Abstract
Anhydrous amorphous raffinose and trehalose were examined their crystallinity in humid conditions by a powder X-ray diffractometer. The raffinose started to crystallize in the condition of 52% relative humidity at 35℃ after 49 hours and it crystallized completely after 304 hours. The trehalose crystallized completely in the same condition after 3 hours. Anhydrous amorphous raffinose is harder to crystallize than anhydrous amorphous trehalose. Glassy preservation of lactate dehydrogenase (LDH) was carried out in the humid conditions using these sugars as excipients. The enzyme in a trehalose system has a higher activity than in a raffinose system.
