Safety Assessment of Enterocin LD3 Purified from a Food-Grade Enterococcus hirae LD3

Enterocin LD3, a bacteriocin produced by Enterococcus hirae LD3, was previously isolated from batter of Dosa and characterized for unique mass, sequence, stability and antimicrobial activity against pathogenic bacteria. In this study, safety assessment of enterocin LD3 was evaluated in cell lines and mice model. It does not show haemolysis up to 400 µg/mL and IC₅₀ was found to be 643.16 ± 6.75 µg/mL against human embryonic kidney (HEK-293) cell line. Enterocin LD3 was purified to homogeneity and applied intraperitoneally to male Swiss albino mice. The level of SGOT (149.5 ± 2.0 U/L), SGPT (68.7 ± 9.8 U/L), urea (25 ± 4.2 mg/dL) and creatinine (0.92 ± 0.1 mg/dL) were found to be in the normal range. In contrast, acetamiprid-treated mice (positive control) exhibited significantly higher level of SGOT (288.4 ± 38 U/L), SGPT (98.3 ± 31.1 U/L), urea (32.8 ± 4.7 mg/dL) and creatinine (2.4 ± 0.7 mg/dL). In addition, there were no significant changes observed during histopathological analysis of liver and kidney tissues after treatment of mice with enterocin LD3. Although, these are initial findings and need further investigations, it indicates safety profile of enterocin LD3 for its applications in food and clinical settings.