抄録
In our previous studies, we elucidated the structure of the unstable yellow precursor of carthamin (5). The elucidated structure of 5 suggested that it was biogenetically derived from safflower yellow B (3) in the florets of safflower. The transformation of 3 with cultured safflower cells was investigated to prove this hypothesis. Safflower Yellow B was transformed to red carthamin (1) and safflomin-A (2) in the safflower cells cultured on the Murashige-Skoog medium which lacks NH_4NO_3 and KH_2PO_4. The transfomation of 3 by the crude enzyme extracted from the above safflower cells, gave 2 and 6 in good yields. The compound 6 was unstable and easily converted to precursor (5) by the addition of glyoxylic acid. Actually, a very small amount of glyoxilic acid was detected in the safflower cell. Further, the treatment of 5 with the cell-free homogenate of culltured safflower cells gave 1 quantitatively. From these results, it was confirmed that 1 was biogenetically derived from 3 in the safflower cell by way of compound 6 and 5. Further, it was also confirmed that the treatment of 3 in the concentrated phosphate buffer solution, gave 2 and 6 almost quantitatively. It may be found the convenient method to produce 1 from 3 in the application of this transformation.
