Extraction of Pigments and Antioxidant Activity from the Red Macroalgae Eucheuma cottonii

Abstract

Indonesia is one of the world's significant producers of seaweed and marine macroalgae, accounting for 38% of the global seaweed market. Marine macroalgae contain natural pigments such as chlorophyll, carotenoids, phycoerythrin, and phycobilin, which have the potential as antioxidant, anti-inflammatory, and antimicrobial agents. However, pigment extraction and antioxidant analysis of the red macroalga Eucheuma cottonii have not been reported. Therefore, this study aimed to investigate pigment extraction from E. cottonii and analyze the potential antioxidant compounds. The extraction was conducted using a phosphate buffer solution at a ratio of 1:10 (b/v). The mixture was ultrasonicated at 3,000 and 3,600 rpm and various times (10, 20, and 30 min). The results showed that phycoerythrin concentration increased during ultrasonication at a lower frequency of 3,000 rpm. The crude extract of phycoerythrin (PE) increased from 201.66 to 306.68 μg/mL when ultrasonication was increased from 0 to 30 min. Interestingly, in a shorter time (10 min extraction), the extraction using ultrasonication produced a higher concentration of phycoerythrin than the control, which was carried out without ultrasonication.