Assessment of different solvents effect on bioactive compounds, antioxidant activity and nutritional formation of red seaweed, Gracilariopsis longissima, from Bay of Bengal, Bangladesh

Seaweed is known to empower a mass embodiment of bioactive compounds with potent health convenience. Current perusals intended to explore the total phenolic content (TPC), total flavonoid content (TFC), and antioxidant dynamism of red seaweed, Gracilariopsis longissima as pervaded by different solvents and solvent fractions (methanol, ethanol, acetone, and water). The extracts dynamism to antioxidant were assessed by 1,1-diphenyl-2-picrylhydrazyl (DPPH), and 2, 2 ’ -Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). Here, 100% methanolic and acetonic extract asserted maximal extent of total phenolic and flavonoid content (88.70 mg of gallic acid/g and 75.06 mg of quercetin/g respectively) in a sufficiently great way. However, 50% methanolic DPPH and ABTS solution (74.32%, IC 50 = 0.027 mg/ml and 70.51%, IC 50 = 0.033 mg/ml) significantly demonstrated the highest percentage of inhibition and antioxidant activity compared to other solvents. Gracilariopsis longissima also contains a high amount of protein (30.63%) and minerals especially potassium (4.47%) and calcium (2.54%). According to the results of this study, G. longissima extracts prepared using 100% methanol as a solvent showed higher total phenolic and total flavonoid quantity and 50% methanol as a solvent showed higher antioxidant potential. These properties will be valuable for nutritional food and medicinal uses.