Řepka David, Lapčík Lubomír
Department of Physical Chemistry, Faculty of Science, Palacky University, 17. Listopadu 12, 771 46 Olomouc, Czech Republic.
Department of Foodstuff Technology, Faculty of Technology, Tomas Bata University in Zlin, Nam. T.G. Masaryka 275, 762 72 Zlin, Czech Republic.
Foods. 2025 Apr 23;14(9):1458. doi: 10.3390/foods14091458.
In this study, we compared different parameters in the ultrasound-assisted extraction of polyphenolic acids from seven parts of (kernels, leaves, stems, corn silks, roots, the whole plant, and the whole fermented plant) to identify its richest natural sources. Additionally, the correlation between extraction parameters and polyphenol yield was investigated. The extraction was performed using ultrasound at varying powers (480 or 240 W) and frequencies (80 or 37 kHz). Total phenolic content (TPC) was determined using the Folin-Ciocalteu assay, while radical scavenging activity (RSA) was assessed via the DPPH assay. The TPC values ranged from 0.69 ± 0.00008 mg GAE/g to 4.07 ± 0.0004 mg GAE/g in corn. RSA analysis revealed the highest scavenging activity in corn silk (80.06% ± 1.01) and the lowest in kernels (2.77% ± 0.90). High-performance liquid chromatography identified up to 22 different phenolic acids per sample, with the 5 most abundant being chlorogenic acid, protocatechuic acid ethyl ester, quercetin, sinapic acid, and -cinnamic acid. The study found small effects of power and frequency on the extraction efficiency. This suggests a practical advantage for industrial-scale applications, as using 240 W instead of 480 W under the same conditions can reduce energy consumption without compromising yield.
在本研究中，我们比较了从[植物名称]的七个部位（果仁、叶片、茎、玉米须、根、全株以及全株发酵体）超声辅助提取多酚酸的不同参数，以确定其最丰富的天然来源。此外，还研究了提取参数与多酚产量之间的相关性。提取过程使用不同功率（480或240瓦）和频率（80或37千赫）的超声波进行。总酚含量（TPC）采用福林 - 西奥尔特法测定，而自由基清除活性（RSA）通过DPPH法评估。玉米中的TPC值范围为0.69±0.00008毫克没食子酸当量/克至4.07±0.0004毫克没食子酸当量/克。RSA分析表明，玉米须的清除活性最高（80.06%±1.01），果仁的清除活性最低（2.77%±0.90）。高效液相色谱法鉴定出每个样品中多达22种不同的酚酸，其中含量最高的5种为绿原酸、原儿茶酸乙酯、槲皮素、芥子酸和肉桂酸。研究发现功率和频率对提取效率的影响较小。这表明在工业规模应用中具有实际优势，因为在相同条件下使用240瓦而非480瓦可以在不影响产量的情况下降低能耗。
