Isolation, purification, and characterization of the globulin from wheat germ

Abstract

This research optimized the extraction and purification of globulin from wheat germ and assessed the molecular weight distribution and structure properties of the globulin obtained. The results showed that the relative extraction efficiency and purity of wheat germ globulin (WGG) reached 18.0% and 89.1% under the enzymolysis conditions of 0.32& a-amylase, pH 6.5, and 55 °C. The maximal precipitation rate of WGG (91.3%) was obtained with pH 4.3 (acid precipitation). Additionally, the molecular weight of WGG was mainly distributed below 70 kDa. FT-IR confirmed that random coils (30.95%), b-sheet (27.02%), a-helix (26.55%), and b-turn (15.48%) were the secondary structures of WGG. Furthermore, LTQ mass spectrometry showed that WGG was rich in variety and high in complexity, which retrieved 1274 proteins belonging to 392 proteomes by inverse peptide analysis. The findings endow a great potential of preparing WGG with superior functionality for food applications.

Possibility of using wheat germ and wheat germ protein isolate for high‐protein pasta production

“…To extend this storage time, it seems expedient to isolate the protein from wheat germ. It has been reported that it is possible to obtain protein isolate from wheat germ at a yield of over 90% (Fan et al, 2022; Hettiarachchy et al, 1996), which can make it possible to increase the content of this macronutrient in final products.…”