FOOD CHEMISTRY
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2024
·
IF 8.5
Huijuan Gao,Qian Wang,Qiangli Qi,Wenjing He,Wen Li
Hops , extensively cultivated in China for their food and medicinal applications, currently lack well-defined chemical markers to evaluate variations in their quality. The study aimed to explore variations in the quality of Chinese hops by the chemical characteristics of hops, employing UPLC-Q-TOF/MS, integrated with chemical fingerprinting and chemometrics. The results indicated that Chinese hops are abundant in polyphenols and bitter acids. The integration of UPLC-Q-TOF/MS, Chemical fingerprinting, and chemometrics revealed to be an accurate and effective approach for assessing the quality of Chinese hops. In this study, ten important chemical markers were found to be useful in differentiating various hop varieties. Moreover, the support vector machine showed a prediction accuracy of 92.3077% in identifying Chinese hop varieties. The strategy of the study lays the groundwork for classifying Chinese hop varieties and serves as a prerequisite for future quality control studies, particularly focusing on chemical compositions.
研究领域:
植物化学
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分析化学
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药学
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产品关联
DOI
PubMed
高影响因子
Antioxidants
·
2022
·Vol. 11
·期 4
·772
·
IF 7.675
Jiaman Liu,Yanbiao Chen,Xinxin Zhang,Jie Zheng,Weiying Hu,Bo Teng
The application of hops could be extended to obtain higher commercial values. Tannins from hops were assessed for their tyrosinase inhibition ability, and the associated mechanisms were explored. Nuclear magnetic resonance (NMR) and high-performance liquid chromatography–electrospray ionization–tandem mass spectrometry (HPLC–ESI–MS/MS) revealed that the hop tannins were characterized as condensed tannins with (epi)catechin and (epi)gallocatechin as subunits and an average polymerization degree of 10.32. Tyrosinase inhibition assay indicated that hop tannins had an IC50= 76.52 ± 6.56 μM. Kinetic studies of the inhibition processes indicated the tannins provided inhibition through competitive–uncompetitive mixed reactions. In silico molecule docking showed that tannins were bound to the active site of tyrosinase via hydrogen and electrovalent bonds. Circular dichroism (CD) observed the structural variation in the tyrosinase after reacting with the tannins. Fluorescence quenching analysis and free radical scavenging assays indicated that the tannins had copper ion chelating and antioxidant activities, which may also contribute to inhibition. The intracellular inhibition assay revealed that the melanin was reduced by 34.50% in B16F10 cells. These results indicate that these tannins can be applied as whitening agents in the cosmetics industry.Keywords:hop tannins;polyphenols;condensed tannin;tyrosinase inhibitor;whitening agent
研究领域:
药理学
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化妆品学
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生物化学
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DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2021
·
IF 7.514
Limin Wang,Yunsen Zhang,I. Agbaka Johnpaul,Kai Hong,Yumei Song,Xiao Yang,Chenyan Lv,Changwei Ma
Hops are abundant in natural bioactive compounds. In this work, nine prenylated bitter compounds from hop were evaluated for their inhibitory activity against α-glucosidase. As a result, four flavonoids and one phloroglucinol (lupulone, LP) outperformed acarbose in inhibiting α-glucosidase. Isoxanthohumol (IX) and LP with two types of structures were selected for inhibition mechanism studies by spectroscopic methods and molecular dynamics simulation (MD). Results showed that IX acted as noncompetitive inhibitor and bound to α-glucosidase in allosteric sites via hydrogen bonds, hydrophobic, van der Waals (vdW), and electrostatic force, whereas LP was uncompetitive inhibitor and bound to catalytic sites via hydrophobic and vdW interactions. Notably, the conformation around binding site of α-glucosidase formed stable α-helix and tightened after binding IX and LP, respectively, which helped to elucidate noncompetitive and uncompetitive inhibitory mechanisms. This work demonstrated that two types of prenylated bitter compounds are discrepant in their mechanisms of interaction with α-glucosidase.
研究领域:
植物化学
·
生物化学
·
药理学
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产品关联
DOI
PubMed
高影响因子
FOOD CONTROL
·
2021
·
IF 5.548
Kai Hong,Zhenzhen Xu,Limin Wang,Agbaka Johnpaul,Yongqiang Cheng,Chenyan Lv,Changwei Ma
Humulus lupulus (hop) cone is a key ingredient in beer, which determines its taste and aroma. The impact of ripening on the bitter acids, aroma compounds, and polyphenols of hops has been reported separately, there is no systematic study on all three components. Here, three hop varieties (‘TP1’, ‘TP2’, and ‘QTF’) in China were sampled to investigate the correlation between the harvest maturity and these three components, which indicated that polyphenols synthesized earlier than hop bitter acids, followed by the aroma compounds. Variety differences of the hop cultivars prompted the obvious separation in the partial least-squares discriminant analysis (PLS-DA). Among three hop cultivars. ‘TP1’ with the highest contents of aroma compounds contributed to flower aroma, and with higher contents of bitter acids which contributed to bitter taste. In contrast, ‘TP2’ has been reported to be rich in caffeic acid, salicylic acid, syringaldehyde, (+)-catechin, and (−)-epicatechin. To analyze the hop aroma characteristics, two matrices of hop tea and late-hopped beer were prepared and used for sensory evaluation. Compared to ‘TP2’ and ‘QTF’, the hop tea with ‘TP1’ scored best for ‘strong’ (P < 0.01), ‘herbal’ (P < 0.05) and ‘citrus’ (P < 0.01). While the ‘strong’ and ‘herbal’ characteristics from terpene compounds receded in the late-hopped beer, the ‘citrus’ and ‘fruity’ notes from terpenol compounds remained noticeable.
研究领域:
植物科学
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农学
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食品科学
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化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）