Relationship between GC/EI-qMS disaccharide profiles and corresponding genomes of wheat, rye and triticale cultivars

Abstract

Cultivars of small grain species: wheat (Triticum aestivum), rye (Secale cereale) and triticale (Triticosecale) were selected because of their specific biochemical composition of carbohydrates for gas chromatographic analysis. Samples were grounded to flour and extracted with 96% ethanol solution. Extracted mono- and disaccharides were first derivatized into corresponding trimethylsilyl-oximes (TMSO) and analyzed on a GC/EI-qMS device. Four eluting peaks at specific retention times (18.57 min, 18.80 min, 20.85 min, and 21.39 min), were identified as trimethylsilyl-oximes of turanose, melibiose and two peaks of sucrose using Wiley 275 and NIST 14 mass spectra libraries, and were further selected as discrimination factors. Their presence/absence in certain small grain cultivar was labeled with 1/0 thus creating binary numerical matrices, introduced into multivariate analysis. Exploratory data analysis techniques were applied, thus providing a successful background for wheat, rye and triticale species differentiation, regardless of the specific cultivar they belong to, avoiding quantitative determinations of defined discrimination markers. Higher similarities between wheat and triticale cultivars, in comparison with rye species, may be due to the fact that most of the triticale genome structure originates from wheat species.

Keywords

• Triticum aestivum
• Secale cereale
• Triticosecale
• TMSO derivatives
• GC/EI-qMS
• disaccharides
• multivariate analysis