## 4 Discussion  
This study conducted a comparative analysis of the metabolic profiles of different _Raphanus sativus_ cultivars of RL1, 2, and 3. The RL1 cultivar is a more conventional radial that is often seen commercially; the RL2 cultivar has a unique root skin that is purple and green, and the flesh color is red; and the RL3 cultivar is also known for its purple flesh inside the road [1]. All of the cultivars exhibited different phenotypical characteristics in the roots, but, to go further, the phytochemical analysis of the aerial parts was examined to confirm its metabolite composition. After the extraction of the aerial parts of the _R. sativus_ cultivars, UPLC-Orbitrap-MS analysis was performed. After normalization by the sum of the peak intensities through UPLC-Orbitrap-MS, each extract revealed differences in their metabolite composition. Furthermore, extracts of each cultivars RL1-3 were tested for their anti-inflammatory and antioxidant activities to confirm their differences in medicinal aspects. To go in depth, the comparative analysis between the identified metabolites between the RL1-3 extracts and their influence in their bioactivity was examined.  
The results of the DPPH assay revealed that there was no significant difference in antioxidant properties between the RL1-3 extracts. Thus, the overall difference between the metabolites may not influence its antioxidant effect. In contrast to that, a difference in anti-inflammatory properties is shown from the RL1-3 extracts by measuring the NO production in LPS-stimulated RAW 264.7 cells. In a dose-dependent manner, the RL2 and RL3 extracts both show significant anti-inflammatory effects, but the RL3 extract showed potent activity. Thus, the metabolic change of the identified metabolites can possibly influence the anti-inflammatory property of the cultivar.  
Since flavonoids are well known for their potential health benefits, the composition of identified flavonoid derivatives was suggested to influence the difference in anti-inflammatory properties [46]. Major flavonoid components between the RL1-3 extract were quercetin and kaempfer derivatives, and their antioxidant and anti-inflammatory effect may be attributed primarily to the abundancy of quercetin and kaempfer derivatives [47]. The RL3 extract seemed to have more relative content of quercetin and kaempfer derivatives (**14-16**), which may influence the anti-inflammatory effect. The previous literature has studied that the quercetin glycosylation of three sugar moieties possess potential anti-inflammatory and antioxidant activities [48]. Also, kaempfer glycosides with three or more sugar moieties that were identified from other plant sources have shown significant anti-inflammatory activities as well [49,50].  
On the contrary, previous studies have shown that the \(O\)-glycosylation of flavonoids with a single sugar moiety has suppressed the LPS-induced NO production in BV2 microglial cells and RAW264.7 macrophages [51, 52, 53]. This suggests that the glycosylation of flavonoid aglycone may weaken the anti-inflammatory activity more than its flavonoid aglycone itself [54]. The comparative metabolic change shows that the RL1 extract consists of more quercetin and kaempfer derivatives with a single sugar moiety glycosylated with it. Thus, this suggests that the glycosylation may have weakened the anti-inflammatory property of RL1 cultivar.  
Overall, it is difficult to draw general comments regarding the impact of glycosylation on flavonoids' bioactivity and its influence on human health. It is possible that the effects of the glycosylation of flavonoid may _differ_ in vivo and in human consumption; here, more information needs to be followed up by the correlation of flavonoid glycosylation and its bioactivity. These findings provide empirical evidence that different _R. sativus_ cultivars can be a valuable source for flavonoid derivatives and that other cultivars or radiish can be used as a functional food ingredient.