Abstract:
Oligosaccharides have been found effective in gastrointestinal normal flora proliferation and pathogen suppression, dental caries prevention, enhancement of immunity, facilitation of mineral absorption, source of antioxidant, antibiotic alternative, regulators of blood glucose in diabetics and serum lipids in hyperlipidemics. The enormous biological activities of oligosaccharides such as immunostimulant, anti-tumour, anti-cancer, anti-inflammatory, anti-complementary, anti-viral, anti-microbial, anti-oxidant, hypoglycemic activity, lipid lowering and regulation of mineral absorption are well reported. In our endeavor to find biologically active novel oligosaccharides, donkey milk was taken, which is a rich source of oligosaccharides and its milk is used as anti-hypertensive, anti-oxidative and heart strengthening agent in folk medicine. For this purpose donkey milk was processed by modified method of Kobata and Ginsburg followed by Gel filtration HPLC and Column Chromatography (CC) which resulted in the isolation of one novel milk oligosaccharide namely Quinose. The structure of purified milk oligosaccharide was determined with the help of chemical degradation, chemical transformation, spectroscopic techniques like 1D-NMR (¹H and ¹³C), 2D-NMR (COSY, TOCSY, HSQC and HMBC), Structure Reporter Group (SRG) theory and Mass spectrometry (ESI-MS). The geometry optimization of compound was done by using B3LYP method at 6-31G (d, p) basis set employing Density Functional Theory (DFT).  The structure is elucidated in Fig. 4.

Keywords: Donkey Milk, Oligosaccharides, Quinose.