The ethanol extract of the bastard cedar (Guazuma ulmifolia L.) as antioxidants

Guazuma ulmifolia, or commonly known as the bastard cedar, has many pharmaceutical activities and is, therefore, claimed as a source of various plant-based medicines. This reserach was purposed to identify the antioxidant activities of the ethanolic extract of G. ulmifolia (EEGU) by phytochemical screening assay, total flavonoid and total phenolic testing, and comparative analysis between the antioxidant activities of EEGU and epicatechin. The qualitative phytochemical screening assay of EEGU detected the availability of phenols, flavonoids, alkaloids, tannins, and terpenoids, but not saponins and triterpenoids. Meanwhile, the total phenolic content was 32.24 µg GAE/mg extract, and the total flavonoid content decided using aluminum chloride reagent with quercetin standard, was 6.48 µg QE/mg extract. The role of antioxidants examined by FRAP, DPPH, H 2 O 2 , and ABTS assays. These assay are proved that the IC 50 values of EEGU are higher than those of epicatechin. For DPPH scavenging, H 2 O 2 scavenging, and ABTS reduction activities, EEGU resulted IC 50  45.70 μg/mL, 162.93 μg/mL, and 35.96 μg/mL, while epicatechin only yielded IC 50  0.56 μg/mL, 57.91 μg/mL, and 16.74 μg/mL respectively. Otherwise, the highest reduction in FRAP activities were shown at  50 μg/mL concentration  of epicatechin and EEGU were 236.33 and 202.71 µM Fe (II)/µg respectively. Based on these results, EEGU is concluded as an active natural product because it exhibit antioxidant activities.