Breast-Milk Amylase Activity in English and Gambian Mothers: Effects of Prolonged Lactation, Maternal Parity, and Individual Variations

Abstract

SUBJECTS AN D METHODSevaluate the potenti al role of breast-milk amylase in digestion of food carbo hydrate given in complement of breast-feedin g.The object of our study was to measure breast-milk am ylase activity in two different groups of women practicing prolonged lactati on: mothers living in an affiuent city of England, and less privileged mothers living in a rural village of Th e Gambia, West Africa, whose children are at a high risk for malnutrition . Th e results demonstrated that am ylase is secreted into breast milk th rou ghout 2 y of lactation in quantities of potentially valuable digestive capacity and that the activity of this enzyme is rema rkably similar in the breast milk of English and Gambian women. T he results brought out the great differences in breast-milk amylase activity amo ng mothers living in the same community.Within-subj ect variations. Before the main studies, a detailed investigation of within-subject variations in amylase activity was cond ucted on English and Gambian subjects, to develop a sampling protoco\' Within-feed and diurn al variations, and consistency within indi viduals were examined in five English and five Gambian mothers. The English mothers provided a small sample of milk from both breasts by manual expression, just before and after each feed duri ng a single 24 h period. Th e mothers were 27-to 32-y-old, parity 1-3, and were at vario us stages oflactatio n ranging from 4 to 13 wk of lactation . Th e feed frequency per day was 6-7. The Ga mbian moth ers provided a small sample of mil k from both breasts by ma nual expression at 0800 , 1200, 1500, 1800, and 2100 h on 3 con secuti ve days. The moth ers were 27-to 33-y-old, parity 6-8, an d were at 5-6 wk of lactati on . In addition , to stud y within-subject variations du ring exclusive breast-feedi ng, a longitudinal stud y was conducted in a group of seven mot hers who were recru ited in the lactation clinic of the Helena Venizelos Maternity Hospital, Athens, Gree ce, where it is clinic policy to recommend exclusive breast-feeding for 6 mo. The mot hers were 20-to 37-y-old, parity 1-4, and were exclusively breast-feeding throughout the study . The moth ers provided small sam ples of transiti onal milk (3-1 1 d postpartum) and sequential sampl es of mature milk at approxima tely monthl y inte rvals for 6 mo from both breasts.Milk collection. On the strength of the results of these studies (detailed later) a sim ple samp ling procedu re was adopted for the further studies: amylase was measured in a small sample « 1 mL) of milk obta ined from both breasts on one occasion, irrespective of the suckling pattern, and milk samp les from left and right breast were pooled before analysis.Stu dy comm unities. Breast-milk am ylase was measured in two cross-sectional groups of English and Gambian mothe rs. Th e English subjects lived in the Cambridge area and were recruited th rough local lactation support groups. Fifty-eight mothers par-502 ABSTRACT. Breast milk contains an amyla se that may contribute to carboh ydrate diges...

Protein-Linked Glycan Degradation in Infants Fed Human Milk

“…Four glycosidases are present in intact human milk. Amylase does not degrade any of the human milk PLG structures identified to date [49]. The regiospecificities of the other three glycosidases in human milk-α-L-fucosidase [50], N -acetyl-β-D-hexosaminidase [51,52], and sialidase [53]-remain undetermined, so whether they can act on human milk PLGs is unknown.…”

“…α-Amylase (EC 3.2.1.1), which cleaves terminal α-1,4 linked Glc from starch, is present in milk of term mothers as early as the first week postpartum [49]. Milk α-amylase activity in English and Gambian mothers between 0.5 and 27 months of lactation range from .08 to 3.53 IU/mL [49].…”

“…Milk α-amylase activity in English and Gambian mothers between 0.5 and 27 months of lactation range from .08 to 3.53 IU/mL [49]. However, there are no reports of α-1,4 linked Glc on human milk PLG.…”

Nutritive and Bioactive Proteins in Breastmilk

“…Colostrum is known to contain higher activities compared to transition or mature milk [82] . There is a further decrease of approximately 35% of the activity beyond the first trimester of breastfeeding [83] . Additionally, higher parity may also reduce amylase activity by half [83] .…”

“…There is a further decrease of approximately 35% of the activity beyond the first trimester of breastfeeding [83] . Additionally, higher parity may also reduce amylase activity by half [83] . Preterm milk contains equal amounts of amylase activity as term milk [84] .…”