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不同种类啤酒花中黄腐酚含量的研究 总被引:4,自引:0,他引:4
以甲醇作溶剂采用超声波提取法对来自不同国家和地区的34个酒花样品中的黄腐酚进行了分离提取,并使用HPLC对其含量进行测定。结果表明不同类型的酒花之间黄腐酚含量存在很大的差异性,苦型啤酒花中黄腐酚含量要高于香型啤酒花;且酒花中黄腐酚的百分含量与α-酸的含量总体上呈现正相关的线性关系;酒花储藏时间的长短会影响黄府酚含量的高低;酒花由原花加工成酒花颗粒的过程中也会导致黄腐酚含量发生变化;此外,啤酒花的产地、年代等因素也都对黄腐酚含量有一定的影响。 相似文献
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目的研究不同光照条件,如光照强度、光照时间、处理光的波长等因素对啤酒花中黄腐酚(xanthohumol,Xn)光异构化的影响。方法啤酒花样品在不同光照强度、光照时间、波长和不同颜色玻璃瓶储藏条件下处理后,于OD_(370)处测量Xn含量。结果相同功率光源的紫外光引起Xn异构化较白光显著(P0.05),白光照射Xn样品随着光照时间和光照强度的增大,Xn光异构化程度提高;相同功率光源及光照时间条件下,红光[(625±5)nm]、黄光[(590±5) nm]、绿光[(555±5)nm]、蓝光[(450±5)nm]处理引起的Xn异构化速度差异极显著(P0.01),其中蓝光最强,其次是绿光、红光、黄光;白光光源光照条件下,深棕色玻璃瓶储存对Xn的稳定性显著优于绿色、蓝色、无色玻璃瓶等(P0.05),并且深棕色玻璃瓶长期储存Xn显著优于绿色玻璃瓶(P0.05)。结论光照时间、波长及储存条件对Xn光异构化有显著的影响,且避光储存利于Xn稳定,这为含有Xn的饮品、食品、保健品等的光照或包装条件的选择提供了依据。 相似文献
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利用硅胶柱层析法对啤酒花浸膏中的黄腐酚进行了分离,采取了2种洗脱方法。方法一是采用石油醚和乙酸乙酯固定比例(2:1)洗脱2次,第1次洗脱后合并含有黄腐酚的洗脱液,浓缩成浸膏,进行第2次洗脱;方法二是以石油醚和乙酸乙酯的混合溶剂梯度洗脱2次,第1次梯度洗脱后合并含有黄腐酚的洗脱液,浓缩成浸膏,进行第2次梯度洗脱。结果表明,方法一的分离效率高、速度快,黄腐酚得率较高(44.88%),但黄腐酚的纯度较低(57.78%);方法二的黄腐酚得率较低(43.16%),但纯度高(81.10%),部分馏分浓缩后有结晶析出,经HPLC检测为黄腐酚结晶单体,纯度达到98.1%,因此可以应用硅胶柱层析法高效分离和纯化啤酒花黄腐酚。 相似文献
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茶皂素提取纯化工艺和含量测定研究进展 总被引:1,自引:0,他引:1
本文介绍了茶皂素的化学结构和性质以及茶皂素标准品的制备和含量分析方法,重点叙述了茶皂素的提取和纯化工艺方法并指出各种方法的优缺点,希望能为油茶籽的综合利用提供参考。 相似文献
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Qi-he Chen Ming-liang FuMiao-miao Chen Jing LiuXiao-jie Liu Guo-qing HeShou-cheng Pu 《Food chemistry》2012,132(1):619-623
Xanthohumol (XN) and related prenylflavonoids are the main bioactive components of hops (Humulus lupulus L.). The current work is to investigate the use of high-speed counter-current chromatography (HSCCC) in search for high isolation of xanthohumol from hops. A solvent system consisted of n-hexane-ethyl acetate-methanol-water at a volume ratio of 5:5:4:3 was employed. The results demonstrated that the constructed method could be well applied for the isolation of xanthohumol from hops extract. After HSCCC isolation procedure, the purity of xanthohumol was over 95% assayed by HPLC and the yield of extraction was 93.60%. The chemical structure identification of xanthohumol was carried out by UV, 1H NMR and 13C NMR. The present results demonstrated that xanthohumol could be efficiently obtained using a single HSCCC step from H. lupulus L. extract. 相似文献
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Gerhäuser C 《Molecular nutrition & food research》2005,49(9):827-831
This review summarizes the capacity of xanthohumol (XN) in comparison with additional hop constituents and metabolites to act as an antiinfective agent against microorganisms including bacteria, viruses, fungi and malarial protozoa. XN was shown to inhibit the Gram-positive bacteria Staphylococcus aureus and Streptococcus mutans. Antiviral activity was demonstrated against bovine viral diarrhea virus, cytomegalovirus, herpes simplex virus type 1 and 2 and human immunodeficiency virus 1. Inhibition of two Trichophyton spp. was indicative of antifungal activity. Finally, XN potently inhibited the replication of Plasmodium falciparum, the causative agent of malaria. This effect was linked to the inhibition of glutathione-mediated degradation and detoxification of haemin, a by-product of the parasitic digestion of haemoglobin. Overall, these activities further contribute to the broad spectrum of biological effects observed with XN. 相似文献
