Some Malaysian plants were extracted using 80% methanol and screened for antioxidant and toxicity effects on human neuroblastomacells line (SH-SY5Y cells) and zebrafish(Daniorerio) embryos. Antioxidant assay shows high activities with of IC50 1–100 µg/mL with Melastoma malabathricum (leaf and stem), Murraya koenigii (leaf), Curcuma longa (leaf and rhizome), Ficus deltoidea (leaf), Phaleria macrocarpa (leaf) and Ginkgo biloba (seed). IC50 of 100-200 µg/mL with Polygonum minus (leaf and stem) with DPPH and FRAP assay while IC501-100 µg/mL was observed in Polygonum minus (leaf and stem) and Paederia foetida (leaf) using FRAP assay. Result of toxicity study discloses LC50 >1000 µg/mL with Curcuma longa (leaf) and Ginkgo biloba (seed), LC50 of 500-1000 µg/mL with Melastoma malabathricum (leaf and stem), Polygonum minus (stem), and Ficus deltoidea (leaf) in SH-SY5Y cells. In Zebrafish embryos (0-7 days post fertilization), Paederiafoetida (leaf), Ginkgo biloba (seed) and Curcuma longa (leaf) shows no effect. LC50of 200-500 µg/mL was observed in Murraya koenigii (leaf) and Phaleria macrocarpa (leaf) in SH-SY5Y cells and Zebrafish embryos. LC50 of 250.3±0.79 and 279.4±0.22 was recorded in Clinacanthus nutans (leaf) and Paederia foetida (leaf) in SH-SY5Y cells only. High antioxidant activities and low toxicity effect of these plants revealed their benefit to be used as medicinal supplement to prevent diseases caused by radicals.

Keywords: Antioxidants; DPPH; FRAP; Malaysian Medicinal Plant; SH-SY5Y cells and Zebrafish (Daniorerio).