In vitro effects and mechanisms of Humulus lupulus extract on bone marrow progenitor cells and endothelial cells.

Osteoporosis is the most common metabolic bone disorder and is associated with a high incidence of fractures. Angiogenesis and adequate blood flow are important during bone repair and maintenance. Estrogens play a key role in bone formation, in the prevention of bone resorption and vasculature maintenance. Hormone replacement therapy (HRT) has been used with great benefits for bone fracture prevention but has been linked to the development of serious important side effects, including cancer and stroke. Phytoestrogens are an attractive alternative to HRT because their chemical structure is similar to estradiol but, they could behave as selective modulators: acting as antagonists of estrogen receptors in the breast and endometrium and as agonists in the vascular endothelium and bone. Hops contain a wide variety of phytoestrogens that have individually been shown to possess estrogenic activity by either blocking or mimicking. In this study we have to evaluate the in vitro effects and mechanisms of action of hops extracts on the osteogenic and adipogenic capacity of bone marrow progenitor cells (BMPCs), and the angiogenic potential of EA.hy926 endothelial cells. We show that hops extracts increase the proliferative capacity of BMPCs and promote their osteogenic differentiation while decreasing their pro-osteoclastogenic capacity; and that these effects are mediated by the MAPK pathway. Additionally, hops extracts prevent the adipogenic differentiation of BMPCs and promote endothelial cell activity, by mechanisms also partially mediated by MAPK.

Hop (Humulus lupulus L.) extract reverts glycaemic imbalance and cognitive impairment in an animal model of obesity.

The rates of overweight and obesity around the world have increased in past years. The body's adipose tissue stimulates the antioxidant and oxidation imbalance capacity at the cellular level. This scenario favors an inflammatory low-grade systemic condition starting with insulin resistance, which in turn may involve diabetes mellitus type 2 and cognitive decline afterward. Neurological diseases have been correlated to senile age diseases over time. This scenario calls for a change in the incidence of obesity in the younger generation. An unhealthy dietary consumption together with sedentary habits might lead to poor gut absorption of nutrients. Several plants and foods have bioactive compounds that can reduce or inhibit radical scavengers, reactive oxygen species, and metal ion complexes that threaten the cerebral defense system. The bitter acids from hops (Humulus lupulus L.) have been demonstrated to have promising effects on lipid and carbohydrate metabolism improvement, reducing inflammatory responses through alpha acids, beta acids, and analogs action. Therefore, the current study aimed to investigate the bioactivity of hop bitter acids in obese and lean mice. For that, a dry hop extract (DHE) was obtained by applying carbon dioxide as the fluid of supercritical extraction. Afterward, seventy-eight male mice of the C57BL/6J strain were weighed and randomly distributed into six groups of 13 animals each according to the diet offered: (NO) normolipidic diet, (NO1) normolipidic diet containing 0.35% alpha acids, (NO2) normolipidic diet containing 3.5% alpha acids, (HP) hyperlipidic diet, (HP1) hyperlipidic diet containing 0.35% alpha acids, and (HP2) hyperlipidic diet containing 3.5% alpha acids. After applying the glycemic tolerance and insulin tolerance tests, a better stabilization of glycemia levels and weight gain among those animals fed with DHE (NO2 and HP2) were observed in comparison to the obese control group (HP) (p < 0.05). There was also an amelioration of antioxidant capacity observed by checking the enzymatic profile by SOD and an apparent mitigation of brain degeneration by checking GSK3ß and p-IRS1 proteins expression (p < 0.05). The y-maze cognitive test applied to highlight possible obesity-harmful animal brains did not indicate a statistical difference between the groups. Although the weekly dietary intake between the obese HP2 group (33.32 ± 4.11, p < 0.05) and control HP (42.3 ± 5.88, p < 0.05) was different. The bioactive compounds present in DHE have demonstrated relevant effects on glycemic control, insulin signaling, and the consequent modulatory action of the obesity-related markers with the brain's inflammatory progression.

Comparison of α and ß-acid isomerization in hops and beer using HPLC, confocal microscopy, spectrofluorimetry and chemical analysis of metabolites and essential oils in flowers of different hop cultivars produced in Brazil.

