Comparison between the Biological Activities of Leaf and Flower Extracts of Osmanthus fragrans var. aurantiacus and Osmanthus asiaticus Lour. var. fragrans

Abstract

Purpose: This study aims to verify the biological activities of leaf and flower extracts of <i>Osmanthus fragrans</i> var. aurantiacus (OF) and <i>Osmanthus asiaticus</i> Lour. var. fragrans (OA), which can be used in the cosmetics industry.Methods: Ethanol extraction of the flowers and leaves of OF and OA was performed to determine the total polyphenol and flavonoid content, the scavenging activities of DPPH and ABTS radicals, the inhibitory effects on elastase and tyrosinase, and antibacterial effects.Results: The total polyphenol content of leaf and flower extracts was determined to be 135.64 μg/mL and 80.06 μg/mL, respectively, for OF and 104.11 μg/mL and 71.64 μg/mL, respectively, for OA. The total flavonoid content of leaf and flower extracts was found to be 123.48 μg/mL and 86.20 μg/mL, respectively, for OF and 104.07 μg/mL and 78.13 μg/mL, respectively, for OA. At a concentration of 500 μg/mL, the DPPH scavenging activity of leaf and flower extracts was found to be 84.49% and 72.08%, respectively, for OF and 77.12% and 68.75%, respectively, for OA. The ABTS radical scavenging activity of leaf and flower extracts was determined to be 90.36% and 83.15%, respectively, for OF and 88.14% and 80.90%, respectively, for OA. The inhibitory effect of leaf and flower extracts on elastase was confirmed to be 58.31% and 46.14%, respectively, for OF and 51.22% and 39.26%, respectively, for OA. The inhibitory effects of leaf and flower extracts on tyrosinase were found to be 57.24% and 48.12%, respectively, for OF and 52.15% and 41.12%, respectively, for OA. Upon evaluation, the leaf and flower extracts of OF and OA exhibited antibacterial effects on <i>Propionibacterium acnes</i> (<i>P. acnes</i>) and <i>Malassezia furfur</i> (<i>M. furfur</i>).Conclusion: Among the ethanol extracts of the leaves and flowers of both species, the leaf extract of OF was confirmed to have not only an antioxidant effect but also a high inhibitory effect on elastase and tyrosinase, along with antibacterial effects. Therefore, it is expected to have high potential as a cosmetic material.