Safety evaluation of Whole Algalin Protein (WAP) from Chlorella protothecoides

Microalgae such as Chlorella spp., were once consumed as traditional human foods; now they are being developed as ingredients for modern diets. Whole Algalin Protein (WAP) from dried milled Chlorella protothecoides was evaluated for dietary safety in a 13-week feeding trial in rodents with genotoxic potential evaluated using in vitro and in vivo assays and the likelihood of food allergy potential evaluated via human repeat-insult patch test (HRIPT). In the subchronic study, rats consumed feed containing 0, 25,000, 50,000 or 100,000 ppm WAP for 92–93 days. No treatment-related mortalities or effects in general condition, body weight, food consumption, ophthalmology, urinalysis, hematology, clinical chemistry, gross pathology, organ weights, and histopathology occurred. Several endpoints exhibited statistically significant effects, but none was dose-related. The no-observed-adverse-effect level (NOAEL) was based on the highest WAP concentration consumed by the rats and was equivalent to 4805 mg/kg/day in males and 5518 mg/kg/day in females. No mutagenicity occurred in Salmonella typhimurium or Escherichia coli tester strains (⩽5000 μg/plate WAP) with or without mutagenic activation. No clastogenic response occurred in bone marrow from mice administered a single oral dose (2000 mg/kg WAP). Skin sensitization was not induced by WAP via HRIPT, indicating little potential for food allergy.