33F-18 Antioxidative properties and in vitro hepato-protective activity of Bupleurum kaoi leaf infusion

C. -Y. TSENG¹, C. -T. Liu¹, W. L. Chen², and Y. -M. Weng¹. (1) Department of Food Science, National Chiayi University, 300 University Road, Chiayi, 600, Taiwan, (2) Department of Applied Chemistry, National Chiayi University, 300 University Road, Chiayi, 600, Taiwan

Antioxidative properties and in vitro hepato-protective activity of Bupleurum kaoi leaf infusion C.-Y. TSENG, C.-T. Liu, W.L. Chen, and Y.-M. Weng, Department of Food Science, National Chiayi University, 300 University Road, Chiayi (60083), TAIWAN, ROC Bupleurum kaoi has been used in the traditional Chinese herbal medicine as the major component for curing hepatitis. Among many varieties of this species, B. kaoi Liu, Chao et Chuang is the indigenous one in Taiwan. In the Chinese medicine, the root is the only tissue of this plant used. Since the aerial parts such as stems and leaves also contain bioactive components, it is of practical economical importance to use these tissues in preparation of health promoting products. Leaf infusion is one of the most feasible commercial products of leaves. The objectives of the present study were to manufacture the herbal infusion from the leaves of B. kaoi and to investigate the beneficial properties of the infusion. The harvested leaves of B. kaoi Liu, Chao et Chuang were withered and dried with hot air. The leaf infusion was made by soaking in water and then boiled. The leaf infusion was preconcentrated and freeze-dried into powder form which was used in the tests. The antioxidant properties (DPPH free radical scavenging, inhibition of the superoxide anion formation, and superoxide anion scavenging) as well as hepatoprotective activity (against acetaminophen or carbon tetrachloride-induced toxicity on rat hepatic cells) were demonstrated. The calculated IC50 of DPPH free radical scavenging activities of leaf infusion was 0.46 mg/ml. The leaf infusion at the level of 5 mg/ml inhibited the superoxide anion formation by 63.6%. As for the peroxide scavenging activity, leaf infusion at the level of 30 mg/ml could reach a 90% removal rate. Leaf infusion also showed remarkable hepato-protective capability against the action of acetaminophen and carbon tetrachloride.

In conclusions, the leaf infusion made from B. kaoi leaves possessed antioxidant activities and hepatoprotective capacity. The leaf infusion is a feasible way to utilize the aerial parts of this plant.