Impact of quercetin conjugation using alkaline and free radical methods with tandem ultrasonication on the functional properties of camel whey and its hydrolysates.

The structural and functional properties of whey-quercetin and whey hydrolysate-quercetin conjugates synthesized using alkaline and free radical-mediated methods (AM and FRM) coupled with sonication were studied. FTIR showed new peaks at 3000-3500 cm-1 (N-H stretching regions) and the 1000-1100 cm-1 region with the conjugates. Conjugation increased the random coils and α-helix content while decreasing the ß-sheets and turns. It also increased the particle size and surface hydrophobicity which was significantly (p < 0.05) higher in AM than FRM conjugates. AM conjugates had higher radical scavenging activity but lower quercetin content than FRM conjugates. Overall, the functional properties of whey-quercetin conjugates were better than whey hydrolysate-quercetin conjugates. However, hydrolysate conjugates had significantly higher denaturation temperatures irrespective of the method of production. Sonication improved the radical scavenging activity and quercetin content of FRM conjugates while it decreased both for AM conjugates. This study suggested that whey-quercetin conjugates generally had better quality than whey hydrolysate conjugates and sonication tended to further improve these properties. This study highlights the potential for using camel whey or whey hydrolysate-quercetin conjugates to enhance the functional properties of food products in the food industry.

Spray drying and ultrasonication processing of camel whey protein concentrate: Characterization and impact on bioactive properties.

The production of whey protein concentrates (WPCs) from camel milk whey represents an effective approach to valorize this processing by-product. These concentrates harbor active ingredients with significant bioactive properties. Camel WPCs were spray-dried (SD) at inlet temperature of 170, 185 and 200°C, or Ultrasonicated (US) for 5, 10 and 15 min, then freeze-dried to obtain fine powder. The impact of both treatments on protein degradation was studied by sodium dodecyl sulfate-PAGE and reverse-phase ultraperformance liquid chromatography (RP-UPLC) techniques. Significantly enhanced protein degradation was observed after US treatment when compared with SD. Both SD and US treatments slightly enhanced the WPCs samples' antioxidant activities. The US exposure for 15 min exhibited highest 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) scavenging activity (12.12 mmol TE/g). Moreover, US treatment for 10 min exhibited the highest in vitro anti-diabetic properties (α-amylase and α-glucosidase inhibition), and dipeptidyl-peptidase-IV inhibitory activity among all samples. In addition, the ultrasonication for 10 min and SD at 170°C showed the lowest IC50 values for in vitro anti-hypercholesterolemic activities in terms of pancreatic lipase and cholesteryl esterase inhibition. Conclusively, these green techniques can be adapted in the preservation and processing of camel milk whey into active ingredients with high bioactive properties.

Invited review: Camel milk-derived bioactive peptides and diabetes-Molecular view and perspectives.

In dairy science, camel milk (CM) constitutes a center of interest for scientists due to its known beneficial effect on diabetes as demonstrated in many in vitro, in vivo, and clinical studies and trials. Overall, CM had positive effects on various parameters related to glucose transport and metabolism as well as the structural and functional properties of the pancreatic ß-cells and insulin secretion. Thus, CM consumption may help manage diabetes; however, such a recommendation will become rationale and clinically conceivable only if the exact molecular mechanisms and pathways involved at the cellular levels are well understood. Moreover, the application of CM as an alternative antidiabetic tool may first require the identification of the exact bioactive molecules behind such antidiabetic properties. In this review, we describe the advances in our knowledge of the molecular mechanisms reported to be involved in the beneficial effects of CM in managing diabetes using different in vitro and in vivo models. This mainly includes the effects of CM on the different molecular pathways controlling (1) insulin receptor signaling and glucose uptake, (2) the pancreatic ß-cell structure and function, and (3) the activity of key metabolic enzymes in glucose metabolism. Moreover, we described the current status of the identification of CM-derived bioactive peptides and their structure-activity relationship study and characterization in the context of molecular markers related to diabetes. Such an overview will not only enrich our scientific knowledge of the plausible mode of action of CM in diabetes but should ultimately rationalize the claim of the potential application of CM against diabetes. This will pave the way toward new directions and ideas for developing a new generation of antidiabetic products taking benefits from the chemical composition of CM.

Molecular docking studies on α-amylase inhibitory peptides from milk of different farm animals.

