原位吸附和茉莉酸甲酯联合使用显著提高中国红豆杉细胞云南紫杉烷c的生产

Enhanced production of taxuyunnanine c in cell suspension cultures of Taxus chinensis by methyl jasmonate elicitation and in situ absorption

摘要:

本实验所用的中国红豆杉细胞悬浮培养体系中，云南紫杉烷c (Tc) 是主要的次生代谢产物，该化合物有类神经生长因子活性，提高其产量是进一步规模化生产的前提。本研究考察了原位吸附和茉莉酸甲酯 (MJA) 联合调控提高Tc产量的可能性。在培养的第7天加入浓度为100 μmol/L的MJA虽然会使细胞的生物量下降10％~30％，但是单位细胞内Tc含量和Tc产量均有显著提高，分别是对照的3.6和3.3倍。吸附剂XAD-7在不同时间加入对Tc 的合成影响显著。在培养的第7天同时加入100 μmol/L的MJA和100 g/L的XAD-7会使细胞生物量增加，Tc产量显著提高。培养到第21天，Tc产量达477.37 mg/L，为对照的6.3倍，为只加MJA的1.9倍，其中94％的Tc被树脂吸附。实验结果表明，在MJA诱导高表达的过程中，吸附剂XAD-7的加入使细胞内代谢产物外泌，浓度降低，减轻产物反馈抑制现象，从而大幅度提高代谢物产量，有较好的生产前景。

Abstract:

A bioprocess intensification strategy that combines both elicitation and in situ absorption was developed to improve the production of taxuyunnanine C (Tc) in suspension culture of Taxus chinensis. When 100 μmol/L methyl jasmonate was added as an elicitor on Day 7, the Tc content and yield increased 3.6 and 3.3 times respectively, however the cell growth was reduced by 30%. Significant improvement in Tc yield was observed when an absorbent XAD-7 was added on different time of the culture period. The optimum Tc production was achieved when 100 g/L XAD-7 was added simultaneously with 100 μmol/L methyl jasmonate on Day 7. The maximum Tc yield of 477.4 mg/L was obtained on Day 21 of the culture, being 6.3-fold of the control and 1.9-fold of the 100 μmol/L methyl jasmonate treatment alone. In the combined treatment, 94% of the Tc produced were secreted outside of the cells and absorbed on XAD-7 absorbents. The results demonstrated that the process strategy combining elicitation and in situ absorption was effective to intensify the Tc biosynthesis via elicitation with the removal of product feedback inhibition via absorption, presenting a great potential in commercial applications.