Proteomic Profiling Comparing the Effects of Different Heat Treatments on Camel (Camelus dromedarius) Milk Whey Proteins

Abstract

Camel milk is consumed in the Middle East because of its high nutritional value. Traditional heating methods and the duration of heating affect the protein content and nutritional quality of the milk. We examined the denaturation of whey proteins in camel milk by assessing the effects of temperature on the whey protein profile at room temperature (RT), moderate heating at 63 °C, and at 98 °C, for 1 h. The qualitative and quantitative variations in the whey proteins before and after heat treatments were determined using quantitative 2D-difference in gel electrophoresis (DIGE)-mass spectrometry. Qualitative gel image analysis revealed a similar spot distribution between samples at RT and those heated at 63 °C, while the spot distribution between RT and samples heated at 98 °C differed. One hundred sixteen protein spots were determined to be significantly different (p < 0.05 and a fold change of ≥1.2) between the non-heated and heated milk samples. Eighty protein spots were decreased in common in both the heat-treated samples and an additional 25 spots were further decreased in the 98 °C sample. The proteins with decreased abundance included serum albumin, lactadherin, fibrinogen β and γ chain, lactotransferrin, active receptor type-2A, arginase-1, glutathione peroxidase-1 and, thiopurine S, etc. Eight protein spots were increased in common to both the samples when compared to RT and included α-lactalbumin, a glycosylation-dependent cell adhesion molecule. Whey proteins present in camel milk were less affected by heating at 63 °C than at 98 °C. This experimental study showed that denaturation increased significantly as the temperature increased from 63 to 98 °C.

Effects of industrial processing methods on camel skimmed milk properties

“…Furthermore, CM whey proteins were also reported to be more sensitive to heat treatments, with denaturation rates faster than those of bovine milk (Felfoul, Lopez, Gaucheron, Attia, & Ayadi, 2015a). Benabdelkamel et al (2017) indicated that heat treatment of CM whey at 98 °C for 60 min caused a significant denaturation of camel α-lactalbumin (α-la), lactoferrin (LF), and serum albumin (SA).…”

Circulating proteomic signature for detection of biomarkers in bladder cancer patients

“…The gels were scanned with a Typhoon 9400 scanner using appropriate wavelengths and filters for Cy2, Cy3 and Cy5. Difference in-gel electrophoresis (DIGE) images were analyzed using the Progenesis SameSpots v.3.3 software (Nonlinear Dynamics Ltd., UK) as described previously 53 . All spots were pre-filtered and manually checked before applying the statistical criteria (ANOVA test, p ≤ 0.05 and fold ≥ 1.5).…”

Comparative Analysis of Milk Fat Globular Membrane (MFGM) Proteome between Saudi Arabia Camelus dromedary Safra and Wadha Breeds

“…The extraction of MFGM was done as described previously [75,76] with some modifications. Briefly, the MFGM pellets were incubated with lysis buffer (pH 8.8, 30 Mm Tris buffer containing 7 M urea, 2 M thiourea, 2% Chaps, 1× protease inhibitor mix), for 1 h with periodic vortexing.…”

“…Coomassie-stained gel spots from the preparatory gel were washed and digested according to previously described methods [76][77][78]. The mixture of tryptic peptides (1 µL) derived from each protein was spotted onto a MALDI target (384 Anchorchip MTP 800 µm Anchorchip; Bruker Daltonik, Bremen, Germany).…”