This project tested a novel, quantitative screening framework to determine whether social isolation increases lipid peroxidation-associated oxidative stress and whether ginger essential oil (GEO) from Zingiber officinale reduces that damage in vivo. Oxidative damage was measured as malondialdehyde (MDA) concentration.
Oxidative stress contributes to 85% of human diseases and occurs when reactive oxygen species overwhelm antioxidant defenses, driving lipid peroxidation and MDA formation. Many pharmacologic options have safety and monitoring burdens, so safer, low-cost interventions are needed. GEO contains antioxidant and anti-inflammatory phytochemicals, but its in vivo dose response under social stress remains poorly defined.
Male Canton-S Drosophila melanogaster were assigned to a 2 × 4 factorial design with two housing conditions (group-housed or socially isolated) and four diets (vehicle, low GEO, medium GEO, high GEO). Homogenates were analyzed with a TBARS assay. Samples were homogenized, protein was precipitated with TCA, supernatants were reacted with TBA under heat, and absorbance was read at OD535. Using Beer-Lambert theory, blank-corrected absorbance was converted to MDA (µM) with an MDA standard curve (0, 9, 18, 30 µM; R² = 0.992). Ten biological replicates were analyzed per group.
Isolation increased baseline oxidative stress, with higher mean MDA in isolated controls (27.4 µM) than group-housed controls (17.9 µM) with a 53.1% increase. GEO reduced MDA in both housing conditions. The strongest reduction occurred at the medium dose, decreasing group-housed MDA from 17.9 to 12.2 µM (31.8%) and isolated MDA from 27.4 to 20.0 µM (27.0%). The high dose showed a partial rebound. Statistical separation was strong (ANOVA F(7,72) = 424.8, p = 7.0 × 10^-56, eta² = 0.976).
GEO reduced lipid peroxidation in vivo under both baseline and stress conditions, with a clear optimal mid-dose effect. These findings support Drosophila as a rapid, biomarker-based model for screening plant-derived oxidative stress interventions with strong quantitative resolution.