CHAPTER V 



THE ISOLATION AND CONSTITUTION OF ANTHOCYANINS 



Several general and rather vague views have been held as to the 

 constitution of anthocyanin, without any particular experimental 

 evidence. Thus Wigand (136) believed these pigments to arise by 

 oxidation from a colourless tannin-like chromogen; Overton (333) 

 considered them to be tannin-like substances combined with sugar, 

 and Katie (354), too, found that anthocyanin gave the reactions of a 

 tannin. Palladia (203), again recognised in anthocyanin a respiratory 

 pigment, and yet other suggestions have been advanced by Filhol, 

 Mirande and Combes. 



But in the following cases, definite isolation of the pigments has 

 been attempted, and analyses have been made; the methods and 

 results, however, are so varied that a separate account is essential 

 in each case. We may enumerate the cases thus : 



1849. Morot (122). The flower-pigment of Cento-urea Cyanus. 



1858. Glenard (129, 130). The colouring matter of wine. 



1877. Church (147). The pigment from leaves of Coleus. 



1877. Senier (148). The flower-pigment of Rosa gaUica. 



1878. Gautier (149). The colouring matter of wine. 

 1889. Heise (167). The colouring matter of grapes. 

 1892. Gautier (175). The pigment from red Vine leaves. 

 1892. Glan (176). The flower-pigment of Althaea rosea. 

 1894. Heise (178). The pigment from fruits of the Bilberry. 

 1903. Griffiths (191). The flower- pigment of Pelargonium. 



1906 and 1909. Grafe (197, 209). The flower-pigment of Althaea rosea. 



1911. Grafe (222). The flower-pigment of Pelargonium. 



1913 and 1914. Wheldale (244, 254). The flower-pigment of Antirrhinum majus. 



1913. Willstatter (245). The flower-pigment of Centaurea Cyanus. 



1914. Willstatter (256, 257). The flower-pigment of Delphinium. 



Hollyhock (Althaea rosea). 



Mallow. 



Pelargonium. 



Rosa gaUica. 



The pigment from fruits of the Bilberry. 



,, ,, ,, Cranberry. 



from grapes. 





