In Ukrainian

Abstract

The results are presented of a study on spectral characteristics, electron microscopy data and antibacterial properties of Lactobacillus plantarum cell matrices filled with biologically synthesized in the presence of surfactants (S) silver nanoparticles (bioAgNP). The dependences of spectral characteristic of cell suspension of lactic acid bacteria L.plantarum with synthesized bioAgNP on S concentration were analyzed, namely: cationic two quaternary ammonium salt (CS) aethonium and anionic sodium decyl phosphate (AS). To control the process of bioAgNP production in microorganism cells, the method of spectroscopy in ultraviolet and visible regions was used. The antibacterial properties of modified L. plantarum cells dependent on synthesis condition and their composition were testified by disco diffusion method. The results are presented of electron-microscopy investigation of treated with concentrated sulfuric acid bionanocomposite material. It is shown that addition at the synthesis of an ionogenic S to the precursor solution affects structural and size descriptions of biogenic silver formed in L. plantarum cells. Since a concentration more then the critical concentration of micelle formation, aethonium presence resulted in forming of two NPs fractions, namely: stabilized in a cell wall subcolloidal particles having absorption band at 380 nm and also aggregated particles having spectral shoulder at 440 nm. S addition promoted the red shift of absorption spectra dependent on CS concentration and medium pH, however not dependent on AS concentration. It is shown that antibacterial properties of modified with S nanobiocomposite materials mainly depend on the NPs content in lactic acid matrices and on their size. Joint application of bionanocomposite and aethonium preparation close to the critical micelle concentration allowed to rise their activity in relation to Gram(+)bacteria and, at the same time, to bring down on an order (from 1.0 to 0.1 %) the ordinary therapeutic dose of aethonium.