Gy. Wiederschain et Ds. Newburg, HUMAN-MILK FUCOSYL-TRANSFERASE AND ALPHA-L-FUCOSIDASE ACTIVITIES CHANGE DURING THE COURSE OF LACTATION, Journal of nutritional biochemistry, 6(11), 1995, pp. 582-587
Human milk is rich in fucosylated oligosaccharides and other glycoconj
ugates, some of which affect interactions between pathogens and host c
ell surface. Two types of enzymes, fucosyltransferase and alpha-L-fuco
sidase, involved in the biosynthesis and degradation of these compound
s, were analyzed in random samples of human milk from healthy donors.
In mature milk (days 52 to 78), the individual variability for fucosyl
transferase was twice that of fucosidase. The activities of both enzym
es were observed to change over the course of lactation from day 3 to
day 370. alpha-Fucosyltransferase activity was greatest during the fir
st 30 days of lactation and declined significantly between 30 and 100
days. From day 100, fucosyltransferase activity remained nearly consta
nt. Fucosidase activity was high at the onset of lactation followed by
a precipitous decline, reaching a nadir by the second week. After the
fourth week, the alpha-L-fucosidase activity increased in direct prop
ortion to the length of lactation. The possible relationship of these
enzymes to the fucosyloligosaccharide content of human milk are discus
sed.