Studies On Growth And Metabolism Of Encapsulated Taxus Cuspidata

In order to make a deep understanding of growth and metabolism ofencapsulated cells, Taxus cuspidate cells were immobilized in variousalginate-chitosan beads. By alternating matrix density, inoculums, subculture, weanalysis reasons for particular cell physiology, and made a comprehensive study. Wegot results as following: Immobilization effected cells most on mass diffusion, and cells viability wasreduced. Liquefied beads and solid beads without chitosan, as improved immobilizedmeasure, maintained the viable cell ratio better, enhanced cells metabolism, andincreased absorption of sugar and other nutrition. They also stimulated immobilizedcells,so cells membrane penetration increased, extracellar protein improved and pH ofmedium fell. And solid beads without chitosan made the augment of cell penetrationless than liquefied beads. Solid beads with chitosan membrane or not strengthenedsecretion and accumulation of phenol more than liquefied beads. Subculture in cell lag stage in this experiment did not improve viable cells ratioto get more secondary metabolite production. Encapsulated cells in subcultureexhibited a few physiology behaviors same like original culture. Denser matrix stimulated encapsulated cells more; as a result phenolicsaccumulation was enhanced, and conductivity in medium increased. But densermatrix did harm to cells in long stage culture. So moderate matrix density(20g/L-30g/L) benefited cells to maintain high viability.Inoculums impacted viablecells ratio, nutrition consumption with different level in different period. In earlyculture time, the impaction was tiny. In lag stage, viable cells ration decreased wheninoculums increased. High inoculums stimulated cells more, and released moreintracellar ions. More inoculums delayed the peak of phenolics accumulation. Andphenolics accumulation had liner correlation with inoculums in lag stage. Alginate-chitosan immobilization enhanced medium conductivity, because thebeads impacted cell penetration and made more ions released out. This resulted bothfrom shearing and flushing to cells on the beads surface and impaction of cells ininner beads.