Abstract • 16c

Fucosylated oligosaccharides are a major component of human milk and can inhibit enteric pathogens, but they are essentially absent from bovine milk which is the basis of infant formulas. We investigated whether milks from other species contain homologous oligosaccharides with potential to confer protection from disease in their own offspring, and with the potential to protect human infants. Oligosaccharide patterns were compared from the milks of a diverse variety of mammals, including several species of apes, monkeys, and lemurs, non-primate species such as bear, rhinoceros and giraffe, and marine mammals, seal, manatee, and dolphin. Oligosaccharides were extracted, and the neutral fraction was perbenzoylated, resolved by HPLC, and detected at 229 nm. Structures were determined by mass spectrometry. Most of the milks contained lactose, but levels were diminishingly low in bear and kangaroo. Oligosaccharides in milks of other primates resembled those of human milk, but were present at much lower concentrations, and these milks lacked most of the larger oligosaccharides found in human milk. Milks of primates more closely related to humans, e.g., apes, did not resemble human milk more closely than those of more distantly related lemurs. Some primates exhibited changes over the course of lactation reminiscent of those observed for humans, suggesting that, if these oligosaccharides should also have the capacity to inhibit pathogens, the protective capacity of their milk could also change over lactation. The milks of black and grizzly bears contained a high concentration of oligosaccharides with large numbers of unique fucosylated structures not observed in human milk; such structures could participate in protecting their extremely altricial young from pathogens. Similarly, the kangaroo milk sample, representing marsupials, also contain a large complement of complex oligosaccharides. Marine mammals generally few oligosaccharides, except for the South American fur seal, but most of the marine milks did contain significant amounts of 2-fucosyllactose. These data suggest that the patterns of oligosaccharides in milks relate less to strict phylogeny than to the reproductive strategies of each species.

Supported by HD 13021 Shriver Center for Mental Retardation, Waltham, MA, National Zoological Park, Smithsonian Institution, Washington, DC, Boston University Medical Center, Boston, MA and Department of Anthropology, University of Kansas, Lawrence, KS