Natural Proanthocyanidins

Abstract

The formation of red colours from colourless materials present in the leaves, fruit and flowers of many higher plants has long been known and not surprisingly some uncertainty exists as to who first demonstrated this distinctive property. The chemical and bio- chemical literature show that Staats (1895), Laborde (1908), Tswett (1914) and Willstätter and Nolan (1915) all reported experimental observations of this type during the same period at the beginning of this century but Pigman and his associates (1953) credit Robert Boyle with the first recorded example of this property some sixty years earlier.