Nynäs Anna-Lovisa, Newson William R, Johansson Eva
Department of Plant Breeding, Swedish University of Agricultural Sciences, P.O. Box 190, SE-23422 Lomma, Sweden.
Foods. 2021 Oct 21;10(11):2533. doi: 10.3390/foods10112533.
Green biomass has potential as a sustainable protein source for human consumption, due to its abundance and favorable properties of its main protein, RuBisCO. Here, protein fractionation outcomes of green leafy biomass from nine crops were evaluated using a standard protocol with three major steps: juicing, thermal precipitation, and acid precipitation. Successful protein fractionation, with a freeze-dried, resolubilized white protein isolate containing RuBisCO as the final fraction, was achieved for seven of the crops, although the amount and quality of the resulting fractions differed considerably between crops. Biomass structure was negatively correlated with successful fractionation of proteins from biomass to green juice. The proteins in carrot and cabbage leaves were strongly associated with particles in the green juice, resulting in unsuccessful fractionation. Differences in thermal stability were correlated with relatedness of the biomass types, e.g., varieties showed similar performance in thermal precipitation. The optimal pH values identified for acid precipitation of soluble leaf proteins were lower than the theoretical value for RuBisCO for all biomass types, but with clear differences between biomass types. These findings reveal the challenges in using one standard fractionation protocol for production of food proteins from all types of green biomass and indicate that a general fractionation procedure where parameters are easily adjusted based on biomass type should instead be developed.
绿色生物质作为一种可持续的人类食用蛋白质来源具有潜力，这归因于其丰富性以及主要蛋白质核酮糖-1,5-二磷酸羧化酶/加氧酶（RuBisCO）的优良特性。在此，采用包含榨汁、热沉淀和酸沉淀三个主要步骤的标准方案，对九种作物的绿叶生物质的蛋白质分级分离结果进行了评估。七种作物实现了成功的蛋白质分级分离，最终级分为含有RuBisCO的冻干、复溶白色蛋白质分离物，尽管不同作物所得级分的数量和质量差异很大。生物质结构与从生物质到绿色汁液的蛋白质成功分级分离呈负相关。胡萝卜叶和卷心菜叶中的蛋白质与绿色汁液中的颗粒紧密相关，导致分级分离失败。热稳定性差异与生物质类型的相关性有关，例如，不同品种在热沉淀中表现出相似的性能。为所有生物质类型的可溶性叶蛋白酸沉淀确定的最佳pH值均低于RuBisCO的理论值，但不同生物质类型之间存在明显差异。这些发现揭示了使用一种标准分级方案从所有类型的绿色生物质生产食品蛋白质所面临的挑战，并表明应开发一种基于生物质类型易于调整参数的通用分级程序。
