磷对霍山石斛类原球茎悬浮培养细胞生长和多糖合成的影响

Effect of Phosphate on Growth and Polysaccharide Production by Suspension Cultures of Protocorm-like Bodies of Dendrobium huoshanense

在确定了最适接种量和外植体细胞生理时间的基础上,研究了在不同起始磷浓度下,霍山石斛类原球茎生长、碳、氮消耗和多糖积累的动力学特性。以生长30d的类原球茎为材料,在接种量为100g/L时,类原球茎生长的最佳起始磷浓度为2.5mmol/L,培养36d时,类原球茎鲜重达496.5g/L。动力学分析表明,磷是霍山石斛类原球茎生长的限制性因素,胞内磷的积累水平与细胞生长具有相关性,2.5mmol/L的磷酸盐有利于碳、氮等营养物质的吸收;而多糖积累的最佳起始磷浓度为0.312mmol/L,培养36d时,其产量为2.22g/L。

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 100g/L cells. The results indicate that the optimal concentration of phosphate in medium for cell growth of protocorm-like bodies of Dendrobium huoshanense was 2.5mmol/L and biomass was 496.5g/L （fresh weight）. Phosphate was a limited factor for cell growth and there was relationship between the levels of intracellular phosphate and cell growth. 2.5mmol/L of medium phosphate was beneficial to the absorption of carbohydrate and nitrate source. 0.312mmol/L of medium phosphate was better for accumulation of polysaccharides and production of polysaccharides was 2.22 g/L at 36 d.