Abstract
The aim of this study was to compare the digestion of milk proteins from different species using an in vitro gastrointestinal model. Raw and heated milks from bovine, caprine, human and equine species were digested by human digestive enzymes. Digestion was performed in two 30-min sequential steps by digestive juices from the stomach (pH 2.5/37 °C) and from the duodenum (pH 8.0/37 °C). The degradation patterns of the milk proteins were visualized by SDS-PAGE and quantified using the ImageQuant program. Caseins in the equine milk were rapidly digested by the gastric juice in contrast to the caseins from the other species. During the subsequent digestion by the duodenal juice most of the caseins from all species were degraded within 5 min, and within 30 min only traces of caseins were detected. The mean casein micellar size varied between species in the range of 146.0–311.5 nm (equine > caprine > bovine > human). The α-lactalbumin from all species appeared to be very resistant to both gastric and duodenal digestions. A similar trend was shown for β-lactoglobulin from bovine and caprine milks, of which ∼ 60% intact protein remained, while only 25% remained intact in equine milk after total digestion. Equine milk contained a high amount of lysozyme, of which 60% remained intact in the present study. In heated milks from all species, only α-lactalbumin degradation increased approximately 12–20% in comparison to the raw milk. This study shows that equine milk with fast digestible proteins could be considered as a replacement for bovine milk in the diet of people with special needs, such as infants and the elderly.
Abstract
(pH 2.5/37 °C) (pH 8.0/37 °C) 30 min SDS-PAGE 5 min 30 min 146.0 ∼ 311.5 nm, α-β- 60% 25% 60% α- 12 ∼ 20%
Résumé
Le but de cette étude était de comparer la digestion des protéines laitières provenant de différentes espèces en utilisant un modèle gastro-intestinal in vitro. Des laits crus et traités thermiquement des espèces bovines, caprines, équines et humaines ont été digérés par des enzymes digestives humaines. La digestion a été réalisée au cours de deux étapes séquentielles de 30 min par des sucs digestifs gastriques (pH 2,5/37 °C) et duodénaux (pH 8,0/37 °C). Les profils de dégradation des protéines laitières ont été visualisés par SDS-PAGE et quantifiés à l’aide du programme ImageQuant. Les caséines du lait équin étaient rapidement digérées par le suc gastrique contrairement aux caséines des autres espèces. Au cours de la digestion suivante par le suc duodénal, la plupart des caséines de toutes les espèces étaient dégradées en 5 min, et après 30 min seules des traces des caséines étaient détectées. La taille moyenne des micelles de caséines variait de 146,0 à 311,5 nm selon les espèces (équin > caprin > bovin > humain). L’α-lactalbumine de toutes les espèces apparaissait être très résistante à la fois à la digestion gastrique et duodénale. Une tendance similaire était observée pour la β-lactoglobuline du lait bovin et caprin dont 60 % des protéines restaient intactes, contre seulement 25 % pour le lait équin après digestion totale. Le lait équin contenait une grande quantité de lysozyme dont 60 % demeurait intact dans cette étude. Dans les laits traités thermiquement de toutes les espèces, seule la dégradation de l’α-lactalbumine augmentait de 12 à 20 % environ par rapport au lait cru. Cette étude montre que les laits équins avec leurs protéines rapidement digestibles pourraient être pris en compte comme substitut du lait bovin dans l’alimentation de populations avec des besoins spécifiques, comme les très jeunes enfants et les personnes âgées.
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Abbreviations
- α-la:
-
α-Lactalbumin
- β-lg:
-
β-Lactoglobulin
- CNs:
-
caseins
- GA:
-
glutaraldehyde
- GMP:
-
glycomacropeptide
- HDJ:
-
human duodenal juice
- HGJ:
-
human gastric juice
- IgHc:
-
immunoglobulin heavy chain
- LF:
-
lactoferrin
- LZ:
-
lysozyme
- SA:
-
serum albumin
- SDS-PAGE:
-
sodium dodecyl sulfate-polyacrylamide gel electrophoresis
- SMUF:
-
simulated milk ultrafiltrate
References
Almaas H., Berner V., Holm H., Langsrud T., Vegarud G.E., Degradation of whey from caprine milk by human proteolytic enzymes, and the resulting antibacterial effect against Listeria monocytogenes, Small Rum. Res. 79 (2008) 11–15.
Almaas H., Cases A.-L., Devold T.G., Holm H., Langsrud T., Aabakken L., Ådnøy T., Vegarud G.E., In vitro digestion of bovine and caprine milk by human gastric and duodenal enzymes, Int. Dairy J. 16 (2006) 961–968.
Almaas H., Holm H., Langsrud T., Flengsrud R., Vegarud G.E., In vitro studies of the digestion of caprine whey proteins by human gastric and duodenal juice and the effects on selected microorganisms, Br. J. Nutr. 96 (2006) 562–569.
Bos C., Mahé S., Gaudichon C., Benamouzig R., Gausserès N., Luengo C., Ferrière F., Rautureau J., Tomé D., Assessment of net postprandial protein utilization of N-15-labelled milk nitrogen in human subjects, Br. J. Nutr. 81 (1999) 221–226.
Dalgleish D.G., Spagnuolo P.A., Douglas Goff H., A possible structure of the casein micelle based on high-resolution field-emission scanning electron microscopy, Int. Dairy J. 14 (2004) 1025–1031.
Dangin M., Boirie Y., Guillet C., Beaufrère B., Influence of the protein digestion rate on protein turnover in young and elderly subjects, J. Nutr. 132 (2002) 3228S-3233S.
