title: Comparative evaluation of rosmarinic acid, methyl rosmarinate and pedalitin isolated from Rabdosia serra (MAXIM.) HARA as inhibitors of tyrosinase and α-glucosidase.
abstract: Rabdosia serra has been used in traditional Chinese medicine for centuries. In order to illustrate the pharmaceutical activity of R. serra as hypoglycaemic and skin-whitening agents, rosmarinic acid (confirmed as the major compound in R. serra), methyl rosmarinate and pedalitin isolated from R. serra were evaluated for their inhibitory effects and mechanisms on tyrosinase and α-glucosidase. The inhibitory effects on both tyrosinase and α-glucosidase were in decreasing order, pedalitin>methyl rosmarinate>rosmarinic acid. The IC50 values for the tyrosinase and α-glucosidase activity inhibited by pedalitin were 0.28 and 0.29mM, respectively. Both rosmarinic acid and methyl rosmarinate were considered as noncompetitive inhibitors of tyrosinase, while pedalitin was suggested to be a mixed-type inhibitor of tyrosinase. In the assay of α-glucosidase inhibition, rosmarinic acid was found to be a competitive inhibitor, whereas both methyl rosmarinate and pedalitin were considered as mixed-type inhibitors.
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou 510640, China.
authors.forename: Lianzhu
authors.initials: L
authors.lastname: Lin
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou 510640, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Dong
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou 510640, China.
authors.forename: Haifeng
authors.initials: H
authors.lastname: Zhao
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou 510640, China.
authors.forename: Lingrong
authors.initials: L
authors.lastname: Wen
authors.affiliation: Key Laboratory of Plant Resource Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
authors.forename: Bao
authors.initials: B
authors.lastname: Yang
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou 510640, China; Pulp & Paper Engineering State Key Laboratory, South China University of Technology, Guangzhou 510640, China. Electronic address: femmzhao@scut.edu.cn.
authors.forename: Mouming
authors.initials: M
authors.lastname: Zhao
keywords: Inhibitory effects; Mushroom tyrosinase; Phenolics; Rabdosia serra (MAXIM.) HARA; Yeast α-glucosidase