[Lipoprotein lipase activity in human milk; inhibition in vitro of the glucuro-conjugation of bilirubin (author's transl)].

The lipolytic activities of esterase, lipase and lipoprotein lipase were measured in 17 samples of human milk. Lipase and esterase activities were the same in all samples. However, lipoprotein lipase activity was increased only in samples provided from mothers whose infants had prolonged neonatal jaundice; after storage these samples inhibited the glucuro-conjugation of bilirubin in vitro and their concentration in non-esterified fatty acids was high. The mechanism of action of this enzyme is discussed in relation to the physico-chemical state of fat globules.