Identification and Extraction Optimization of Active Constituents in <i>Citrus junos</i> Seib ex TANAKA Peel and Its Biological Evaluation

• Main Authors: Jung-hyun Shim, Jung-il Chae, Seung-sik Cho
• Format: Article
• Language: English
• Published: MDPI AG 2019-02-01
• Series: Molecules
• Subjects: <i>Citrus junos</i> Seib ex TANAKA; antioxidant; xanthine oxidase; elastase
• Online Access: https://www.mdpi.com/1420-3049/24/4/680

<i>Citrus junos</i> Seib ex TANAKA possesses various biological effects. It has been used in oriental remedies for blood circulation and the common cold. Recently, biological effects of <i>C. junos</i> peel have been reported. However, optimization of the biological properties of <i>C. junos</i> peel preparations has yet to be reported on. We developed a high-performance liquid chromatography (HPLC) method for quantification of the active constituents in <i>C. junos</i> peel. Hot water and ethanolic extracts of <i>C. junos</i> peel were prepared and their chemical profiles and biological activities were evaluated. The 80% ethanolic extract demonstrated the greatest antioxidant activity and phenolic content, while the 100% ethanolic extract had the greatest xanthine oxidase inhibitory activity. Elastase inhibition activity was superior in aqueous and 20% ethanolic extracts. The contents of two flavonoids were highest in the 100% ethanolic extract. We postulated that the antioxidant and anti-aging effects of <i>C. junos</i> peel extract could be attributed to phenolics such as flavonoids. Our results suggest that the flavonoid-rich extract of <i>C. junos</i> may be utilized for the treatment and prevention of metabolic disease and hyperuricemia while the water-soluble extract of <i>C. junos</i> could be used as a source for its anti-aging properties.