•Green methods to obtain hop extracts rich in bioactive compounds were proposed.•Efficiency of ultrasound- and microwave-assisted extraction of hops were compared.•Microwave-assisted extraction with ...ethanol produced 2.5 times more xanthohumol than ultrasounds.•1H-NMR fingerprinting of hop green extracts was carried out.•Trigonelline was identified in the hop aqueous extracts.
Currently, there is a continuous growth in demand for medicinal and aromatic plant derived molecules obtained in a sustainable and eco-friendly way. Among the medicinal plants that have a plethora of health-related properties, there is definitely hops. In the present study, microwaves (MW) and ultrasounds (US) were used to increase the extraction efficiency of bioactive compounds from hop cones using water, ethanol and their mixture as food-grade solvents. A multidisciplinary approach was used for the in-depth characterization of green extracts. The bioactive components were determined by chemical methods, using both spectrophotometric assays as well as high-performance liquid chromatography with diode-array detection (HPLC-DAD) analysis of individual phenols, bitter acids and xanthohumol, and results were compared with those from a control extract, obtained using aqueous methanol (80 %) acidified with HCl (0.1 %). Moreover, we applied proton nuclear magnetic resonance (1H-NMR) spectroscopy to reveal insights on the different composition in terms of primary and secondary metabolites of the green extracts analyzed. Generally, microwave-assisted extraction (MAE) of hop cones with ethanol showed the strongest extraction power for almost all the bioactive compounds investigated, as well as the shortest extraction time (1 min) and the highest antiradical capacity. 1H-NMR analyses showed an overall greater influence of solvent polarity, rather than extraction technique, on the average composition of the final extract. 1H-NMR fingerprinting of hop aqueous extracts highlighted as main components sugars and amino acids, as well as other metabolites including trigonelline, an alkaloid with interesting biological properties. However, the two extraction techniques significantly affected the contribution of signals in the terpene or aromatic regions when ethanol and ethanol:water were used as solvents, proving a better extraction efficiency for these compounds of MW than US. Regardless the extraction technique and solvent used, the most abundant polyphenol compound in the green extracts analyzed was catechin, ranging from 2989 ± 10 to 14009 ± 248 μg g−1 (for UAEETOH and MAEETOH, respectively), followed by rutin and chlorogenic acid. 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-Azinobis 3-ethylbenzothiazoline-6-sulfonic acid-diammonium salt (ABTS) radical scavenging methods were used to evaluate the biological properties of green hop extracts, showing a superior free-radical scavenging capacity in MW irradiated ethanol samples compared to other samples tested. The inter-relationships between the parameters analyzed and the different extraction conditions, as well as the relationships among variables, were investigated by principal component analysis.
Cannabis sativa
L. is an important yet controversial plant with a long history of recreational, medicinal, industrial, and agricultural use, and together with its sister genus
Humulus
, it represents ...a group of plants with a myriad of academic, agricultural, pharmaceutical, industrial, and social interests. We have performed a meta-analysis of pooled published genomics data, andwe present a comprehensive literature review on the evolutionary history of
Cannabis
and
Humulus
, including medicinal and industrial applications. We demonstrate that current
Cannabis
genome assemblies are incomplete, with ∼10% missing, 10-25% unmapped, and 45S and 5S ribosomal DNA clusters as well as centromeres satellite sequences not represented. These assemblies are also ordered at a low resolution, and their consensus quality clouds the accurate annotation of complete, partial, and pseudogenized gene copies. Considering the importance of genomics in the development of any crop, this analysis underlines the need for a coordinated effort to quantify the genetic and biochemical diversity of this species.
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•Ethanolic extracts of beer hop show high antibacterial activity against B. subtilis.•Activity-guided fractionation detected strongest effect for lupulone and adlupulone.•Metabolome ...profiling associated 33 out of 1826 features with antibacterial activity.•Antibacterial activity values were determined including concentration and activity.•Colupulone and lupulone were the main contributors to the activity of the extracts.
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.
