Production of secondary metabolites in berry cell cultures

• Main Author: Dick, Marc
• Format: Master Thesis
• Language: English
• Published: Zurich University of Applied Sciences 2008
• Subjects: Arctic
• Online Access: https://cris.vtt.fi/en/publications/65d2ce46-636a-40c9-bf16-e88292725832

In this diploma thesis the scale up of arctic bramble suspension cultures from 30 mL to 1 L was carried out in shake flasks. Growth conditions were optimized, especially the optimal concentration of inoculated cells and shaking rate were evaluated. During the optimisation of the 200 mL arctic bramble suspension cultures in shake flasks maximally a specific growth rate of 0.0080 h-1 and a dry weight of 22 g L-1 were achieved. A concentration of the inoculum of 100 g L-1 and a shaking rate of 103 rpm were evaluated as the optimal cultivation condition. The 1 L suspension cultures were grown under the optimised conditions and achieved a specific growth rate of 0.0066 h-1 and a dry weight of 19.7 g L-1. During the growth of the 1 L culture dissolved oxygen was measured to be under 5 % and a limitation of oxygen was assumed. The growth of arctic bramble suspension cultures in the Wave bioreactor was investigated. The growth was monitored as usually by determining the fresh and dry weight, pH value, conductivity and sugar concentration and the dissolved oxygen. The 1 L arctic bramble suspension cultures grew well in the Wave bioreactor and achieved maximally a specific growth rate of 0.0109 h-1 and a dry weight of 21.3 g L-1. The dissolved oxygen supply in the Wave bioreactor was good and no limitation was observed. Finally the elicitation of suspension cultures performed with s-ABA to produce new phenolic compounds was studied. The suspension cultures in the bioreactor were elicitated with s-ABA at different growth phase points and the phenolic compounds were analysed by HPLC. The time point of the elicitation did not cause any changes to phenolic profiles. Three phenolic compounds kaempferol, ferulic acid and sinapic acid were identified in non-elicitated as well as in elicitated cultures according to retention times and characteristic maxima in the spectra. In elicitated cultures the concentration of the compounds decreased after the elicitation. However, kaempferol hexoside was detected only in s¬ABA elicitated ...