Antioxidant, Anti‐Skin Aging, Anti‐inflammatory, and Anti‐acetylcholinesterase Activities of Rourea oligophlebia Extracts

AbstractThe objective of this study was to evaluate the antioxidant, anti‐skin‐aging, anti‐inflammatory, and anti‐acetylcholinesterase activities of the hexane (n‐hex), AcOEt, 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 μg/mL for ABTS⋅+ and from 5.69 to 7.65 μg/mL for DPPH⋅+ except the n‐hex extract. The 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 direct scavenging activity against reactive oxygen species and upregulate cellular antioxidant machinery. 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, AcOEt, and BuOH extracts with IC50 values from 23.21 to 47.1 μg/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 responses.