The booming craft beer industry, rising prices of hops, and demand for locally-produced ingredients have recently increased interest in local hop production among growers and brewers. This article ...describes crop management practices and labor inputs required for small-scale hop production in Florida, with the aim of assisting growers with investment and farm management decisions. It is part of a larger series that will review the challenges of hop production in Florida, based on research experience at the UF/IFAS Gulf Coast Research and Education Center in Balm, FL. This new 6-page publication of the UF/IFAS Horticultural Sciences Department was written by Shinsuke Agehara, Mariel Gallardo, Aleyda Acosta-Rangel, Zhanao Deng, Jack Rechcigl, Tianyuan Luo, and Qi Qiu.https://edis.ifas.ufl.edu/hs1409
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 GABAA receptors and bring further insight into the mode of action behind the sedative properties of hops. GABA-potentiating effects were measured using 3Hethynylbicycloorthobenzoate (EBOB) radioligand binding assay in native GABAA receptors. Flumazenil sensitivity of GABA-potentiating effects, 3HRo 15–4513, and 3Hflunitrazepam 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 3HEBOB binding in a concentration-dependent manner where the IC50 values for this potentiation in native GABAA receptors were 3.2 μM and 3.7 μM, respectively. Flumazenil had no significant effects on humulone- or 6-prenylnaringenin-induced displacement of 3HEBOB binding. 3HRo 15–4513 and 3Hflunitrazepam 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 GABAA receptor α1β2γ2 isoform. Radioligand binding and docking results suggest a dual mode of action by 6-prenylnaringenin on GABAA 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.
•Bioactive compounds of hop were quickly and simply extracted with aqueous solvents.•The solvents included hot water as well as 55%, 75%, and 95% ethanol solutions.•Both anti-oxidative and ...anti-inflammatory activities of the extracts were evaluated.•The hop ethanol extracts (HEEs) had more polyphenols, flavonoids, and bitter acids.•The HEEs showed high anti-oxidative and partial anti-inflammatory activities.
The aim of this study is to simultaneously evaluate anti-oxidative and anti-inflammatory activities of the hop extracts by different solvents. Hop water extract (HWE) and hop ethanol extracts (HEEs) were prepared by extracting hop pellets with hot water at 90 °C and ethanol solutions (55%, 75%, and 95%), respectively. Bioactive compound such as α-acid, β-acid, total phenolic, and total flavonoid contents were determined. All the HEEs showed higher anti-oxidative activities than the HWEs. The HEEs showing the highest anti-oxidative activities are different in the experiments with different free radicals. For anti-inflammatory activities, both the HWE and HEEs decreased NO productions. HWE decreased TNF-α and IL-6 secretion but showed no effect on IL-1β, while HEEs decreased IL-1β and IL-6 secretion but increased TNF-α secretion. Except for TNF-α secretion, the HEEs showed higher anti-inflammatory activities than the HWE. Future work is to explore the possible mechanism to improve the ethanol extraction procedure.
본 연구는 호프 추출물을 건강기능식품 개별인정원료로 개발하기 위해 원료 표준화를 위한 지표성분으로 xanthohumol을 설정하고 이에 대한 HPLC 분석법 유효성 검증을 실시하였다. 분석법의 유효성 검증은 식품의약품안전처 건강기능식품 기능성 원료 인정을 위한 제출자료 작성 가이드와 ICH 가이드라인에 근거하여 특이성, 직선성, 정확성, 정밀성, 검출한계 ...및 정량한계를 통해 신뢰성 및 타당성을 검증하였다. 지표성분 xanthohumol 분석을 위해 0.1% formic acid가 첨가된 water 및 95% acetonitrile을 이동상으로 사용하였고 컬럼은 Capcell pak C18을 사용하여 HPLC를 이용하여 분석하였다. 표준용액과 호프 추출물의 지표성분 xanthohumol의 피크 머무름시간은 일치하고 다른 물질의 간섭을 받지 않는 것을 확인했으며, UV/visible spectrum이 일치하므로 특이성을 확인하였다. Xanthohumol 검량선의 상관계수(R2)는 0.9999 이상으로 나타나 높은 직선성을 보여 분석에 적합한 것으로 확인되었다. 호프 추출물에 xanthohumol 표준용액을 5, 25, 50 μg/mL의 3개 수준으로 첨가하고 분석한 회수율은 96.76~102.93%로 나타나 높은 정확성이 있는 것을 확인할 수 있었다. 정밀성은 반복성과 재현성으로 확인했으며, 호프 추출물 125~500 mg 범위에서 시료량의 변화에 따른 반복성은 RSD 0.32~0.85%로 나타났고 실험자를 달리한 재현성 검증 결과 RSD는 0.18~ 0.70%로 확인되어 본 분석법은 정밀성이 있음을 확인하였다. 반응의 표준편차와 검량선의 기울기에 근거한 검출한계는 0.26 μg/mL였고 정량한계는 0.80 μg/mL로 호프 추출물의 xanthohumol 함량 분석을 위한 적합한 한계수준으로 확인되었다. 