Masek Anna, Chrzescijanska Ewa, Kosmalska Anna, Zaborski Marian
Technical University of Lodz, Institute of Polymer and Dye Technology, Faculty of Chemistry, ul Stefanowskiego 12/16, 90-924 Lodz, Poland.
Technical University of Lodz, Institute of General and Ecological Chemistry, Faculty of Chemistry, ul Zeromskiego 116, 90-924 Lodz, Poland.
Food Chem. 2014 Aug 1;156:353-61. doi: 10.1016/j.foodchem.2014.02.005. Epub 2014 Feb 12.
The article presents the antioxidant properties of the extracts of hop EI and EII, by the electrochemical methods on a platinum electrode and comparative analysis of the composition of the extracts of hops using UV-VIS, FTIR and GC-MS methods. The hops extract EI, was obtained from the waste of the hops cone. The hops extract EII, was obtained from the hops cone itself. Hops contain a wide range of polyphenolic compounds with antioxidant properties divided in various chemical classes. Flavonoids and other polyphenolic compounds contained in hops show antioxidant capacity because of the presence of hydroxyl groups in various configurations and numbers within their molecules. The electrochemical properties and antioxidant capacity of hop samples were determined to select the most effective antioxidant. Based on the cyclic and pulse voltammograms, it was observed that hop extract EI contains polyphenols that are oxidised at a less positive potential than extract EII, i.e., it shows better antioxidant capacity. From the analysis of the UV-VIS and FTIR spectra and the GC-MS analysis, it was observed that extract EI contains less phenyl compounds than EII. In addition to flavonoids, EII contains hop acids and chlorophyll. The solutions of hop extracts show very good antioxidant capacities; therefore, they can effectively inhibit or slow negative oxidation reactions and scavenge free radicals and reactive oxygen species (ROS).
本文通过在铂电极上的电化学方法，以及使用紫外可见光谱（UV-VIS）、傅里叶变换红外光谱（FTIR）和气相色谱-质谱联用（GC-MS）方法对啤酒花提取物成分进行比较分析，介绍了啤酒花EI和EII提取物的抗氧化特性。啤酒花提取物EI是从啤酒花球果的废料中获得的。啤酒花提取物EII是从啤酒花球果本身获得的。啤酒花含有多种具有抗氧化特性的多酚类化合物，这些化合物分为不同的化学类别。啤酒花中含有的黄酮类化合物和其他多酚类化合物因其分子内存在不同构型和数量的羟基而具有抗氧化能力。测定了啤酒花样品的电化学性质和抗氧化能力，以选择最有效的抗氧化剂。基于循环伏安图和脉冲伏安图，观察到啤酒花提取物EI中含有的多酚在比提取物EII更正的电位下被氧化，即它显示出更好的抗氧化能力。通过对紫外可见光谱和傅里叶变换红外光谱的分析以及气相色谱-质谱联用分析，观察到提取物EI中的苯基化合物比EII少。除了黄酮类化合物外，EII还含有啤酒花酸和叶绿素。啤酒花提取物溶液显示出非常好的抗氧化能力；因此，它们可以有效地抑制或减缓负面氧化反应，并清除自由基和活性氧（ROS）。
