Subsequent products after antioxidant actions of beta-carotene and alpha-tocopherol have no Salmonella mutagenicity

In vitro genotoxicity assessment of functional ingredients: DHA, rutin and α-tocopherol

The in vitro genotoxicity of three compounds widely used as functional ingredients, docosahexaenoic acid (DHA), rutin and α-tocopherol, was assessed. A miniaturized version of the Ames test in Salmonella typhimurium TA97a, TA98, TA100, TA102, and TA1535 strains (following the principles of OECD 471), and the in vitro micronucleus test in TK6 cells (OECD 487) were performed. This strategy is recommended by the European Food Safety Authority for the in vitro genotoxicity assessment of food and feed. In addition, this approach was complemented with the in vitro standard and enzyme-modified comet assay (S9-/S9+) using hOGG1, EndoIII and hAAG in order to assess potential premutagenic lesions in TK6 cells. Rutin showed an equivocal response in the in vitro micronucleus test and also was a potent Salmonella typhimurium revertant inductor in the Ames test. DHA showed equivocal results in the in vitro micronucleus test. In this regard, DHA and rutin seemed to interact with the DNA at a chromosomal level, but rutin is also capable of producing frameshift mutations. No genotoxicity was observed in cells treated with α-tocopherol. This article complements the evidence already available about the genotoxicity of these compounds. However, more studies are needed in order to elucidate the consequences of their use as functional ingredients in human health.

An alpha-tocopherol dose response study in Paramecium tetraurelia

Vitamin E (D,L-alpha-tocopherol) was administered to Paramecium tetraurelia in doses of 10, 100, 1000 and 10,000mg/l throughout its clonal lifespan. ANOVA revealed significant differences in clonal lifespan between groups, whether lifespan was measured in total fissions, or in days (P<0.05). When mean clonal lifespan was measured in fissions the greatest difference was between the 1000mg/l alpha-tocopherol treatment at 382 fissions, and the ethanol control at 255.5 fissions. The greatest difference in mean clonal lifespan in days survived was between the 10,000mg/l alpha-tocopherol treatment at 292.5 days and the ethanol control at 76 days. ANOVA also revealed significant differences (P<0.05) in the initial cell fission rates between groups. At the 1000 and 10,000mg/l concentrations of alpha-tocopherol, a decrease in cell fission rates was apparent early in the lifespan, but these rates began to increase gradually during the late clonal lifespan. Although no clonal toxicity effects were found in terms of decreasing life-expectancy, the 1000 and 10,000mg/l treatment groups exhibited higher background mortality rates throughout their respective lifespans than did the control groups, which could represent a cytotoxic effect.