Department of Chemical and Biological Engineering, Monash University, Clayton, VIC 3800, Australia.
Department of Chemical and Biological Engineering, Monash University, Clayton, VIC 3800, Australia.
Food Chem. 2023 Jun 15;411:135464. doi: 10.1016/j.foodchem.2023.135464. Epub 2023 Jan 11.
Lentils and mungbean proteins are under-researched compared to pea and soybean. Lentils (green, red and black-lentils), mungbean and yellow pea protein isolates were obtained by alkaline extraction (pH 9)-isoelectric precipitation (pH 4.5) and investigated for molecular and higher-order structures using complementary and novel approaches. These extracted isolates showed comparable protein content but significantly greater nitrogen solubility index (NSI > 85 %) than commercial pea and soy protein isolates (NSI < 60 %). Based on molecular weight estimations from sodium dodecyl sulphate-polyacrylamide gel electrophoresis analysis, the soluble proteins of lentils and yellow pea were identified as legumin-like and vicilin-like, while mungbean was dominated by vicilin-like proteins. The soluble extracts were confirmed to be in native structural condition by size exclusion chromatography and nano-differential scanning calorimetry, unlike commercial extracts. Further differences in secondary structure were evident on circular dichroism spectra of the soluble extracts and deconvolution of the Amide I region (1700-1600 cm) from Fourier Transform Infrared of the total protein.
与豌豆和大豆相比，扁豆和绿豆蛋白的研究较少。通过碱性提取（pH9）-等电沉淀（pH4.5）获得了扁豆（绿、红和黑扁豆）、绿豆和黄豌豆蛋白分离物，并使用互补和新颖的方法研究了它们的分子和高级结构。这些提取的分离物具有可比的蛋白质含量，但氮溶解度指数（NSI>85%）明显高于商业豌豆和大豆蛋白分离物（NSI<60%）。基于十二烷基硫酸钠-聚丙烯酰胺凝胶电泳分析的分子量估算，扁豆和黄豌豆的可溶性蛋白被鉴定为类球蛋白和豆球蛋白样，而绿豆则主要由豆球蛋白样蛋白组成。通过尺寸排阻色谱法和纳米差示扫描量热法证实，可溶性提取物处于天然结构状态，与商业提取物不同。在可溶性提取物的圆二色性光谱和总蛋白傅里叶变换红外光谱中酰胺 I 区域（1700-1600 cm）的解卷积中，可以明显看出二级结构的进一步差异。
