Time reduction of vitamin B(6) and inositol assay by using lyophilized Saccharomyces cerevisiae ATCC 9080.
The purpose of this study was to improve the efficiency of the microbiological assays for vitamin B(6) and inositol by using lyophilized cells from Saccharomyces cerevisiae ATCC 9080. The use of lyophilized cells as an inoculum was assessed to avoid time-consuming processes like cell precultivation and washing. The authors also examined the effects of various protectants such as skim milk, lactose, maltose, and trehalose on the assay. The viable cell counts of the lyophilized cells were approximately equal. The standard curves for vitamin B(6) and inositol concentrations obtained using lyophilized cells with maltose and intact cells gave similar linear ranges. Furthermore, the measured vitamin concentrations of the standard reference material 1849 were in the range of the established values. Therefore, lyophilized cells with maltose are potential alternative inocula for the turbidimetric method. This will increase the overall convenience associated with microbiological assays.
Department of Food Function and Labeling, National Institute of Health and Nutrition, 1-23-1 Toyama, Tokyo 162-8063, Japan.
Harutoshi
H
Tsuda
Teruki
T
Matsumoto
Yoshiko
Y
Ishimi
D000818:Animals; D005504:Food Analysis / Q000379:methods*; D005612:Freeze Drying; D007294:Inositol / Q000032:analysis*; D007785:Lactose; D008320:Maltose; D008892:Milk; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000254:growth & development; D013997:Time Factors; D014199:Trehalose; D025101:Vitamin B 6 / Q000032:analysis*
D007294:Inositol; D008320:Maltose; D025101:Vitamin B 6; D014199:Trehalose; D007785:Lactose