Fukuronori (Gloiopeltis furcata) extract: 90-day dietary toxicity study inF344 rats

Fukuronori extract (FE), which is mainly composed of polysaccharides, and i s an extract of the seaweed Gloiopeltis furcata, is permitted for use as a food thickening agent by the Ministry of Health and Welfare, Japan. In orde r to study the subchronic toxicity of FE, F344 rats of both genders were ad ministered FE at concentrations of 0% (basal diet, control group), 0.5%, 1. 5% and 5.0% in basal powder diet for 90 days, and observation of general co ndition, recording of body weight and food consumption, examination of hema tology and blood chemistry, measurement of organ weight, and pathological e xamination were performed. Food consumption tended to increase in both sexe s given FE at 1.5% and 5.0% throughout most of the experimental period. Thi s was, however, considered not to be a toxic effect because the differences in body weight were small. Total cholesterol and triglycerides in serum de creased significantly (p<0.05) and not significantly, respectively, in male s of the 5.0% group. These changes were considered to be related to the int ake of FE, but the differences were slight and within physiological ranges. Hematological and pathological examination revealed neither any particular adverse effect nor any significant difference from the control. Hence, die tary intake of 5.0% of FE, 3,362 mg/kg/day for males and 3,594 mg/kg/day fo r females as mean daily intake, for 90 days was considered to be a no obser vable adverse effect level in rats.