Antioxidant activity and anti-adipogenic effects of wild herbs mainly cultivated in Korea

Abstract

Wild herbs, which are edible plants that grow in mountainous areas, have diverse biological effects such as anti-obesity and anti-cancer activities. The aim of this study was to evaluate the total phenolic and flavonoid contents as well as the antioxidant activity of methanol extracts of Aster scaber, Ligularia fischeri, Kalopanax pictus, Codonopsis lanceolata, and Cirsium setidens and to assess their effects on lipid accumulation and reactive oxygen species (ROS) production during adipogenesis of 3T3-L1 cells. The results revealed that among the five studied wild herb extracts, Ligularia fischeri showed the highest total phenolic contents (215.8 ± 14.2 mg GAE/g) and Aster scaber showed the highest total flavonoid content (103.9 ± 3.4 mg RE/g). Furthermore, Aster scaber and Ligularia fischeri extracts showed higher antioxidant activity than the other wild herbs. Regarding anti-adipogenic activity, the Cirsium setidens extract significantly inhibited lipid accumulation (~80%) and ROS production (~50%) during adipogenesis of 3T3-L1 cells compared with control cells. These results suggest that wild herbs could be used for the development of functional foods as well as health promoting and pharmaceutical agents.

Figure 1

DPPH radical scavenging activity (a), FRAP activity (b), reducing power (c) and ABTS radical scavenging activity (d) of five wild herb extracts at various concentrations. A, Aster scaber; B, Ligularia fischeri; C, Kalopanax pictus; D, Codonopsis lanceolata; E, Cirsium setidens. All values are presented as the means ± SD. Bars with different letters indicate statistically significant differences among groups at p < 0.05 by one-way ANOVA.

Figure 2

Radical scavenging activity of wild herb extracts as measured by ORAC. (a) Decay curve of fluorescence in the presence or absence of samples. (b) Radical scavenging activity of wild herb extracts expressed as Trolox equivalents. A, Aster scaber; B, Ligularia fischeri; C, Kalopanax pictus; D, Codonopsis lanceolata; E, Cirsium setidens. All values are presented as the means ± SD. Bars with different letters indicate statistically significant differences among groups at p < 0.05 by one-way ANOVA.

Figure 3

Effect of wild herb extracts on the cell viability of 3T3-L1 preadipocytes. Cell viability was determined using the XTT assay. Con, control cells; A, Aster scaber; B, Ligularia fischeri; C, Kalopanax pictus; D, Codonopsis lanceolata; E, Cirsium setidens. All values are presented as the means ± SD. Bars with different letters indicate statistically significant differences among groups at p < 0.05 by one-way ANOVA.

Figure 4

Effect of the five wild herb extracts on lipid accumulation (a) and reactive oxygen species (ROS) production (b) in 3T3-L1 cells during the adipogenesis. Accumulated lipids were stained with Oil Red O reagent and measured based on the absorbance at 490 nm. ROS production was assessed based on the formation of dark-blue formazan and determined by the NBT assay at a wavelength of 570 nm. CON, control cells which were differentiated with MDI; NAC, positive control cells which were differentiated with MDI in the presence of NAC; A–E, cells which were differentiated with MDI in the presence of each sample; A, Aster scaber; B, Ligularia fischeri; C, Kalopanax pictus; D, Codonopsis lanceolata; E, Cirsium setidens. All values are presented as the means ± SD. Bars with different letters indicate statistically significant differences among groups at p < 0.05 by one-way ANOVA.