Department of Conversion Technologies of Biobased Resources, Institute of Agricultural Engineering, University of Hohenheim, Garbenstrasse 9, 70599 Stuttgart, Germany.
Molecules. 2020 Jan 23;25(3):488. doi: 10.3390/molecules25030488.
This study selected three representative protein-rich biomass-brewer's spent grain (BSG), pasture grass (PG), and cyanobacteria (; AP) for protein extraction with different extraction methods (alkaline treatment, aqueous extraction, and subcritical water extraction). The yield, purity, molecular weight, oil-water interfacial tension, and thermal stability of the obtained proteins derived from different biomass and extraction methods were comprehensively characterized and compared. In the view of protein yield and purity, alkaline treatment was found optimal for BSG (21.4 and 60.2 wt.%, respectively) and AP (55.5 and 68.8 wt.%, respectively). With the decreased oil-water interfacial tension, the proteins from all biomass showed the potential to be emulsifier. BSG and AP protein obtained with chemical treatment presented excellent thermal stability. As a novel method, subcritical water extraction is promising in recovering protein from all three biomass with the comparable yield and purity as alkaline treatment. Furthermore, the hydrolyzed protein with lower molecular weight by subcritical water could promote its functions of foaming and emulsifying.
本研究选择三种具有代表性的高蛋白生物质——啤酒糟（BSG）、牧草（PG）和蓝藻（AP），分别采用碱性处理、水提取和亚临界水提取三种方法提取蛋白质，对不同生物质和提取方法得到的蛋白质的产率、纯度、分子量、油水界面张力和热稳定性进行了综合表征和比较。从蛋白质产率和纯度来看，碱性处理对 BSG（分别为 21.4%和 60.2%）和 AP（分别为 55.5%和 68.8%）最为适用。随着油水界面张力的降低，所有生物质来源的蛋白质都表现出作为乳化剂的潜力。经过化学处理得到的 BSG 和 AP 蛋白质表现出优异的热稳定性。作为一种新方法，亚临界水提取有望从三种生物质中以与碱性处理相当的产率和纯度回收蛋白质。此外，亚临界水提取得到的水解蛋白质具有较低的分子量，可促进其发泡和乳化功能。
