Bioactive Peptide Fractions from Mung Bean Protein Hydrolysate: Antioxidant Activity, Anti-Inflammatory Effects, and Immunomodulatory Responses in RAW 264.7 Macrophages.

Amid growing concerns over climate change and the need for sustainable agriculture, the study investigated the antioxidant, anti-inflammatory, and immunomodulatory activities of MBPH fractions. MBPH was produced via alcalase hydrolysis and fractionated by ultrafiltration into >5, 3-5, 1-3, and <1 kDa fractions. Bioactivity exhibited a clear inverse correlation with molecular weight. The <1 and 1-3 kDa fractions demonstrated their highest antioxidant capabilities through their performance in ORAC and ABTS tests, which produced results of 836.51 ± 11.81 µmol TE/g and 19.36 ± 0.71 µmol TE/g, respectively. Both fractions also demonstrated significant in vitro anti-inflammatory potential, with the <1 kDa fraction showing superior activity by inhibiting LOX activity (76.93 ± 1.53%) and heat-induced albumin denaturation (81.82 ± 2.72%). All fractions were non-cytotoxic, preserving >90% cell viability in RAW 264.7 macrophages at 100 µg/mL. The 1-3 kDa MBPH fraction exhibited distinct context-dependent immunomodulatory activity in RAW 264.7 macrophages. At 3 h, the fraction markedly suppressed Tnf-α and Il-1β expression under LPS stimulation, indicating strong early-stage anti-inflammatory effects. At 6 h, IL-6 secretion further confirmed this dual behavior, with a mild increase under basal conditions (33.15-36.42 pg/mL) and a reduced level under inflammatory conditions (28.25-28.81 pg/mL). This represents an approximate 15-22% lower IL-6 production technology under LPS stimulation compared to basal conditions at equivalent concentrations. The results demonstrate that low-molecular-weight MBPH peptides, particularly the 1-3 kDa fraction, exhibit dual functionality by providing robust antioxidant protection while dynamically rebalancing immune homeostasis, highlighting their immense potential as bioactive ingredients for functional foods of agroindustry.