The impact of high intensity ultrasound (US, 45 and 20 kHz) on a purified macromolecular fraction (more than 85% of polymeric procyanidins) from grape seed extract was investigated. Matrix-Assisted Laser Desorption/Ionisation (MALDI TOF), Reverse Phase High Performance Liquid Chromatography (RP-HPLC) and Fourier-transform infrared spectroscopy (FTIR) revealed a modification in the chemical structure of these macromolecules treated by US and, particularly, bath US produced a considerable increase of up to 49, 41 and 35%, respectively, of catechins and oligomeric and polymeric procyanidin contents of the treated purified fraction. Bath US also produced, an important increase in the number of procyanidins with higher molecular mass (up to decamers) and an overall increase in the mass signal intensities in most of the detected B-type procyanidin series, as well as an important increase of the antioxidant activity of the macromolecular fraction of procyanidins. These results could be ascribed to a certain disaggregation of procyanidins linked to other biopolymers, such as proteins and/or polysaccharides, indicating that US is an efficient technology to modify the chemical structure and hence the bioactivity of tannins.

研究了高强度超声（美国，45和20 kHz）对葡萄籽提取物中纯化的大分子部分（聚合原花青素的85％以上）的影响。基质辅助激光解吸/电离（MALDI TOF），反相高效液相色谱（RP-HPLC）和傅立叶变换红外光谱（FTIR）显示，这些经过美国处理的大分子，尤其是镀液处理后的大分子的化学结构发生了变化US处理的纯化级分的儿茶素以及低聚和聚合原花青素含量分别显着提高了49％，41％和35％。巴斯美国公司也生产，在大多数检测到的B型原花青素系列中，具有较高分子量的原花青素数量（最多达到十聚体）显着增加，质量信号强度总体增加，并且大分子的抗氧化活性显着增加原花青素的一部分。这些结果可以归因于与其他生物聚合物（例如蛋白质和/或多糖）连接的原花青素的某种​​分解，表明US是一种有效的技术，可以改变丹宁酸的化学结构及其生物活性。