Evaluation of Antioxidant and Neuroprotective Activity of Moringa Oleifera and Plectranthus Amboinicus Leaves Against Oxidative Stress- Induced Neurodegeneration

Abstract

Neurodegenerative disorders are closely linked to oxidative stress, which causes damage to nerve cells and leads to memory and cognitive problems. The aim of this study was to evaluate the antioxidant and neuroprotective effects of Moringa oleifera and Plectranthus amboinicus leaf extract using in-vitro cell models. Fresh Moringa oleifera and Plectranthus amboinicus leaves were collected, authenticated, and extracted using the Soxhlet method, which produced a yield of 25.3%. The antioxidant activity of the extract was tested using DPPH and hydrogen peroxide scavenging assays. The results showed that the extract scavenged free radicals in a concentration-dependent manner. The IC₅₀ values were found to be 87.31 µg/ml for the DPPH assay and 49.78 µg/ml for the hydrogen peroxide assay, indicating good antioxidant potential. Cell viability was studied using the MTT assay on Neuro-2A cells. The results confirmed that the extract was non-toxic at lower concentrations, demonstrating good cytocompatibility with neuronal cells. The neuroprotective effect of the extract was further supported by significant inhibition of acetylcholinesterase activity, suggesting a role in improving neurotransmitter function. In addition, the reactive oxygen species (ROS) assay showed that treatment with the extract significantly reduced intracellular ROS levels in hydrogen peroxide-treated cells, confirming its protective effect against oxidative stress. Overall, the study indicates that Moringa oleifera and Plectranthus amboinicus extract are a rich source of natural bioactive compounds with strong antioxidant and neuroprotective properties. Future studies should focus on identifying the active phytochemicals, understanding the molecular mechanisms involved, and confirming these effects using in-vivo animal models. This may help in the development of plant-based therapies for neurodegenerative diseases.