Development of a Marine Algae-based Facial Cream Enriched With Phycoerythrin: Physicochemical Properties and Biological Activities.

Phycoerythrin (PE), a marine phycobiliprotein derived from Hypnea valentiae, was extracted, characterized, and evaluated for its potential application in a topical cosmeceutical formulation. The extraction yielded 6.35 mg/g (wet biomass), and spectral analysis confirmed pigment integrity. PE exhibited strong antioxidant activity, with DPPH radical scavenging increasing from 32.4% to 78.6% (20-100 µg/mL) and an IC₅₀ of 46.8 µg/mL, while the ABTS assay showed an IC₅₀ of 41.3 µg/mL. Anti-inflammatory activity revealed IC₅₀ values of 52.1 µg/mL (PE extract) and 60.5 µg/mL (PE cream), compared to 46.6 µg/mL for diclofenac sodium. Antimicrobial analysis demonstrated concentration-dependent activity. HV-PE showed moderate inhibition, whereas the PE-infused cream exhibited enhanced efficacy, with zones of inhibition up to 1.77 cm (Staphylococcus aureus), 1.81 cm (Bacillus subtilis), 1.96 cm (Escherichia coli), and 2.11 cm (Staphylococcus epidermidis) at 1000 µg/mL. MIC/MBC values further confirmed improved antibacterial performance of the cream (e.g., S. aureus: 52.34/46.21 µg/mL) compared to HV-PE. The formulated cream showed suitable physicochemical properties, with pH 7.12 (control: 7.48) and improved spreadability (80.71 g·cm/s vs. 74.79 g·cm/s). The SPF increased from 12.08 (control) to 24.04 (PE cream). Zebrafish toxicity studies indicated no observable adverse effects, confirming biocompatibility. Overall, PE demonstrates significant antioxidant, anti-inflammatory, antimicrobial, and photoprotective properties, supporting its application as a multifunctional cosmeceutical ingredient.