Antioxidant Properties of R-Phycoerythrin from Red Alga Spyridia filamentosa (Wulfen) Harvey Collected on the Pudumadam Coast

Abstract

Natural antioxidants are found in algae, are important biologically active compounds that involve in protecting the cells from oxidation thereby used in defense mechanism on ageing processes and various diseases. In this study, R-Phycoerythrin (R-PE) was extracted from Spyridia filamentosa and was assessed for their antioxidant properties. The antioxidising property of decontaminated R-PE has been evaluated by measuring the free radical scavenging activity by DPPH radical scavenging assay, ABTS radical scavenging activity, hydroxyl radical scavenging activity, superoxide radical (O2) scavenging assay, nitric oxide scavenging activity and phosphomolybdenum reduction assay. The purified R-PE extract was subjected to structural analysis by UV-Visible spectroscopy, fluorescence emission spectroscopy and infrared spectroscopy. The UV-Visible spectrum showed a peak at 496 nm, 543 nm and 564 nm and fluorescence emission spectrum of R-PE was measured 575 nm which confirmed the presence of R-Phycoerythrin. The IR spectral data showed the presence of aromatic constituents containing amide group in the protein. DPPH radical scavenging assay showed the highest antioxidant potential with an IC50 value of 128.25 μg/ml. The radical scavenging activity of Nitric oxide showed an IC50 value of 87.85 μg/ml, Phosphomolybdenum reduction assay showed an RC50 value of 61.45 μg/ml. The hydroxyl radical scavenging activity showed IC50 value of 34.56 μg/ml and Superoxide radical (O2) scavenging assay showed IC50 value of 18.58 μg/ml. The ABTS radical scavenging activity showed the lowest antioxidant potential of 3.13 μg/ml. The free radical scavenging property of R-Phycoerythrin (R-PE) concentrate of Spyridia filamentosa demonstrate that it has high antioxidant potency and it could be considered as utilitarian nourishment with essential pharmaceutical and biological importance.