Relationship between fumonisin B1 and folic acid levels in foods and the folic acid concentration in human serum

Abstract

In the present study, folic acid and fumonisin B1 (FB1) levels were determined in corn flour consumed by 24 volunteers, residents in a university campus in São Paulo State, as well as its relationship with folic acid in serum of individuals. Analyses of folic acid and FB1 in corn flour were performed by high-performance liquid chromatography (HPLC), while the determination of folic acid in serum was accomplished using an immunoassay kit. FB1 was detected in 100% of corn samples, at levels ranging from 142 to 3,037 µg kg-1 (which means: 738 ± 591 µg kg-1). The concentrations of folic acid in corn flour samples ranged from < 0.3 µg kg-1 (limit of quantification) to 1,705 µg kg-1, with a mean of 713 ± 435 µg kg-1, which represents 47% of the minimum required by National Agency of Health Surveillance (ANVISA) for corn flour commercially available. The levels of folic acid in human serum samples ranged from 6.7 to 24.0 ng mL-1 (meaning: 13.4 ± 5.4 ng mL-1). No correlations were observed (p < 0.05) between the folic acid levels in serum of individuals and the concentrations of FB1 or folic acid in corn flour samples. Further studies are needed to estimate the total intake of FB1 in the diet to assess the effects fumonisins on the absorption of folic acid in the individuals evaluated.