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Aims:The purpose of the present investigation was to develop a novel method for cell immobilization. Methods and Results: Aureobasidium pullulans cells were mixed with an alginate solution, and the mixture was extruded to form small gel beads as hydrated-immobilized cells. The beads were then placed at )15°C for 6-24 h to induce freeze-dehydration. The freeze-dehydration resulted in shrinkage of beads as a result of water removal reducing bead volume by 82% and bead weight by 85%. The dehydrated beads were successfully used for the production of fructo-oligosaccharides in a model reactor system. Conclusions: Dehydrated beads may provide some commercial advantages over conventional immobilized cells. Significance and Impact of the Study: This study shows that bioreactor performance can be improved up to two times by the use of the dehydrated beads.

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PACS : 68.55.Jk; 81.15.Gh We have grown the GaN thin films on silicon substrates using the newly developed single source precursors by thermal MOCVD method. Highly oriented GaN thin films in the [002] direction with hexagonal structure were deposited on Si(111) substrates at 800 C and 1 Torr with Triazido(triphenylphosphine oxide) gallium. XRD pattern and pole-figure analysis proved that the highly oriented GaN film has a single-crystalline nature. PL data of this film show that a strong emission peak but with some large FWHM of 100 meV could be observed at 3.4 eV (365 nm). Patterning of GaN thin films was also successfully performed by MOCVD onto Si(100) substrates of which surface was modified by organic thin film. The organic thin film of SAMs was in first obtained by mCP method. The deposition of GaN thin films has then been carried out onto those modified Si(100) substrates using the single molecular precursor by thermal MOCVD without carrier and bubbler gases. In addition, a buffer layer of thin TiO 2 film was applied into the modified Si(100) substrates to understand a possibility of selective deposition of GaN film.