Characteristics and Antioxidant Activities of Gracilaria sp. Seaweed from Banten

Abstract

The Gracilaria sp. seaweed is often used as a source of commercial agar, however in recent years the price of this seaweed has dropped dramatically. Red seaweed has many health benefits. This study was aimed to determine proximate contains, heavy metal, total phenol and total flavonoid, and antioxidant activity of the seaweed Gracilaria sp. Extraction using the maceration method with ethanol, ethyl acetate, and n-hexane solvents with a ratio of 1:6 had a significant effect (α=0.05) on the antioxidant activity.The highest antioxidant activity was observed fromthe ethanolic extract with IC50 =22.15±1.63 μg/mL (very strong). Qualitative testing of the bioactive components of the ethanol extract of Gracilaria sp. found alkaloids, phenols, saponins, flavonoids, triterpenoids. Tests for total flavonoids and total phenols were carried out using a UV-Vis spectrophotometer obtaining 21.78±0.32 mg QE/g and 124±2.13 mg GAE/g respectively.