Light-induced increase in the contents of ferulic and diferulic acids in cell walls of Avena coleoptiles: its relationship to growth inhibition by light |
| |
Authors: | Kensuke Miyamoto Junichi Ueda Satomi Takeda Kazuko Ida Takayuki Hoson Yoshio Masuda Seiichiro Kamisaka |
| |
Affiliation: | College of Integrated Arts and Sciences, Univ. of Osaka Prefecture, 1-1 Gakuen-cho, Sakai 593, Osaka, Japan.;Dept of Natural Science, Osaka Women's Univ., Daisen-cho, Sakai 591, Osaka, Japan.;Dept of Biology, Fac. of Science, Osaka City Univ., Sumiyoshi-ku, Osaka 558, Japan.;Food Science Laboratory, Tezukayama College, Gakuenminami, Nara 631, Japan. |
| |
Abstract: | White fluorescent light (5 W m−2) inhibited Avena coleoptile growth. Light caused in increase in minimum stress relaxation time and a decrease in extensibility (strain/load) of coleoptile cell walls. Light increased the contents of ferulic acid (FA) and diferulic acid (DFA) ester-linked to the hemicellulose I in cell walls. These changes in the phenolic contents correlated with those of the mechanical properties of cell walls, suggesting that light stimulates the formation of DFA in hemicellulose I, making cell walls rigid, and thus results in growth inhibition. The ratio of DFA to FA was almost constant in the dark, but decreased in light, although it was almost constant in Oryza coleoptiles either in the dark or in light (Tan et al. 1992). From this fact, it is speculated that in the light condition, the formation of DFA in cell walls is limited in the step of the peroxidase catalyzed coupling reaction to produce DFA, while in the dark it is limited in the step of the feruloylation of hemicellulose I. |
| |
Keywords: | Avena sativa cell wall cell wall extensibility coleoptile diferulic acid ferulic acid growth inhibition light, oat |
|
|