Zidan Armanda, Yunita Eka Puspitasari, Dinia Rizqi Dwijayanti, Pamungkas Rizki Ferdian, Zahrotul Firdaus, Heder Djamaludin
Spirulina platensis (Arthrospira platensis) is a protein-rich microalga widely recognized for its nutritional value; however, the bioactivity of its native proteins is limited. This study aimed to investigate whether bromelain-assisted enzymatic hydrolysis could enhance the antioxidant, antibacterial, and anti-inflammatory activities of S. platensis proteins. Proteins were extracted by freeze–thawing and sonication, followed by bromelain-mediated hydrolysis at pH 7 and 65 °C for 4 h. The resulting hydrolysates were characterized in terms of yield, degree of hydrolysis, molecular weight distribution, amino acid composition, and functional groups using standard analytical techniques. Bioactivities were assessed through ferric reducing antioxidant power (FRAP), disk diffusion antibacterial assays against Staphylococcus aureus and Escherichia coli, protein denaturation inhibition, and lipopolysaccharide-induced nitric oxide production in RAW 264.7 macrophage cells. The hydrolysis process yielded low-molecular-weight peptides (≤15 kDa) with an increased degree of hydrolysis and protein content compared to the crude extract. The protein hydrolysates exhibited measurable ferric reducing activity in the FRAP assay; however, their antioxidant reducing power was lower than that of the crude protein extract and therefore considered moderate rather than enhanced. In contrast, the hydrolysates demonstrated enhanced antibacterial activity compared with the non-hydrolyzed protein. In anti-inflammatory assays, the hydrolysates significantly inhibited protein denaturation and suppressed nitric oxide production in a concentration-dependent manner while maintaining high cell viability. These findings indicate that bromelain-assisted hydrolysis effectively enhances the bio-functional properties of S. platensis proteins. Thus, S. platensis protein hydrolysates show potential as natural sources of multifunctional bioactive compounds for food and biomedical applications. © 2026, Walailak University. All rights reserved.
Fish Product Technology Study Program, Faculty of Fisheries and Marine Science, Universitas Brawijaya, East Java, Malang, 65145, Indonesia; Department of Biology, Faculty of Mathematics and Natural Sciences, Universitas Brawijaya, East Java, Malang, 65145, Indonesia; Research Center for Applied Zoology, National Research and Innovation Agency, BRIN, West Java, Cibinong, 16911, Indonesia; Department of Aquatic Product Technology, Faculty of Fisheries and Marine Sciences, IPB University, West Java, 16680, Indonesia
