Research on the Effect of Light Irradiation on Metabolite Production using Cultured Plant Cell

1)光照对咖啡细胞次生代谢物产生的影响为实现植物细胞培养的工业化应用，采用化学辐射计量法研究了光照对小粒咖啡细胞产生咖啡因的影响。阿拉比卡咖啡细胞的咖啡因产量在光的刺激下被贪婪地增加。在分批培养中增加咖啡因的产量需要大约6天的照射时间。在0.11J/L/S的低光照度下，咖啡因的产生显著增加，同时，提高照射率抑制了细胞的生长。结果表明，存在一个优化产量的光照度。由于长时间连续光照对细胞生长有很大的抑制作用，因此将培养分为两个阶段：光照下的产生期和黑暗中的生长期。2)细胞光吸收速率的估算。我们建立了一种新的方法来定量测定细胞悬浮液中光的透射率和反射率，并估算了细胞的光吸收速率，为光生物反应器的设计策略提供了有用的信息。3)光生物反应器的构建我们提出了吸附柱式培养系统，并取得了良好的效果。在鼓泡塔反应器中使用植物细胞的固定化细胞系统实现了更高的生产率和细胞生长。

1) Effect of light irradiation on the secondary-metabolite production of coffee plant cellsThe effect of light on caffeine production by Coffea arabica cells was investigated using chemical actinometry for the purpose of industrial application of plant cell cultures. Caffeine production by the Coffea arabica cells was greedy increased by light. About a six-day irradiation period was required to increase the caffeine production in a batch culture. Caffeine production significantly increased at a low light irradiation rate of 0.11 J/L/S. Meanwhile, cell growth was suppressed by increasing the irradiation rate. It was shown there was a light irradiation rate that optimized production. Since longterm continuous light greatly suppressed cell growth, the culture was divided into two stages : the production period in the light and the growth period in the dark. The high production and good growth were maintained for 65 days.2) Estimation of light adsorption rate by a cell.We developed a novel method for quantitative determination of the ratio of light transmission to reflection in cell suspension using chemical actinometry, and estimated light adsorption rate by a cell, which presents useful information for design strategy of photobioreactor.3) Construction of photo-bioreactorsWe proposed the culture system with adsorption column for the product removal and presented good results. Immobilized cell system using the plant cell in a bubble column reactor achieved higher productivity and cell growth.