Profiling Secondary Metabolites of Needles of Ozone-Fumigated White Pine (Pinus strobus) Clones by Thermally Assisted Hydrolysis/Methylation GC/MS

• Published in: Journal of chemical ecology Vol. 33; no. 7; pp. 1467 - 1476
• Main Authors: Shadkami, F, Helleur, R. J, Cox, R. M
• Format: Journal Article
• Language: English
• Published: New York, NY New York : Springer-Verlag 01.07.2007; Springer; Springer Nature B.V
• Subjects: Acids; Air pollution; Animal, plant and microbial ecology; Applied ecology; Biological and medical sciences; biological resistance; Biomonitoring; chemical analysis; Chromatography; conifer needles; Dihydroxybenzoic acid; Diterpenes; dose response; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on plants and fungi; Forest productivity; Fumigation; Fundamental and applied biological sciences. Psychology; Gas chromatography; Gas Chromatography-Mass Spectrometry; Herbivores; Hydrolysis; Mass spectrometry; Mass spectroscopy; Metabolites; Methylation; Ozone; Ozone - pharmacology; Phenolic acids; Phenols; Phenotypic variations; Pine; Pine needles; Pine trees; Pinus - chemistry; Pinus strobus; Plant Leaves - chemistry; Pollutants; pollution tolerance; Profiling; resin acids; Resins; Secondary metabolites; Chemical analysis; White pine (Pinus strobus); Phenolic acid; Metabolite; Organism defense; Phenolic acids; Secondary metabolites; Diterpene resin acids; Gymnospermae; Softwood forest tree; Needles; Resins; Clone; Ozone; Hydrolysis; Gas chromatography; Pollutant; Thermally assisted hydrolysis and methylation; Sensitivity resistance; Pinus strobus; Diterpene; Coniferales; Spermatophyta; Methylation; Mass spectrometry; GC/MS
• ISSN: 0098-0331; 1573-1561
• DOI: 10.1007/s10886-007-9314-1

Plant secondary metabolites have an important role in defense responses against herbivores and pathogens, and as a chemical barrier to elevated levels of harmful air pollutants. This study involves the rapid chemical profiling of phenolic and diterpene resin acids in needles of two (ozone-tolerant and ozone-sensitive) white pine (Pinus strobus) clones, fumigated with different ozone levels (control, and daily events peaking at 80 and 200 ppb) for 40 days. The phenolic and resin acids were measured using thermally assisted hydrolysis and methylation (THM) gas chromatography/mass spectrometry. Short-term fumigation affected the levels of two phenolic acids, i.e., 3-hydroxybenzoic and 3,4-dihydroxybenzoic acids, in that both showed a substantial decrease in concentration with increased ozone dose. The decrease in concentration of these THM products may be caused by inhibition of the plant's shikimate biochemical pathway caused by ozone exposure. The combined occurrence of these two ozone-sensitive indicators has a role in biomonitoring of ozone levels and its impact on forest productivity. In addition, chromatographic profile differences in the major diterpene resin acid components were observed between ozone-tolerant and ozone-sensitive clones. The resin acids anticopalic, 3-oxoanticopalic, 3β-hydroxyanticopalic, and 3,4-cycloanticopalic acids were present in the ozone-sensitive pine; however, only anticopalic acid was present in the ozone-tolerant clone. This phenotypic variation in resin acid composition may be useful in distinguishing populations that are differentially adapted to air pollutants.