Total phenolics and individual phenolic acids vary with light environment inLindera benzoin

Abstract

The understory shrub Lindera benzoin L. experiences lower rates of herbivory in sun environments than in shade environments. The production of secondary metabolites (e.g., phenolic compounds with known plant defense properties) is one likely contributor to these observed differences in herbivory. This work determined the total phenolic content as well as the concentrations of several individual phenolic acids in L. benzoin leaves found in sun and shade habitats. Total phenolic concentrations were determined to be higher in leaves from sun plants than in those from shade plants (47.5 ± 2.4 vs. 28.6 ± 1.3 gallic acid equivalents, respectively). High-performance liquid chromatography with diode array detection was used to separate and quantify several individual phenolic acids, and specific compounds were identified based on their retention times and ultraviolet spectra. The concentrations of vanillic, chlorogenic, p-coumaric, and ferulic acids were shown to be statistically higher in leaves from sun plants than in those from shade plants (P < 0.05), whereas 2,5-dihydroxybenzoic acid and caffeic acid were not significantly different in L. benzoin leaves from sun versus shade habitats.