Pacheco Ana Flávia Coelho, Pacheco Flaviana Coelho, Cunha Jeferson Silva, Nalon Gabriela Aparecida, Gusmão Jhonathan Valente Ferreira, Santos Fábio Ribeiro Dos, Andressa Irene, Paiva Paulo Henrique Costa, Tribst Alline Artigiani Lima, Leite Junior Bruno Ricardo de Castro
Instituto de Laticínios Cândido Tostes, Empresa Agropecuária de Minas Gerais (EPAMIG), Tenente Luiz de Freitas, 116, Juiz de Fora 36045-560, MG, Brazil.
Department of Food Technology (DTA), Federal University of Viçosa (UFV), Viçosa 36570-900, MG, Brazil.
Foods. 2025 Feb 25;14(5):782. doi: 10.3390/foods14050782.
Pumpkin seed proteins (PSPs) are a promising resource for obtaining bioactive peptides but their low solubility hinders enzymatic hydrolysis, reducing yield and bioactivity. In addition, enzymatic processes require specific conditions and long processing times; improving the efficiency of this process is essential to expand its industrial applications. In this context, using a high-frequency, low-intensity ultrasound (US) has proven to be an effective strategy for optimizing the hydrolysis of plant protein. This study evaluated the US-assisted (38 W/L, 40 kHz) and conventional hydrolysis of pumpkin seed proteins (PSPs) for 180 min at 25 °C, 40 °C, and at the optimum temperature condition for each enzyme studied (60 °C for Brauzyn, 55 °C for Flavourzyme, and 50 °C for Neutrase), as well as the impact of this process on the macrostructural and functional characteristics of the hydrolysates obtained. The degree of hydrolysis (DH) was significantly higher in US-assisted reactions, reaching increases of up to 57.7% with Neutrase at 40 °C. The US also positively influenced the protein solubility of the hydrolysates, especially at pH levels close to the isoelectric point, with improvements of up to 100%, compared to the hydrolysates obtained from the conventional reaction. The antioxidant activity was also enhanced by the US, compared to the conventional reaction, emphasizing the hydrolysates obtained through the action of Flavourzyme, which showed increases of 52.4% and 42.6% in the scavenging of DPPH and ABTS radicals, respectively. The analysis of the mean particle size revealed significant reductions with the US (<26.2%). Consequently, the polydispersity index (PDI) demonstrated greater uniformity in the particles obtained from the US-assisted reactions (reductions of up to 20.3%). UV-Vis spectroscopy and intrinsic fluorescence also indicated possible alterations in the tertiary structure of the peptides obtained, mainly in US-assisted reactions. Therefore, US-assisted PSP hydrolysis resulted in better enzymatic performance and produced protein hydrolysates with bioactive potential for food applications.
南瓜籽蛋白（PSPs）是获取生物活性肽的一种有前景的资源，但其低溶解度阻碍了酶解过程，降低了产量和生物活性。此外，酶促过程需要特定条件且处理时间长；提高该过程的效率对于扩大其工业应用至关重要。在此背景下，使用高频、低强度超声（US）已被证明是优化植物蛋白水解的有效策略。本研究评估了在25℃、40℃以及所研究的每种酶的最佳温度条件（Brauzyn为60℃、Flavourzyme为55℃、Neutrase为50℃）下，超声辅助（38W/L，40kHz）和常规方法对南瓜籽蛋白（PSPs）进行180分钟水解的情况，以及该过程对所得水解产物的宏观结构和功能特性的影响。在超声辅助反应中，水解度（DH）显著更高，在40℃使用Neutrase时增幅高达57.7%。超声还对水解产物的蛋白质溶解度产生积极影响，尤其是在接近等电点的pH水平下，与常规反应所得水解产物相比，溶解度提高了100%。与常规反应相比，超声也增强了抗氧化活性，特别强调了通过Flavourzyme作用获得的水解产物，其对DPPH和ABTS自由基的清除率分别提高了52.4%和42.6%。平均粒径分析显示超声处理后粒径显著减小（<26.2%）。因此，多分散指数（PDI）表明超声辅助反应所得颗粒的均匀性更高（降低了20.3%）。紫外可见光谱和内源荧光也表明所得肽的三级结构可能发生了变化，主要是在超声辅助反应中。因此，超声辅助的PSP水解导致了更好的酶促性能，并产生了具有食品应用生物活性潜力的蛋白质水解产物。