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Pang Y Nikolic D Zhu D Chadwick LR Pauli GF Farnsworth NR van Breemen RB 《Molecular nutrition & food research》2007,51(7):872-879
Used in the brewing of beer, hops (Humulus lupulus L.) contain the prenylated chalcone xanthohumol, which is under investigation as a cancer chemoprevention agent and as a precursor for the estrogenic flavanones isoxanthohumol and 8-prenylnaringenin. The uptake, transport and accumulation of xanthohumol were studied using the human intestinal epithelial cell line Caco-2 to help understand the poor bioavailability of this chalcone. Studies were carried out using Caco-2 cell monolayers 18-21 days after seeding. The apparent K(m) and V(max) values of xanthohumol accumulation in Caco-2 cells were determined, and the protein binding of xanthohumol in sub-cellular fractions of Caco-2 cells was investigated. Approximately 70% of xanthohumol added to the apical side of Caco-2 cells accumulated inside the cells, while 93% of the intracellular xanthohumol was localized in the cytosol. Xanthohumol accumulation was temperature dependent and saturable with an apparent K(m )value of 26.5 +/- 4.66 muM and an apparent V(max) of 0.215 +/- 0.018 nmol/mg protein/min. Facilitated transport was not responsible for the uptake of xanthohumol, instead, accumulation inside the Caco-2 cells was apparently the result of specific binding to cytosolic proteins. These data suggest that specific binding of xanthohumol to cytosolic proteins in intestinal epithelial cells contributes to the poor oral bioavailability observed previously in vivo. 相似文献
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通过单因素和正交试验确定了酒花多酚的最佳提取工艺:浸提剂为70%丙酮,料液比1:25(g/ml),回流提取温度45℃,提取时间为1h,在此条件下多酚的提取量达到47.29mg/g干酒花。抗氧化实验结果显示酒花多酚对DPPH自由基的清除能力(IC506.72μg/ml)优于抗坏血酸(IC508.79μg/ml)和单宁酸(IC507.68μg/ml),弱于茶多酚(IC505.77μg/ml);酒花多酚的还原力(EC500.111mg/ml)与抗坏血酸(EC500.101mg/ml)接近,弱于单宁酸(EC500.079mg/ml)和茶多酚(EC500.072mg/ml);酒花多酚对小鼠肝匀浆脂质过氧化产生丙二醛(MDA)的抑制能力(IC500.179mg/ml)优于单宁酸(IC500.462mg/ml),弱于茶多酚(IC500.136mg/ml)。 相似文献
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Miha Ocvirk Jože Grdadolnik Iztok Jože Košir 《Journal of the Institute of Brewing》2016,122(3):452-461
Beer flavour and aroma depend mostly on the hop variety used in the brewing process. For this reason it is of crucial importance for brewers to be certain about the botanical origin of the hop variety. Metabolic fingerprinting is one of the approaches that can be used for determination of the botanical origin of many agricultural and food products. The aim of the current work was to differentiate between the five most important hop varieties in Slovenia. Gas chromatography, high‐performance liquid chromatography (HPLC) and Fourier transform infrared spectroscopy were carried out in combination with three different chemometric methods – principal component analysis, regularized discriminant analysis and hierarchical clustering – on 121 hop samples. The chemometric classification of the hop varieties was obtained with nearly 100% success. The best results were obtained with GC and HPLC data, within one year of harvesting. Copyright © 2016 The Institute of Brewing & Distilling 相似文献
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