Potential antimicrobial activity of camel milk as a traditional functional food against foodborne pathogens in vivo and in vitro

Foodborne pathogens are a leading cause of mortality worldwide. Therefore, strategies focused on functional foods are urgently required to tackle this issue. As a result, camel milk is one of the most important traditional functional foods since it contains a variety of bioactive components, which all have antimicrobial activity against foodborne pathogens. The study aims to investigate the potential antimicrobial activity of raw camel milk against foodborne pathogens in both in vitro agar well diffusion and infected mice, especially Listeria monocytogenes, Staphylococcus aureus, Salmonella Typhimurium and Escherichia coli, particularly in societies that rely on consuming camel milk in its raw form. A total of eighty C57BL/6 mice were divided into ten groups and gavaged with or without camel milk for two consecutive weeks. A blood plasma analysis and serum insulin levels were measured. Histological investigations of the liver, pancreas, kidney, spleen, lung and testicles were also performed. In both in vivo and in vitro studies when compared to other pathogenic bacteria, E. coli was the most affected by raw camel milk, with a significant clear zone of 2.9 ± 0.13 cm in vitro and in all measured parameters in vivo (p < 0.05). As a result, we advocated for further research to improve camel breeding, raise milk yield and extend its reproductive capability as one of the most important farm animals.

Antibacterial, Antifungal, and Anticancer Effects of Camel Milk Exosomes: An In Vitro Study

Camel milk (CM) has potent antibacterial and antifungal effects and camel milk exosomes (CM-EXO) have been shown to inhibit the proliferation of a large variety of cancer cells including HepaRG, MCF7, Hl60, and PANC1. However, little is known regarding the effects of CM-EXO on bacteria, fungi, HepG2, CaCo2, and Vero cells. Therefore, this study aimed to evaluate the antibacterial, antifungal, and anticancer effects of CM-EXO. EXOs were isolated from CM by ultracentrifugation and characterized by transmission electron microscope and flow cytometry. Unlike CM, CM-EXO (6 mg/mL) had no bactericidal effects on Gram-positive bacteria (Staphylococcus aureus, Micrococcus luteus, and Enterococcus feacalis) but they had bacteriostatic effects, especially against Gram-negative strains (Escherichia coli, Pseudomonas aeruginosa, and Proteus mirabilis), and fungistatic effects on Candida albicans. HepG2, CaCo2, and Vero cells were respectively treated with CM-EXOs at low (6.17, 3.60, 75.35 μg/mL), moderate (12.34, 7.20, 150.70 μg/mL), and high (24.68, 14.40, 301.40 μg/mL) doses and the results revealed that CM-EXOs triggered apoptosis in HepG2 and CaCo2 cells, but not in normal Vero cells, as revealed by high Bax expression and caspase 3 activities and lower expression of Bcl2. Interestingly, CM-EXOs also induced the elevation of intracellular reactive oxygen species and downregulated the expression of antioxidant-related genes (NrF2 and HO-1) in cancer cells but not in normal cells. CM-EXOs have antibacterial and antifungal effects as well as a selective anticancer effect against HepG2 and CaCo2 cells with a higher safety margin on normal cells.

Prospective Role of Bioactive Molecules and Exosomes in the Therapeutic Potential of Camel Milk against Human Diseases: An Updated Perspective

Camel milk (CM) constitutes an important dietary source in the hot and arid regions of the world. CM is a colloidal mixture of nutritional components (proteins, carbohydrates, lipids, vitamins, and minerals) and non-nutritional components (hormones, growth factors, cytokines, immunoglobulins, and exosomes). Although the majority of previous research has been focused on the nutritional components of CM; there has been immense interest in the non-nutritional components in the recent past. Reckoning with these, in this review, we have provided a glimpse of the recent trends in CM research endeavors and attempted to provide our perspective on the therapeutic efficacy of the nutritional and non-nutritional components of CM. Interestingly, with concerted efforts from the research fraternities, convincing evidence for the better understanding of the claimed traditional health benefits of CM can be foreseen with great enthusiasm and is indeed eagerly anticipated.

