2019 Volume 25 Issue 5 Pages 695-703
Japanese mint (Mentha arvensis) is a widely used herb for culinary, fragrant, and medicinal applications. In this study, useful substances were obtained from Japanese mint leaves by extraction using subcritical water (180 to 260 °C). The characteristics of the mint extracts, including carbohydrates, proteins, and phenolic content, as well as 2′,2′-diphenyl-1-picryhydrazyl (DPPH) radical scavenging activity were investigated. The highest carbohydrate content was obtained at 180 °C, while the highest amount of protein was obtained at 200 °C. A linear relationship was observed between the phenolic content and DPPH radical scavenging activity. Oligosaccharide was the most abundant sugar in the extracts, as determined by high performance liquid chromatography analysis. The presence of apocynin, a potent non-steroidal anti-inflammatory drug, was identified by gas chromatography-mass spectrometry and its content showed an exponential increase as the temperature was increased from 180 to 260 °C. This study provides practical information for applications of Japanese mint.