β-Conglycinin, a major protein in soybeans, shows improvement effect of lipid metabolism. Moreover, this protein influences the processing properties of soybeans. β-Conglycinin is a hetero-trimer constituted by α, α’, and β subunits. In this work, a method for the selective quantification of these subunits was developed by means of protein absolute quantification (AQUA) technology using liquid chromatography/tandem mass spectrometry with the stable isotope-labelled internal standard peptides LQSGDALR[¹³C₆,¹⁵N₄], NILEASYDTK[¹³C₆,¹⁵N₂], and NPIYSNNFGK[¹³C₆,¹⁵N₂]. This method exhibited linear relationships (r² > 0.99) in the concentration range of 1.2–300 fmol/μL for LQSGDALR[¹³C₆,¹⁵N₄] and NILEASYDTK[¹³C₆,¹⁵N₂], and of 4.7–300 fmol/μL for NPIYSNNFGK[¹³C₆,¹⁵N₂]. As a result, the content of these subunits in β-conglycinin-rich and both α and α’ subunit-deficient soybean cultivars was successfully determined. This quantitative assay is promising for the evaluation of the food functionality and processing properties of soybeans.

β-伴大豆球蛋白是大豆中的主要蛋白质，具有改善脂质代谢的作用。而且，该蛋白质影响大豆的加工性能。β-伴大豆球蛋白是由α，α'和β亚基构成的杂三聚体。在这项工作中，这些亚单位的选择性定量的方法是通过使用液相色谱/串联质谱与稳定同位素标记的内标肽LQSGDALR [蛋白质绝对定量（AQUA）技术的装置显影¹³ Ç ₆，¹⁵ Ñ ₄ ]，NILEASYDTK [ ¹³ ç ₆，¹⁵ ñ ₂ ]和NPIYSNNFGK [ ¹³ ç ₆，¹⁵N ₂ ]。这种方法表现出的线性关系（- [R ² 在1.2-300飞摩尔的浓度范围> 0.99）/μL用于LQSGDALR [ ¹³ Ç ₆，¹⁵ Ñ ₄ ]和NILEASYDTK [ ¹³ Ç ₆，¹⁵ Ñ ₂ ]，和4.7-300飞摩尔/μL为NPIYSNNFGK [ ¹³ ç ₆，¹⁵ ñ ₂]。结果，成功确定了富含β-伴大豆球蛋白的α亚基和α'亚基缺失的大豆品种中这些亚基的含量。这种定量分析有望用于评估大豆的食品功能和加工性能。