Development of arabinans and galactans during the maturation of hypocotyl cells of mung bean (Vigna radiata Wilczek)

Hypocotyl cell walls contain galactans and arabinans that are soluble in boiling water. During maturation, the Ara/Gal ratio remains unchanged but high-molecular-weight galactans are replaced by smaller polymers. On the basis of the ¹H-n.m.r. 2D-COSY(δ-δ, ¹H-¹H)n.m.r., and ¹³C-n.m.r. spectra, a (1→5)-α-Araf structure can be proposed for the arabinans in both young and nature cell walls. However, the galanctan(s) changed from a probably highly branched to an unbranched (1→4)-β-Galp structure during maturation.