You are not currently logged in.
Access your personal account or get JSTOR access through your library or other institution:
Colour Reactions of Flowers attributed to (a) Flavanols and (b) Carotenoid Oxides
E. C. BATE-SMITH
Journal of Experimental Botany
Vol. 4, No. 10 (Feb. 1953), pp. 1-9
Published by: Oxford University Press
Stable URL: http://www.jstor.org/stable/23686156
Page Count: 9
Preview not available
1. The petals of many white flowers, when heated with 2N hydrochloric acid, give golden-brown to red-brown colorations, attributable to catechins (yellow-brown) and leuco-anthocyanins (rose to crimson). Extracts of petals which give this reaction give a red colour with vanillin in concentrated HCl, which is consistent with the reaction being due to flavanols. 2. With the exception of two species of Malvaceae, no flowers of herbaceous plants have given this reaction. A majority of flowers of woody plants give the reaction. The limited distribution of flavanols (supposing this identification of the chromogens to be correct) is contrasted with the universal distribution of anthocyanins. 3. The petals of many yellow flowers, when allowed to stand in contact with 1 per cent. methanolic HCl, produce a green coloration attributable to the presence of carotenoid oxides in the petals. Flowers not giving this reaction are limited in their systematic distribution.
Journal of Experimental Botany © 1953 Oxford University Press