Toxicological evaluation of bioengineered salidroside produced by a novel method

Salidroside is a naturally occurring phenolic glycoside primarily found in the roots and tubers of plants in the Rhodiola genus. The safety profile of the compound is a non-negotiable prerequisite for the applications of salidroside in food. No safety assessments of salidroside produced using recombinant Saccharomyces cerevisiae fermentation have been identified. To evaluate the safety of this biosynthetically derived salidroside, the research systematically assesses the potential for genetic toxicity and repeated dose oral toxicity in rats, providing the first comprehensive safety data for this novel fermentation-based product. The substance did not exhibit any evidence of genotoxicity in all three assays performed to assess this endpoint. Subsequently, the repeated oral dose toxicity of salidroside in rats was assessed over a period of 14 days and 90 days. Salidroside did not induce any significant toxicological changes in either sex at a dose of 2000 mg/kg bw/day over a 14-day period. The No Observed Adverse Effect Level (NOAEL) was determined to be 2000 mg/kg bw/day for the 14-day study. In the 90-day rat study, elevations in ALT and AST occurred in a few female rats administered salidroside at 1500 mg/kg/day. However, the group means lacked statistical significance (p > 0.05, ALT p = 0.72, AST p = 0.12). Due to a few additional sporadic idiosyncratic findings at 1500 mg/kg bw/day, the NOAEL for the 90-day study was conservatively established at 1000 mg/kg/day for both sexes of rats.