Pharmacological activities of Nepenthes miranda extracts

Carnivorous Nepenthes plants exhibit many ethnobotanical uses and their extracts possess many pharmacological activities. In this study, we prepared different extracts from leaves, stems, pitchers, and flowers of N . miranda (Nm) and investigated the antioxidant, antibacterial, anticancer, and anti‐inflammatory properties. To evaluate extraction efficiency, different solvents such as methanol, ethanol, acetone, and distilled water were used individually for Nm extract preparations. Through DPPH radical scavenging assay, Folin‐Ciocalteu method, and aluminium chloride calorimetric analysis, the stems extract obtained by 100% acetone (Nm‐s‐a) showed the highest total antioxidant activity, total phenolic content, and total flavonoid content, respectively. In addition, we found that the same extract also exhibited the highest antibacterial activity against three pathogens, namely, Staphylococcus aureus , Pseudomonas aeruginosa , and Escherichia coli . The inhibition zones of Nm‐s‐a determined by agar‐well diffusion assay ranged from 9–29 mm and were in the following order: E. coli > S. aureus > P. aeruginosa . To demonstrate the cytotoxicity effect of Nm‐s‐a, human embryonic kidney 293 cells (HEK 293) and melanoma cells were cultured with various concentrations of Nm‐s‐a. Furthermore, inhibition of human neutrophil elastase by Nm‐s‐a was also found, suggesting the anti‐inflammatory activity. These results indicated that N . miranda may have some medicinal potentials. To further elucidate the structure‐activity relationship, our laboratory is currently using LC‐MS to isolate and identify the active compounds from Nm‐s‐a. This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .