Extraction, purification, and bioevaluation of phycoerythrin from Halymenia refugium against pathogenic bacteria and A549 lung cancer cell line

Abstract

Lung cancer is still among the most frequent cancer-induced deaths, and the traditional and modern treatment options usually lead to severe side effects and lack effectiveness. In this case, the bioactive properties of phycoerythrin (PE), which was extracted in the red alga Halymenia refugium, were evaluated. It was extracted using freeze-thaw method, and subsequently purified via ion-exchange chromatography. Extraction technique yielded 5.36 mg of the pigment / g of the alga. The qualitative analyses revealed the presence of flavonoids (6.91 mg/g) and phenolics (2.29 mg GAE/g). The antioxidant properties of PE exhibited good scavenging of DPPH (91.2%), ABTS (81.5%), and phosphomolybdate (86.15%). PE was able to inhibit α-amylase by 88.30% (IC₅₀ = 30.81 µg/mL) and β-glucosidase by 91.06% (IC₅₀ = 36.34 µg/mL) and defined its anti-diabetic property. anti-inflammatory activity was successfully investigated and confirmed through total protein denaturation (94.09% inhibition, IC₅₀ = 44.62 µg/mL) and egg albumin denaturation (85.57% inhibition, IC₅₀ = 47.31 µg/mL) assays. Phycoerythrin checked the growth of A549cells to 63.95 % at a specified concentration of 75mM.A good inhibition was observed in bacterial antagonism against S. aureus and B. subtilis. These findings suggested that phycoerythrin from H. refugium exhibited strong antioxidant, antidiabetic, anti-inflammatory, antimicrobial, and cytotoxic potential, supporting its development as a natural multifunctional therapeutic agent.