Proanthocyanidins of barley and sorghum; composition as a function of maturity of barley ears

Sorghum vulgare seeds contain a proanthocyanidin polymer consisting largely of 2,3-cis procyanidin units with M?_n, 2500. Hordeum vulgare ears contain low levels of proanthocyanidin oligomers containing 2–4 units, and composed largely of 2,3-trans procyanidin and prodelphinidin units with catechin as the terminal unit. The concentration of the oligomers in barley ears was virtually constant throughout the 33 day growth and ripening period.