New Approaches to Development of Biopreparations of Lactic Acid Bacteria

High rate of cell death with the loss of their consumer and technological properties is a considerable shortcoming of the preparations of lactic acid bacteria (LAB). The goal of the present work was to develop efficient approaches to increased LAB survival during long-term storage. Immobilization of E. faecium cells in gelatin gels (50 and 100 g/L) was shown to result in the preservation of the ultrastructure of vegetative cells after 1–2 months of storage, while lysed cells predominated in planktonic cultures after such period of incubation, and cystlike dormant forms and L-forms were also present. In the gellan gum gel (10 g/L) the cells formed biofilms with a characteristic exopolysaccharide matrix and vesicles, while in the guar gum gel (10 g/L), lysed cells and L-forms without cell wall predominated. The innovative silanol-hymate gel was found to efficiently protect the LAB cells during long-term storage at 4 and 25°C, relative humidity 40, 50, and 99%, under intense illumination, and in the case of free air access. Gel immobilization of LAB cells is a promising method for food industry and various fields of agrobiotechnology.