Comparison of liquid and gas chromatography for analysis of low molecular weight organic acids in rhizosphere soil

• Published in: Communications in soil science and plant analysis Vol. 28; no. 1/2; pp. 99 - 111
• Main Authors: Sznigielska, A.M. (University of Saskatchewan, Saskatoon, SK, Canada.), Van Rees, K.C.J, Cieslinski, G, Huang, P.M
• Format: Journal Article
• Language: English
• Published: Philadelphia, PA Taylor & Francis Group 1997; Taylor & Francis
• Subjects: ACIDE ORGANIQUE; ACIDOS ORGANICOS; Agronomy. Soil science and plant productions; ANALISIS CUANTITATIVO; ANALISIS DEL SUELO; ANALYSE DE SOL; ANALYSE QUANTITATIVE; Biological and medical sciences; Chemical, physicochemical, biochemical and biological properties; CHROMATOGRAPHIE EN PHASE GAZEUSE; CROMATOGRAFIA DE GASES; Earth sciences; Earth, ocean, space; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; Geochemistry; HPLC; IDENTIFICACION; IDENTIFICATION; MATERIA ORGANICA DEL SUELO; MATIERE ORGANIQUE DU SOL; MEDICION; MESURE; Organic matter; PESO MOLECULAR; Physics, chemistry, biochemistry and biology of agricultural and forest soils; POIDS MOLECULAIRE; RHIZOSPHERE; RIZOSFERA; Soil and rock geochemistry; Soil science; Soils; Surficial geology; Canada; Saskatchewan; North America; America; Monocotyledones; Triticum durum; Cultivated soil; HPLC chromatography; Chernozem; Cereal crop; Organic acids; Molecular weight; Luvisols; Gramineae; Angiospermae; Soil science; Qualitative analysis; Physicochemical method; Quantitative analysis; Method study; Analytical chemistry; Soil chemistry; Liquid chromatography; Organic analysis; Organic chemistry; Gas chromatography; Rhizosphere; Analysis method; Low; Soil analysis; Spermatophyta; Soil plant relation; Comparative study
• ISSN: 0010-3624; 1532-2416
• DOI: 10.1080/00103629709369775

Low molecular weight organic acids from rhizosphere soil of durum wheat (Triticum turgidum var. durum L.) were studied by ion exclusion high pressure liquid chromatography (HPLC) and gas chromatography (GC). Ion exclusion HPLC was found unsatisfactory for acid determination because poor peak resolution hindered acid identification, strongly ionized solutes and oxalic acid co-eluted in the dead volume of the column, and UV detection was not sensitive for aliphatic acid determination. Excellent resolution was obtained when the same low molecular weight organic acids were analyzed by GC. Non-volatile low molecular weight organic acids were separated as trimethylsilyl (TMS) derivatives while volatile acids were analyzed without sample derivatization. A combination of these two GC techniques allowed for separation of 16 acids. Ten low molecular weight organic acids were identified and quantified in rhizosphere soil of durum wheat grown in three different soils. Succinic and acetic acids were most abundant among acids extracted from rhizosphere soils followed by butyric, malic, propionic and tartaric acids. Malonic, fumaric, citric, and trans-aconitic acids were found at the lowest concentrations. Very good resolution, short analysis time, and low detection limits make the GC method very suitable for routine determinations of low molecular organic acids in rhizosphere soil