[Effect of phosphate on growth and polysaccharide production by suspension cultures of protocorm-like bodies of Dendrobium huoshanense].

The effect of inorganic phosphate on cell growth, accumulation of polysaccharides together with nutrient utilization was investigated in suspension cultures of protocorm-like bodies of Dendrobium huoshanense. Thirty-day-old cells were transferred into liquid medium with the inoculum density of 100 g/L cells. The results indicate that the optimal concentration of phosphate in medium for cell growth of protocorm-like bodies of Dendrobium huoshanense was 2.5 mmol/L and biomass was 496.5 g/L (fresh weight). Phosphate was a limited factor for cell growth and there was relationship between the levels of intracellular phosphate and cell growth. 2.5 mmol/L of medium phosphate was beneficial to the absorption of carbohydrate and nitrate source. 0.312 mmol/L of medium phosphate was better for accumulation of polysaccharides and production of polysaccharides was 2.22 g/L at 36 d.