Comparative proteomics of whey proteins: New insights into quantitative differences between bovine, goat and camel species

Novel insights into whey protein among Yak, Yellow Cattle, and Cattle-Yak milk

This study identified characteristic whey proteins from Zhongdian Yak (ZY), Diqing Yellow Cattle (DYC), and Cattle Yak (CY), revealing insights into their potential functions and released peptides. A total of 118 whey proteins were quantified in milk obtained from the three breeds of cattle, including seven characteristic proteins (IGL@ protein, 40S ribosomal protein S9, calreticulin, etc.) in CY milk and two characteristic proteins (RNA helicase and uncharacterized protein (A0A3Q1LFQ2)) in ZY milk. These characteristic proteins are involved in the phagosome and Fc gamma R-mediated phagocytosis pathways, exhibiting immunoprotective activities, verified through molecular docking. Furthermore, the molecular docking results showed five whey proteins (IGL@ protein, rho GDP-dissociation inhibitor 1, small monomeric GTPase, action-like protein 3, and adenylyl cyclase-associated protein) interacted with TLR4 through multiple hydrogen and hydrophobic bonds. Therefore, these proteins may exert immunomodulatory functions by inhibiting TLR4. Meanwhile, whey proteins produced bioactive peptides, such as antioxidant peptides and ACE inhibitory peptides after simulated gastrointestinal digestion (SGID). The whey proteins and bioactive peptides from CY exhibited more types and activities than the ZY and DYC whey proteins. This study provides a theoretical basis for promoting formula milk powder production.

Invited review: Camel milk and gut health-Understanding digestibility and the effect on gut microbiota

Camel milk (CM), known for its immune-regulatory, anti-inflammatory, antiapoptotic, and antidiabetic properties, is a natural healthy food. It is easily digestible due to the high levels of β-casein and diverse secreted antibodies, exhibiting superior antibacterial and antiviral activities compared with bovine milk. β-casein is less allergic and more digestible because it is more susceptible to digestive hydrolysis in the gut; therefore, higher levels of β-casein make CM advantageous for human health. Furthermore, antibodies help the digestive system by destroying the antigens, which are then overwhelmed and digested by macrophages. The connection between the gut microbiota and human health has gained substantial research attention, as it offers potential benefits and supports disease treatment. The gut microbiota has a vital role in regulating the host's health because it helps in several biological functions, such as protection against pathogens, immune function regulation, energy harvesting from digested foods, and reinforcement of digestive tract biochemical barriers. These functions could be affected by the changes in the gut microbiota profile, and gut microbiota differences are associated with several diseases, such as inflammatory bowel disease, colon cancer, irritable bowel disorder, mental illness, allergy, and obesity. This review focuses on the digestibility of CM components, particularly protein and fat, and their influence on gut microbiota modulation. Notably, the hypoallergenic properties and small fat globules of CM contribute to its enhanced digestibility. Considering the rapid digestion of its proteins under conditions simulating infant gastrointestinal digestion, CM exhibits promise as a potential alternative for infant formula preparation due to the high β-/αs-casein ratio and protective proteins, in addition to the absence of β-lactoglobulin.

Label-free-based proteomic analysis reveals differential whey proteins of porcine milk during lactation

In this study, label-free proteomic technology was applied to analyze and compare the whey proteomes of porcine colostrum and mature milk. In total, 2993 and 2906 whey proteins were detected in porcine colostrum and mature milk, respectively. A total of 2745 common proteins were identified in the two milk samples, and 280 proteins were found to be significantly differentially expressed whey proteins in porcine milk. Gene Ontology analysis demonstrated that the differentially expressed whey proteins were primarily enriched in lipid homeostasis, oxidoreductase activity, and the collagen trimer. Kyoto Encyclopedia of Genes and Genomes analysis suggested that the phagosome and endocytosis were the crucial pathways. This study provides systematic and in-depth insight into the compositions and functional properties of whey proteins in porcine milk during different periods of lactation, which may be beneficial for the development of porcine whey proteins in the future.

Proteomic Comparisons of Caprine Milk Whole Cream Buttermilk Whey and Cheese Whey Cream Buttermilk

Buttermilk, a potential material used to produce milk fat globule membrane (MFGM), is obtained as a byproduct of butter making from milk whole cream and cheese whey cream. This study investigated the effects of rennet and acid coagulation on the protein profiles of buttermilk rennet-coagulated whey (BRW) and buttermilk acid-coagulated whey (BAW). They were compared to those of whey cream buttermilk (WCB). Rennet coagulation was more efficient in removing casein, while retaining more IgG and lactoferrin than acid coagulation. BRW had more MFGM than BAW. Butyrophilin, xanthine dehydrogenase, and mucin1 were significantly higher (P < 0.05) in BRW, while fatty acid-binding protein 3 was enriched in BAW. KEGG analysis showed that complement and coagulation cascades had the greatest differences, and the abundance of proteins involved in this signaling pathway in BRW and BAW was higher, suggesting their potential anticoagulant and anti-inflammatory activity. BAW had higher apolipoprotein A4 and transcobalamin 2, which are essential carriers for transporting long-chain fatty acids and vitamin B12 from the intestine to the blood. Therefore, BAW intake might improve lipids and vitamin B12 absorption. This study can help deepen the understanding of protein composition of MFGM-enriched whey and facilitate the production of MFGM proteins for infants and old-aged populations.

A comparison of milk fat globule membranes and whey proteomes: New insight into variation nutrient differences between Buffalo, Cow, Goat, and Yak

In this study, the whey and milk fat globule membrane (MFGM) proteomes of buffalo, cow, goat, and yak milk were analyzed using label-free proteomic technology. Totally, 1,292 MFGM proteins and 686 whey proteins were identified from these four species, and GO analysis revealed there were specific proteins with different functions in both whey (376) and MFGM (982) proteomes. The principal component analysis showed that ALB, TF, CSN1S1, and GLYCAM1 are characteristic markers of the milk for each of the four species. Furthermore, the conserved and differential in the expression of whey and MFGM proteins across the four species were identified by limma, and subsequent KEGG pathway analysis showed that immune-related proteins are both conserved and species-specific in the four species. These results provide a deepening of the understanding of the characteristics of proteins in whey and MFGMs from these four common dairy animals and new insight into developing dairy production.