Phenol conjugation with phosphate

Figure 5. Conjugation of xenobiotic phenols with phosphate.

Tiburzy (22,31) obtained similar results by application of the PAL inhibitor aminooxyacetic acid (AOA). However, AOA does not specifically inhibit PAL (99), and PAL is not only involved in lignin biosynthesis (100). Thus, AOA and the related inhibitor aminooxyphenyl propionic acid (AOPP) (101,102) inhibit the biosynthesis of lignin (103,104), anthocyanins (105), other flavonoids (106), and conjugates of cinnamic acids (107) via PAL, as well as ethylene (108-110) via a pyridoxal phosphate dependent enzyme (110,111). In view of the possible function of phenolic compounds as phytoalexins (21,112,113) and the well documented role of ethylene in some resistance reactions (114-116), the above cited experiments with AOA (22,... 

Other anionic surfactants, such as nonyl phenol ethoxy phosphate (commercial term) with an aromatic structure, also absorbs in the UV range at 225 nm. Nonyl phenol ethoxy phosphate has two absorption bands (225 nm, 275 nm). The presence of two aromatic rings in the molecular structure of alkyl diphenyloxide disulphonate (commercial term) leads to a bathochromic shift due to an extended conjugation in molecule. In this case, the absorption band is observed at 237 nm. 

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