Variability in the total and component galactosyl sucrose oligosaccharides of Lupinus species

Abstract

The oligosaccharide compositions of 33 lupin seed accessions and cultivars, from 10 species, are reported. Seed weights varied from 3.8 to 66.6 g/100 seeds. Total oligosaccharide content ranged from just under lo%, to almost 23% dry matter. In all cases the quantity of oligosaccharides (raffinose, stachyose and verbascose) was higher than that of disacharides (sucrose and melibiose). Verbascose ranged from 0.0 to 33.4% of total oligosaccharide content, and raffinose from 4.7 to 47.4%. Stachyose was the predominant and most constant sugar in majority of the seeds examined, the highest level (75%) being recorded in one line of L. hispanicus. The amounts of stachyose and verbascose, which are considered to be of major importance as 'flatus factors', were higher than those recorded for most established legume crops, although considerable variation was found between lupin species and some within a lupin species. Sufficient variability appears to be present within L. angustifolius in total oligosaccharides, and to a smaller extent in component saccharides [other than that apparently associated with existing domestication gene(s)] to warrant selection for improved saccharide composition as part of the breeding process.