Cell immobilization in k-carrageenan with tricalcium phosphate.

The objectives of this research were to investigate the growth of immobilized yeast cells in k-carrageenan gel and study the effect of trapping hydroxyapatite (tricalcium phosphate) crystals into the matrix. Using k-carrageenan, the final number of cells per milliliter of gel is at least an order of magnitude higher than free cells per milliliter of medium. A "cell retention" theory explaining this cell concentration difference was proposed. Coexistence of yeast cells and an additional agent such as tricalcium phosphate results in sustained viability through internal pH control, increased cell loading, greater settling velocity, and enhanced ethanol production.