RESUMEN
To study the effect of the osmotic stress in the microenvironment on the growth and metabolism of the encapsulated cells under aerobic condition, Osmo-sensitive yeast Y02724 and high-osmotic resistant yeast Hansel were used as models to explore the growth and metabolism state of the cells cultivated inalginate-chitosan-alginate (ACA) microcapsules. The changes of the yeast cells' specific growth rate, maximum product quantity and the secretion of ethanol and glycerol were analyzed. For Y02724, the yield of ethanol was increased in the ACA microenvironment compared to suspension cultivation. For Hansel, the maximum growth speed of microencapsulated cultivation had no obvious difference compared to the suspension cultivation. Moreover, after encapsulation, the production of glycerol was decreased for both Y02724 and Hansel compared to suspension cultivation. In conclusion, osmotic stress existed in the ACA microcapsules and affected the growth and metabolism of the cells.