The authors regret that the description of the parental Escherichia coli (E. coli) strain and the list of enzymes used in the multi-enzyme synthesis of 6’-sialyllactose (6’-SL) sodium salt in the Introduction were incomplete and wish to clarify these points to improve scientific accuracy and to avoid potential misunderstanding by readers. This clarification does not alter the design, conduct or interpretation of the in vitro or in vivo toxicological studies, and therefore does not affect the overall conclusions regarding the safety of 6’-SL sodium salt produced by the novel manufacturing process.
The corrected version of the last paragraph of “Introduction” is presented below:
The results of genetic toxicity tests and acute and 26-week repeated dose oral toxicity studies in rats for the safety evaluation of 6′-SL sodium salt produced by a new process are described in this publication. Similar tests are typically conducted for candidate food ingredients; however, in this case, the duration of the repeated dose oral toxicity study in rats exceeds the generally recommended 13-week study period. The synthesis of 6′-SL sodium salt employs a multi-enzyme reaction utilizing polyphosphate kinase (PPK), CMP-N-acetylneuraminic acid synthetase, N-acetyl-D-glucosamine-2-epimerase, N-acetylneuraminic aldolase, NMP kinase and α2,6-sialyltransferase. These enzymes were derived from β-D-galactosidase-deficient strains of E. coli K-12 ∆lacZ, which originated from the non-pathogenic E. coli K-12 W3110 lineage. This production method differs from that reported by Gurung et al. [6] in its use of a nonmetallic phosphate donor and PPK as an enzyme, instead of acetate kinase (ACK) and NMP kinase instead of CMP kinase.
The authors would like to apologise for any inconvenience caused.
DOI of original article:10.1016/j.toxrep.2025.102101