Comparative evaluation of phenolics, flavonoids, and antioxidant activity of aqueous and methanolic extracts of <i>Ananas comosus</i> (pineapple) flesh

Abstract

Abstract. Adefuye AO, Adegbesan BO, Ezima EN, Adefuye TA, Abisoye SB, Bello TH, Ogunbiyi EB, Onasanya AS, Oladeinde TE. 2026. Comparative evaluation of phenolics, flavonoids, and antioxidant activity of aqueous and methanolic extracts of Ananas comosus (pineapple) flesh. Asian J Trop Biotechnol 23 (1): c230102. https://doi.org/10.13057/biotek/c230102. This research investigated the proximates of Ananas comosus Flesh (ACF), Total Phenolic Contents (TPC), Total Flavonoid Contents (TFC), and antioxidant activity of ACF extracts based on Ferric Reducing Antioxidant Potential (FRAP), 2,2’-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS), and Nitric Oxide Scavenging Ability (NOSA). Ten fresh and ripe A. comosus fruits were collected, identified, authenticated, processed to a constant weight, macerated, and decanted to obtain clear filtrates of Methanolic Extract of ACF (MEACF) and Aqueous Extract of ACF (AEACF). Proximate analysis of ACF was conducted based on the standard procedure. Data analysis was conducted by two-way Analysis of Variance (ANOVA) followed by Duncan’s post-hoc test; values with p<0.05 were considered significantly different. Fresh weight of ACF contained 81.00±1.00% moisture, 3.00±0.00% ash, 0.65±0.15% fats, 1.50±0.50% crude fiber, 1.75±0.05% protein, and 12.10±0.30% carbohydrates. AEACF and MEACF exhibited a significant (p<0.05) increase in TPC, TFC, FRAP, and ABTS assays by increasing concentration from 5 µg/mL to 100 µg/mL. AEACF had significantly (p<0.05) higher TPC than MEACF at 5, 10, and 25 µg/mL. At 50 and 100 µg/mL, TPC in MEACF was substantially (p<0.05) higher than in AEACF. At 5, 25, and 100 µg/mL, AEACF showed considerably (p<0.05) higher FRAP values than MEACF. At 10, 25, and 50 µg/mL, AEACF considerably (p<0.05) showed higher scavenging of ABTS radicals than MEACF. At 10 and 25 µg/mL, the NOSA of AEACF was substantially (p<0.05) greater than that of MEACF, whereas at 5 µg/mL, the NOSA of MEACF was substantially (p<0.05) greater than that of AEACF. Increased FRAP values and ABTS radical-scavenging ability indicate higher antioxidant activity, whereas increased nitrite concentration corresponds to lower scavenging activity. Correlation analysis (r=0.964-0.999) demonstrates a strong correlation between TPC, TFC, and in vitro antioxidant parameters. The findings highlight the importance of solvent selection in phytochemical extraction and show that solvent polarity significantly influences the extraction of beneficial chemicals from ACF. Pineapple (A. comosus) may be beneficial for health due to its potentially beneficial components.