Advanced search×

Safety and risk assessment of the genetically modified Lactococci on rats intestinal bacterial flora

Int J Food Microbiol 142(1-2):6 (2010) PMID 20619909

The interaction between Lactococcus lactis NZ9000/pNZPNK and intestinal microflora was evaluated as a method to assess safety of genetically modified microorganisms (GMMs). L. lactis NZ9000/pNZPNK is one kind of GMM and able to produce the intracellular subtilisin NAT (nattokinase) under induction with nisin. The host strain L. lactis NZ9000 was a generally recognized as safe (GRAS) microorganism. Six groups of Wistar rats were orally administered with L. lactis NZ9000/pNZPNK and L. lactis NZ9000 for 6weeks. Fecal and cecal contents were collected to determine the number of L. lactis NZ9000, L. lactis NZ9000/pNZPNK, Lactobacillus, coliform bacteria, beneficial bacteria Bifidobacterium and harmful bacteria Clostridium perfringens. The liver, spleen, kidney and blood were evaluated for the bacterial translocation. After 6weeks consumption with GM and non-GM Lactococcus, no adverse effects were observed on the rat's body weight, hematological or serum biochemical parameters, or intestinal microflora. The bacterial translocation test showed that L. lactis NZ9000/pNZPNK did not translocate to any organ or blood. Bifidobacterium was significantly increased in feces after administration of both Lactococcus strains (L. lactis NZ9000 and L. lactis NZ9000/pNZPNK), while C. perfringens remained undetectable during the experiment. These results suggested that L. lactis NZ9000/pNZPNK could be safe in animal experiments and monitoring of the interaction between test strains and intestinal microflora might be applied as a method for other GMM safety assessments.

Copyright © 2010 Elsevier Ltd. All rights reserved.

DOI: 10.1016/j.ijfoodmicro.2010.06.018
Version: za2963e q8zad q8zb4 q8zca q8zd9 q8zed q8zf6 q8zgb

Similar articles you may find interesting…

  1. Effects of nattokinase, a pro-fibrinolytic enzyme, on red blood cell aggregation and whole blood viscosity.

    Clin Hemorheol Microcirc 35(1-2):139-42 (2006) PMID 16899918

    We have begun to assess the effects of the enzyme on RBC aggregation and blood viscosity. Blood samples were incubated with nattokinase (final activities of 0, 15.6, 31.3, 62.5 and 125 units/ml) for 30 minutes at 37 degrees C. RBC aggregation was measured using a Myrenne MA-1 aggregometer and blood...
  2. Preparation and Application of Novel EOPO−IDA−Metal Polymer as Recyclable Metal Affinity Ligand in Aqueous Two-Phase Systems

    Ind Eng Chem Res 45(5):1774-1779 (2006)

  3. Characterization of Bacillus subtilis strains in Thua nao, a traditional fermented soybean food in northern Thailand.

    Lett Appl Microbiol 43(3):237-42 (2006) PMID 16910925

    Production of amylase, protease, subtilisin NAT (nattokinase), and gamma-polyglutamic acid (PGA) by the Bacillus subtilis strains in Thua nao was measured. Productivity of protease NAT by these strains tended to be higher than by Japanese commercial natto-producing strains. Molecular diversity of is...