AKTIVITAS ANTIOKSIDAN DAN SENYAWA BIOAKTIF EKSTRAK RUMPUT LAUT Halimeda SP.

Abstract

Seaweed is known to have one function as an antioxidant needed by the body to inhibit free radicals. However, synthetic antioxidants are carcinogenic in the long term, so natural antioxidants are needed. This study aimed to determine the bioactive compounds and the strength of the antioxidant activity of Halimeda sp. seaweed extract from Bintan Waters, Riau Islands. The research was conducted for five months, starting with sampling, carried out by sweeping from the Bakau Bay waters to Pengudang Village. Extraction was carried out for 2x24 hours using methanol solvent. Analysis of antioxidant activity in this study used the DPPH method by testing the maximum wave, incubation time, antioxidant activity, and positive control (BHT). The category of antioxidant activity is determined from the  value. Furthermore, an analysis was carried out for the presence of bioactive coumpounds, namely the steroid and triterpenoid test, the saponin test, and the tannin test. The measured of total phenol content and the flavonoid contetent, respectively, used gallic acid and quercetin solutions as standard solutions. The chlorophyll and carotenoids were measured using acetone as a solvent by measuring the absorbance at a wavelength of 663, 645, and 480 nm. The results showed that Halimeda sp. extract has an  value of 221,62 ppm and is classified as very weak antioxidant. This extract contains bioactive coumpounds, namely steroid coumpounds an tannin. The total phenolic content, total flavonoids content, chlorophyll a, clorophyll b, and carotenoids was 26.745 mg GAE/g samples, 5.553 mg QE/g samples, 3.130 mg/g, 4.169 mg/g, and 5.944 µmol/g.