Exploring The Therapeutic Potential Of Carissa Carandas: In Vitro Antioxidant And Anti-Parkinson Activity Evaluation

Abstract

Background Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by dopaminergic neuronal loss, oxidative stress, mitochondrial dysfunction, and neuroinflammation. Natural products rich in bioactive phytochemicals have emerged as promising candidates for neuroprotection. Carissa carandas (Karonda) contains flavonoids, phenolics, triterpenoids, and other secondary metabolites with reported antioxidant and anti-inflammatory properties. This study evaluated the antioxidant and anti-Parkinson potential of the n-hexane extract of Carissa carandas fruits through phytochemical characterization and in vitro biological assays.

Methods:

Fruits of Carissa carandas were collected, authenticated, and extracted using n-hexane. The extract was subjected to CHNS elemental analysis, qualitative phytochemical screening, estimation of total phenolic and flavonoid contents, and GC–MS analysis for phytochemical profiling. Antioxidant activity was assessed using the DPPH free radical scavenging assay. Anti-Parkinson potential was evaluated by monoamine oxidase (MAO-A/B) inhibition assay and neuroprotective assessment using the SH-SY5Y human neuroblastoma cell line through the MTT assay.

Results:
The n-hexane extract showed a recovery yield of 3.34%. Total phenolic and flavonoid contents were 5.82 ± 0.38 mg GAE/100 g extract and 0.49 ± 0.02 mg QE/100 g extract, respectively. The DPPH assay demonstrated comparatively weak antioxidant activity with an IC₅₀ of 530.2 ± 0.32 µg/mL compared with ascorbic acid (8.363 ± 0.024 µg/mL). GC–MS analysis identified 52 phytochemical constituents, including phenethyl acetate, palmitic acid, oleic acid, isopropyl myristate, globulol, and long-chain hydrocarbons. The extract exhibited negligible MAO inhibitory activity (IC₅₀ above the maximum tested dose). In the MTT assay, the extract showed moderate cytotoxicity toward SH-SY5Y cells with an IC₅₀ of 68.69 ± 0.05 µg/mL compared with doxorubicin (48.62 ± 0.04 µg/mL).

Conclusion:
Although the n-hexane extract of Carissa carandas fruits demonstrated limited antioxidant and MAO inhibitory activities, GC–MS analysis confirmed the presence of several biologically relevant phytoconstituents with potential neuroprotective significance. Further investigations using polar extracts, mechanistic cellular models, and in vivo Parkinson's disease models are warranted to validate its therapeutic potential and identify the bioactive constituents responsible for neuroprotection.