Key Laboratory of Food Processing in Jiangsu Province of China, School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu 212013, China.
Key Laboratory of Food Processing in Jiangsu Province of China, School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu 212013, China.
Ultrason Sonochem. 2018 Jan;40(Pt A):890-899. doi: 10.1016/j.ultsonch.2017.08.028. Epub 2017 Aug 26.
The effects of ultrasound-assisted α-amylase degradation (UAD) treatment with multiple modes on the extraction of rice protein (RP) from rice dreg powder were studied. The results showed that UAD treatment increased protein extraction rate significantly (p<0.05) compared to that of α-amylase degradation treatment and control. Among all the ultrasound mode treatments researched in this paper, sequential frequency ultrasound treatment presented higher protein extraction rate compared to that of simultaneous or single frequency ultrasound treatment. The highest protein extraction rate was obtained under 20/35kHz of sequential frequency UAD treatment with the protein extraction rate of 89.58% and protein purity of 92.99%. The test and analysis of fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, starch content, non-protein nitrogen content, SH and SS content, surface hydrophobicity, amino acids content and proteins characteristics were studied to reveal the mechanism of UAD on the protein extraction effect. After treated with UAD, the starch-protein agglomerates disintegrated completely, moreover, protein advanced structure was changed to some extent and the disulfide bond was partially broken, but the main chain structure (peptide chain), specificity of protein and amino acid composition were not obviously changed. Consequently, the structure modified RP extracted by UAD treatment presented higher solubility, emulsifying activity and foaming capacity, which was beneficial for the application of RP. In conclusion, UAD treatment is an effective method for maximizing extraction rate, purity and modifying properties of extracted protein.
研究了多模式超声辅助α-淀粉酶降解（UAD）处理对从米渣粉中提取大米蛋白（RP）的影响。结果表明，与α-淀粉酶降解处理和对照组相比，UAD 处理显著提高了蛋白质提取率（p<0.05）。在本文研究的所有超声模式处理中，顺序频率超声处理的蛋白质提取率高于同时或单频超声处理。在 20/35kHz 的顺序频率 UAD 处理下，获得了最高的蛋白质提取率，为 89.58%，蛋白质纯度为 92.99%。通过傅里叶变换红外光谱、紫外-可见光谱、淀粉含量、非蛋白氮含量、SH 和 SS 含量、表面疏水性、氨基酸含量和蛋白质特性的测试和分析，揭示了 UAD 对蛋白质提取效果的作用机制。经过 UAD 处理后，淀粉-蛋白质聚集体完全解体，此外，蛋白质的高级结构也发生了一定程度的变化，二硫键部分断裂，但蛋白质的主链结构（肽链）、特异性和氨基酸组成没有明显变化。因此，经 UAD 处理提取的结构修饰 RP 具有更高的溶解度、乳化活性和起泡能力，有利于 RP 的应用。总之，UAD 处理是一种有效提高提取率、纯度和修饰提取蛋白性质的方法。
