Carnitine Concentrations in the Milk of Different Species and Infant Formulas

Abstract

Carnitine concentrations were measured in the milk of sheep, cows, goats, and horses, in human milk of term and preterm infants and in European infant formulas. There were significant species’ differences in carnitine milk content. Acylcarnitme concentrations ranged from 13 to 47% of total carnitine. This may be related to differences in maternal and/or mammary gland metabolism. The concentration of long-chain acylcarnitine in milk was under 1 % in all investigated species. In cow’s milk, there was a decrease in acylcarnitine concentration during the first 2 months of lactation. In human milk, carnitine concentrations did not change during the 1 st month postpartum, but maternal plasma carnitine concentrations increased and plasma concentrations of acylcarnitine were always lower than those in simultaneously sampled milk. Milk carnitine concentrations in mothers of premature infants were not different from those in mothers of term infants. European formulas based on cow’s milk contained somewhat more carnitine than human milk. However, very low carnitine concentrations were found in soy-based or protein hydrolysate formulas. This may lead to nutritional carnitine deficiency in infants receiving these formulas without carnitine supplementation.

Scientific Opinion on the essential composition of infant and follow-on formulae

“…In studies investigating L-carnitine concentrations in milk from different species, mean total carnitine concentrations have been reported to be in the range 0.9-1.6 mg/100 kcal in human milk (Sandor et al, 1982;Penn et al, 1987;Ferreira, 2003), 4.1-6.7 mg/100 kcal in cow's milk (Sandor et al, 1982;Penn et al, 1987;Ferreira, 2003) and 3.2-4.4 mg/100 kcal in goat's milk (Sandor et al, 1982;Penn et al, 1987 Human milk contains free nucleosides, free nucleotides, RNA and DNA. The concentrations of "total potentially available nucleotides", defined by some authors as the sum of free nucleosides, free nucleotides, nucleotide-containing adducts (such as NAD and uridine diphosphate (UDP) glucose) and nucleotide polymers, were reported to be around 10.5-11.0 mg/100 kcal in milk from Asian, American and European mothers.…”

Total, Free, Short-Chain and Long-Chain Acyl Carnitine Levels in Arabian Camel Milk <i>(Camelus dromedarius)</i>

“…Mammary excretion of L-CA was also found to be independent of dietary L-CA intake, partly because of the body's abil ity to synthesize it from lysine and methio nine, and also because of mobilization of its stores from high storage tissues such as skele tal muscle [3], On the other hand, among the camel tissues, skeletal muscle possessed the highest amount of L-CA while the lowest amount was found in kidney which may be reflected by differences in milk levels in those species investigated [7], However, it has been studied that labelled L-CA injected into lad ing rats is rapidly secreted by the mammary gland [12], Significant variations in L-CA were also observed in the camel liver and kid ney compared to other species [7], These find ings may suggest that L-CA levels in plasma, tissues and milk are regulated by different mechanisms. The pronounced discrepancies in L-CA milk concentrations among animal species is well known [4] but the reasons are obscure.…”

“…The daily requirement of the body for L-CA has been reported to range from 2 to 100 mg (10-620 |imol), reaching 300 mg (1,850 pmol) in some cases [3], Data for L-CA levels in milk are available for most laboratory and domestic animals, humans and infant formulas [4], while its lev els in the Arabian or one-humped camel (Camelus dromedarius) milk have not been re ported. The Arabian camel is a unique animal in that it is exposed to the harsh climate of the desert and hence is constantly exposed to stress conditions.…”

Goat milk consumption protects DNA against damage induced by chronic iron overload in anaemic rats

“…However discrepancies exist between different feeding studies, on the effect of high dietary Fe concentrations, and the protective effects of antioxidants which might be dependent of the type and quality of fat in the diets (Brandsch, Ringseis, & Eder, 2002). We reported previously that goat milk fat is of higher nutritional quality than cow milk since it is richer in medium chain triglycerides (MCT) (Alférez et al, 2001) and has higher carnitine content (Penn, Dolderer, & Schmidt-Sommerfeld, 1987). These lipids increase the energy production derived from fatty acids (Fushiki, Matsumoto, Inoue, Kawada, & Sugimoto, 1995;Van Zyl, Lambert, Hawley, Noakes, & Dennis, 1996), thereby limiting the availability of substrates for lipid peroxidation when consuming goat milk.…”