Milk-derived peptides have emerged as a popular mean to manage various lifestyle disorders such as diabetes. Fermentation is being explored as one of the faster and efficient way of producing peptides with antidiabetic potential. Therefore, in this study, an attempt was made to comparatively investigate the pancreatic α-amylase (PAA) inhibitory properties of peptides derived from milk of different farm animals through probiotic fermentation. Peptide's identification was carried out using liquid chromatography-quadrupole time-of-flight mass spectrometry and inhibition mechanisms were characterized by molecular docking. Results obtained showed a PAA-IC50 value (the amount of protein equivalent needed to inhibit 50% of enzymes) between 2.39 and 36.1 µg protein equivalent for different fermented samples. Overall, Pediococcus pentosaceus MF000957-derived fermented milk from all animals indicated higher PAA inhibition than other probiotic derived fermented milk (PAA-IC50 values of 6.01, 3.53, 15.6, and 10.8 µg protein equivalent for bovine, camel, goat, and sheep fermented milk). Further, molecular docking analysis indicated that camel milk-derived peptide IMEQQQTEDEQQDK and goat milk-derived peptide DQHQKAMKPWTQPK were the most potent PAA inhibitory peptides. Overall, the study concluded that fermentation derived peptides may prove useful in for managing diabetes via inhibition of carbohydrate digesting enzyme PAA.

Regulation of iron metabolism is critical for the survival of Salmonella Typhimurium in pasteurized milk.

Salmonella is known to survive in raw/pasteurized milk and cause foodborne outbreaks. Lactoferrin, present in milk from all animal sources, is an iron-binding glycoprotein that limits the availability of iron to pathogenic bacteria. Despite the presence of lactoferrins, Salmonella can grow in milk obtained from different animal sources. However, the mechanism by which Salmonella overcomes iron scarcity induced by lactoferrin in milk is not evaluated yet. Salmonella employs the DNA binding transcriptional regulator Fur (ferric update regulator) to mediate iron uptake during survival in iron deplete conditions. To understand the importance of Fur in Salmonella milk growth, we profiled the growth of Salmonella Typhimurium Δfur (ST4/74Δfur) in both bovine and camel milk. ST4/74Δfur was highly inhibited in milk compared to wild-type ST4/74, confirming the importance of Fur mediated regulation of iron metabolism in Salmonella milk growth. We further studied the biology of ST4/74Δfur to understand the importance of iron metabolism in Salmonella milk survival. Using increasing concentrations of FeCl3, and the antibiotic streptonigrin we show that iron accumulates in the cytoplasm of ST4/74Δfur. We hypothesized that the accumulated iron could activate oxidative stress via Fenton's reaction leading to growth inhibition. However, the inhibition of ST4/74Δfur in milk was not due to Fenton's reaction, but due to the 'iron scarce' conditions of milk and microaerophilic incubation conditions which made the presence of the fur gene indispensable for Salmonella milk growth. Subsequently, survival studies of 14 other transcriptional mutants of ST4/74 in milk confirmed that RpoE-mediated response to extracytoplasmic stress is also important for the survival of Salmonella in milk. Though we have data only for fur and rpoE, many other Salmonella transcriptional factors could play important roles in the growth of Salmonella in milk, a theme for future research on Salmonella milk biology. Nevertheless, our data provide early insights into the biology of milk-associated Salmonella.

Valorization of different low-grade date (Phoenix dactylifera L.) fruit varieties: A study on the bioactive properties of polyphenolic extracts and their stability upon in vitro simulated gastrointestinal digestion.

