Enzymatic fingerprinting of arabinoxylan and β-glucan in triticale, barley and tritordeum grains

• Published in: Carbohydrate polymers 2012-10, Vol.90 (3), p.1226-1234
• Main Authors: Rakha, A., Saulnier, L., Åman, P., Andersson, R.
• Format: Article
• Language: English
• Subjects: Applied sciences; Arabinoxylan; Barley; beta-glucans; beta-Glucans - analysis; beta-Glucans - chemistry; Biological and medical sciences; breeding lines; Chemical and Process Engineering; cultivars; Edible Grain - chemistry; Engineering Sciences; Enzymatic fingerprinting; Exact sciences and technology; Food engineering; Food industries; Food Science; Fundamental and applied biological sciences. Psychology; genetic variation; genotype; grain quality; Hordeum - chemistry; licheninase; Life Sciences; Livsmedelsvetenskap; Natural polymers; Oligosaccharides - analysis; Oligosaccharides - chemistry; Physicochemistry of polymers; principal component analysis; Species Specificity; Starch and polysaccharides; Starch and starchy product industries; trisaccharides; Triticale; Tritordeum; whole grain foods; Xylans - analysis; Xylans - chemistry; β-Glucan
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2012.06.054

► We studied structural features of arabinoxylan and β-glucan in triticale, barley and tritordeum by enzymatic fingerprinting. ► Generally, barley and tritordeum had arabinoxylan which generated higher relative proportions of branched fragments than triticale. ► Triticale grown at a location with high rainfall generated a smaller proportion of branched arabinoxylan fragments. ► For β-glucan, barley had a positive correlation between content and DP 3 oligomer. Enzymatic fingerprinting of arabinoxylan (AX) and β-glucan using endo-xylanase and lichenase, respectively, helps determine the structural heterogeneity between different cereals and within genotypes of the same cereal. This study characterised the structural features of AX and β-glucan in whole grains of eight triticale cultivars grown at two locations, 20 barley cultivars/lines with wide variation in composition and morphology and five tritordeum breeding lines. Principal component analysis (PCA) resulted in clear clustering of these cereals. In general, barley and tritordeum had a higher relative proportion of highly branched arabinoxylan oligosaccharides (AXOS) than triticale. Subsequent analysis of triticale revealed two clusters based on growing region along principal component (PC) 1, while PC2 explained the genetic variability and was based on mono-substitution and di-substitution in AX fragments. PCA of β-glucan features separated the three cereals based on β-glucan content. The molar ratio of trisaccharide to tetrasaccharide was 2.5–3.4 in triticale, 2.3–3.3 in barley and 2.8–3.4 in tritordeum. Barley showed a strong positive correlation (r=0.86) between β-glucan content and relative proportion of trisaccharide. The results show that structural features of AX and β-glucan vary between and within triticale, barley and tritordeum grains which might be important determinants of end-use quality of grains.