이상의 결과로 호프 추출물의 지표성분인 xanthohumol의 HPLC 분석법은 국내외 가이드라인에 적합한 시험법으로 검증되었다. 또한 검증된 분석법을 이용하여 호프 추출물의 xanthohumol 함량을 분석한 결과 6.40±0.75 mg/g으로 분석되었다. 본 시험법은 호프 추출물의 건강기능식품 개별인정원료 개발을 위한 표준화의 기초자료로 활용될 것으로 사료된다. This study was performed to establish a high-performance liquid chromatography (HPLC) analytical method for determining xanthohumol in hop (Humulus lupulus) extract for its standardization as a functional ingredient. The analytical method was validated based on the ‘Guideline on Preparing Dossiers for Functional Ingredient Recognition of Health Functional Food’ of the Ministry of Food and Drug Safety of Korea and the International Conference on Harmonization guidelines to determine its reliability and validity in terms of specificity, linearity, accuracy, precision, limit of detection (LOD) and limit of quantification (LOQ). The specificity was confirmed by the chromatogram obtained from the HPLC analysis method, as well as by the results of ultraviolet/visible spectra. The correlation coefficient (R2) was calculated to be close to 1, confirming that this was a suitable analysis with high linearity. Xanthohumol recovery ranged from 96.76 to 101.30% with relative standard deviation (RSD) values of less than 5%, and the repeatability and reproducibility of precision were confirmed to be 0.32∼0.85% and 0.18∼0.70% for the RSD, respectively, which implies that this method has high accuracy and precision. In addition, the LOD was 0.26 μg/mL, and the LOQ was 0.80 μg/mL, confirming that detection was valid at low concentrations. These results indicate that the proposed HPLC method for the detection of xanthohumol in hop extract is simple, reliable, and reproducible. KCI Citation Count: 0
Xanthohumol (XN) is a unique prenylated flavonoid in hops (Humulus lupulus L.) and beer. XN alleviates hyperglycemia and has potential usage in the treatment of type 2 diabetes. In the present study, ...a series of in vitro experiments were performed to investigate whether XN was an effective inhibitor of α-glucosidase. The results showed that XN inhibited α-glucosidase in a reversible and noncompetitive manner, with an IC50 value of 8.8 μM and that XN inhibited the release of glucose from the maltose in the apical side of the Caco-2 cell monolayer. Fluorescence and circular dichroism spectra results indicated that XN directly bound to α-glucosidase and induced minor conformational changes of the enzyme. These results demonstrated that XN is a promising α-glucosidase inhibitor, which therefore could be used as functional food to alleviate postprandial hyperglycemia and as a potential candidate for the development of an antidiabetic agent.
Volatile thiol 3-mercaptohexan-1-ol (3MH) and particularly 4-mercapto-4-methylpentan-2-one (4MMP) are highly potent flavour compounds in hops. For the determination, a simple and robust stable ...isotope dilution LC–MS/MS method was developed and applied to 32 hop varieties worldwide from harvest years 2019 and 2020. Limit of detection, precision, and recovery were 0.15 μg/kg, 10%, and 97–108%, respectively. Levels of 3MH and 4MMP ranged from 1.9 to 79.2 μg/kg and from undetectable to 37.1 μg/kg, respectively. Citra, Mosaic, and Strata were rich in both thiols. ICP analyses revealed, that variation of potassium content between the two harvest years was inversely correlated with that of manganese and rubidium (|r| ≥ 0.89) among 12 US varieties excluding Citra and Mosaic. Total essential oil content (0.34–2.7 mL/100 g) was inversely correlated with calcium content (|r| ≥ 0.65). Greatly varying thiol levels depending on variety, region and harvest year might lead to differing flavour results in beer.
•A simple and robust LC–MS/MS method for free thiol analysis in hops was established.•US Citra, Mosaic and Strata were rich in both thiols.•Ca content was inversely correlated with total essential oils (Pearson's |r| ≥ 0.65).•Remarkable deviation in K & P contents (14%) was seen in Mosaic between two harvests.
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