Nowadays, the development of suitable strategies for the management and valorization of agri-food products is one of the most important challenges worldwide. In this context, the current research study aimed to explore a valorization strategy for different varieties (Khalas, Jabri, Lulu, Booman, and Sayer) of low-grade date fruit by extracting polyphenolic compounds and investigating their health-promoting bioactive properties. The generated extracts were comparatively analyzed for their phenolic contents, antioxidant, anti-inflammatory, anti-hemolytic, and enzyme inhibitory activities upon in vitro simulated gastrointestinal digestion (SGID). The total phenolic contents (TPC) ranged from 217.3 to 1846.9 mg GAE/100 g fresh weight. After complete SGID, the TPC remarkably increased from 570.8 mg GAE/100 g fresh weight (undigested), reaching the highest value of 1606.3 mg GAE/100 g fresh weight with the Khalas cultivar. Overall, gastric and complete-SGID-treated extracts exhibited higher antioxidant activities, compared to the undigested extracts for the five selected date varieties. Similarly, the gastric and complete SGID promoted the release of bioactive components endowed with significantly higher inhibition levels towards digestive enzymes related to diabetes. Moreover, extracts from all varieties revealed an increase in the inhibition of lipidemic-related enzymatic markers and anti-inflammatory activities when subjected to the gastric digestion phase, which decreased after complete SGID. Principal component analysis (PCA) suggested that higher bioactive properties were influenced by the TPC present in the samples. Overall, low-quality dates could be considered as a potential source of bioactive polyphenols with interesting nutraceutical properties, released upon their transit through the gastrointestinal tract.

In-depth peptidomic profile and molecular simulation studies on ACE-inhibitory peptides derived from probiotic fermented milk of different farm animals.

Investigations into ACE inhibitory properties of probiotic fermented bovine, camel, goat, and sheep milk were performed and studied for two weeks of refrigerated storage. Results from the degree of proteolysis suggested higher susceptibility of goat milk proteins, followed by sheep and camel milk proteins, to the probiotic-mediated proteolysis. ACE-inhibitory properties displayed continuous decline in ACE-IC50 values for two weeks of refrigerated storage. Overall, goat milk fermented with Pediococcus pentosaceus caused maximum ACE inhibition (IC50: 262.7 µg/mL protein equivalent), followed by camel milk (IC50: 290.9 µg/mL protein equivalent). Studies related to peptide identification and in silico analysis using HPEPDOCK score revealed presence of 11, 13, 9 and 9 peptides in fermented bovine, goat, sheep, and camel milk, respectively, with potent antihypertensive potential. The results obtained suggest that the goat and camel milk proteins demonstrated higher potential for generating antihypertensive peptides via fermentation when compared to bovine and sheep milk.

Metabolomics approach for the identification of bioactive compounds released from young and mature soybean upon in vitro gastrointestinal digestion and their effect on health-related bioactive properties.

The aim of the present study was to comparatively investigate the relative phytochemical profiles (phenolic content, organic and amino acids, free sugars, and other metabolites using metabolomics approach), and bioactive potentials of young (YS) and mature soybean (MS) upon in vitro simulated gastrointestinal digestion (SGID). Cumulatively, a total of 198 metabolites were identified in MS and YS, 119 metabolites in undigested YS, and a total of 136 metabolites in undigested MS, which further increased to 156 and 152 in YS and MS upon SGID, respectively. Gastric digesta of both YS and MS exhibited higher inhibitory properties towards α-amylase and DPP-IV enzymes than their intestinal digesta. Furthermore, the intestinal digesta of MS showed higher antioxidant and anti-inflammatory activities compared to the YS intestinal digesta. Overall, the results suggested that the gastrointestinal digestion of YS and MS displayed distinctive metabolic profiles together with varied bioactive potentials.

In vitro antidiabetic and antihypercholesterolemic activities of camel milk protein hydrolysates derived upon simulated gastrointestinal digestion of milk from different camel breeds.

Milk protein hydrolysates derived from 4 camel breeds (Pakistani, Saheli, Hozami, and Omani) were evaluated for in vitro inhibition of antidiabetic enzymatic markers (dipeptidyl peptidase IV and α-amylase) and antihypercholesterolemic enzymatic markers (pancreatic lipase and cholesterol esterase). Milk samples were subjected to in vitro simulated gastric (SGD) and gastrointestinal digestion (SGID) conditions. In comparison with intact milk proteins, the SGD-derived milk protein hydrolysates showed enhanced inhibition of α-amylase, dipeptidyl peptidase IV, pancreatic lipase, and cholesterol esterase as reflected by lower half-maximal inhibitory concentration values. Overall, milk protein hydrolysates derived from the milk of Hozami and Omani camel breeds displayed higher inhibition of different enzymatic markers compared with milk protein hydrolysates from Pakistani and Saheli breeds. In vitro SGD and SGID processes significantly increased the bioactive properties of milk from all camel breeds. Milk protein hydrolysates from different camel breeds showed significant variations for inhibition of antidiabetic and antihypercholesterolemic enzymatic markers, suggesting the importance of breed selection for production of bioactive peptides. However, further studies on identifying the peptides generated upon SGD and SGID of milk from different camel breeds are needed.

