Supplementation with engineered Lactococcus lactis improves the folate status in deficient rats

LEBLANC J.G.; SYBESMA W,; STARRENBURG M.; SESMA F.; DE VOS WM; G. SAVOY DE GIORI; HUGENHOLTZ J.

NUTRITION

Elsevier

Año: 2009

0899-9007

Objective The aim of this study was to establish the bioavailability of different folates produced by  engineered Lactococcus (L.) lactis strains using a rodent depletion-repletion bioassay.  Research Methods & Procedures Rats were fed a folate-deficient diet, which produces a reversible subclinical folate  deficiency, supplemented with different L. lactis cultures which were added as the only source of folate. Three bacterial strains that over-expressed either the folC, folKE or  folC+KE genes were used. These strains produce folates with different polyglutamyl tail  lengths. The growth response of the rats and the concentration of folates in different organs  and blood samples were monitored.  Results The folate produced by the engineered strains was able to compensate the folate depletion  in the diet and showed similar bioavailability compared to commercial folic acid that is  normally used for food fortification. Folate concentrations in organ and blood samples  increased significantly in animals that received the folate producing strains compared to  those that did not receive bacterial supplementation. Hematological studies also showed  that the administration of the L. lactis strains was able to revert a partial megaloblastic  anemia caused by folate deficiency. No significant differences were observed in  bioavailability of folates containing different glutamyl tail lengths. Conclusions To our knowledge, this is the first study that demonstrated that folates produced by  engineered lactic acid bacteria represent a bioavailable source of this essential vitamin.