Study on antioxidative, antidiabetic and antiobesity activity of solvent fractions of smilax china L. leaf extract / 한국영양학회지

ABSTRACT

Smilax china L., a native plant found in Asian countries, has several medicinal properties including antioxidant, anti-inflammatory, and anti-cancer effects. Although the root of the plant is commonly used as traditional herbal medicine in Korea and China, the medicinal properties of the leaves have not gained the same attention. In this study, we analyzed the antioxidant activity, alpha-glucosidase inhibitory effect and lipid accumulation inhibition effect of Smilax china L. leaf water extract (SCLE) and its solvent fractions. SCLE was fractionated by using a series of organic solvents, including ethylacetate (EA) and n-butanol (BuOH). The EA fraction had the highest total polyphenol content (440.20 +/- 12.67 mg GAE/g) and total flavonoid content (215.14 +/- 24.83 mg QE/g). The radical scavenging activity IC50 values of the EA fraction for 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azino-bis-(3-ethylbenzthiazoline)-6-sulfonic acid (ABTS) were 0.022 mg/mL and 0.13 mg/mL, respectively. Further, SOD-like activity and reducing power values of the EA fraction were higher than those of the other fractions. However, both the alpha-glucosidase and lipid accumulation inhibition assays showed that the BuOH fraction (83.35 +/- 4.18% at 1 mg/mL) and water extract (11.27 +/- 2.67%) were more effective than the EA fraction (64.13 +/- 6.35%, and 45.66 +/- 7.20%). These results provide new insights into the potential anti-diabetic and anti-obesity effects of Smilax china L. leaf.