Abstract:

In order to maximize the extraction yield of polysaccharides from the seeds of adlay (Coix lachryma-jobi L. var. mayuen Stapf), an orthogonal array design L9(33) was applied to optimize the extraction conditions including raw material/ water as well as extraction temperature and duration, of which the effects on polysaccharide extraction yield were initially dealt with by single factor method. Finally, the extracted polysaccharides were purified on Sephadex G-75 gel column, and the chromatographic characteristics were investigated and purity identification was carried out. Material/water ratio of 1:15 (g/mL), extraction temperature of 100 ℃ and extraction time of 150 min were found optimal, and the extraction yield of polysaccharides was 5.53% under these optimal extraction conditions. The purified polysaccharides were analyzed by UV spectroscopy to contain neither protein nor nucleic acids.

Key words: coixan, orthogonal array design, extraction, isolation and purification