A chemical study of the blood group-specific substances found in meconium.

Meconium (I), the characteristic first stool of the infant, is a viscid, sticky, odorless, greenish brown to black material, which is regularly seen during the 5th month of fetal development. The amount excreted after birth varies from 60 to 200 gm. It is generally considered to be an accumulation of debris consisting of desquamated cells of the alimentary tract and skin, lanugo, fatty material from the vernix caseosa, amniotic fluid, and various intestinal secretions. It has been shown to contain very large amounts of blood group-specific materials which correspond with the blood type of the individual infant and its ability to secrete blood group materials in its body fluids (2). Most previous studies of blood group-specific substances have been made on those of animal origin, because there are so few sources of the human substances in a concentration sufficient to allow separation and purification. In meconium the specific substances are present in large amounts and in a relatively pure form. Meconium has not been studied by modern chemical methods. Preliminary studies (2) indicated that meconium is for the most part soluble in water and contains little ash and large amounts of hydrolyzable, nonfermentable carbohydrate. The experimental work described in this article was undertaken to elucidate the composition of normal meconium further. It was also of interest to investigate the chemical composition of some of the individual group-specific substances in meconium, to determine whether there were any gross differences between the different types of specific substances and to see whether the substances were comparable in composition to the materials prepared by other workers. The composition of single samples of meconium from a calf’ and a dog was also studied.