative estrogen metabolism in vitro and, thus, potentially on chemical estrogen carcinogenesis. The findings underscore the importance of elucidating various biological mechanisms of action and standardizing BDS to multiple phytoconstituents for optimal resilience promoting properties.

Hops compounds modulatory effects and 6-prenylnaringenin dual mode of action on GABAA receptors

Hops (Humulus lupulus L.), a major component of beer, contain potentially neuroactive compounds that made it useful in traditional medicine as a sleeping aid. The present study aims to investigate the individual components in hops acting as allosteric modulators in GABA_A receptors and bring further insight into the mode of action behind the sedative properties of hops. GABA-potentiating effects were measured using [³H]ethynylbicycloorthobenzoate (EBOB) radioligand binding assay in native GABA_A receptors. Flumazenil sensitivity of GABA-potentiating effects, [³H]Ro 15-4513, and [³H]flunitrazepam binding assays were used to examine the binding to the classical benzodiazepines site. Humulone (alpha acid) and 6-prenylnaringenin (prenylflavonoid) were the most potent compounds displaying a modulatory activity at low micromolar concentrations. Humulone and 6-prenylnaringenin potentiated GABA-induced displacement of [³H]EBOB binding in a concentration-dependent manner where the IC₅₀ values for this potentiation in native GABA_A receptors were 3.2 μM and 3.7 μM, respectively. Flumazenil had no significant effects on humulone- or 6-prenylnaringenin-induced displacement of [³H]EBOB binding. [³H]Ro 15-4513 and [³H]flunitrazepam displacements were only minor with humulone but surprisingly prominent with 6-prenylnaringenin despite its flumazenil-insensitive modulatory activity. Thus, we applied molecular docking methods to investigate putative binding sites and poses of 6-prenylnaringenin at the GABA_A receptor α1β2γ2 isoform. Radioligand binding and docking results suggest a dual mode of action by 6-prenylnaringenin on GABA_A receptors where it may act as a positive allosteric modulator at α+β- binding interface as well as a null modulator at the flumazenil-sensitive α+γ2- binding interface.

Formation of (2R)- and (2S)-8-Prenylnaringenin Glucuronides by Human UDP-Glucuronosyltransferases

Occurring in hops (Humulus lupulus) and beer as a racemic mixture, (2R,2S)-8-prenylnaringenin (8-PN) is a potent phytoestrogen in hop dietary supplements used by women as alternatives to conventional hormone therapy. With a half-life exceeding 20 h, 8-PN is excreted primarily as 8-PN-7-O-glucuronide or 8-PN-4'-O-glucuronide. Human liver microsomes and 11 recombinant human UDP-glucuronosyltransferases (UGTs) were used to catalyze the formation of the two oxygen-linked glucuronides of purified (2R)-8-PN and (2S)-8-PN, which were subsequently identified using mass spectrometry and nuclear magnetic resonance spectroscopy. Formation of (2R)- and (2S)-8-PN-7-O-glucuronides predominated over the 8-PN-4'-O-glucuronides except for intestinal UGT1A10, which formed more (2S)-8-PN-4'-O-glucuronide. (2R)-8-PN was a better substrate for all 11 UGTs except for UGT1A1, which formed more of both (2S)-8-PN glucuronides than (2R)-8-PN glucuronides. Although several UGTs conjugated both enantiomers of 8-PN, some conjugated just one enantiomer, suggesting that human phenotypic variation might affect the routes of metabolism of this chiral estrogenic constituent of hops.

Dose-Dependent Alterations to In Vitro Human Microbiota Composition and Butyrate Inhibition by a Supercritical Carbon Dioxide Hops Extract

Hop cones (Humulus lupulus L.) have been used throughout history as an additive in beer brewing and as herbal supplements with medicinal and culinary properties. The objective of this study was to ascertain the effect of a range of concentrations of a supercritical CO2 extract of hops on the composition and metabolism of human gut bacterial communities using in vitro batch culture systems. Fermentations were conducted over 24 h using a mixed human fecal inoculum. Microbial metabolism was assessed by measuring organic acid production and microbial community alterations were determined by 16S rRNA gene sequencing. Butyrate, an important short chain fatty acid in maintaining colonic well-being, decreased at elevated concentrations of hops, which may partly be accounted for by the concomitant reduction of Eubacterium and Coprococcus, known butyrate-producing genera, and also the inhibition of Bifidobacterium, a beneficial organism that has a butyrogenic effect through metabolic cross-feeding with intestinal commensals. The hops compounds also caused dose-dependent increases in the potentially pathogenic Enterobacteriaceae and potentially beneficial Akkermansia. Thus, hops compounds had a significant impact on the structure of the bacterial consortium, which warrants further study including human clinical trials.

