Natural product is still a key player in drug discovery and development programs as a source for novel structures or lead compound. Jeonnam has the largest number of natural resources in Korea with medicinal plants and special biological resources. We conducted bioactivity-guided fractionation methodology and LC/MS based targeted isolation of phytochemicals that discovers therapeutic candidates from natural products by dereplication utilizing in vitro bioassay and active constituents structure prediction. To search the functional natural products, we screened the inhibitory activity of a variety of plant sources on inflammation, oxidant stress using mouse macrophage, and melanoma cells, respectively. Among them, we founded that diterpenoids, flavonoids from Vicia species, triterpenoids, lignan from Osmanthus fragrans var. aurantiacus, and phenolic acid, iridoid from Vitex rotundifolia show significant bioactivities through further investigation to elucidate mechanism using. In silico approach revealed substantial binding energies of docked compounds into established complexes to verify their anti-inflammatory properties. In addition, the content of active components present in the plant was validated by an established method using ultra-performance liquid chromatography method with diode array detection (UPLC-DAD). Pharmacological phytochemicals from domestic plants through bioactivity-guided fractionation and LC-MS based dereplication were discovered as useful functional materials against inflammation and oxidative damage.