Safety evaluation of Chlorogonium capillatum (Chlamydomonadaceae) as a potential food for 28 days in rats.

Abstract

The safety of the alga Chlorogonium capillatum as a human food source was evaluated in a 28-day oral subacute toxicity study using rats. The freeze-dried powder of C. capillatum was orally administer to male and female rats in dosage of 1000 mg/kg/day for a period of 28 days. Neither mortality nor changes in general condition was observed in either the treatment group or the control group throughout the 28-day administration period. For males of the C. capillatum-administered group, there was significantly decrease in weight at 14-day and 28-day.  However, these changes were within the range of normality. In the hematological tests and serum biochemical tests performed at the time of completion of the end of the administration period, no influences of C. capillatum were observed. At autopsy, macroscopic observation of organs and tissues, and organ weight measurement at the end of the experimental period revealed no significant influences of C. capillatum feeding. In conclusion, considering the absence of adverse effects of C. capillatum in this 28-day oral subacute toxicity study, the non-observed adverse effect level (NOAEL) was estimated more than 1000 mg/kg/day of C. capillatum for both of male and female rats.