Buranasudja_2023_Chem.Biodivers__e202201096

The objective of this study was to evaluate the antioxidant, anti-skin aging, anti-inflammatory, and anti-acetylcholinesterase activities of the n-hexane (n-hex), EtOAc, n-BuOH, MeOH, and aqueous extracts from R. oligophlebia roots. The total phenolic and flavonoid contents (TPC and TFC) were determined using Folin-Ciocalteu and AlCl3 colorimetric assays. The antioxidant capacity was examined by reducing power (RP), ferric reducing antioxidant power (FRAP), ABTS +, and DPPH + radical cation assays. All extracts potentially exhibited antioxidant activity with IC50 values ranging from 2.93 to 5.73 microg/mL for ABTS + and from 5.69 to 7.65 microg/mL for DPPH + except the n-hex extract. The n-BuOH, MeOH, and aqueous extract possess promising anti-skin aging activities, as observed by an attenuation of UV-A toxicity on human keratinocytes. We proposed that these anti-skin aging properties are possibly due to a.) direct scavenging activity against reactive oxygen species; b.) an enhancement in the expression of cellular antioxidant machineries. Moreover, we found that the antioxidant capacity was well correlated with anti-inflammatory capacity against nitric oxide (NO) production in terms of the n-hex, EtOAc, and n-BuOH extracts with IC50 values from 23.21 to 47.1 microg/mL. In contrast, these activities were found to be poorly correlated with AchE activity. To the best of our knowledge, this is the first report of the antioxidant, anti-skin aging, anti-inflammatory, and anti-acetylcholinesterase activities of the extracts of R. oligophlebia roots. These findings indicated that this species could be a potential source of natural antioxidant, anti-aging, and anti-inflammatory agents. Consequently, it may be suggested as a medicinal plant that prevents diseases related to oxidative stress and inflammatory response.