Acute and 13-week subchronic toxicological evaluations of turanose in mice

Abstract

Background/objectives: Turanose, α-D-glucosyl-(1→3)-α-D-fructose, is a sucrose isomer which naturally exists in honey. To evaluate toxicity of turanose, acute and subchronic oral toxicity studies were conducted with ICR mice.

Materials and methods: For the acute oral toxicity study, turanose was administered as a single oral dose [10 g/kg body weight (b.w.)]. In the subchronic toxicity study, ICR mice were administered 0, 1.75, 3.5, and 7 g/kg b.w. doses of turanose daily for 13 weeks.

Results: No signs of acute toxicity, including abnormal behavior, adverse effect, or mortality, were observed over the 14-day study period. In addition, no changes in body weight or food consumption were observed and the median lethal dose (LD₅₀) for oral intake of turanose was determined to be greater than 10 g/kg b.w. General clinical behavior, changes in body weight and food consumption, absolute and relative organ weights, and mortality were not affected in any of the treatment group for 13 weeks. These doses also did not affect the macroscopic pathology, histology, hematology, and blood biochemical analysis of the mice examined.

Conclusion: No toxicity was observed in the acute and 13-week subchronic oral toxicology studies that were conducted with ICR mice. Furthermore, the no-observed-adverse-effect level is greater than 7 g/kg/day for both male and female ICR mice.

Keywords: ICR mice; LD50; NOAEL; Toxicity; turanose.

Fig. 1. Chemical structure of turanose (α-D-glucopyranosyl-(1→3)-α-D-fructopyranose)

Fig. 2. Mean body weight (g) and food consumption of male and female ICR mice administered turanose for 13 weeks.

Changes in body weight for the male (A) and female (B) mice administered turanose or distilled water over the experimental period are presented. Food consumption for the male (C) and female (D) mice over the experimental period is also presented. All data were analyzed using one-way ANOVA followed by Tukey's Honestly Significant Difference (HSD) post hoc test for multiple comparisons. The values are expressed as the mean ± SD (n = 5 in each group except the female 3.5 g/kg b.w. group which only had 4 mice/group due to the death of one animal). The group data are labeled according to the doses they received, expressed as g of turanose per kg b.w. ^*shows significant difference between 0 and 7 g/kg b.w. group. ^**shows significant difference between 0 and 3.5 g/kg b.w. group.

Fig. 3. Histopathological assessment of the liver and kidney of mice from the subchronic study.

The sections were from the control and mice treated with 7 g/kg b.w. for 13 weeks. Liver (A-D) and kidney (E-H) were observed for the histopathological analysis (magnification × 200). There were no significant changes related to the treatment when compared with the control group. Each picture represents one of five animals by each group (n = 5 per group). A and E; control group (male), B and F; 7 g/kg/day turanose-treated group (male), C and G; control group (female), D and H; 7 g/kg/day turanose-treated group (female). HE stain, bar = 100 um.