Improvement of the cell volume of Candida protoplast fusion blankii through

SUMMARY The yeast Candida blank# ESP-94, capable of utilizing xylose as substrate, was isolated for the production of single-cell protein (SCP) on bagasse hydrolysates. However, the small cell volume of strain ESP-94 would complicate harvesting of the cells during a continuous fermentation process. Auxotrophic mutants of strain ESP-94 were generated and intraspecific protoplast fusion experiments performed in an attempt to increase the cell volume of strain ESP-94. The fusion products were characterised with respect to cell volume, DNA content and genetic stability. Six genetically stable fusants with bigger cell volumes and higher DNA contents were obtained. One such fusant, fnsant F 17, had a cell volume 3-times that of strain ESP-94, while exhibiting similar growth rates to strain ESP-94 on D-xylose as carbon source.