[01] Avidime Ohunene Makoju, Department of Human Physiology, Kaduna State Universty, Kaduna, Nigeria. [02] Olorunshola Kolawole Victor, Department of Human Physiology, University of Abuja, Abuja, Nigeria. [03] Goji Anthony Donatus Teru, Department of Human Physiology, Kaduna State Universty, Kaduna, Nigeria.

Background: Breast milk is the best nutrient source for infants. It contains all elements needed for a normal growth and development of infants. Human milk contains a large amount of sialic acid compared with bovine milk. Sialic acid contained in oligosaccharides, glycolipids and glycoproteins in milk is considered to play important roles in physiological functions in infancy. Objective: Sialic acid (N-acetylneuraminic acid, NANA) is an essential component of mucins, glycoproteins and gangliosides and therefore important for the function of cell membranes, membrane receptors and the normal development of the brain. The aim of this study is to measure and compare the concentration of sialic acid in breast milk and some selected infant formulae in Zaria, Nigeria. Method: In the present study comparison was made between the concentration of free and bound sialic acid in milk from lactating mothers at the different stages of lactation and in a range of infant formulae using Thiobarbituric Acid Assay method. A total of 67 samples of human breast milk was obtained (18 colostrum, 19 transitional, 18 mature and 12 (involutional) and five different commercial infant formulas. Result: Bound sialic acid was highest in colostrum (8.33 ± 1.77mg/ml) and more than 9% higher than in infant formulas (P value < 0.05) and this concentration decreased gradually from colostrum to the involutional stage of lactation. There was a similar pattern for free sialic acid content. Conclusion: It was concluded that human breast milk is a rich source of bound sialic acid, which contrasts to the relatively small amounts found in infant formula food. This may contribute to a normal development of brain functions.

Breastmilk, Lactation. Sialic Acid, Infant Formula

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