Dairy peptides and plant polyphenols attract significant attention for their bioactive properties; however, the synergistic antioxidant mechanism of buttermilk peptides and myricetin remains unclear. In this study, buttermilk proteins from Lacprodan MFGM-10, a milk fat globule membrane (MFGM)-enriched buttermilk powder, were subjected to multi-enzyme hydrolysis using papain (Pap), alkaline protease (AP), and neutral protease (NP) at an enzyme concentration of 6000 U/g in different combinations. The results showed that the synergistic application of enzymes significantly increased the degree of hydrolysis (DH), with the AP group reaching a peak DH of approximately 42% at 150 min. Two candidate peptides, WGSPP and SWPWQ, were selected from the screened buttermilk peptide fractions. Through Caco-2 transmembrane transport validation and molecular docking, it is confirmed that these peptides can non-competitively bind to acetylcholinesterase (AChE) via molecular docking, with binding energies of -12.7 and -11.1 kcal/mol, respectively. Additionally, myricetin exhibits a strong binding energy, with a binding energy of -9.5 kcal/mol. In an L6 myoblast injury model induced by rotenone, combined treatment significantly enhances AChE inhibitory rate, reduces reactive oxygen species (ROS) and malondialdehyde (MDA) levels, restores superoxide dismutase (SOD) activity and the NAD+/NADH ratio, and improves mitochondrial membrane potential and ATP levels, without demonstrating cytotoxicity. Buttermilk-derived peptides and myricetin exert synergistic antioxidant effects by improving redox homeostasis and mitochondrial function, thereby alleviating oxidative stress-induced injury in rotenone-induced L6 cells. These findings provide preliminary evidence for the potential role of these compounds in oxidative stress-associated skeletal muscle health; however, direct sarcopenia-related endpoints were not evaluated in the present study.
Wenjing Niu, Xiao-Lin Liu, Jiexia Bai et al.· Journal of Food Science· 0 citations
Whey protein isolate (WPI) is a promising carrier for bioactive compounds, yet its application for muscle health requires further investigation. This study constructed a WPI‐Quercetin (Que) complex using the pH‐shift method and evaluated its binding mechanism, structural evolution, and mitigating effects on dexamethasone (DEX)‐induced muscle damage. The complex achieved optimal stability at a 1:40 Que: WPI mass ratio, characterized by a sulfhydryl (SH) content of 5.94 μmol/g, a particle size of 427 nm, a Polydispersity Index (PDI) of 0.28, and a zeta potential of −32.1 mV. Multispectral analysis and molecular docking suggested that Que primarily embeds into the hydrophobic cavity of WPI through hydrophobic interactions and hydrogen bonds, inducing protein secondary structure rearrangement. In vitro experiments using C2C12 myotube models demonstrated that the WPI‐Que complex significantly enhanced myosin heavy chain (MHC) expression, increased myotube diameter, and improved the fusion index, both in the presence and absence of DEX stimulation. Furthermore, RT‐qPCR and Western blot analyses indicated that the WPI‐Que complex upregulates myogenic regulators more effectively than WPI or Que alone. These findings indicate that the WPI‐Que complex possesses both structural stability and biological activity, offering a theoretical foundation for developing novel functional food ingredients to counteract muscle decline.
Jie-Cheng Bai, Wenjing Niu, Anqi Hu et al.· Journal of food process engi...· 0 citations
Inonotus hispidus polysaccharides (IHP) from this edible medicinal fungus exhibit notable immunological benefits, yet fraction specific effects on host immunity and the gut microbiota remain unclear. This study investigated the differential bioactivities of three graded ethanol-precipitated fractions (IHP-65, IHP-75, and IHP-85) in a cyclophosphamide (CTX)-induced immunosuppressed mouse model. Structural characterization revealed that IHP-65 was a 1098 kDa complex heteropolysaccharide, whereas IHP-85 comprised a highly uniform 19.7 kDa glucan core. Following oral administration, all fractions mitigated CTX induced weight loss, significantly increased spleen and thymus indices, and restored IL-2 and TNF-α toward normal levels. Efficacy was strictly fraction dependent, with the low molecular weight IHP-85 consistently outperforming IHP-75 and IHP-65. Microbiota analysis showed a marked reversal of CTX induced dysbiosis, significantly expanding Bacteroidetes and Firmicutes while suppressing Proteobacteria. At the genus level, Alistipes and Lactobacillus rose and Alloprevotella declined, collectively tracking a recovery trajectory toward the normal control community. These findings demonstrate distinct structure activity relationships among IHP fractions, establishing a clear mechanistic framework for utilizing specific low molecular weight glucans as functional food ingredients to modulate host health via the gut immune axis. PRACTICAL APPLICATIONS: This research demonstrates that graded ethanol precipitation is an effective method for isolating high-activity polysaccharides from Inonotus hispidus. Specifically, the fraction precipitated at high ethanol concentrations shows superior potential for boosting immunity and regulating gut health. These findings provide a scientific basis for food manufacturers to optimize processing techniques and develop effective, natural functional food ingredients targeted at immune support.
Ao Jing, Xiaofan Sun, Shuqing Zhou et al.· Journal of Food Science· 0 citations