Evaluation of antimicrobial, antioxidant and cytotoxicity potential of R-phycoerythrin extracted from Gracilaria corticata seaweed

In the present study, phycoerythrin pigment protein was extracted and purified from Gracilaria corticata (marine macroalga). The concentration of phycoerythrin (PE) obtained from G. corticata was 0.15 ​mg/ml (fresh weight). In this study, phycoerythrin expressed less antimicrobial activity against pathogens but found effective in total antioxidant activity (264.90 ​± ​10.20 ​μg/ml), DPPH scavenging effect (22.91 ​± ​1.90%) and ferrous ion chelating ability (26.06 ​± ​1.60%). Further, the cytotoxicity assay of PE using colon cancer cells such as SW620 and HCT-116 was tested. Different concentrations (2, 4, 8, 16, 32 ​μl) of phycoerythrin was tested in MTT assay after 24 ​h and 48 ​h incubation. The MTT assay concludes that increasing concentration of phycoerythrin (4.8 ​μg) decreases the cell viability to 42% after 48 ​h in SW 620 ​cell line. Whereas in the HCT 116 ​cell line the increasing concentration of phycoerythrin induces the cell growth on 24 ​h but later drastically reduced growth of cell line (39%) was observed after 48 ​h time in 4.8 ​μg of PE. From this preliminary study, the phycoerythrin pigment extracted from Gracilaria corticata proved to be a potential molecule of interest for cancer studies and diagnosis.