ISOLATION, PURIFICATION, NMR AND MASS SPECTRAL STUDIES OF TWO NOVEL GOAT MILK OLIGOSACCHARIDES

Milk is a dynamic biological fluid that serves as the gold standard for the nutrition of newborn infants. In addition to its regular constituents, milk contains oligosaccharides; one of the most biologically diverse and significant classes of carbohydrates in living systems. These milk oligosaccharides (MOs) are complex carbohydrates that play crucial roles in numerous molecular processes affecting eukaryotic biology and patho-physiology. They exhibit a wide range of biological activities, including immune-stimulant, hypoglycemic, anti-tumor, antiviral, anticancer, anticoagulant, anti-complementary, immune-modulatory and anti-inflammatory properties. Goat milk, in particular, is a rich source of oligosaccharides with remarkable biological functions such as antibacterial, immunological, anti-inflammatory, hypoallergenic, and therapeutic effects. In traditional medicine, goat milk has been used as a remedy for tuberculosis and is also reported to enhance platelet counts during dengue fever. Given these potential health benefits, goat milk was collected and processed using a modified method of Kobata and Ginsburg. The milk underwent deproteinization, centrifugation, and lyophilization. Subsequently, the oligosaccharides were isolated via gel filtration chromatography and their homogeneity was confirmed by High-Performance Liquid Chromatography (HPLC). The oligosaccharide mixture was then acetylated and further purified using column chromatography. Finally, the acetyl groups were removed to yield oligosaccharides in their native form. The structures of isolated oligosaccharides were elucidated through a combination of chemical transformations, controlled chemical degradation, and comprehensive spectroscopic techniques, including one-dimensional (1H and 13C) and two-dimensional NMR spectroscopy (COSY, TOCSY, HSQC and HMBC), as well as mass spectrometry.