To investigate antiviral properties/activity of the PBS and its composites, the Φ6 bacteriophage was prepared according to reports. As a phage host, Pseudomonas syringae was used. To evaluate the host's growth rate in real-time, after its 24 h contact/cultivation with the PBS and PBS composites, Φ6 particles were kept in contact (incubated) with the films (each PBS or PBS composite film separately) according to the ISO 22196-2011 standard. Then, the P. syringae overnight inoculum/culture was added to 10 mL of LB broth and cultivated at 28° until OD = 0.2 (optical density, in the BioSan bioreactors, BS-010160-A04, BioSan, Riga, Latvia). Finally, 10 µL of each phage lysate was poured into the 10 mL of the host culture (when OD was 0.2). Five Φ6 lysates were amplified in the bacterial cultures