We used confocal microscopy and spectrofluorescence to characterize the emission spectra in hop flowers, to follow the isomerization processes in different hop preparations, and beers, to compare with HPLC extracted samples. Flowers of different hop cultivars produced in three regions of Brazil, were quantitated by HPLC and GC-MS. The fluorescence spectra showed two characteristic emission bands evaluated from different preparations. The isomerization process leads to a gradual decrease in fluorescence intensity as the reaction progresses. This demonstrates the valuable use of confocal microscopy and fluorescence spectroscopy for analysis of the correlation between bitter acid indices with fluorescence intensity and lifetime microscopy. Such techniques can be used directly in the flowers allowing rapid monitoring of the brewing process. Twenty-nine substances were characterized in the essential oils and some cultivars presented quantities of bitter acids and essential oil levels close to those expected for plants after more than three years of cultivation.

Unlocking hot trub's potential: a simple method for extracting bitter acids and xanthohumol.

BACKGROUND: Hot trub is a macronutrient- and micronutrient-rich by-product generated in the brewing industry, which is still underrated as a raw material for reprocessing purposes. In this context, this study aimed to investigate the extraction of bitter acids' and xanthohumol from hot trub as well as identify the significance of parameters for the process. The research assessed various extraction parameters, such as pH, ethanol concentration, temperature, and solid-to-liquid ratio, using a Plackett-Burman design. RESULTS: Ethanol concentration and pH were the most significant parameters affecting extraction yield. ß-acids were found to be the principal components of the bitter acids, with a maximum concentration near 16 mg g-1, followed by iso-α-acids and α-acids achieving 6 and 3.6 mg g-1, respectively. The highest yields of bitter acids were observed in the highest ethanol concentration, while pH was relevant to extraction process in treatments with low ethanol ratios. Concerning the xanthohumol extraction, the approach achieved maximum concentration (239 µg g-1) in treatments with ethanol concentration above 30%. Despite their variances, the phytochemicals exhibited comparable extraction patterns, indicating similar interactions with macromolecules. Moreover, the characterization of the solid residues demonstrated that the extraction process did not bring about any alterations to the chemical and total protein profiles. CONCLUSION: Ethanol concentration was found to have the most significant impact on the extraction of bitter acids and xanthohumol, while temperature had no significant effect. The solid remains resulting from the extraction showed potential for use as a protein source. © 2024 Society of Chemical Industry.

Extraction of hops pelletized (Humulus lupulus) with subcritical CO2 and hydrodistillation: Chemical composition identification, kinetic model, and evaluation of antioxidant and antimicrobial activity.

Hop essential oil and hop extract using carbon dioxide (CO2) are products with high added value because they have bioactive and sensory properties. In this context, the objective of this study was to obtain and characterize essential oil and extracts from pelleted hops of El Dorado, Polaris, Hallertau Blanc and Callista varieties using hydrodistillation and subcritical CO2 extraction methods. Extraction yield ranged from 0.38 % to 1.97 % (m/m) for essential oils and from 8.76 % to 15.35 % (m/m) for extracts using subcritical CO2. The chemical compositions of the essential oils were mainly monoterpene (18.14 % to 29.91 %) and sesquiterpene (46.01 % to 59.03 %) hydrocarbons and for the extracts were sesquiterpene hydrocarbons (33.05 % to 71.90 %) and oxygenated sesquiterpenes (14.80 % to 34.89 %). The extracts showed better antioxidant activity than essential oils due to the presence of phenolic compounds and flavonoids. Hop extracts showed some antimicrobial activity, but essential oils did not demonstrate antimicrobial potential. Hop extracts obtained with subCO2 have the potential to be used in the brewing industry as a flavoring and as natural antioxidants.

Análise da relação entre a caracterização química de cervejas e o conteúdo de alfa ácidos presente em dois cultivares de lúpulo / Analysis to study the relationship between the chemical characterization of beers and the content of alpha acids present in two cultivars of hops