Dangin M., Guillet C., Garcia-Rodenas C., Gachon P., Bouteloup-Demange C., Reiffers-Magnani K., Fauquant J., Ballèvre O., Beaufrère B., The rate of protein digestion affects protein gain differently during aging in humans, J. Physiol. 549 (2003) 635–644.
de Kruif C.G., Holt C., Casein micelle structure, function and interactions, in: Fox P.F., McSweeney P.L.H. (Eds.), Advanced Dairy Chemistry, Vol. 1: Proteins, Kluwer Academic/Plenum Publishers, New York, USA, 2003, pp. 233–276.
Eriksen E.K., Vegarud G.E., Langsrud T., Almaas H., Lea T., Effect of milk proteins and their hydrolysates on in vitro immune responses, Small Rum. Res. 79 (2008) 29–37.
Exposito I.L., Recio I., Antibacterial activity of peptides and folding variants from milk proteins, Int. Dairy J. 16 (2006) 1294–1305.
Fox P.F., McSweeney P.L.H., Dairy Chemistry and Biochemistry, Blackie Academic and Professional, London, UK, 1998.
Holm H., Hanssen L.E., Krogdahl A., Florholmen J., High and low inhibitor soybean meals affect human duodenal proteinase activity differently — in vivo comparison with bovine serum-albumin, J. Nutr. 118 (1988) 515–520.
Jenness R., Koops J., Preparation and properties of a salt solution which simulates milk ultrafiltrate, Neth. Milk Dairy J. 16 (1962) 153–164.
Kim S.B., Ki K.S., Khan M.A., Lee W.S., Lee H.J., Ahn B.S., Kim H.S., Peptic and tryptic hydrolysis of native and heated whey protein to reduce its antigenicity, J. Dairy Sci. 90 (2007) 4043–4050.
Korhonen H., Pihlanto A., Bioactive peptides: production and functionality, Int. Dairy J. 16 (2006) 945–960.
Krogdahl A., Holm H., Inhibition of human and rat pancreatic proteinases by crude and purified soybean proteinase-inhibitors, J. Nutr. 109 (1979) 551–558.
Lacroix M., Bos C., Léonil J., Airinei G., Luengo C., Dare S., Benamouzig R., Fouillet H., Fauquant J., Tomé D., Gaudichon C., Compared with casein or total milk protein, digestion of milk soluble proteins is too rapid to sustain the anabolic postprandial amino acid requirement, Am. J. Clin. Nutr. 84 (2006) 1070–1079.
Laemmli U.K., Cleavage of structural proteins during assembly of head of bacterio-phage-T4, Nature 227 (1970) 680–685.
Mahé S., Benamouzig R., Gaudichon C., Huneau J.F., Decruz I., Rautureau J., Tomé D., Nitrogen movements in the upper jejunum lumen in humans fed low amounts of casein or beta-lactoglobulin, Gastroenterol. Clin. Biol. 19 (1995) 20–26.
Mahé S., Roos N., Benamouzig R., Davin L., Luengo C., Gagnon L., Gausserges N., Rautureau J., Tomé D., Gastrojejunal kinetics and the digestion of [N-15]beta-lactoglobulin and casein in humans: the influence of the nature and quantity of the protein, Am. J. Clin. Nutr. 63 (1996) 546–552.
Malacarne M., Martuzzi F., Summer A., Mariani P., Protein and fat composition of mare’s milk: some nutritional remarks with reference to human and cow’s milk, Int. Dairy J. 12 (2002) 869–877.
Martin P., Grosclaude F., Improvement of milk protein-quality by gene technology, Livest. Prod. Sci. 35 (1993) 95–115.
McMahon D.J., Oommen B.S., Supramolecular structure of the casein micelle, J. Dairy Sci. 91 (2008) 1709–1721.
Miranda G., Mahé M.-F., Leroux C., Martin P., Proteomic tools to characterize the protein fraction of Equidae milk, Proteomics 4 (2004) 2496–2510.
Ochirkhuyag B., Chobert J.M., Dalgalarrondo M., Haertlé T., Characterization of mare caseins. Identification of αs1- and αs2-caseins, Lait 80 (2000) 223–235.
Orsi N., The antimicrobial activity of lactoferrin: current status and perspectives, Biometals 17 (2004) 189–196.
Park Y.W., Goat milk — chemistry and nutrition, in: Park Y.W., Haenlein G.F.W. (Eds.), Handbook of Milk of Non-Bovine Mammals, Blackwell Publishing, Oxford, UK, 2006, pp. 34–58.
Salami M., Yousefi R., Ehsani M.R., Dalgalarrondo M., Chobert J.-M., Haertlé T., Razavi S.H., Saboury A.A., Niasari-Naslaji A., Moosavi-Movahedi A.A., Kinetic characterization of hydrolysis of camel and bovine milk proteins by pancreatic enzymes, Int. Dairy J. 18 (2008) 1097–1102.
Sanchez-Chiang L., Cisternas E., Ponce O., Partial-purification of pepsins from adult and juvenile salmon fish Oncorhynchus keta. Effect of NaCl on proteolytic activities, Comp. Biochem. Physiol. B 87 (1987) 793–797.
Tomé D., Debabbi H., Physiological effects of milk protein components, Int. Dairy J. 8 (1998) 383–392.
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Inglingstad, R.A., Devold, T.G., Eriksen, E.K. et al. Comparison of the digestion of caseins and whey proteins in equine, bovine, caprine and human milks by human gastrointestinal enzymes. Dairy Sci. Technol. 90, 549–563 (2010). https://doi.org/10.1051/dst/2010018
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DOI: https://doi.org/10.1051/dst/2010018