Proteins in Oats; their Synthesis and Changes during Germination: A Review

Abstract

Oats (Avena sativa L.) are distinct among cereals due to their considerably higher protein concentration. At the same time oats possess a protein quality of high nutritional value and a special protein composition. Most cereals like wheat, barley, and rye have a high percentage of prolamins, the alcohol-soluble fraction, which usually contains most of the storage proteins, but oats are an exception. Their major storage proteins belong to the salt-water soluble globulin fraction, whereas oats prolamins are a minor component. During oats groat development, most obvious is the fairly linear increase in the globulin fraction. Oats globulins share structural features with the 11 S globulins of legumes and other dicots. Amino acid composition of oats is superior to that of other cereals due to the higher amount of limiting amino acids like lysine and threonine. During germination, total amino acid analysis revealed an increase in essential amino acids like lysine and tryptophan, which leads to an increased nutritional value of germinated oats. Oats protein products including globulin have been chemically modified by various methods to improve their functional properties.

Heterosis and genetic parameters for grain quality in oat segregating populations

“…It presents high digestibility and a balanced amino acid composition (Biel et al, 2014;Doehlert et al, 2013;Hawerroth et al, 2013;Klose and Arendt, 2012). For the PROT content, an absence in heterosis gain in both populations was observed (Table 1), which can be an indicative of low combining ability between the parents, possibly due to the presence of similar loci that expresses reduced average performance for the trait, even after genetic recombination.…”

Emulsion gels as potential fat replacers delivering β-glucan and healthy lipid content for food applications

“…Their low prolamine content (4-15%) makes them suitable for inclusion in glutenfree diets (Storsrud et al 2003). Compared to other cereal proteins, oat protein also provides a better amino acid balance as it contains higher amounts of limiting amino acids lysine and threonine, which are essential for humans and other monogastric animals (Klose and Arendt 2012).…”

“…Oat bran proteins consist mainly of globulins, although they also contain smaller proportions of albumins, glutelins and prolamines (Klose and Arendt 2012). Their low prolamine content (4-15%) makes them suitable for inclusion in glutenfree diets (Storsrud et al 2003).…”

The use of UniProtKB/BIOPEP for the analysis of oat globulin physicochemical parameters and bioactivity

“…The parameters can be used in preliminary identification of oat proteins separated, for example, by the 2-DE technique, applied commonly in proteomic studies. This technique was used to separate prolamins of oats, and 13 spots (MW(s) range 27-34.6 kDa, pI(s) 5.7-7.6) were considered to be the most typical of this protein fraction, whereas the calculated (theoretical) numerical ranges of parameters for 41 sequences of avenins, gliadin-like avenins and their fragments were MW(s) 20.41-32.79 kDa and pI(s) 5.56-8.97 (Klose & Arendt 2012;Szerszunowicz et al 2017).…”

“…This study used oat globulins due to their dominating presence in grain (they account for 50-80% of total protein), as well as to the beneficial amino acid composition of the proteins and lower content of prolamins (4-15% of total protein), regarded as coeliac-toxic (Klose & Arendt 2012).…”