Do recent research studies validate the medicinal plants used in British Columbia, Canada for pet diseases and wild animals taken into temporary care?

ETHNOPHARMACOLOGICAL RELEVANCE

There are insufficient safe and effective treatments for chronic pain in pets. In cases such as osteoarthritis there is no commercially available cure and veterinarians use NSAIDs to manage pain. Pet owners may have to plan for a lifetime of plant-based treatment for the conditions that lead to chronic pain in pets. Phytopharmacotherapies have the advantage of being less toxic, cheap or free, readily available, are more likely to be safe for long-term use and have the potential to reset the immune system to normal functioning.

AIM OF THE STUDY

To examine the recently published medicinal plant research that matches unpublished data on ethnoveterinary medicines (EVM) used for pets in Canada (British Columbia) to see if the EVM data can provide a lead to the development of necessary drugs.

MATERIALS AND METHODS

In 2003 semi-structured interviews were conducted with 60 participants who were organic farmers or holisitic medicinal/veterinary practitioners obtained using a purposive sample. A draft manual prepared from the data was then evaluated by participants at a participatory workshop that discussed the plant-based treatments. A copy of the final version of the manual was given to all research participants. In 2018, the recently published research matching the EVM data was reviewed to see if the EVM practices could serve as a lead for further research.

RESULTS AND CONCLUSION

Medicinal plants are used to treat a range of conditions. The injuries treated in pets in British Columbia included abscesses (resulting from an initial injury), sprains and abrasions. Dogs were also treated with medicinal plants for rheumatoid arthritis, joint pain and articular cartilage injuries. More than 40 plants were used. Anal gland problems were treated with Allium sativum L., Aloe vera L., Calendula officinalis L., Plantago major L., Ulmus fulva Michx., Urtica dioica L. and Usnea longissima Ach. Arctium lappa, Hydrangea arborescens and Lactuca muralis were used for rheumatoid arthritis and joint pain in pets. Asthma was treated with: Linum usitatissimum L., Borago officinalis L., Verbascum thapsus L., Cucurbita pepo L., Lobelia inflata L., and Zingiber officinale Roscoe. Pets with heart problems were treated with Crataegus oxyacantha L., Cedronella canariensis (L.) Willd. ex Webb & Berth, Equisetum palustre L., Cypripedium calceolus L., Pinus ponderosa Douglas ex Lawson, Humulus lupulus L., Valeriana officinalis L., Lobelia inflata L., Stachys officinalis (L.) Trev., and Viscum album L. The following plants were used for epilepsy, motion sickness and anxiety- Avena sativa L., Valeriana officinalis, Lactuca muralis (L.) Fresen., Scutellaria lateriflora L., Satureja hortensis L., and Passiflora incarnata L. Plants used for cancer treatment included Phytolacca decandra, Ganoderma lucidum, Lentinula edodes, Rumex acetosella, Arctium lappa, Ulmus fulva, Rheum palmatum, Frangula purshiana, Zingiber officinale, Glycyrrhiza glabra, Ulmus fulva, Althea officinalis, Rheum palmatum, Rumex crispus and Plantago psyllium. Trifolium pratense was used for tumours in the prostate gland. Also used were Artemisia annua, Taraxacum officinale and Rumex crispus. This review of plants used in EVM was possible because phytotherapy research of the plants described in this paper has continued because few new pharmaceutical drugs have been developed for chronic pain and because treatments like glucocorticoid therapy do not heal. Phytotherapuetic products are also being investigated to address the overuse of antibiotics. There have also been recent studies conducted on plant-based functional foods and health supplements for pets, however there are still gaps in the knowledge base for the plants Stillingia sylvatica, Verbascum thapsus, Yucca schidigera and Iris versicolor and these need further investigation.

Impact of Hydroalcoholic Extract of Humulus Lupulus L. on Sperm Quality, Reproductive Organs and Hormones in Male Rats

OBJECTIVE

To investigate the impact of Humulus Lupulus L. hydroalcoholic extract on the body weights, reproductive organs, sperm quality and hormone levels in male rats.

