稀土元素对水母雪莲细胞生长及黄酮类化合物合成的影响

研究了稀土元素钕(Nd3+)、铈(Ce3+)、镧(La3+)和混合稀土(MRE)对摇瓶液体培养的水母雪莲细胞生长及黄酮类化合物合成的影响. 发现Ce3+和La3+及混合稀土可促进雪莲细胞的生长及黄酮类化合物的合成，其中以Ce3+效果最佳. 当初始浓度为0.025 mmol/L的Ce3+添加到改良的MS培养基中时，细胞生物量和黄酮类化合物产量最高，分别可达17.7 g/L及942 mg/L，分别是不添加稀土元素的对照实验的134.4%和166.7%；同时发现在培养基中不含外源激素6-BA的条件下，合适浓度的Ce3+可替代6-BA对雪莲细胞生长及黄酮类化合物合成的促进作用，而在培养基中不含NAA时，Ce3+不能替代NAA对雪莲细胞生长及黄酮类化合物合成的促进作用.

Promotion of Cell Growth and Flavonoids Production in Saussurea medusa Cell Suspension Cultures by Rare Earth Elements

Cell suspension culture of Saussurea medusa was cultivated with either Ce3+, La3+, Nd3+ or a mixture of rare earth elements (MRE) supplemented. After 20 d culture, moderate concentrations of Ce3+, La3+ and MRE can promote cell growth and flavonoids biosynthesis, while Nd3+ presented an inhibitting effect. Ce3+ at 0.025 mmol/L, gave the highest cell dry weight (17.7 g/L) and flavonoids production (942 mg/L) with both NAA and 6-BA in the culture medium. They were 34% and 67% higher than those without Ce3+ addition, respectively. Ce3+ at 0.005~0.05 mmol/L or the mixture of rare earth elements at 0.01~0.025 mmol/L, can substitute for 6-BA in promoting cell growth and the biosynthesis of total flavonoids of S. medusa while without 6-BA in the culture medium. When NAA were removed from the culture medium, none of the four rare earth elements can substitute for it in promoting S. medusa cell growth and the flavonoids biosynthesis. The kinetic curves of cell biomass, flavonoids production, residual sugar, NH4+ and NO3- concentration with or without 0.025 mmol/L Ce3+ in the culture medium were also obtained. The mechanism of the promotion effect of Ce3+ on cell growth and the biosynthesis of total flavonoids of Saussurea medusa was explained in some degree.