The phenolic constituents of Prunus domestica. II.—The analysis of tissues of the Victoria plum tree

Abstract

AbstractThe tissues of the Victoria plum tree (Prunus domestica var. Victoria) were analysed for total phenols, leuco‐anthocyanins and flavanols at intervals during the growing season. At all times, the methanol extracts from the smaller leaves contained smaller amounts of phenolic constituents although the changes paralleled those in the larger leaves. The proportions of leuco‐anthocyanins and flavanols to total phenols were less in the smaller leaves. The amounts of the three phenolic constituents increased rapidly until the leaves reached maximum size and then decreased. Leaves taken from the shady side of the tree contained less phenolic constituents and a lower proportion of leuco‐anthocyanins. The analysis of shaded leaves suggested that the synthesis and metabolism of leuco‐anthocyanins were influenced by light. Leaves from unhealthy trees contained smaller amounts of phenolic constituents and the leuco‐anthocyanins were a much smaller fraction. The amount of the phenols in a plum fruit increased with its growth and the Zeuco‐anthocyanins in the skin decreased when it reddened. The phenolic constituents in the woody tissues showed a much smaller variation than the leaves, and the outer bark, phloem and cambium contained more of them than the outer and inner sapwoods and the heartwood.