硝普钠对青钱柳悬浮细胞三萜合成的影响

Effect of Sodium Nitroprusside on the Biosynthesis of Triterpenic Acids in Suspended Cultured Cyclocarya paliurus Cells

本文采用植物细胞工程技术建立青钱柳细胞悬浮培养体系，以硝普钠为外源诱导物对其三萜的合成进行诱导，从硝普钠的浓度、添加时间和持续作用时间三个方面系统地研究了硝普钠对青钹柳悬浮细胞生长、总三萜酸积累及代表性三萜酸合成的影响，以期为植物细胞培养生产三萜酸类化合物提供参考。10~50μmol／L的硝普钠对悬浮细胞的生长影响不大，但对三萜合成的诱导作用也不明显；150μmol／L的硝普钠有效地促进了三萜的合成且对细胞生长影响较小；200μmol／L以上的浓度则对细胞生长有较强的抑制作用；接种后的第8d添加150μmol／L硝普钠、持续作用4d后收获效果最佳，总三萜酸产量可达1228．74mg／L，为对照组的2．14倍，五种代表性三萜酸中以熊果酸（UA）和齐墩果酸（OA）的变化最为明显，分别比对照组提高了2．28倍和2．48倍。研究结果表明，外源添加硝普钠能有效地促进青钱柳悬浮细胞三萜酸的合成。

Cyclocaryapaliurus cell suspension culture was established in this paper, and sodium nitroprusside was added as an extraneous inducer to stimulate the biosynthesis of triterpenic acids. The effects of sodium nitroprusside in terms of concentration, adding time and inducement duration on the cells growth, total triterpenic acids accumulation, and the biosynthesis of five representative triterpenic acids were investigated. The results showed that 10~50 μmol/L sodium nitroprusside had little effect on the growth of Cyclocarya paliuru cells, and little stimulant effect on the biosynthesis of triterpenic acids. 150μmol/L sodium nitroprusside was suitable for the accumulation of triterpenic acids, and had little effect on the cells growth. High concentrations （200~500 μmol/L） of sodium nitroprusside inhibited the growth seriously. The highest production of triterpenic acids was obtained when 150μmol/L sodium nitroprusside was added at the 8 th day after inoculation and continuous inducement for 4 days. Under this optimal conditions, the production of total triterpenic acids was as higher as 1228.74 mg/L, which was 2.14 times higher than that of the control group. And the output of ursolic acid and oleanolic acid increased more obviously among the five representative triterpenic acids of this cells, which was 2.28 and 2.48 times, respectively, higher than the control group. Our researches indicated that extraneous sodium nitroprusside effectively increased the biosynthesis of triterpenic acids in suspended cultured Cyclocaryapaliuru cells.