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The hydrogels based on nanocomposite pectin-Ag exhibiting the antibacterial activity (MIСAg = 0.02–0.81 mM) were obtained by ionotropic gelation. It was shown that the synthesized hydrogels had a high capacity for kanamycin (up to 70 wt. %). The obtained hydrogels provided a prolonged release of kanamycin in 0.9 % NaCl and enhanced its antibacterial activity (MIC decreased 10–20 times) due to the synergistic effect.

Pectin‐Ag nanocomposites with a core‐shell structure are synthesized by the “green chemistry” method based on the reduction of silver nitrate with pectin (amidated, low‐, or high methoxylated) in an alkaline medium at room temperature. TEM and DLS measurements show that the average size of the inorganic core (10–30 nm) and hydrodynamic diameter of the nanocomposite (284.8–649.2 nm) depend on the type of pectin. The films based on pectin‐Ag nanocomposites and polyvinyl alcohol (PVA) with different molecular weight (30, 66, and 145 kDa) are obtained by casting evaporation technique. A comparative study of their mechanical, optical, degradation and antibacterial properties is carried out. The films with the smaller size of Ag nanocomposite exhibit higher antimicrobial activity against Bacillus strains. The pectin‐Ag/PVA films are loaded with antibiotic kanamycin (KAN). Prolonged release of antibiotic and pronounced (up to full inhibition) antimicrobial effect of pectin‐Ag/PVA/KAN films against Escherichia coli, Pseudomonas aeruginosa, Bacillus pumilus, and Bacillus subtilis is due to the formation of pectin‐Ag/KAN complexes. Moreover, pectin‐Ag/PVA/KAN films show high potency against resistant strains Pseudomonas aeruginosa. The obtained multifunctional films are expected to find promising applications in biomedical engineering and wound healing.

Background: Nonpathogenic Bacillus strains are used in biotechnology, and pathogenic Bacillus strains are cause of food borne disease. It explains the relevance of the methods of detection and quantification of whole cell and cell components of these bacteria. Aims: Development of methodological approach for investigation of dynamics of specific concentration of cell wall antigens per cell of bacilli without solubilization of cell wall during sample preparation; using of the approach with 6 strains of bacilli as an example. Method: ELISA. Results: Methodological approach for investigation of dynamics of specific concentration of bacilli cell wall antigens has been developed. The distinctive features of the approach are rabbit polyclonal antibodies to genera-specific antigens of bacilli as key reagent and lack of need for solubilization of cell wall during sample preparation. It was shown using 6 strains of Bacilli as an example that specific concentration of cell wall antigens per cell vary according to bacillus strain, stage of culture growth and media composition. The data will find an application in biotechnology of clinical diagnostics and test-systems for food control including detection of whole bacillus cells.