A proposed structure of commelinin, a sky-blue anthocyanin complex obtained from the flower petals of commelina

✍ Scribed by Toshio Goto; Tsutomu Hoshino; Shigehiro Takase

• Publisher: Elsevier Science
• Year: 1979
• Tongue: French
• Weight: 245 KB
• Volume: 20
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(01)86447-9

✦ Synopsis

Extensive studies on the correlation between structure of anthocyanin and flower color have been carried out, but some important problems still remain unsolved . )

One of them is nature of blue color of flowers such as commelinin . Origin of such blue color cannot be explained simply in terms of pH change of the color of anthocyanins, because not only their long-wave absorption but also their stability in neutral solutions . 1 Shibata in 1918 attempted to explain this stability and color in terms of complex formation of anthocyanin with some metal ions . 2 Indeed, some anthocyanidins are well known to form deep colored complex with ferric or aluminum ion .

Later Robinson 3 suggested that flavones and tannins have stabilization and bluing effects on anthocyanins by co-pigmentation effect . Robinson 3 further suggested that polypeptides and polysaccharides also combine with anthocyanins to produce change of stabilily and color .

Commelinin, which is obtainable from petals of Commelina (Japanese name : tsuyu-kusa), is