Novel Plant-Protein (Quinoa) Derived Bioactive Peptides with Potential Anti-Hypercholesterolemic Activities: Identification, Characterization and Molecular Docking of Bioactive Peptides.

Hypercholesterolemia remains a serious global public health concern. Previously, synthetic anti-hypercholesterolemic drugs were used for ameliorating this condition; however, long-term usage presented several side-effects. In this regard, natural products as an adjunct therapy has emerged in recent times. This study aimed to produce novel bioactive peptides with anti-hypercholesterolemic activity (cholesterol esterase (CEase) and pancreatic lipase (PL)) from quinoa protein hydrolysates (QPHs) using three enzymatic hydrolysis methods (chymotrypsin, protease and bromelain) at 2-h hydrolysis intervals (2, 4, and 6 h). Chymotrypsin-generated hydrolysates showed higher CEase (IC50: 0.51 mg/mL at 2 h) and PL (IC50: 0.78 mg/mL at 6 h) inhibitory potential in comparison to other derived hydrolysates and intact quinoa proteins. Peptide profiling by LC-MS QTOF and in silico interaction with target enzymes showed that only four derived bioactive peptides from QPHs could bind in the active site of CEase, whereas twelve peptides could bind in the active site of PL. Peptides QHPHGLGALCAAPPST, HVQGHPALPGVPAHW, and ASNLDNPSPEGTVM were identified to be potential CEase inhibitors, and FSAGGLP, QHPHGLGALCAAPPST, KIVLDSDDPLFGGF, MFVPVPH, and HVQGHPALPGVPAHW were identified as potential PL inhibitors on the basis of the maximum number of reactive residues in these bioactive peptides. In conclusion, QPHs can be considered as an alternative therapy for the treatment of hypercholesterolemia.

Structural characteristic and molecular docking simulation of fish protein-derived peptides: Recent updates on antioxidant, anti-hypertensive and anti-diabetic peptides.

Over the decade, fish protein-derived peptides (FPDP) have been evaluated for various biological activities including their mechanism of action through structure-activity relationship (SAR) and molecular simulation. SAR studies are known to provide the basic structural information of the active site which can be used for designing synthetic bioactive peptides for application in therapeutics and medicinal purposes. In light of the above discussion, this review discusses the mechanism of action and SAR of the FPDP with a focus on three widely studied bioactive properties including antioxidant, antihypertensive and anti-diabetic activities. The emphasis is given to the recently purified and identified FPDP from various seafood resources. A brief discussion has been made on their structural characteristics and mechanism of action towards antioxidant, angiotensin-I converting enzyme (ACE) inhibition, and dipeptidyl peptidase-IV (DPP-IV) inhibitory activities. Additionally, the importance and future perspective of SAR of food-derived bioactive peptides have been addressed.

A comparative analysis of anti-lipidemic potential of soybean (Glycine max) protein hydrolysates obtained from different ripening stages: Identification, and molecular interaction mechanisms of novel bioactive peptides.

This study aims to investigate the potentials of mature (MSPHs) and young (YSPHs) soybean enzymatic protein hydrolysates for the inhibition of pancreatic lipase (PL) and cholesterol esterase (C-Ease) enzymes. Higher proteins degradation levels were recorded with Bromelain compared to Flavourzyme and Alcalase, and upon hydrolysis, improved PL and C-Ease inhibition performances were displayed compared to unhydrolyzed proteins. Afterwards, six PHs with potent anti-lipidemic activities were selected for sequencing using LC-MS QTOF and molecular binding studies. Peptides FPFPRPPHQ, QCCAFEM, FAPEFLK from MSPHs and SFFFPFELPRE, FMYL, PFLL, FPLL, LPHF from YSPHs were predicted to possess potent inhibitory activities against PL. Furthermore, FPFPRPPHQ, FMYL, MMLM from MSPHs, and SFFFPFELPRE from YSPHs were predicted to be potent inhibitors of C-Ease. FPFPRPPHQ and SFFFPFELPRE derived from MSPHs and YSPHs, respectively, demonstrated effective inhibition potentialities against both PL and C-Ease. Therefore, mature and young soybean-derived protein hydrolysates could be recognized as a potential ingredient in the management of hypercholesterolemia.

