Abstract
A fast, sensitive method for extraction and analysis of soluble free amino acids from microbially colonized sandstone is described. After precolumn phenyl isothiocyanate (PITC) derivatization, the PITC-amino acids were identified and quantified by reversed-phase high-performance liquid chromatography. This kind of analysis could be used to elucidate the role and function of amino acids in the nutrition of epi- and endolithic microorganisms active in biological weathering processes.