A 90-day oral (dietary) toxicity study of arruva, an R, R-monatin salt isomer, in Crl:CD-1(ICR) mice

R,R-Monatin [2R,4R- isomer of 2-hydroxy-2-(indol-3-ylmethyl)-4-aminoglutaric acid] is one of four natural constituent isomers in the root bark of Sclerochitin ilicifolius; and "arruva" is the common/usual name that is proposed to represent R,R-monatin salt forms, which have potential use as high potency sweetener food ingredients. In the present study, groups of male and female Crl:CD-1(ICR) mice were exposed to 0 (control), 5000, 10,000, 20,000, or 35,000ppm of arruva in the diet for 90days. There were no toxicologically relevant clinical or histopathological findings in any of the test article-treated groups. Significantly lower mean body weights and cumulative body weight gains were noted in the 35,000ppm group when compared to the control group. Mean body weights in the 35,000ppm group males and females were 9% and 7% less than the control group, respectively, at week 13. In the absence of observations associated with systemic toxicity and in consideration of the magnitude of body weight difference, these effects were not considered toxicologically significant. Based on the results of this study, the dietary no-observed-adverse-effect level (NOAEL) of arruva for 90days in male and female mice was 35,000ppm (equivalent to an exposure level of 5764 and 8013mg/kg bw/day, respectively).