Properties of composite systems based on suspensions of lactobacillus and silica

Abstract

Low-temperature 1H NMR spectroscopy and DSC methods were used to study the hydration process of Lactobacillus, the influence of a weakly polar organic environment on it, and the encapsulation of cells with silica and the possibility of penetration of such an active substance as trifluoroacetic acid (TFAA) into them. It is shown that the spectral parameters of water in concentrated cell suspensions of Lactobacillus significantly depend on the concentration of the suspensions, which is probably related to the possibility of forming a stable cell gel, which can be encapsulated by silica particles both in the air environment and in the environment without its destruction chloroform with the addition of trifluoroacetic acid. There are two maxima corresponding to R = 2 and 20-100 nm on the distribution curves of the radii of clusters of unfreezing water. The contribution to the distribution of the second maximum increases with increasing water concentration. On the DSC-thermograms of lactobacilli, the value of the thermal effect related to the amount of bound water is much smaller than the thermal effect of ice melting, which is due to the presence of a significant amount of non-freezing water.