Comparative Study of Phytochemical Composition and Bioactivities of Different Parts of Alocasia macrorrhizos

This study investigated the phytochemical composition, antioxidant activity, and antibacterial properties of crude extracts obtained from the leaves, leaf stalk and roots of giant taro (Alocasia macrorrhizos). The antibacterial activity was evaluated against Escherichia coli, Pseudomonas aeruginosa, Serratia marcescens, Bacillus cereus, Bacillus subtilis and Staphylococcus aureus. Phytochemical analyses focused on determining the total flavonoid and phenolic contents of each extract. The results revealed that the leaf extract contained the highest concentrations of flavonoids and phenolic compounds, with values of 2.47 mg quercetin equivalents per gram of extract and 85.62 mg gallic acid equivalents per gram of extract, respectively. Antioxidant capacity, assessed using the DPPH radical scavenging assay, showed that the leaf extract exhibited the strongest antioxidant activity, with an IC50 value of 1.34 mg/ml. Furthermore, antibacterial assays indicated that the leaf extract demonstrated the most effective inhibitory activity against all tested bacterial strains, exhibiting lower minimum bactericidal concentrations than the leaf stalk and root extracts. These findings suggest that the leaves of A. macrorrhizos are a rich source of phenolic and flavonoid compounds with significant antioxidant and antibacterial potential, supporting their potential application as natural bioactive agents in pharmaceutical and nutraceutical formulations.