Two instruments were used to acquire results: Malvern Spraytec (Malvern Panalytical, Malvern, UK) and LAS, as mentioned above. Antimicrobial Activity against Biological AerosolsĪ very important first step of the investigation was focused on characterisation of the particle size of droplets produced by the VaxiPod. Reduction in viability (%) was calculated based on the reduction in colony count on the oil vapour exposed plates with respect to the control plates (Equation (1)). Control plates were stored at room temperature and then collected, incubated and counted in the same way. The plates were incubated at 37 ☌ for 24 h for bacteria and 25 ☌ for 3–7 days for fungi, and CFUs were counted after incubation. To examine the long-term growth inhibitory effect of the oil mixture supplied by the oil atomiser, one set of plates with each type of microorganisms was removed from the enclosure in 0, 15, 24 and 48 h. Inoculated plates were opened inside the enclosures and placed on the bottom part of the enclosures for exposure to the essential oil mixture. Appropriate serial dilution of the bacterial and fungal cultures (to obtain 100–300 CFU) was plated on NA/MEA plates. They were conducted in the enclosure for selected microorganisms, including E.
Several experiments were undertaken to evaluate this scenario. It is also important to assess any potential impact of the presence of nutrients on surfaces that may affect the survival of microorganisms. The results look very promising for further development of bioaerosol inactivating procedures and technologies for air quality control applications. Twenty-four to forty-eight hours were required to achieve inactivation above 90% of most of the tested microbes on solid surfaces (stainless steel discs and agar plates), whilst similar efficiency of inactivation on fibrous filter surface as well as in aerosol form was achieved over 30–60 min of the process run. It was found that the device was capable of operating continuously over 24-h periods, providing sufficient aerosol concentration to efficiently inactivate microorganisms both on the surface and in airborne form. This project reports the results of investigation of the antimicrobial activity of essential oils natural for Australia (tea tree oil, eucalyptus oil and lemon myrtle) distributed by newly developed VaxiPod device for various scenarios, including bacterial, viral and fungal inactivation on various surfaces and in aerosol form. Various studies demonstrated quite broad ranges of the efficiency of essential oils in the control of biological aerosols. Currently, due to the global pandemic caused by severe acute respiratory syndrome coronavirus SARS-CoV-2, new procedures and devices for effective disinfection of indoor air are of obvious interest.
0 kommentar(er)
