Effect of several medium factors on polysaccharide and alkaloid accumulation in protocorm-like bodies of Dendrobium candidum during bioreactor culture

摘要

Polysaccharides and alkaloids are the most important bioactive compounds found in Dendrobium candidum. For mass production of polysaccharide and alkaloids from protocorm-like bodies (PLBs), this study optimized medium condition by investigating several factors affecting D. candidum PLB biomass and bioactive compound accumulation in bioreactors. During PLB bioreactor culture, sucrose is a suitable carbon source at an optimal concentration of 30 g l(-1) for polysaccharide and alkaloid production. High production of polysaccharides and alkaloids was determined in salt strengths of 1/2x, 3/4x, and full strength of the MS medium. Phosphate and ammoniumitrate ratio in normal half-strength MS medium had to be adjusted, and 1.8 mmol phosphate and 30 mmol of NO3- as the sole nitrogen source were suitable. Production of bioactive compounds by PLB bioreactor culture is a feasible and efficient method, and polysaccharide and alkaloid yields can be improved by modifying the culture medium.