METHODS

By simple random sampling method, seventy male Sprague-Dawley rats were randomly assigned to 7 groups including control group [distilled water, 1 mL/(kg•d)], Tween 80 group [25% Tween 80 solution, 1 mL/(kg•d)], olive oil group [olive oil, 1 mL/(kg•d)], diethyl stilbestrol (DES) group [DES, 100 μg/(kg•body weight)], H50, H150 and H450 [50, 150 and 400 mg/(kg•d) of Humulus Lupulus L extract, respectively]. The administration was performed via gavage once daily for 7 weeks. Body and reproductive organs weights including testes, seminal vesicles, epididymis and prostate were weighted and epididymal sperm quality were determined by digital balance. Blood samples were collected and serum free testosterone (T), luteinizing hormone (LH), follicle-stimulating hormone (FSH), and estrogen (E2) levels were measured by rat specific enzyme-linked immunosorbent assay.

RESULTS

The percentage increase in mean body weights of rats in the DES and H50, H150 and H450 groups decreased significantly compared to olive oil and Tween 80 groups (all P<0.05). The weights of seminal vesicle, epididymis and testes in rats receiving H50 were significantly higher than the control group (P<0.05 or P<0.01). The sperm count in the rats receiving H50 was significantly lower than the control group (P<0.05). The sperm motile characteristics of the rats receiving hydroalcoholic extract at and DES were significantly lower than those of the control or rats receiving vehicles (all P<0.05). In H50, H150, H450 and DES groups, T and LH levels were decreased, and E2 was significantly increased compared to the control (P<0.05 or P<0.01). The FSH level did not change in all groups (P>0.05).

CONCLUSION

Humulus Lupulus L. extract significantly increased the seminal vesicle and testes weights and reduced the sperm motility.

The Multiple Biological Targets of Hops and Bioactive Compounds

Botanical dietary supplements for women's health are increasingly popular. Older women tend to take botanical supplements such as hops as natural alternatives to traditional hormone therapy to relieve menopausal symptoms. Especially extracts from spent hops, the plant material remaining after beer brewing, are enriched in bioactive prenylated flavonoids that correlate with the health benefits of the plant. The chalcone xanthohumol (XH) is the major prenylated flavonoid in spent hops. Other less abundant but important bioactive prenylated flavonoids are isoxanthohumol (IX), 8-prenylnaringenin (8-PN), and 6-prenylnaringenin (6-PN). Pharmacokinetic studies revealed that these flavonoids are conjugated rapidly with glucuronic acid. XH also undergoes phase I metabolism in vivo to form IX, 8-PN, and 6-PN. Several hop constituents are responsible for distinct effects linked to multiple biological targets, including hormonal, metabolic, inflammatory, and epigenetic pathways. 8-PN is one of the most potent phytoestrogens and is responsible for hops' estrogenic activities. Hops also inhibit aromatase activity, which is linked to 8-PN. The weak electrophile, XH, can activate the Keap1-Nrf2 pathway and turn on the synthesis of detoxification enzymes such as NAD(P)H-quinone oxidoreductase 1 and glutathione S-transferase. XH also alkylates IKK and NF-κB, resulting in anti-inflammatory activity. Antiobesity activities have been described for XH and XH-rich hop extracts likely through activation of AMP-activated protein kinase signaling pathways. Hop extracts modulate the estrogen chemical carcinogenesis pathway by enhancing P450 1A1 detoxification. The mechanism appears to involve activation of the aryl hydrocarbon receptor (AhR) by the AhR agonist, 6-PN, leading to degradation of the estrogen receptor. Finally, prenylated phenols from hops are known inhibitors of P450 1A1/2; P450 1B1; and P450 2C8, 2C9, and 2C19. Understanding the biological targets of hop dietary supplements and their phytoconstituents will ultimately lead to standardized botanical products with higher efficacy, safety, and chemopreventive properties.

Hop Compounds: Extraction Techniques, Chemical Analyses, Antioxidative, Antimicrobial, and Anticarcinogenic Effects

Hop plants comprise a variety of natural compounds greatly differing in their structure and properties. A wide range of methods have been developed for their isolation and chemical analysis, as well as for determining their antioxidative, antimicrobial, and antigenotoxic potentials. This contribution provides an overview of extraction and fractionation techniques of the most important hop compounds known for their health-promoting features. Although hops remain the principal ingredient for providing the taste, stability, and antimicrobial protection of beer, they have found applications in the pharmaceutical and other food industries as well. This review focuses on numerous health-promoting effects of hops raging from antioxidative, sedative, and anti-inflammatory potentials, over anticarcinogenic features to estrogenic activity. Therefore, hops should be exploited for the prevention and even healing of several prevalent diseases like cardiovascular disorders and various cancer types. New ideas for future studies on hops are finally presented: computational investigations of chemical reactivities of hop compounds, nanoencapsulation, and synergistic effects leading to a higher bioavailability of biologically active substances as well as the application of waste hop biomass from breweries for the production of high-added-value products in accordance with the biorefinery concept.

