Developmental toxicity assessment of D-allulose produced by genetically engineered Escherichia coli

This study aims to evaluate the prenatal developmental toxicity potential of D-allulose produced by genetically engineered Escherichia coli in rats. Given the increasing use of D-allulose in food products, a thorough toxicological assessment is essential to ensure its safety. A prenatal developmental toxicity test in Sprague-Dawley rats was conducted in accordance with the OECD Guidelines Test No. 414 (prenatal developmental toxicity study) and GB 15193.14-2015 (National food safety standards teratogenicity test of the People's Republic of China). Pregnant female rats received repeated doses of 1250, 2500, and 5000 mg/kg bw D-allulose by gavage on Gestation Days (GD) 6-15. A vehicle control (distilled water) and a positive control (cyclophosphamide) were also included. On GD 20, pregnant rats were euthanized, and fetuses were examined for external, soft tissue and skeletal abnormalities. No treatment-related anomalies were observed, indicating that D-allulose did not exhibit prenatal developmental toxic effects. The No-Observed-Adverse-Effect-Level (NOAEL) was determined to be 5000 mg/kg/day.