Characteristics of Brown Seaweeds Sargassum policystum and Padina minor from Pohuwato Water, Gorontalo

Abstract

Brown seaweed is one of the abundant resources that grows on the reefs of Pohuwato, Gorontalo Province. This research was aimed to determine the characteristics of <em>S. polycystum</em> and <em>P. minor</em> as sources of salt for hypertensive patients. The research consisted of proximate analysis, minerals, heavy metals, extraction, phytochemicals, phenols analysis, and antioxidant activity. <em>S. polycystum, P. minor</em> had water content of 17.69-22.31%, ash 24.51-30.53%, fat 0.50-0.52%, protein 3.65-4.78%, carbohydrates 53.66-41.88 and crude fiber 3.81-6.52%. The seaweeds also contained Mg 8.89-22.41 mg/g, Fe 0.50-1.00 mg/g, K 26.90-32.71%, Na 22.23-22.69 mg/g, Ca 18.06-32.91 mg/g and ratio Na:K 0.69-0.83 mg/g. Heavy metals were detected in low levels with the content<0.002-<0.004 ppm. Ethanol extract of S. polycystum contained flavonoid, saponin, streoid, alkaloid. Meanwhile ethanol extract of <em>P. minor</em> contained flavonoid, saponin, triterpenoid, stereoid, phenol, dan alkaloid. Total phenol level of<em> S. polycystum</em> was 173.6 mg GAE/g and <em>P. minor</em> was 568.7 mg GAE/g. The antioxidant IC50 of <em>S. Polycystum</em> was 77.58 mg/L while <em>P. minor</em> was 66.38 mg/L.