Antimicrobial Properties of Spent Hops Extracts, Flavonoids Isolated Therefrom, and Their Derivatives

Hop cones preparations possess a wide range of biological activities including antimicrobial properties. In this work, we evaluated the effect of various organic extracts obtained from spent hops, as well as six hops flavonoids and their twenty natural and synthetic derivatives on human and plant microbial pathogens. Methylene chloride, acetone, ethyl acetate, and methanol were used as extractants. Seven flavonoids, among them two natural (α,β-dihydroxanthohumol and 8-prenylnaringenin) showed significant activity against methicillin sensitive and resistant Staphylococcus aureus and Staphylococcus epidermidis strains with the lowest MIC80 value of 0.5 µg/mL. The crude ethyl acetate, acetone, and methanol extracts from the spent hops exhibited antifungal activity against Fusarium oxysporum, F. culmorum, and F. semitectum with the lowest MIC50 of 0.5 mg/mL, while the methylene chloride extract exerted antifungal activity against Botrytis cinerea with the MIC50 of 1 mg/mL. The preparation obtained after the removal of xanthohumol from the spent hops crude extracts retained up to 95% of activity. These findings suggest that various spent hops extracts may be effective agents for the control of plant pathogens of economic importance, like Botrytis cinerea and Fusarium oxysporum, while some compounds from spent hops or their derivatives may become useful for staphylococcal infections.

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.

Sequential Elution of Essential Oil Constituents during Steam Distillation of Hops (Humulus lupulus L.) and Influence on Oil Yield and Antimicrobial Activity

The profile and bioactivity of hops (Humulus lupulus L.) essential oil, a complex natural product extracted from cones via steam distillation, depends on genetic and environmental factors, and may also depend on extraction process. We hypothesized that compound mixtures eluted sequentially and captured at different timeframes during the steam distillation process of whole hop cones would have differential chemical and bioactivity profiles. The essential oil was collected sequentially at 8 distillation time (DT) intervals: 0-2, 2-5, 5-10, 10-30, 30-60, 60-120, 120-180, and 180-240 min. The control was a 4-h non-interrupted distillation. Nonlinear regression models described the DT and essential oil compounds relationship. Fractions yielded 0.035 to 0.313% essential oil, while control yielded 1.47%. The oil eluted during the first hour was 83.2%, 9.6% during the second hour, and only 7.2% during the second half of the distillation. Essential oil (EO) fractions had different chemical profile. Monoterpenes were eluted early, while sequiterpenes were eluted late. Myrcene and linalool were the highest in 0-2 min fraction, β-caryophyllene, β-copaene, β-farnesene, and α-humulene were highest in fractions from middle of distillation, whereas α- bergamotene, γ-muurolene, β- and α-selinene, γ- and δ-cadinene, caryophyllene oxide, humulne epoxide II, τ-cadinol, and 6-pentadecen-2-one were highest in 120-180 or 180-240 min fractions. The Gram-negative Escherichia coli was strongly inhibited by essential oil fractions from 2-5 min and 10-30 min, followed by oil fraction from 0-2 min. The strongest inhibition activity against Gram-negative Yersinia enterocolitica, and Gram-positive Clostridium perfringens, Enterococcus faecalis, and Staphylococcus aureus subs. aureus was observed with the control essential oil. This is the first study to describe significant activity of hops essential oils against Trypanosoma brucei, a parasitic protozoan that causes African trypanosomiasis (sleeping sickness in humans and nagana in other animals). Hops essential oil fractions or whole oil may be used as antimicrobial agents or for the development of new drugs.

