title: Contribution of sulfate and sulfoesters to total sulfur intake in infants fed human milk.
abstract: Colostrum (d 2-4) and mature human milk samples (d 23-30) collected from eight mothers giving birth at 31 +/- 7 wk of gestation were analyzed for total sulfur, free inorganic sulfate and acid labile sulfoesters. The data presented are representative of complete 24-h expressions. Total sulfur was measured using a wet digestion procedure in which all forms of sulfur were converted to inorganic sulfate. The sulfate was quantified by a radiometric barium precipitation assay. Total sulfur showed no marked diurnal variation, but the mean concentration in 19 colostrum samples (10.2 +/- 4.2 mmol/L) was significantly higher than in 14 mature milk samples (4.3 +/- 0.8 mmol/L) (P less than 0.001). The range of predicted 24-h intakes of sulfur by infants fed colostrum (0.78-3.22 mmol/kg body weight) was slightly higher than those fed mature milk (0.54-1.06 mmol/kg), but it was not significantly different. The combined fractions of free inorganic sulfate and acid-labile sulfoester fractions contribute less than 5% to the total sulfur content of either colostrum or mature milk. However, the physiological significance of these milk components remains to be determined.
authors.affiliation: Department of Pediatrics, Dalhousie University, Halifax, NS, Canada.
authors.forename: M E
authors.initials: ME
authors.lastname: McNally
authors.forename: S A
authors.initials: SA
authors.lastname: Atkinson
authors.forename: D E
authors.initials: DE
authors.lastname: Cole
mesh_terms: D003126:Colostrum / Q000737:chemistry*; D004952:Esters / Q000008:administration & dosage / Q000032:analysis*; D005260:Female; D006801:Humans; D007227:Infant Nutritional Physiological Phenomena; D007231:Infant, Newborn; D008895:Milk, Human / Q000737:chemistry*; D011188:Potassium / Q000032:analysis; D012016:Reference Values; D012964:Sodium / Q000032:analysis; D013431:Sulfates / Q000008:administration & dosage / Q000032:analysis*; D013455:Sulfur / Q000008:administration & dosage / Q000032:analysis*
chemical_list: D004952:Esters; D013431:Sulfates; D013455:Sulfur; D012964:Sodium; D011188:Potassium