Project description:Demand for camel milk (CM) is increasing worldwide, due to its high nutritious value and health benefits. In this study, whole CM powders were produced by spray drying (SD) at six inlet temperatures (190°C - 250°C) and by freeze drying (FD). Physicochemical and functional properties of CM powder proteins were investigated. Both treatments had negative effect on casein solubility, while whey proteins remained soluble and slightly increased its solubility with the extent of MR. The CM powders obtained at higher inlet temperatures demonstrated improved antioxidant activity. Secondary structure of whey proteins did not differ among the samples, while surface hydrophobicity of whey proteins was higher in all SD than in FD samples, suggesting only limited denaturation of camel whey proteins at higher inlet temperatures of drying. Thus, the effects of SD under the conditions applied in our study did not decrease camel whey protein solubility, while drying procedure itself regardless of temperature decreased solubility of camel milk caseins. This study provides useful insights for optimization of CM powder production.
Project description:Camel milk is widely characterized with regard to caseins and whey proteins. However, in camelids, close to nothing is known about the Milk Fat Globule Membrane (MFGM), the membrane surrounding fat globules in milk. The purpose of this study was thus to identify MFGM proteins from Camelus dromedarius milk. Major MFGM proteins (namely, fatty acid synthase, xanthine oxidase, butyrophilin, lactadherin, and adipophilin) already evidenced in cow milk were identified in camel milk using mass spectrometry. In addition, a 1D-LC-MS/MS approach led us to identify 322 functional groups of proteins associated with the camel Milk Fat Globule Membrane. We hope that these findings will contribute to a better characterization of camel milk and to an improved understanding of lipid droplet formation in the mammary epithelial cell.
Project description:Milk fat globule membrane (MFGM) proteins, which are recognized to play a variety of biological roles; nevertheless, their composition and interspecies complexity remain unknown. This study aimed to identify and quantify proteins extracted from MFGM-enriched fractions of bovine, goat and camel milk by a label free proteomics approach. We identified 1579 proteins, substantially increasing the number of MFGM proteins identified for these species. The results of functional analysis showed that the identified MFGM proteins had similar functional annotations, with cellular processes, intracellular anatomical structures and binding being the predominant GO annotations. And most of the proteins were involved in KEGG pathways such as protein processing of ribosomes and endoplasmic reticulum. Subsequently, multiple statistical methods were used to compare the differences in MFGM protein quantification among different species. The results of principal component analysis showed that bovine, goat and camel milk MFGM proteins were significantly different, among which CSN1S1, XDH, LTF and PI4KA played an important role in taxonomic identification. Meanwhile the results of hierarchical clustering showed that the differences (p<0.05) between bovine and goat milk were smaller than those of camel milk. These new data deepen the understanding of the protein composition of MFGM and its possible physiological roles, providing directions for the production of specific functional milk proteins.
Project description:The “ship of the desert”, the one-humped Arabian camel (Camelus dromedarius), has a remarkable capacity to survive in conditions of extreme heat without needing to drink water. One of the ways that this is achieved is through the actions of the antidiuretic hormone vasopressin (AVP) and the natriuretic hormone oxytocin (OXT), both of which are made in a specialised part of the brain called the hypothalamo-neurohypophyseal system (HNS), but exert their effects at the level of the kidney to, respectively, provoke water conservation and salt excretion. Interestingly, our electron microscopy studies have shown that the ultrastructure of the camel HNS changes according to season, suggesting that in the arid conditions of summer the dromedary’s HNS is in a state of permanent activation, in preparation for the likely prospect of water deprivation. Based on our camel genome sequence, we have carried out an RNAseq analysis of the camel HNS in summer and winter.
Project description:Breastfeeding is vital for reducing morbidity and mortality, yet exclusive breastfeeding rates are low, with insufficient milk supply being a major weaning factor whose molecular causes remain largely unknown. In this study, we collected fresh milk samples from 30 lactating individuals, classified as low, normal, or high milk producers at multiple postpartum stages, and conducted extensive genomic and microbiome analysis. Using bulk RNA sequencing on human milk fat globules (MFG), milk cells, and breast tissue, we found that MFG-derived RNA closely resembles RNA from milk luminal cells. Furthermore, bulk and single-cell RNA-seq revealed changes in the transcriptome and cellular content linked to milk production. We identified specific genes and cell-type proportions differing in low and high milk production. Infant microbiome diversity was affected by feeding type, but not by maternal milk supply. This study provides a comprehensive human milk transcriptomic catalog, identifies genes associated with milk production, and highlights MFG as a useful biomarker for milk transcriptome analysis.
Project description:Breastfeeding is vital for reducing morbidity and mortality, yet exclusive breastfeeding rates are low, with insufficient milk supply being a major weaning factor whose molecular causes remain largely unknown. In this study, we collected fresh milk samples from 30 lactating individuals, classified as low, normal, or high milk producers at multiple postpartum stages, and conducted extensive genomic and microbiome analysis. Using bulk RNA sequencing on human milk fat globules (MFG), milk cells, and breast tissue, we found that MFG-derived RNA closely resembles RNA from milk luminal cells. Furthermore, bulk and single-cell RNA-seq revealed changes in the transcriptome and cellular content linked to milk production. We identified specific genes and cell-type proportions differing in low and high milk production. Infant microbiome diversity was affected by feeding type, but not by maternal milk supply. This study provides a comprehensive human milk transcriptomic catalog, identifies genes associated with milk production, and highlights MFG as a useful biomarker for milk transcriptome analysis.
Project description:To investigate the central control of water homeostasis in the dromedary camel, we have performed transcriptomic studies on the supraoptic nucleus samples from camels under control (water ad libitum) and dehydrated (water deprivation for 20 days) conditions by RNA sequencing. We have identified genes that change in expression in response to hyperosmotic challenge and transcriptomic response networks that might be essential for adaptations of camel to live and thrive in aird desert environment.