Synthesis and Antiproliferative Activity of Minor Hops Prenylflavonoids and New Insights on Prenyl Group Cyclization

Synthesis of minor prenylflavonoids found in hops and their non-natural derivatives were performed. The antiproliferative activity of the obtained compounds against some human cancer cell lines was investigated. Using xanthohumol isolated from spent hops as a lead compound, a series of minor hop prenylflavonoids and synthetic derivatives were obtained by isomerization, cyclisation, oxidative-cyclisation, oxidation, reduction and demethylation reactions. Three human cancer cell lines-breast (MCF-7), prostate (PC-3) and colon (HT-29)-were used in antiproliferative assays, with cisplatin as a control compound. Five minor hop prenyl flavonoids and nine non-natural derivatives of xanthohumol have been synthetized. Syntheses of xanthohumol K, its dihydro- and tetrahydro-derivatives and 1″,2″,α,β-tetrahydroxanthohumol C were described for the first time. All of the minor hops prenyl flavonoids exhibited strong to moderate antiproliferative activity in vitro. The minor hops flavonoids xanthohumol C and 1″,2″-dihydroxanthohumol K and non-natural 2,3-dehydroisoxanthohumol exhibited the activity comparable to cisplatin. Results described in the article suggest that flavonoids containing chromane- and chromene-like moieties, especially chalcones, are potent antiproliferative agents. The developed new efficient, regioselective cyclisation reaction of the xanthohumol prenyl group to 1″,2″-dihydroxantohumol K may be used in the synthesis of other compounds with the chromane moiety.

Therapeutic Perspectives of 8-Prenylnaringenin, a Potent Phytoestrogen from Hops

Hop (Humulus lupulus L.), as a key ingredient for beer brewing, is also a source of many biologically active molecules. A notable compound, 8-prenylnaringenin (8-PN), structurally belonging to the group of prenylated flavonoids, was shown to be a potent phytoestrogen, and thus, became the topic of active research. Here, we overview the pharmacological properties of 8-PN and its therapeutic opportunities. Due to its estrogenic effects, administration of 8-PN represents a novel therapeutic approach to the treatment of menopausal and post-menopausal symptoms that occur as a consequence of a progressive decline in hormone levels in women. Application of 8-PN in the treatment of menopause has been clinically examined with promising results. Other activities that have already been assessed include the potential to prevent bone-resorption or inhibition of tumor growth. On the other hand, the use of phytoestrogens is frequently questioned regarding possible adverse effects associated with long-term consumption. In conclusion, we emphasize the implications of using 8-PN in future treatments of menopausal and post-menopausal symptoms, including the need for precise evidence and further investigations to define the safety risks related to its therapeutic use.

Effect of hop (Humulus lupulus L.) inclusion in the diet for fattening lambs on animal performance, ruminal characteristics and meat quality

Thirty male merino lambs were fed with a pelleted total mixed ration (TMR) alone or supplemented with hop (Humulus lupulus L.) cones at two different doses (1.5 and 3.0 g hop cones/kg pelleted TMR, respectively), to study the effects of this dietary source of antioxidants on animal performance, ruminal parameters and meat quality attributes. The results showed that dietary supplementation with hop cones decreased lambs' growth rate (P < 0.05) due to a shift in ruminal fermentation, towards a more acetic and less propionic acid production (P < 0.05). These changes in animal growth rate might have promoted microstructural modifications in the quantity and size of muscle fibres, thereby inducing the differences observed in meat chemical composition, colour and texture (P < 0.05), regardless of the lack of differences in meat antioxidant status (P > 0.10).

8-Prenylnaringenin from hop (Humulus lupulus L.) – a panacea for menopause?

8-Prenylnaryngenin (8-PN) is the strongest known phytoestrogen (PE). Its main source is the female inflorescences of hops (Humulus lupulus L.). 8-PN, which, in contrast to other PEs, is proven to have stronger activity and higher affinity for the α subtype of estrogen receptor (ER). Therefore, it may be an effective substitute for hormone replacement therapy (HRT). The studies in postmenopausal women have shown its particular effectiveness in reducing hot flashes. However, a strong stimulation of uterus by 8-PN may be associated with the occurrence of adverse effects (eg. bleeding) and increase the risk of carcinogenesis. The H. lupulus extracts preparations are currently supplements which makes control of the doses used and thus increases the occurrence of uncontrolled self-treatment difficult. This paper presents the current knowledge on 8-PN and discusses the potential risks associated with use of hops to alleviate the symptoms of menopause.

Estrogenic Potentials of Traditional Chinese Medicine

Estrogen, a steroid hormone, is associated with several human activities, including environmental, industrial, agricultural, pharmaceutical and medical fields. In this review paper, estrogenic activity associated with traditional Chinese medicines (TCMs) is discussed first by focusing on the assays needed to detect estrogenic activity (animal test, cell assay, ligand-binding assay, protein assay, reporter-gene assay, transcription assay and yeast two-hybrid assay), and then, their sources, the nature of activities (estrogenic or anti-estrogenic, or other types), and pathways/functions, along with the assay used to detect the activity, which is followed by a summary of effective chemicals found in or associated with TCM. Applications of estrogens in TCM are then discussed by a comprehensive search of the literature, which include basic study/pathway analysis, cell functions, diseases/symptoms and medicine/supplements. Discrepancies and conflicting cases about estrogenicity of TCM among assays or between TCM and their effective chemicals, are focused on to enlarge estrogenic potentials of TCM by referring to omic knowledge such as transcriptome, proteome, glycome, chemome, cellome, ligandome, interactome and effectome.