Plant-derived proteins as a sustainable source of bioactive peptides: recent research updates on emerging production methods, bioactivities, and potential application.

The development of novel protein sources to compensate for the expected future shortage of traditional animal proteins due to their high carbon footprint is a major contemporary challenge in the agri-food industry currently. Therefore, both industry and consumers are placing a greater emphasis on plant proteins as a sustainable source of protein to meet the growing nutritional demand of ever increasing population. In addition to being key alternatives, many plant-based foods have biological properties that make them potentially functional or health-promoting foods, particularly physiologically active peptides and proteins accounting for most of these properties. This review discusses the importance of plant-based protein as a viable and sustainable alternative to animal proteins. The current advances in plant protein isolation and production and characterization of bioactive hydrolysates and peptides from plant proteins are described comprehensively. Furthermore, the recent research on bioactivities and bioavailability of plant protein-derived bioactive peptides is reviewed briefly. The limitations of using bioactive peptides, regulatory criteria, and the possible future applications of plant protein-derived bioactive peptides are highlighted. This review may help understand plant proteins and their bioactive peptides and provide valuable suggestions for future research and applications in the food industry.

Multifunctional bioactive properties of hydrolysates from colocynth (Citrullus colocynthis) seeds derived proteins: Characterization and biological properties.

Citrullus colocynthis (Colocynth) has gained a great deal of interest in their applications as indigenous nutraceutical and as a functional food ingredient. The intact colocynth seed protein was enzymatically hydrolyzed using proteolytic enzymes (alcalase, bromelain, and chymotrypsin) at different time intervals of 3, 6, and 9 h. The highest degree of hydrolysis (87.82%) was observed in chymotrypsin derived colocynth seed protein hydrolysates (CSPH) for 9 h. The CSPHs was further investigated through in-vitro assay to explore its potential biological activity such as antioxidant, inhibition of enzymatic marker related to diabetes (DPP-IV, α-glucosidase and α-amylase) and hyperlipidaemia (cholesteryl esterase and pancreatic lipase). Chymotrypsin hydrolysate showed the strongest DPPH (65.7 mM TEAC) and ABTS (525.2 mM TEAC) radical scavenging activity after 6 h of hydrolysis. Moreover, chymotrypsin-treated CSPH for 6 h inhibited cholesteryl esterase (IC50 = 13.68 µg/mL) and pancreatic lipase (IC50 = 14.12 µg/mL) significantly when compared to native protein. Whereas, bromelain and alcalase treated hydrolysate for 6 h effectively inhibited α-glucosidase and α-amylase at an inhibitory concentration of IC50 = 13.27 µg/mL and of IC50 = 17 µg/mL. Overall, the findings indicated that protein hydrolysates exhibited superior biological activity than intact colocynth seed proteins isolate (CSPI) and could be a sustainable source of bioactive peptides.

Nutraceutical and bioactive potential of high-quality date fruit varieties (Phoenix dactylifera L.) as a function of in-vitro simulated gastrointestinal digestion.

The present study aims to investigate the digestive process (gastric and intestinal phases) effects on the survivability of total and individual phenolic compounds, and the in vitro health-related bioactive properties of four high-quality and commonly consumed dates (Phoenix dactylifera) varieties (Safawi, Khalas, Khudri, and Booman). Phenolic compounds were analyzed by HPLC-UV (at 275 nm) and a higher amount of phenolics were identified in Khalas and Booman intestinal digested extracts, compared to the other date varieties-based extracts, which corroborates with the total phenolic contents in those samples, with respective values of 186.5 and 358.14 mg GAE/100 g. Considering their bioactive potentialities, the highest DPPH radical scavenging activities, of around 320 TEAC µg/mL, were observed with Khalas and Khudri gastric extracts. In contrast, Khalas intestinal extract displayed the highest ABTS radical scavenging potential of 969 TEAC µg/mL. Moreover, the Safawi intestinal extract, along with Khalas and Booman gastric extracts, showed the highest increase in the α-glucosidase inhibition activity, compared to the other date varieties-based extracts. Safawi and Khalas intestinal extracts displayed the highest DPP-IV inhibition activities (IC50 of 2.85 µg/mL). Additionally, regarding the pancreatic lipase and cholesterol esterase inhibition, Khudri and Khalas varieties after intestinal digestion demonstrated the highest activities. These results suggested that the Khalas variety showed more potent bioactive properties than other date varieties, mainly related to the variations in the phenolic content between date varieties. Overall, this study provides additional insight into investigating these dates varieties upon their simulated gastro-intestinal digestion and exhibition of multifunctional bioactive properties.

