Investigating the Effect of Different Antioxidants on the Stability of Phospholipid Membranes in Beetroot Cells under Oxidative Stress

Abstract

The objective of this study is to investigate the efficacy of selected antioxidants  such as vitamin C (water-soluble), vitamin E (lipid-soluble), as compared to green tea hot water extract (polyphenol-rich)  in stabilizing the phospholipid bilayer in the plasma membranes of beetroot (Beta vulgaris) cells under induced oxidative stress using hydrogen peroxide (H₂O₂). Cell membrane integrity was evaluated by measuring betacyanin leakage, and quantified using spectrophotometric absorbance at 540 nm (calibrated against a standard curve to determine pigment concentration). Results showed that vitamin E gave superior protection (48.4% release at 0.5 mM), attributed to its integration into lipid bilayers in neutralizing peroxyl radicals, followed by green tea water extract (59.3% release) through hydrogen bonding and metal chelation. While vitamin C provided limited efficacy (73.6% release), attributed to scavenging aqueous-phase ROS. Statistical analysis (p < 0.05) verified significant differences between lipid-polyphenol-soluble and water-soluble antioxidants. The investigation highlights the crucial role of antioxidant solubility in stabilizing cell membranes, with applications in reducing post-harvest food losses during storage. Concentration measurements enhanced accuracy by standardizing data across beetroot batches, while dual-method validation (absorbance and concentration) strengthened reproducibility. Limitations, such as plant cell walls and solvent effects (ethanol), open opportunities for future research using erythrocytes or multi-ROS systems. Innovations in ROS-responsive packaging and tailored antioxidant blends could be a revolution in food storage, aligning with Sustainable Development Goals. This research bridges biochemistry and sustainable agriculture, offering actionable strategies to enhance food security and mitigate agricultural waste.