Toxicological evaluation of bioengineered salidroside produced by a novel method.

Area of Science:

• Biochemistry and Toxicology
• Natural Product Chemistry
• Food Safety

Background:

• Salidroside, a phenolic glycoside from Rhodiola plants, requires safety validation for food use.
• No prior safety assessments exist for salidroside produced via recombinant yeast fermentation.
• Ensuring the safety of novel food ingredients is crucial for consumer protection.

Purpose of the Study:

• To evaluate the genetic toxicity and repeated oral dose toxicity of biosynthetically derived salidroside in rats.
• To establish the safety profile of fermentation-produced salidroside for potential food applications.
• To provide the first comprehensive safety data for this novel ingredient.

Main Methods:

• Conducted three standard genotoxicity assays (bacterial reverse mutation, in vitro chromosomal aberration, and in vivo micronucleus tests).
• Performed 14-day and 90-day repeated oral dose toxicity studies in rats (both sexes).
• Determined the No Observed Adverse Effect Level (NOAEL) based on toxicological endpoints.

Main Results:

• Salidroside demonstrated no evidence of genotoxicity across all assays.
• In the 14-day study, no significant toxicological effects were observed up to 2000 mg/kg bw/day, establishing the NOAEL at this dose.
• In the 90-day study, the NOAEL was conservatively set at 1000 mg/kg/day due to minor, non-statistically significant findings in some female rats at higher doses.

Conclusions:

• Fermentation-derived salidroside is not genotoxic.
• The compound exhibits a favorable safety profile with high NOAELs in repeated dose toxicity studies in rats.
• These findings support the safety of using biosynthetically produced salidroside in food products.