Deterrent activity of hops flavonoids and their derivatives against stored product pests

Five flavonoids from hops, two of their derivatives, along with naringenin used as a model compound, were tested for their antifeedant activity against three coleopteran stored product pests: Sitophilus granarius L., Tribolium confusum Duv. and Trogoderma granarium Everts. The introduction, into the tested flavonoid molecules, of additional structural fragments such as prenyl or dimethylpyran moiety, is proposed to significantly alter the deterrent activity of the compounds. The prenyl moiety in flavonoids increased the deterrent activity of these compounds in all three of the grain feeding species used in the tests. It is also concluded that the introduction of dimethylpyran moiety to the flavonoid structure increases its deterrent activity in S. granarius and T. confusum, but in one of the test insects, T. granarium, an increased feeding was observed in response to the introduction of dimethylpyran moiety to the flavonoid structure.

DESIGNER Extracts as Tools to Balance Estrogenic and Chemopreventive Activities of Botanicals for Women's Health

Botanical dietary supplements contain multiple bioactive compounds that target numerous biological pathways. The lack of uniform standardization requirements is one reason that inconsistent clinical effects are reported frequently. The multifaceted biological interactions of active principles can be disentangled by a coupled pharmacological/phytochemical approach using specialized ("knock-out") extracts. This is demonstrated for hops, a botanical for menopausal symptom management. Employing targeted, adsorbent-free countercurrent separation, Humulus lupulus extracts were designed for pre- and postmenopausal women by containing various amounts of the phytoestrogen 8-prenylnaringenin (8-PN) and the chemopreventive constituent xanthohumol (XH). Analysis of their estrogenic (alkaline phosphatase), chemopreventive (NAD(P)H-quinone oxidoreductase 1 [NQO1]), and cytotoxic bioactivities revealed that the estrogenicity of hops is a function of 8-PN, whereas their NQO1 induction and cytotoxic properties depend on XH levels. Antagonization of the estrogenicity of 8-PN by elevated XH concentrations provided evidence for the interdependence of the biological effects. A designed postmenopausal hop extract was prepared to balance 8-PN and XH levels for both estrogenic and chemopreventive properties. An extract designed for premenopausal women contains reduced 8-PN levels and high XH concentrations to minimize estrogenic while retaining chemopreventive properties. This study demonstrates the feasibility of modulating the concentrations of bioactive compounds in botanical extracts for potentially improved efficacy and safety.

Insecticidal effects of extracts of Humulus lupulus (hops) L. cones and its principal component, xanthohumol

Insecticidal effects of the dichloromethane, ethyl acetate, acetone, ethanol and methanol extracts of Humulus lupulus (hops) L. cones and its principal components, xanthohumol was investigated on five stored pests, Sitophilus granarius (L.), Sitophilus oryzae (L.), Acanthoscelides obtectus (Say.), Tribolium castaneum (Herbst) and Lasioderma serricorne (F.). The mortality of adults of the insects treated with 2, 5, 5, 10 and 20 mg ml̠-1 concentrations of the extracts and xanthuhumol was counted after 24, 48, 72, 96 and 120 h. In order to determine the toxic effects of the substances tested against all tested insects, durations for 50% mortality of the adults, and LD50 values were also determined in the first 48 h by probit analysis. Our results also showed that xanthohumol was more toxic against the pests in comparison with the extracts applications. LD50 values for xanthohumol were found to be low dose as compared with the extracts. Xanthohumol was more toxic against S. granarius (L.) with 6.8 µg of LD50 value. Among the extracts, methanol extract was less effective than other extracts against all tested insects. The ethyl acetate extract of H. lupulus cones was the most effective extract against the tested pests. The quantitative amounts of xanthohumol in the extracts were determined using a high-performance liquid chromatography. The quantitative data indicated that amount of xanthohumol in the extracts increased with increase of polarity of the solvents used from methanol to dichloromethane. The methanol extract contained the high amount of xanthohumol with 5.74 g/100 g extract (0.46 g/100 g plant sample).