Comparison of Ethanol Stability and Chemical Composition of Camel Milk from Five Samples

This research was carried out to study the variation in ethanol stability and chemical composition of five camel milk samples, including two pasteurized samples (Alwatania and Darir alabaker) and three raw samples (Majaheim, Wadah, and Hamra). Ethanol stability was analyzed by dispersing camel milk samples with 0 to 100% ethanol (v/v). The findings indicate that camel milk samples precipitated after adding an equal volume of ethanol at concentrations between 50% and 64% ethanol, depending on the milk sample. The addition of sodium chloride at different concentrations (1−10%) to camel milk resulted in a significant increase in ethanol stability, and samples from Majaheim and Alwatania exhibited the highest ethanol stability values (88%). In contrast, the addition of EDTA to camel milk for pH ranging between 5.9 and 7.1 has increased ethanol stability with a sigmoidal shape in camel milk. The largest ethanol stability differences were observed in a camel milk sample from Alwatania. Thus, the level of Ca2+ in camel milk may contribute to ethanol stability by shifting the entire profile to higher ethanol stability values. The chemical composition of different camel samples was also determined. The lactose content of camel milk varied significantly (p < 0.05) across samples, ranging from 4.37% in Majaheim camel milk to 4.87% in Alwatania camel milk. The total solids of camel milk varied significantly between raw and pasteurized samples, ranging between 10.17% and 12.10%. Furthermore, protein concentration in camel milk obtained from different camel samples varied, from 2.43% to 3.23% for Hamra and Alwatania, respectively. In conclusion, ethanol stability in camel milk was dependent on the camel breed, pH level, ionic strength, and EDTA addition.

A state-of-art review on camel milk proteins as an emerging source of bioactive peptides with diverse nutraceutical properties

The generation of camel milk derived bioactive peptides (CM-BAPs) have started to grab keen interest of many researchers during the past decade. CM-BAPs have shown more significant bioactive properties in comparison to camel milk intact proteins. CM-BAPs can be obtained using enzyme hydrolysis to form hydrolysates, or by the fermentation process. In this systematic review, 46 research articles exploring the health-related bioactive properties of CM-BAPs through in-vitro and in-vivo studies have been included. CM-BAPs have been reported for their antioxidant, anti-diabetic, anti-obesity, antihypertensive, antibacterial, antibiofilm, anticancer, anti-inflammatory, anti-haemolytic, and anti-hyperpigmentation activities. The effects of factors such as molecular weight of peptides, type of enzyme, enzyme to substrate ratio, hydrolysis temperature and duration have been analysed. The in-vitro studies have provided enough evidence on certain aspects of the pharmacological actives of camel milk bioactive peptides. Nevertheless, the in-vivo studies are very limited, and no clinical studies on CM-BAPs have been reported.

Research Development on Anti-Microbial and Antioxidant Properties of Camel Milk and Its Role as an Anti-Cancer and Anti-Hepatitis Agent

Camel milk is a rich source of vitamin C, lactic acid bacteria (LAB), beta-caseins and milk whey proteins, including lactoferrin, lysozyme, lactoperoxidase, alpha-lactalbumin and immunoglobulin. The lactoferrin plays a key role in several physiological functions, such as conferring antioxidant, anti-microbial and anti-inflammatory functions in cells. Similarly, the camel milk alpha-lactalbumin has shown greater antioxidative activity because of its higher antioxidant amino acid residues. The antioxidant properties of camel milk have also been ascribed to the structural conformation of its beta-caseins. Upon hydrolysis, the beta-caseins lead to some bioactive peptides having antioxidant activities. Consequently, the vitamin C in camel milk has a significant antioxidant effect and can be used as a source of vitamin C when the climate is harsh. Furthermore, the lysozyme and immunoglobulins in camel milk have anti-microbial and immune regulatory properties. The LAB isolated from camel milk have a protective role against both Gram-positive and -negative bacteria. Moreover, the LAB can be used as a probiotic and may restore the oxidative status caused by various pathogenic bacterial infections. Various diseases such as cancer and hepatitis have been associated with oxidative stress. Camel milk could increase antiproliferative effects and regulate antioxidant genes during cancer and hepatitis, hence ameliorating oxidative stress. In the current review, we have illustrated the anti-microbial and antioxidant properties of camel milk in detail. In addition, the anti-cancer and anti-hepatitis properties of camel milk have also been discussed.