Water-dispersible MgO nanoparticles were tested to investigate their cytotoxic effects on oxidative stress gene expression. In this in vitro study, genes related to reactive oxygen species (ROS), glutathione S-transferase (GST) and catalase, were quantified using real-time polymerase chain reactions (molecular level) and molecular beacon technologies (cellular level). The monodispersed MgO nanoparticles, 20 nm in size, were used to treat human cancer cell lines (liver cancer epithelial cells) at different concentrations (25, 75 and 150 µg/mL) and incubation times (24, 48 and 72 h). Both the genetic and cellular cytotoxic screening methods produced consistent results, showing that GST and catalase ROS gene expression was maximized at 150 µg/mL nanoparticle treatment with 48 h incubation. However, the genotoxic effect of MgO nanoparticles was not significant compared with control experiments, which indicates its significant potential applications in nanomedicine as a diagnostic and therapeutic tool.

Particulate matter has been increasing worldwide causing air pollution and serious health hazards. Owing to increased time spent indoors and lifestyle changes, assessing indoor air quality has become crucial. This study investigated the effect of watering and drought and illumination conditions (constant light, light/dark cycle, and constant dark) on particulate matter2.5 (PM2.5) removal and surface characterization of leaf in a botanical plant-based biofilter system. Using Ardisia japonica and Hedera helix as experimental plants in the plant-based biofilter system, PM2.5, volatile organic carbon, and CO₂, as the evaluators of indoor air quality, were estimated using a sensor. Morphological and chemical changes of the leaf surface (i.e., roughness and wax) associated with PM2.5 removal were characterized via scanning electron microscopy, Fourier transform infrared spectroscopy, and atomic force microscopy. The highest PM2.5 removal efficiency, stomata closure, high leaf roughness, and wax layer were observed under drought with constant light condition. Consequently, PM2.5 removal was attributed to the combined effect of leaf roughness and wax by adsorption rather than stomatal uptake. These results suggest that operating conditions of indoor plant-based biofilter system such as watering (or drought) and illumination may be applied as a potential strategy for enhancing PM2.5 removal.

Commiphora myrrha (T.Nees) Engl. resin extracts were prepared via immersion in extraction solvents (hot water, DMSO, hexane, ethanol, and methanol) which have various physical properties, such as different polarity and dielectric constant values. Methanolic C. myrrha (T.Nees) Engl. resin extracts showed broad antibacterial activity against isolated airborne bacteria. All methanolic C. myrrha (T.Nees) Engl. resin extracts were analyzed using GC-MS and Furanoeudesma-1,3-diene and curzerene were found as the main terpenoids. In addition, the methanolic C. myrrha (T.Nees) Engl. resin extracts were found to have antiviral activity (81.2% viral RNA inhibition) against the H1N1 influenza virus. Biochars (wood powder- and rice husk-derived) coated with C. myrrha (T.Nees) Engl. resin extracts also showed antiviral activity (22.6% and 24.3% viral RNA inhibition) due to the adsorption of terpenoids onto biochar. C. myrrha (T.Nees) Engl. resin extract using methanol as the extraction solvent is a promising agent with antibacterial and antiviral efficacy that can be utilized as a novel material via adsorption onto biochar for air filtration processes, cosmetics, fertilizers, drug delivery, and corrosion inhibition.

Commiphora molmol myrrh resin extracts, which have different physical properties such as polarity and dielectric constant, were prepared by immersion in extraction solvents (hot water, DMSO, hexane, ethanol, and methanol). Methanolic myrrh resin extracts showed broad antibacterial activity against isolated airborne bacteria. Furanoeudesma-1,3-diene and curzerene, as the main terpenoids in the methanolic myrrh resin extract, were analyzed using GC-MS, and the methanolic myrrh resin extracts were found to have antiviral activity (81.2% viral RNA inhibition) against H1N1 influenza virus. Biochars (wood powder-and rice husk-derived) coated with myrrh resin extracts also showed antiviral activity (22.6% and 24.3% viral RNA inhibition), due to the adsorption of terpenoids onto biochar. Myrrh resin extract using methanol as the extraction solvent is a promising agent with antibacterial and antiviral efficacy, and it can be utilized as a novel material via adsorption onto biochar for air filtration processes, cosmetics, fertilizers, drug delivery, and corrosion inhibition.

Objectives : The purpose of this study was to investigate the effect of spitting behavior on microbial public health in smoking areas. Through this investigation, bacterial concentration and spread of bacteria from the smoking areas were evaluated for the prospective public health and environment.Methods : The number of spitting and the spitting location in the smoking areas were measured visually by observers. For the microbial analysis, filter papers (5 × 5 cm) as sample collectors had been attached to the surface of the smoking areas for a given time. Using the collected filter paper, ATP bioluminescence measurement (RLU), colony forming unit (CFU) were measured. For the estimation of spitting behaviors in the smoking area on the spread microorganisms, saliva containing filters were selected from the areas, and fluorescent powder (0.01 g/cm2) was added to the papers. After 4 hours, the papers around the smoking areas were collected and the fluorescence activity was measured.Results and Discussion : The results showed that there was a clear relationship between the spitting behavior and the microbial activity in the smoking areas. In the case of sampling area A, the highest number of spitting was observed at the lunch hour (102 ± 16 times), and the RLU from the sample collected near the smoking area showed about 5,139 ± 1,267 RLU. When the RLU around the smoking area was measured, the lowest values were found at distance of 11 and 17 m from the cigarette bin (1,329 ± 148 and 1,204 ± 203 RLU), and it was confirmed that smoking and spitting did not occur at this sampling points. In the case of sampling area B, the highest number of spitting (45 ± 6 times) was observed at evening hour, and the RLU from the sample collected near the smoking area showed about 5,274 ± 1,297 RLU. The lowest value was in the sampling area B shown at 11 and 18 m (1,181 ± 243 RLU and 1,148 ± 168 RLU) from the cigarette bin, and it was also confirmed that smoking and spitting did not occur at this sampling points. The results indicate that the spitting during the smoking induced the increases of the microbial contamination of the public environment. The fluorescence powder diffusion analysis indicated that the saliva on the ground surface would enhance the spread of the microorganisms from the smoking area.Conclusions : Spitting in smoking areas can pose a high risk of microbial infection for smokers and non-smokers in smoking areas. Thus extensive and systematic attention related to the smoking manner must be paid to protect our public health.