O lúpulo (Humulus lupulusL.) é uma planta cuja inflorescência feminina é utilizada na indústria cervejeira para conferir amargor e aroma à bebida, sendo que, o Brasil importa cerca de 98% desta matéria-prima. Entretanto, essa planta vem ganhando destaque no país, influenciando diretamente as características de qualidade do produto final. Desta forma, o objetivo deste estudo foi explorar a relação entre o teor de alfa ácidos de dois cultivares de lúpulo produzidos no Brasil e nos Estados Unidos (primeiro no ranking em produção da cultura). O trabalho foi desenvolvido na Universidade de Estado de Santa Catarina ­Centro de Ciências Agroveterinárias (UDESC/CAV), em Lages/SC, no ano de 2021. Uma cerveja padrão do estilo Indian Pale Ale (IPA), com a mesmareceita base, foi produzida. Cada tratamento consistiu na adição de diferentes cultivares de lúpulo (Comet e Fuggle) de duas origens (Brasil e Estados Unidos). Os resultados confirmaram que os cultivares e a origem do lúpulo influenciam as característicasquímicas das cervejas avaliadas. A quantidade de compostos fenólicos totais, flavonoides e atividade antioxidante da cerveja produzida como cultivar Fuggle brasileiro foi 6,5% (850,09 meq ácido gálico L-1); 75,5% (95,07 meq quercetina L-1) e 13,8% (6890 mmol Trolox L-1) superior, respectivamente, em relação à cerveja produzida com o mesmo cultivar originário dos Estados Unidos. Houve uma correlação negativa entre o teor de alfa ácidos e o conteúdo fenólico e capacidade antioxidante das cervejas. As cervejas em que foi utilizado lúpulo Fugglebrasileiro, com o menor teor de alfa ácidos dentre os avaliados, apresentaram maior associação positiva com o conteúdo de polifenóis totais, individuais e capacidade antioxidante das cervejas. Assim, as cervejas produzidas com o cultivar FuggleBrasileiro apresentaram maior acúmulo de substâncias antioxidantes relacionadas com os indicadores de qualidade para o processamento e conservação da bebida.(AU)

Hops (Humulus lupulusL.) is a plant whose female inflorescence is used in the brewing industry to impart bitterness and aroma to the drink, and Brazil imports about 98% of this raw material. However, this plant has been gaining prominence in the country, directly influencing the quality characteristics of the final product. Thus, the aim of this study was to explore the relationship between the alpha acids content of two hop cultivars produced in Brazil and the United States. The work was developed at UDESC/CAV, in Lages/SC, in the year 2021. A standard Indian Pale Ale beer, with the same base recipe, was produced. Each treatment consisted of the addition of different hop cultivars (Comet and Fuggle) from two origins (Brazilian and American). The results confirm that the cultivars and the origin of the hops influence the chemical characteristics of the evaluatedbeers. The amount of total phenolic compounds, flavonoids and antioxidant activity of the beer produced with the Brazilian Fuggle cultivar was 6.5% (850.09 meq gallic acid L-1); 75.5% (95.07 meq quercetin L-1) and 13.8% (6890 mmol Trolox L-1) higher, respectively, in relation to beer produced with the same cultivar originating in the United States. There was an inverse correlation between the alpha acid content and the phenolic content and antioxidant capacity of the beers. The beers in which Brazilian Fuggle hops were used, with the lowest alpha acid content among those adopted, showed a greater positive association with the total polyphenol content, individuals and antioxidant capacity of the beers. In conclusion, the beers produced with the cultivar Fuggle Brasileiro have a greater concentration of antioxidant substances.(AU)

Redox and Anti-Inflammatory Properties from Hop Components in Beer-Related to Neuroprotection.

Beer is a fermented beverage widely consumed worldwide with high nutritional and biological value due to its bioactive components. It has been described that both alcoholic and non-alcoholic beer have several nutrients derived from their ingredients including vitamins, minerals, proteins, carbohydrates, and antioxidants that make beer a potential functional supplement. Some of these compounds possess redox, anti-inflammatory and anticarcinogenic properties making the benefits of moderate beer consumption an attractive way to improve human health. Specifically, the hop cones used for beer brewing provide essential oils, bitter acids and flavonoids that are potent antioxidants and immune response modulators. This review focuses on the redox and anti-inflammatory properties of hop derivatives and summarizes the current knowledge of their neuroprotective effects.

Crystal structure and physicochemical characterization of a phytocystatin from Humulus lupulus: Insights into its domain-swapped dimer.

