## 3 Results
### Effect of Herbal Extracts on LPS-Induced NO Production in RAW 264.7 Cells
In the group stimulated with 100 ng/mL LPS, the NO levels were 21.52 \(\pm\) 0.42 \(\upmu\)g/mL, while in the experimental group treated with 12.5 \(\upmu\)M of ginseng Rg1, there was no significant change, with the NO levels at 20.81 \(\pm\) 0.33 \(\upmu\)g/mL. In the group treated with 25 \(\upmu\)M ginseng Rg1, the NO levels decreased to 20.00 \(\pm\) 0.22 \(\upmu\)g/mL (\(p\) < 0.05). TheNO levels decreased (\(p\) < 0.001) (Figure 3) in the groups treated with 50 \(\upmu\)M and 100 \(\upmu\)M ginseng Rg1 to 16.76 \(\pm\) 0.17 \(\upmu\)g/mL and 8.10 \(\pm\) 0.29 \(\upmu\)g/mL, respectively. No cytotoxicity was observed at all concentrations (12.5, 25, 50, and 100 \(\upmu\)M) of glycyrrhizin, similar to that seen in the untreated group. In the group stimulated with 100 ng/mL LPS, the NO levels were 21.52 \(\pm\) 0.42 \(\upmu\)g/mL, while in the experimental group treated with 12.5 \(\upmu\)M glycyrrhizin, there was no significant change in the NO levels at 21.29 \(\pm\) 0.22 \(\upmu\)g/mL. In the group treated with 25 \(\upmu\)M glycyrrhizin, the NO levels decreased to 20.33 \(\pm\) 0.17 \(\upmu\)g/mL, but the difference was not statistically significant. NO levels reduced (\(p\) < 0.001) to 17.33 \(\pm\) 0.34 \(\upmu\)g/mL and 11.67 \(\pm\) 0.60 \(\upmu\)g/mL in the groups treated with 50 \(\upmu\)M and 100 \(\upmu\)M glycyrrhizin, respectively (Figure 3). No cytotoxicity was observed at concentrations of 12.5, 25, 50, and 100 \(\upmu\)M 6-gingerol, similar to that seen in the untreated group. In the group stimulated with 100 ng/mL LPS, the NO levels were 20.67 \(\pm\) 0.27 \(\upmu\)g/mL, while in the groups treated with 12.5 \(\upmu\)M, 25 \(\upmu\)M, 50 \(\upmu\)M, and 100 \(\upmu\)M 6-gingerol, there was a decrease (\(p\) < 0.001) in the NO levels to 13.62 \(\pm\) 0.17 \(\upmu\)g/mL, 11.14 \(\pm\) 0.80 \(\upmu\)g/mL, 8.57 \(\pm\) 0.43 \(\upmu\)g/mL, and 4.76 \(\pm\) 0.48 \(\upmu\)g/mL, respectively (Figure 3). Figure 2: _Cont._  
Figure 2: Effects of the 10 extracts on inhibition of nitric oxide (NO) production. RAW 264.7 cells were pre-treated with various concentrations of the 10 extracts. (**A**): Cytotoxic effects of the 10 extracts. (**B**): NO production upon treatment with the 10 extracts. Results have been expressed as mean \(\pm\) SEM (\(n=3\)). Statistical analysis was carried out by means of ANOVA with [PERSON]’s post-hoc test, using software R version 3.3.3. # \(p<0.05\), ## \(p<0.01\), ### \(p<0.001\), compared to the non-treated group; * \(p<0.05\), *** \(p<0.001\), compared to the LPS-treated group. Figure 3: Inhibitory effects of liquiritin, ginseng Rb1, ginseng Rg1, glycyrrhizin, and 6-gingerol in RAW 264.7 cells. The cells were pre-treated with various concentrations of active compounds from Lizhong-tang (liquidiritin, ginseng Rb1, ginseng Rg1, glycyrrhizin, and 6-gingerol). (**A**): Cytotoxic effects of the active compounds of Lizhong-tang. (**B**): Inhibition of nitric oxide production by the active compounds of Lizhong-tang. RAW 264.7 cells were treated with lipopolysaccharideacharide  
(LPS; 100 ng/mL) and samples. The data have been represented as mean \(\pm\) SEM. Statistical significance was evaluated by means of ANOVA followed by [PERSON]'s post-hoc test, using software R version 3.3.3. **_p_ < 0.001, as compared to the normal group; *_p_ < 0.05, and ***_p_ < 0.001, as compared to the LPS-treated group. Evaluation of Inhibition of LPS-Induced NO Production in RAW 264.7 Cells by a Mixture of Liquiritin and 6-Gingerol  
In RAW 264.7 cells, the inhibition of NO production by five active compounds (liquiritin, ginseng Rb1, ginseng Rg1, glycyrrhizin, and 6-gingerol) was evaluated. Liquiritin and 6-gingerol, which showed the best inhibitory efficacy, were evaluated at the highest concentration of 50 uM. Following that, the effect of a mixture of liquiritin and 6-gingerol mixture on the inhibition of NO production was also evaluated. There was no cytotoxicity upon treatment with any concentration of liquiritin (6.25, 12.5, 25, and 50 uM), similar to that seen in the untreated group.