Lactobacillus reuteri-fortified camel milk infant formula: Effects of encapsulation, in vitro digestion, and storage conditions on probiotic cell viability and physicochemical characteristics of infant formula.

Lactobacillus reuteri fortified camel milk infant formula (CMIF) was produced. The effect of encapsulation in different matrices (sodium alginate and galacto-oligosaccharides) via spray drying, simulated infant gastrointestinal digestion (SIGID), and storage conditions (temperature and humidity) on the viability of L. reuteri in CMIF and the physicochemical properties of CMIF were evaluated. Compared with free cells, probiotic cell viability was significantly enhanced against SIGID conditions upon encapsulation. However, L. reuteri viability in CMIF decreased after 60 d of storage, predominantly at higher storage humidity and temperature levels. At the end of the storage period, significant changes in the color values were observed in all CMIF, with a reduction in their greenness, an increase in yellowness, and a wide variation in their whiteness. Moreover, pH values and caking behavior of all CMIF stored at higher temperature (40°C) and humidity [water activity (aw) = 0.52] levels were found to be significantly higher than the samples stored under other conditions. Over 30 d of storage at lower humidity conditions (aw = 0.11 and 0.33) and room temperature (25°C), no significant increase in CMIF lipid oxidation rates was noted. Fourier-transform infrared spectroscopy analysis showed that, compared with the other storage conditions, CMIF experienced fewer changes in functional groups when stored at aw = 0.11. Microscopic images showed typical morphological characteristics of milk powder, with round to spherical-shaped particles. Overall, camel milk fortified with encapsulated L. reuteri can be suggested as a promising alternative in infant formula industries, potentially able to maintain its physicochemical characteristics as well as viability of probiotic cells when stored at low humidity levels (aw = 0.11) and temperature (25°C), over 60 d of storage.

Camel whey protein with enhanced antioxidative and antimicrobial properties upon simulated gastro-intestinal digestion.

Background: Whey proteins and their peptide derivatives have attracted a great attention of researchers in the pharmaceutical and nutritional fields, due to their numerous bio-functionalities. Aim: In the present research study, enzymatic protein hydrolysates (CWPHs) from camel whey proteins (CWPs) were produced and investigated for their antioxidant and antimicrobial potentials. Methods: Herein, Pepsin (gastric), and Trypsin and Chymotrypsin (pancreatic) enzymes were used to produce CWPHs. The obtained hydrolysates were characterize to ascertain the level of protein degradation and studies on their antimicrobial and antioxidant potential were conducted. Results: Among all CWPHs, a complete degradation of all different protein bands was perceived with Chymotrypsin-derived CWPHs, whereas, light bands of serum albumin and α-lactalbumin were observed with Trypsin and Pepsin-derived CWPHs. After enzymatic degradation, both CWPHs antioxidant and antimicrobial activities were improved. Chymotrypsin-derived CWPHs demonstrated higher DPPH and ABTS radical scavenging activities, anent the increase in proteolysis time. Compared to unhydrolyzed CWPs, higher metal chelating activities were displayed by Trypsin-derived CWPHs. No significant increase in the FRAP activities was noticed after CWPs hydrolysis using Trypsin and Chymotrypsin, while Pepsin-derived CWPHs showed higher reducing power. In terms of antimicrobial activity, significantly higher bacterial growth inhibition rates were exhibited by CWPHs compared to the unhydrolyzed CWP. Conclusion: Overall, CWPHs displayed enhanced antioxidative and antimicrobial properties.

Ultrasonication as a novel processing alternative to pasteurization for camel milk: Effects on microbial load, protein profile, and bioactive properties.

