Euglena gracilis is a single-celled organism capable of photosynthesis and heterotrophy. Euglena sp. have long been studied in the laboratory for its metabolic pathways, cell motility, and ease of culture. The safety of E. gracilis strain eu029 (EG029) for use as a food ingredient was assessed in a bacterial reverse mutagenesis assay (Ames), rec assay, in vivo micronucleus assay, acute toxicity study in mice, 13-week toxicology in rats, and a teratology study in mice and rats. EG029 was not genotoxic. The No Observed Adverse Effect Level (NOAEL) in the 13-week study was greater than 1000 mg/kg/day, the highest dose tested. Teratogenicity studies did not find any defects in fetal development or effects to maternal health in rats at 1000 mg/kg/day, the highest dose tested.

AlphaGOS®, an alpha-galacto-oligosaccharides product, is a mixture of bi-, tri- and tetrasaccharides derived from oligosaccharides in the raffinose family of oligosaccharides (RFOs), naturally occurring plant-derived sugars. RFOs are alpha α-1,6-linked chains of D-galactose attached to the 6-position of D-glucose and differ from the currently commercially available beta-galacto-oligosaccharides products in the chirality and glyosidic bonds. In order to determine the safety of AlphaGOS, rats were given 2000 mg AlphaGOS/kg/day daily via gavage over 90 days. Daily assessments of the animals showed no adverse clinical signs. No adverse treatment-related changes in feed consumption, body weight, clinical chemistry or hematology were noted. There were no adverse treatment-related changes in organ weights, gross or histopathology. Given these findings, it can be concluded that the no observed adverse effect level for AlphaGOS is greater than 2000 mg/kg/day.