Abstract

Mega Sari Juane Sofiana, Anthoni B Aritonang, Ikha Safitri, Shifa Helena, Syarif Irwan Nurdiansyah, Risko, Dzul Fadly, Warsidah

Several health conditions, including aging, joint inflammations, cancer, and the decrease of organ function related to oxidation, have encouraged the investigation of antioxidants' natural sources. Seaweed is one of the marine commodities that has become the focus of researchers, particularly in correlation to health, such as medicines, functional food, and cosmetics. Euchema spinosumis a red macroalga naturally thrives in Lemukutan coastal, West Kalimantan. This research measured the proximate composition, phytochemical, total phenol content, and determined the antioxidant activity in vitro from the ethanol extract of E. spinosum. Proximate measurements, such as protein was carried out using the micro-Kjeldahl method, fat by the non-polar n-hexane solvent extraction method, and carbohydrate determined using by different calculations. The phytochemicals were identified by reacting to the ethanol extract of E. spinosum. The total phenol was determined spectrophotometrically using gallic acid as a positive control. The antioxidant activity was identified by the DPPH free radical scavenging method. The results showed the proximate was composed of 6.00 % carbohydrates, 0.82% fat, and 1.09 % protein. The ethanol extract of E. spinosumcontained phytochemical components of alkaloids, steroids, tannins, saponins, and flavonoids. The total phenol content of 16.47 ± 0.14 % GEA with the ability to inhibit free radicals (IC50) by 90.10 ppm was classified as a strong antioxidant.