Identification and quantitative analysis of cytokinins from shoot apices of Mercurialis ambigua by gas chromatography-Mass spectrometry computer system.

This paper describes the identification and quantitative analysis of cytokinins from natural sources (150-500 g fresh weight) at the submicrogram level. It summarizes an improved purification procedure with high resolution power that permits the detection of Trimethylsilylderivatives by gas chromatography-mass spectrometry. A comparison of the intensity of a characteristic ion in the mass spectrum of suitable standard (5 μg) and theintensity of the same ion in the mass spectrum of the extraction product permitted precise quantitative analysis. The method has been used to determine zeatin, trans- and cis-ribosylzeatin, and Δ(2)-isopentenyladenosine concentrations in extracts from female and monoecious Mercurialis ambigua apices. It has been proved that differences appear in the endogenous cytokinin pools of monoecious and female individuals.