Ultrasonic technology presents a promising novel tool in the food industry for the processing of milk and dairy products. In this study, we investigated the effects of ultrasonication (US) as an alternative to thermal pasteurization for stabilization of the bioactive properties of camel milk. Camel and bovine milk samples were subjected to US at 6 different power levels (US1-US6), and 1 set of each type of milk was concurrently subjected to flash heat pasteurization (FHP) for comparative analysis (100 mL; n = 4). The microbiological and bioactive parameters of the samples were analyzed during 7 d of storage at 4°C. In both milk types subjected to US ≥ 140 W (US3), the bacterial load was reduced by almost 4 log cycles and complete reduction of microbial load was achieved with US = 170 W and US = 210 W (US5 and US6 treatments, respectively). No significant changes in protein patterns were observed with either FHP or US treatment. In addition, bioactive properties (cholesteryl esterase and pancreatic lipase inhibition) were either enhanced or retained at US3 or higher. 2,2'-Azino-bis-3-ethylbenzthiazoline-6-sulfonic acid and ferric reducing antioxidant power activities in camel milk were decreased after FHP treatment but increased or retained upon US, particularly at US3 and US4 (160 W). Overall, under our experimental conditions, US4 was effective in completely reducing the microbial count, while concomitantly retaining different bioactive properties of both camel and bovine milk. These outcomes highlight the potential of US at 160 W as an efficient nonthermal alternative processing method for milk.

Camel milk-derived probiotic strains encapsulated in camel casein and gelatin complex microcapsules: Stability against thermal challenge and simulated gastrointestinal digestion conditions.

Probiotics have received increased attention due to their nutritional and health-promoting benefits. However, their viability is often impeded during food processing as well as during their gastrointestinal transit before reaching the colon. In this study, probiotic strains Lactobacillus rhamnosus MF00960, Pediococcus pentosaceus MF000967, and Lactobacillus paracasei DSM20258 were encapsulated within sodium alginate, camel casein (CC), camel skin gelatin (CSG) and CC:CSG (1:1 wt/wt) wall materials. All 3 strains in encapsulated form showed an enhanced survival rate upon simulated gastrointestinal digestion compared with free cells. Among the encapsulating matrices, probiotics embedded in CC showed higher viability and is attributed to less porous structure of CC that provided more protection to entrapped probiotics cells. Similarly, thermal tolerance at 50°C and 70°C of all 3 probiotic strains were significantly higher upon encapsulation in CC and CC:CSG. Scanning electron microscope micrographs showed probiotic strains embedded in the dense protein matrix of CC and CSG. Fourier-transform infrared spectroscopy showed that CC- and CSG-encapsulated probiotic strains exhibited the amide bands with varying intensity with no significant change in the structural conformation. Probiotic strains encapsulated in CC and CC:CSG showed higher retention of inhibitory properties against α-glucosidase, α-amylase, dipeptidyl peptidase-IV, pancreatic lipase, and cholesteryl esterase compared with free cells upon exposure to simulated gastrointestinal digestion conditions. Therefore, CC alone or in combination with CSG as wall materials provided effective protection to cells, retained their bioactive properties, which was comparable to sodium alginate as wall materials. Thus, CC and CC:CSG can be an efficient wall material for encapsulation of probiotics for food applications.

A comparative investigation into novel cholesterol esterase and pancreatic lipase inhibitory peptides from cow and camel casein hydrolysates generated upon enzymatic hydrolysis and in-vitro digestion.

Cow (CwC) and camel casein (CaC) hydrolysates were generated using Alcalase™ (CwCA and CaCA) and Pronase-E (CwCP and CaCP) each for 3 and 6 h, and investigated for their potential to inhibit key lipid digesting enzymes i.e., pancreatic lipase (PL) and cholesteryl esterase (CE). Results revealed stronger PL and CE inhibition by CaC hydrolysates compared to CwC. Potent hydrolysates (CwCP-3 h and CaCA-6 h) upon simulated gastrointestinal digestion (SGID) showed significant improvement in inhibition of both PL and CE. However, both the SGID hydrolysates showed similar extent of PL and CE inhibition and were further sequenced for peptide identification. Peptides MMML, FDML, HLPGRG from CwC and AAGF, MSNYF, FLWPEYGAL from CaC hydrolysates were predicted to be most active PL inhibitory peptides. Peptide LP found in both CwC and CaC hydrolysates was predicted as active CE inhibitor. Thus, CwC and CaC could be potential source of peptides with promising CE and PL inhibitory properties.