EFFECTS OF STORAGE CONDITIONS ON POLYPHENOL AND TRITERPENOID SAPONIN CONTENT AND THE ANTIOXIDANT CAPACITY OF ETHANOLIC EXTRACT FROM LEAVES OF Polyscias fruticosa (L.) Harms

Tóm tắt

The objective of this study was to evaluate effects of temperatures (5 °C, 30 °C, and 60 °C) on the concentration of polyphenol and triterpenoid saponin and the antioxidant capacity of the ethanolic extract from the leaves of Polyscias fruticosa (L.) Harms during storage. Regression analysis revealed that the antioxidant capacity highly correlated with the content of polyphenol and triterpenoid saponin. After 30 days, the extract stored at 5 °C showed the decreases of total triterpenoid saponin, total polyphenol, DPPH free radical scavenging, and ferric reducing power were 9.55%, 19.81%, 4.18%, and 34.6%, respectively. These values were lower than those after storage at 30 °C and 60 °C. Thus, storage of the extract at low temperature (5 oC) will restrict losses of the extract’s bioactivity and improve the quality of final products.
Keywords: Polyscias fruticosa (L.) Harms, total triterpenoid saponin content, total polyphenol content, antioxidant capacity, storage temperature.