Isolation and identification of antioxidant phenylpropanoids from the fruit peel of Akebia trifoliata koidz

• Published in: FOOD SCIENCE AND TECHNOLOGY RESEARCH Vol. 29; no. 1; pp. 27 - 34
• Main Authors: Kadowaki, Wataru, Sugahara, Yuki, Toyoizumi, Tomoyasu, Nakajima, Teruko, Kumazawa, Shigenori
• Format: Journal Article
• Language: English
• Published: Tsukuba Japanese Society for Food Science and Technology 2023; The Japanese Society for Food Science and Technology; Japan Science and Technology Agency
• Subjects: Agricultural products; Akebia trifoliata; antioxidant; Antioxidants; Caffeoylquinic acid; calceolarioside B; Fruits; Functional materials; peel; Phenylpropanoids
• ISSN: 1344-6606; 1881-3984
• DOI: 10.3136/fstr.FSTR-D-22-00127

In the course of screening for antioxidant agricultural products in Shizuoka Prefecture, Japan, we found that Akebia trifoliata Koidz fruit had a high activity. Furthermore, we found that the peel of A. trifoliata showed remarkable antioxidant activity compared to other parts of the fruit. We isolated seven known phenylpropanoids, including caffeoylquinic acids from the peel of A. trifoliata: 5-O-caffeoylquinic acid (1), 4-O-caffeoylquinic acid (2), 3-O-caffeoylquinic acid (3), 4,5-di-O-caffeoylquinic acid (4), 3,5-di-O-caffeoylquinic acid (5), calceolarioside B (6), and (4-hydroxyphenyl)-ethyl-6-O-(E)-caffeoyl-β- d -glucopyranoside (7). These isolated compounds were found to contribute to the antioxidant activity of the peel, with 6 exhibiting the strongest activity amongst them. Quantitative analyses showed that 6 is abundant in the peel of A. trifoliata. Therefore, the peel of A. trifoliata can be effectively used as a functional material with antioxidant activity.