Détermination quantitative des acides organiques dans les extraits végétaux : Amélioration de la technique d'analyse par chromatographie de partage sur colonne de gel de silice

Abstract Quantitative determination of organic acids in plant extracts. Improvement in the analysis by partition chromatography on a silica gel column The organic acids extracted from plant tissue are separated in two groups by passage over an anionic resin column, Amberlite IRA-400. The first group, eluted by means of a 0.9% aqueous solution of ammonium carbonate, includes the monocarboxylic acids pyrrolidonecarboxylic, glycolic, and glyceric; the second, eluted by means of a 6% aqueous solution of ammonium carbonate, comprises the dicarboxylic acids mesaconic, fumaric, succinic, malonic, oxalic, malic, and tartaric and the tricarboxylic acids cis - and trans -aconitic, citric and isocitric. The organic acids of each group are then automatically separated by partition chromatography on a silica gel column using as eluant for the first group a solvent containing chloroform and for the second a solvent containing chloroform and cyclohexane. The organic acids once eluted are determined by spectrophotometry in the presence of o -nitrophenol sodium salt.