Phytocystatins are a family of plant cysteine-protease inhibitors of great interest due to their biotechnological application in culture improvement. It was shown that their expression in plants increases resistance to herbivory by insects and improves tolerance to both biotic and abiotic stress factors. In this work, owing to the economical relevance of the source organism, a phytocystatin from hop (Humulus lupulus), Hop1, was produced by heterologous expression in E. coli Lemo21 (DE3) cultivated in auto-inducing ZYM-5052 medium and purified by immobilized metal ion affinity and size exclusion chromatography. Thermal denaturation assays by circular dichroism showed that Hop1 exhibited high melting temperatures ranging from 82 °C to 85 °C and high thermal stability at a wide pH range, with ΔG25's higher than 12 kcal/mol. At 20 °C and pH 7.6, the dimeric conformation of the protein is favored according to size exclusion chromatography and analytical ultracentrifugation data, although monomers and higher order oligomers could still be detected in a lesser extent. The crystal structure of Hop1 was solved in the space groups P 2 21 21 and C 2 2 21 at resolutions of 1.80 Å and 1.68 Å, respectively. In both models, Hop1 is folded as a domain-swapped dimer where the first inhibitory loop undergoes a significant structural change and interacts with their equivalent from the other monomer forming a long antiparallel beta strand, leading to loss of inhibitory activity.

Combination of natural antimicrobials for contamination control in ethanol production.

Presence of bacterial contaminants at levels > 107 colony forming units per milliliter (CFU/mL) during ethanol production processes reduces the alcoholic fermentation yield by 30%. Antibiotics are currently used to control contamination, but their residues may be detected in yeast extract, restricting this by-product trade to several countries. Thus, the objective of this study was to assess antimicrobial activity of the natural compounds hops extract, 4-hydroxybenzoic acid, nisin Z, and lysozyme against Lactobacillus fermentum, Leuconostoc mesenteroides, and Saccharomyces cerevisiae, aiming development of a formula. Minimum Inhibitory Concentration of each antimicrobial was determined for bacteria and subsequently, nisin (30 mg/L) and hops extract (5 mg/L) were tested together, showing inhibitory effects combining doses of each antimicrobial that were equivalent to an eightfold reduction of their original Minimum Inhibitory Concentrations (3.75 and 0.625 mg/L, respectively), resulting in a FICIndex of 0.25. Thereon, a formula containing both compounds was developed and tested in fermentation assays, promoting reductions on bacterial population and no severe interferences in yeast viability or population even at extreme doses. Therefore, these compounds have great potential to successfully substitute conventional antibiotics in the ethanol industry.

Baseline separation of α and ß-acids homologues and isomers in hop (Humulus lupulus L.) by CD-MEKC-UV.

An alternative method for simultaneous baseline separation of α and ß-acids homologues and isomers in hop by CD-MEKC with UV detection was proposed. The optimized background electrolyte was composed of 30 mmol/L sodium tetraborate solution, 45 mmol/L sodium dodecyl sulfate, 20 mmol/L ß-cyclodextrin and 10% v/v acetonitrile. The instrumental conditions were evaluated by using a 33 Box-Benhken experimental design. In order to demonstrate the applicability of the method, 21 hop samples from different varieties were analyzed. The repeatability intra- and interday tests were performed and relative standard deviations lower than 7% for area and migration times were observed. The present method comprehended 8 min analysis time and revealed to be faster and more efficient when compared to previous reports from literature.

Phenolic Compounds from Humulus lupulus as Natural Antimicrobial Products: New Weapons in the Fight against Methicillin Resistant Staphylococcus aureus, Leishmania mexicana and Trypanosoma brucei Strains.

New anti-infective agents are urgently needed to fight microbial resistance. Methicillin-resistant Staphylococcus aureus (MRSA) strains are particularly responsible for complicated pathologies that are difficult to treat due to their virulence and the formation of persistent biofilms forming a complex protecting shell. Parasitic infections caused by Trypanosoma brucei and Leishmania mexicana are also of global concern, because of the mortality due to the low number of safe and effective treatments. Female inflorescences of hop produce specialized metabolites known for their antimicrobial effects but underexploited to fight against drug-resistant microorganisms. In this study, we assessed the antimicrobial potential of phenolic compounds against MRSA clinical isolates, T. brucei and L. mexicana. By fractionation process, we purified the major prenylated chalcones and acylphloroglucinols, which were quantified by UHPLC-UV in different plant parts, showing their higher content in the active flowers extract. Their potent antibacterial action (MIC < 1 µg/mL for the most active compound) was demonstrated against MRSA strains, through kill curves, post-antibiotic effects, anti-biofilm assays and synergy studies with antibiotics. An antiparasitic activity was also shown for some purified compounds, particularly on T. brucei (IC50 < 1 to 11 µg/mL). Their cytotoxic activity was assessed both on cancer and non-cancer human cell lines.

