Purpose: This study aimed to investigate the optimal collection time of Acer palmatum extract (APE) through anti-oxidant and anti-bacterial activities. Methods: We confirmed the anti-oxidant activity of APE by estimating the total polyphenol content, total flavonoid content, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging effect, and cell viability. In addition, we determined anti-bacterial activities against Staphylococcus aureus, Bacillus subtilis, and Pseudomonas aeruginosa during growth. Results: Anti-oxidant activities of APE peaked in July and November. RAW 264.7 displayed high cell viability in APE concentrations of 5-100 µg/mL in July and November. As a result of conducting anti-bacterial activities, seasonal variation of APE against three bacteria was exhibited. Conclusion: The anti-oxidant and anti-bacterial activities of APE showed seasonal variation, and high cell viability in July and November; therefore, consideration of the optimal seasonal collection time for Acer palmatum could be an important factor attributing to its natural antioxidant properties and the optimal collection time was confirmed especially to be in July and November.

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.