Jibril Umar, Ajibola Monisola Umarudeen, Chinonye A. Maduagwuna
Acute toxicity and median lethal dose (LD₅₀) data for Mangifera indica leaf extracts in Drosophila melanogaster remain limited, constraining evaluation of their biological safety. This study investigated the acute toxicity of crude hydro-alcoholic Mangifera indica leaf extract (CHAMILE) in the Harwich strain of D. melanogaster. Qualitative phytochemical screening was conducted using standard phytochemical analytical protocols. Acute toxicity was evaluated in 1–3-day-old flies of mixed sexes (n = 225), distributed across nine replicate treatment vials containing 25 flies each and orally exposed for four days to CHAMILE at 0.00, 0.16, 62.50, 125.00, 250.00, 500.00, or 1000.00 mg/10 g corn meal. Daily and cumulative mortality were recorded, while behavioral toxicity was assessed through negative geotaxis deficits and light–dark preference using the Rapid Iterative Negative Geotaxis (RING) and Two-Choice Tube Light–Dark (TTLD) assays. Lethality percentages and corresponding probit values were plotted against log-transformed extract doses using regression analysis based on Finner’s table and method, while behavioral data were analyzed using one-way ANOVA at P < 0.05. Phytochemical screening detected 12 secondary metabolites, including alkaloids, flavonoids, saponins, and phenolic compounds. All flies exposed to the highest extract concentration died within 72 hours, and the estimated LD₅₀ was 524 mg/10 g corn meal. Significant wall-climbing deficits were also observed in the behavioral assessments. These findings indicate dose-related acute toxicity and behavioral impairment associated with high-dose CHAMILE exposure in D. melanogaster. The detected bioactive compounds may contribute to the observed toxic and physiological effects. This study may represent an initial LD₅₀ assessment of M. indica leaf extract in D. melanogaster and provides preliminary toxicological evidence supporting further safety profiling of different M. indica plant parts across D. melanogaster strains before broader toxicological implications are considered.