Afr. J. Biomed. Res. Vol. 24 (January, 2021); 99 - 108 Research Article Pineapple Fruit Extract Prolonged Lifespan and Endogenous Antioxidant Response in Drosophila melanogaster Exposed to Stress. Ajagun-Ogunleye O.M. 1, 2 , Adedeji A. A. 2, 3, 4 , *Vicente-Crespo M. 1, 2, 5 1 Department of Biochemistry, School of Biomedical Sciences, Kampala International University-Western Campus, Uganda. 2 Institute of Biomedical Research, Kampala International University-Western Campus, Uganda. 3 Department of Pharmacology, School of Biomedical Sciences, Kampala International University-Western Campus, Uganda. 4 Current Address: Department of Pharmacology, Faculty of Basic Medical Science, Obafemi Awolowo College of Health Sciences, Olabisi Onabanjo University, PMB 2001, Sagamu, Ogun State. 5 Current Address: African Population and Health Research Center, Nairobi, Kenya. ABSTRACT Free radical-induced cellular damage accelerates ageing. The WHO anticipated that 22% of the population will be over 60years by the year 2050 and 80% of those will live in low-and-middle-income countries (LMIC). It is, therefore, paramount to find local and readily available compounds that could reduce age-induced burden in LMIC. The methanol fruit extract of Ananas sativa and its fractions were evaluated for anti-ageing activity in the fruit fly, Drosophila melanogaster w 1118 flies. Experimental flies were fed on food supplemented with 5, 10, and 20mg/ml methanolic fruit pulp-juice extract lifespan, reproduction, learning, memory and stress resistance assays were evaluated. Phytochemical composition and the percentage inhibition of the fruit extract on 2, 2-diphenyl-1-picrylhydrazyl free radical (DPPH) were evaluated. Successive bioassay-guided fractionation was used to elucidate the fraction with higher bioactivity. There was a dose-dependent effect, significant at 20mg/ml of extract on lifespan, fertility and oxidative stress resistance (p < 0.05), but not on learning and memory (Tukey’s post hoc test, n =50 flies/group). Male and female % mean survival time were 6.3±0.7, 4.5±1.4 and 13.6±0.5%, and 4.3±0.4, 12.5±0.4 and 20.7±0.4% respectively. The IC50 value of the extract on DPPH was only three times that of Vitamin C, a known pure antioxidant. The Ethyl Acetate fraction increased stress resistance (p < 0.05), but the sub-fractions obtained did not show any anti-ageing activity at the concentrations tested. The methanol fruit extract of Ananas sativa possesses anti-ageing bioactivity through oxidative stress resistance in Drosophila melanogaster w 1118 flies. Keywords: Longevity; Ananas sativa fractions; antioxidants; DPPH free radical scavenging; oxidative stress; Drosophila melanogaster *Author for correspondence: Email: marta.vicente@uv.es; Tel: +254757128910 4,5 Current addresses Received: November, 2020; Accepted: June, 2020 Abstracted by: Bioline International, African Journals online (AJOL), Index Copernicus, African Index Medicus (WHO), Excerpta medica (EMBASE), CAB Abstracts, SCOPUS, Global Health Abstracts, Asian Science Index, Index Veterinarius INTRODUCTION Ageing is the highest risk factor for non-communicable diseases and disabilities (Beard et al., 2015). Age-related disease burden is on the rise due to accelerated ageing in Sub- Saharan Africa (Gyasi and Phillips, 2019), as a result, 799 deaths per 100,000 population were reported between 1990- 2017 (Bcheraoui et al., 2020). Ageing is a cumulative loss in biological function due to free radical-induced damage to cellular macromolecules (Lopez-Otin et al., 2013). The ability to live longer with minimal physiological decline has remained a challenge, therefore, new approaches into healthy ageing research should be adopted (WHO Report, 2014; Beard et al., 2015). www.ajbrui.org