Capillary electrophoresis in association with chemometrics approach for bitterness hop (Humulus lupulus L.) classification.

The precursor compounds related to the bitterness of beer are called α-acids. These compounds are extracted from the hop, which is an important ingredient in the brewing process. These compounds were analyzed by capillary electrophoresis. The electrophoretic method used 160 mmol/L of ammonium carbonate (pH 9) as BGE (background electrolyte), a voltage of +20 kV in a capillary with 50 µm of internal diameter and with a 62.5 cm of total length (54 cm effective). The samples were injected in hydrodynamic mode applying a pressure of 25 mbar for 5 s and the analytes were detected at 230 nm. A hydromethanolic extraction during 3 h was considered as the optimum condition for the sample preparation using MeOH/H2 O 80:20 v/v as the extract solution. From the optimized conditions the electropherograms were evaluated for their use as input for chemometric modeling. Preprocessing investigation for electrophoretic data taking into account the alignment, denoising and baseline correction, and variable selection were considered before the chemometric modeling using principal component analysis (PCA). The electrophoretic data were systematically evaluated to find the optimum conditions to modeling. A PCA analysis for all tests was carried out using different preprocessing methods and, an explained variance higher than 90% was achieved in all of them. The optimized chemometric method worked with aligned and meancentered data. From this approach, a simple and efficient method to classify hop samples with high and low α-acids content without the use of analytical standards was established from a simple electrophoretic analysis.

Effects of dietary hop (Humulus lupulus L.) ß-acids on quality attributes, composition and oxidative stability of pork meat.

BACKGROUND: The effects of dietary levels of hop ß-acids on physical attributes, lipid oxidation and chemical composition of pork meat were evaluated. Thirty-two castrated male pigs obtained from a complete block design feeding experiment (6.23 ± 0.42 kg initial body weight (BW) to 20.45 ± 0.95 kg final BW) and fed diets supplemented with 0, 120, 240 or 360 mg kg-1 hop ß-acids during 35 days were slaughtered to sample longissimus dorsi muscle for meat analysis. RESULTS: No effects (P > 0.05) of dietary hop ß-acids were observed on meat physical attributes. Quadratic effects (P < 0.05) of hop ß-acids were observed on lipid and protein contents and on thiobarbituric acid-reactive substance (TBARS) values of meatballs, whose equations allowed the estimation of dietary hop ß-acid levels of 176, 169 and 181 mg kg-1 to provide up to 16.20% lipid reduction, 1.95% protein accretion and 23.31% TBARS reduction respectively. CONCLUSION: Dietary hop ß-acids fed to pigs might reduce lipid, increase protein and reduce lipid oxidation without affecting physical attributes of the pork meat. © 2017 Society of Chemical Industry.

On the reaction of lupulones, hops ß-acids, with 1-hydroxyethyl radical.

Lupulones, hops ß-acids, are one of the main constituents of the hops resin and have an important contribution to the overall bacteriostatic activity of hops during beer brewing. The use of lupulones as natural alternatives to antibiotics is increasing in the food industry and also in bioethanol production. However, lupulones are easy oxidizable and have been shown to be very reactive toward 1-hydroxyethyl radical with apparent bimolecular rate constants close to diffusion control k = 2.9 × 10(8) and 2.6 × 10(8) L mol(-1) s(-1) at 25.0 ± 0.2 °C in ethanol-water solution (10% of ethanol (v/v)) as probed by EPR and ESI-IT-MS/MS spin-trapping competitive kinetics, respectively. The free energy change for an electron-transfer mechanism is ΔG° = 106 kJ/mol as calculated from the oxidation peak potential experimentally determined for lupulones (1.1 V vs NHE) by cyclic voltammetry and the reported reduction potential for 1-hydroxyethyl radical. The major reaction products identified by LC-ESI-IT-MS/MS and ultrahigh-resolution accurate mass spectrometry (orbitrap FT-MS) are hydroxylated lupulone derivatives and 1-hydroxyethyl radical adducts. The lack of pH dependence for the reaction rate constant, the calculated free energy change for electron transfer, and the main reaction products strongly suggest the prenyl side chains at the hops ß-acids as the reaction centers rather than the ß,ß'-triketone moiety.