Phacelia campanularia

The actual explanation was given as a result of marty years of research. The pH of 4-6 in the vacuoles of plants would be consistent with the colorless pseudobase form of anthocyanins or a little bit of the violet anl drobase. This pseudobase, on the other hand, is understood to be rare in Nature. In addition to pH, the interactions of anthocyanins with each other, other polyphenol type pigments (such as flavonoids or flavons), and metal ions such as alirminum, gallium and iron(in) collectively determine the color. Desert bluebells Phacelia campanularia) are true to their name as their flowers are blue, which is caused by aggregation between phacelianin molecules and their interaction with aluminum(III) and iron(III) ions. 

Mori A, Lehmann S, O KeUy J, Kumagai T, Desmond JC, Pervan M, McBride WH, Kizaki M, Koeffler HP (2006) Capsaicin, a component of red peppers, inhibits the growth of androgen-independent, p53 prostate cancer cells. Cancer Res 66 3222-3229 Mori M, Kondo T, Told K, Yoshida K (2006) Structure of anthocyanin from the blue petals of Phacelia campanularia and its blue flower color development. Phytochemistry 67 622-629 Morikawa T, Xu F, Matsuda H, Yoshikawa M (2006) Structures of new flavonoids, erycibenins D, E, and F, and NO production inhibitors from Erycibe expansa originating in Thailand. Chem PharmBuU 54 1530-1534... 

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