Variation in ganglioside content of bovine dairy products.

Abstract Different protocols tested for crude extraction of gangliosides from assorted bovine dairy products gave highly variable results. The ranges, reported in nmol sialic acid/g dry wt., were 250–719 for sweet buttermilk and 165–464 for cultured buttermilk. Ganglioside content was based on sialic acid concentration determined by resorcinol/HCl assay. A modified procedure was developed to extract contaminant-free, highly purified gangliosides from these dairy products for quantitative and qualitative comparison studies. Sweet buttermilk, yogurt and cultured buttermilk were enriched in ganglioside content 10.1-, 8.4- and 6.0-fold, respectively, when compared with whole-milk levels. Skim milk had only 11.2% of the gangliosides found in whole milk. Gangliosides have been shown to exhibit antimicrobial, antiviral and enterotoxin-inhibiting properties. Cultured and concentrated dairy foods were shown to be a rich source of gangliosides and may have a potential protective effect against some pathogens.