Phytochemical screening and antioxidant activities of Methanol extracts from eight Syzygium species

Abstract

This study was carried out to investigate the phytochemical screening of the methanol crude extracts of the leaves, twigs, and heartwoods of eight Syzygium species (S. filiforme var. filiforme, S. papillosum, S. griffithii, S. pseudoformosum, S. claviflorum var. claviflorum, S. glaucum, S. syzygioides, and Eugenia Sp. 57). The analysis revealed the presence of alkaloids, flavonoids, phenols, steroids, terpenes, and tannins except saponins in all plant extracts. Evaluation of the antioxidant activities were tested using DPPH, FRAP, and ABTS assays. All plant extracts showed good DPPH scavenging activity with the percentage inhibition more than 70 % at 100 ppm. The leaves and twigs of the methanol extracts of S. griffithii exhibited the most potent ferric ion reducer ranging from 1.03 ± 0.03 mM to 7.52 ± 0.49 mM and 1.43 ± 0.12 mM to 9.68 ± 0.38 mM FRAP equivalent, respectively. The heartwoods crude extract of S. syzygioides showed the most potent ferric ion reducer ranging from 1.20 ± 0.01 mM to 10.47 ± 0.12 mM FRAP equivalent. All of the leaves crude extracts showed potential antioxidant activities towards ABTS assay. The methanol extracts of the leaves of S. glaucum showed good SC50 value (116.90 mM) followed by S. papillosum (S2LM, SC50 value = 132.70 mM) and Eugenia Sp. 57 (S4LM, SC50 value = 143.10 mM). The twigs crude extracts of S. syzygioides (S8TM) and S. griffithii (S3TM) showed excellent antioxidant activity towards ABTS assay with the SC50 values of 130.60 mM and 145.40 mM, respectively. The crude extracts of S. syzygioides exhibited good antioxidant activity among the heartwoods extracts with the SC50 value of 96.20 mM.