MASS-SPECTROMETRIC ANALYSIS OF N-ACETYLCHITOOLIGOSACCHARIDES PREPAREDTHROUGH ENZYMATIC-HYDROLYSIS OF CHITOSAN

A semipreparative scale chromatography of N-acetylchitooligosaccharide s (GlcNAc)(2-7) on a reversed-phase C-16 HPLC column is reported. The initial material was obtained by enzymatic hydrolysis of chitosan with a complex of chitinases from Streptomyces kurssanovii, followed by a complete acetylation of amino groups. Isolated N-acetylchitooligosacch arides were characterized by the mass-spectrometric method. On interac ting with the sample, the fragments of Cf-252 caused desorption of qua si-molecular ions of the substance. All mass spectra of chitin oligome rs contained intense quasi-molecular ions [M + Na](+) and a less inten se [M + K](+) ion. Fragment ions, compared to the quasi-molecular ion [M + K](+), had a Lower intensity and confirmed the structure of sampl es under study. Due to this phenomenon, an accurate analysis of both i ndividual compounds and mixtures of N-acetylchitooligosaccharides (n = 2-7) may be performed. (C) 1995 Academic Press, Inc.