Potency of Rhizopora Spp. Extracts as Antioxidant and Inhibitor of Acetylcholinesterase

The potency of mangrove for traditional medicine has been widely investigated. This study was conducted to investigate the potency of Rhizophora spp. extracts as antioxidant and inhibitor of acetylcholinesterase (AChE). Leaves and fruits of Rhizophora spp. were extracted using gradual polarity solvents, namely n-hexane, ethyl acetate, and methanol. AChE inhibition assay was performed based on Ellman method, meanwhile antioxidant was analyzed based on 2,2-diphenyl-pikrylhydrazyl radical scavenging. Methanol extracts of Rhizophora spp. fruit consistently showed inhibitory activity against AChE. Methanol extract of R. mucronata fruit showed highest inhibitory activity with 50% inhibitory concentration (IC50) of 1 μg/mL, when the IC50 of physostigmine was 0.06 μg/mL. Antioxidant assay against 2,2-diphenyl-pikrylhydrazyl showed that the extract was a potential antioxidant with IC50 of 3.74 μg/mL whereas the IC50 of ascorbic acid was 1.31 μg/mL. The qualitative phytochemical investigation showed that the extract contain tannin, saponin, terpenoid, alkaloid, and flavonoid.