J Nutr Health.  2013 Oct;46(5):401-409.

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

• Kang YH
• Lee YS
• Kim KK
• Kim DJ
• Kim TW
• Choe M

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.

Keyword

Smilax china L; anti-diabetic activity; anti-obesity activity; antioxidant; organic solvent fraction

MeSH Terms

1-Butanol
alpha-Glucosidases
Asian Continental Ancestry Group
Biphenyl Compounds
China*
Herbal Medicine
Humans
Inhibitory Concentration 50
Korea
Picrates
Plants
Smilax*
Solvents
Water
1-Butanol
Biphenyl Compounds
Picrates
Solvents
Water
alpha-Glucosidases

Figure

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  Fig. 1 Extraction and fractionation of Smilax china L. leaf extracts(SCLE) by using various solvents

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  Fig. 2 Total polyphenol content (A) and total flavonoid content (B) of SCLE fractions. Garlic acid and quercetin were used as standard compounds for the measurement of polyphenol and flavonoid contents respectively. Results are presented as Mean ± SD of three independent experiments. **: p < 0.001 as compared to the SCLE.

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  Fig. 3 SOD-like activity of SCLE fractions. SOD-like activity assay was performed by using a range of SCLE concentrations. Ascorbic acid was used as positive control. Results are presented as Mean ± SD of three independent experiments. *: p < 0.05 as compared to the SCLE.

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  Fig. 4 Anti-diabetic activity of SCLE fractions. α-Glucosidase inhibitory activity assay was performed using a range of concentrations (incubation time, 30 min)(A) and time-points (concentration, 0.25 mg/mL)(B). Acarbose was used as positive control. Results are presented as Mean ± SD of three independent experiments. *: p < 0.05, **: p < 0.001 as compared to the SCLE. #p < 0.001 as compared to the acarbose.

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  Fig. 5 Effects of SCLE fractions on lipid accumulation. 3T3-L1 adipocytes were stained with Oil-Red O for 1 hr. Stained oil droplets were dissolved in isopropanol and quantified by spectrophotometric analysis at 500 nm. Results are expressed as Mean ± SD of three independent experiments and each sample was measured in triplicate. **: p < 0.001 as compared to the control.

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