p-coumaric acid ? a monomer in the sporopollenin skeleton

Abstract

147ness after blue light (not shown). This shows that energy and metabolites were not completely absent. However, as hair-whorl formation was undetectable (with the exception of dwl), this could mean that the transition to the development of whorls only proceeded when the level of photosynthetic metabolites was higher than the minimum required for stalk growth alone. The different requirements for red irradiation among the different strains would then reflect different levels of metabolite availability. Similar differences in the light requirement for stalk growth and cap formation were observed with Acetabularia erenulata grown in white light of various irradiances (Terborgh and Thimann 1965).The metabolites must be available and produced at the tip itself since local irradiation of Acetabularia cells has shown that growth can proceed only when the cells receive light at the apex rather than at the base (Gibor 1977). Apical or basal applications of DCMU also prevented growth only when the tip was treated, indicating that at least part of these effects were due to photosynthesis. Metabolites and DCMU do not appear to be transported longitudinally.References Clauss, H. (1968) Planta (1989) 179:376-380 Page 377: The intensity of m/z 164 indicates that the compound is bound by its acid group in the sample because ester-bound p-coumaric acid decarboxylates during pyrolysis to vinylphenol (Boon 1989).The corrected text: The intensity of m/z 164 indicates that the compound is not bound by its acid group in the sample because ester-bound p-coumaric acid decarboxylates during pyrolysis to vinylphenol (Boon 1989).

Analytical in source pyrolytic methylation electron impact mass spectrometry of phenolic acids in biological matrices

“…Pollen wings of Pinus contain sporopollenin which comprises p-coumaric acid (Wehling et al, 1989). In order to investigate whether TMAH would show a similar effect on p-coumaric acid embedded in a more complex matrix of biological origin, this material was used for Py-MS under 16 eV E I conditions.…”

“…These acids can be bound with an ether bond (through the hydroxyl group on the ring) or an ester bond (through the carboxyl group). Under EI conditions, the phenolic acids p-coumaric acid (MW 164) and ferulic acid (MW 194) show the molecular ions and their decarboxylated fragments at mlz 120 (vinylphenol) and m/z 150 (vinylguaiacol), respectively (Mulder et al, 1991a;Wehling et al, 1989). Decarboxylation occurs in free phenolic acids or in ester-bound compounds.…”

“…However, the same compounds are found as pyrolysis products from the related alcohols. Under EI ionization conditions the molecular ion of phenolic acids is observed in the mass spectra if ether bound (Wehling et al, 1989).…”

Pyrolysis mass spectrometry of developmental stages of maize somatic embryos

“…The accumulation of ferulic acid in cell walls of cell-suspension cultures is not unusual and was also observed in a culture of Chenopodium rubrum L. (Bokern et al 1991). The relatively high abundance of mass peak 150 compared to 194 suggests a high degree of esterification to polysaccharides of these compounds (Wehling et al 1989;Mulder et al 1992; Morrison & Mulder, unpublished results). Previously, it was shown that esterified phenolic acids easily decarboxylate resulting in 4-vinylphenol (m/z 120) (from p-coumaric acid) or 4-viny1guaiacol (m/z 150) (from ferulic aid) (Wehling et al 1989).…”

“…Using analytical pyrolysis mass spectrometry (PyMS), fingerprint information of various component classes of a small, solid sample can be obtained. This technique has been shown to provide a means of mapping (bio)molecules such as (poly)phenols and polysaccharides in biological material (Boon 1989;. PyMS is based on flash heating of a sample, leading to a volatilization of smaller units.…”