title: Analytical methods and stability assessment of liquid yeast derived sucrase.
abstract: Two independent analytical methods for determining the activity and stability profile of liquid yeast derived sucrase (YS) were established and validated in order to conduct preliminary stability studies as a function of temperature. The methods included a hexokinase-based (HK) enzymatic assay for determining the formation of glucose upon hydrolysis of sucrose by YS, and a direct polarimetric procedure to quantitate YS hydrolysis of sucrose. Both assays were validated with respect to YS dilution, incubation time, sucrose or glucose concentration, linearity of response and within- and between-day variability. A preliminary stability study was conducted over a 24 week period with liquid YS samples stored at -20, 4, 30, 40 and 50 degrees C. Enzymatic activity was monitored as a function of time using both the HK and polarimetric assays. Liquid YS samples stored at -20, 4 and 30 degrees C retained 100% activity after 24 weeks storage, while the samples stored at 40 degrees C lost approximately 70% activity over the same storage period and samples stored at 50 degrees C lost approximately 95% activity after 12 weeks storage. The two methods of analysis gave consistent results over the course of the study.
authors.affiliation: Department of Pharmaceutics, Victorian College of Pharmacy, Monash University, Parkville, Australia.
authors.forename: K A
authors.initials: KA
authors.lastname: McIntosh
authors.forename: S A
authors.initials: SA
authors.lastname: Charman
authors.forename: L A
authors.initials: LA
authors.lastname: Borgen
authors.forename: W N
authors.initials: WN
authors.lastname: Charman
mesh_terms: D002623:Chemistry Techniques, Analytical / Q000379:methods*; D004355:Drug Stability; D005658:Fungi / Q000737:chemistry*; D006593:Hexokinase / Q000378:metabolism*; D011048:Polarography; D015203:Reproducibility of Results; D013393:Sucrase / Q000032:analysis*; D013696:Temperature; D013997:Time Factors
chemical_list: D006593:Hexokinase; D013393:Sucrase