Estimation of the sulfate content of hydrothermal vent bacterial polysaccharides by Fourier transform infrared spectroscopy.

Deep-sea hydrothermal vents are characterized by unusual chemical and physical parameters, including high pressure and temperature. In this extreme environment, unusual microorganisms of biotechnological importance survive. Polymer-producing bacteria have been specifically studied for several years with the aim of demonstrating their ability to produce unusual polysaccharides in terms of physical, chemical, and biological properties. Because sulfates play an important role in the biological properties of polysaccharides, it is very important to determine their content with accuracy. Fourier transform infrared spectroscopy (FT-IR) was used for sulfate analysis and the results were compared with those of other analytical techniques. We found a good correlation between FT-IR and other analytical techniques for sulfate concentrations ranging from 2.4 to 20%. The data indicated that this technique could be used to determine the chemical composition of the polymers along with a semiquantitative estimation of the sulfate content.