Euglena gracilis and paramylon may have potential use as functional food ingredients in human and animal nutrition.

In vitro genotoxicity and 90-day subchronic oral toxicity study of E. gracilis and paramylon were tested.

E. gracilis was not genotoxic in a bacterial reverse mutation test and mammalian micronucleus test.

E. gracilis and paramylon showed no toxicity to rats at concentration tested up to 50,000 ppm for 90 days.