Safety evaluation of Bacillus coagulans SNZ 1969 in Wistar rats

Bacillus coagulans SNZ 1969 is a rod-shaped, slightly acidophilic, gram-positive, spore forming and highly resilient bacteria. B. coagulans SNZ 1969 has GRAS (Generally Recognized As Safe) status for use as a probiotic in foods (US FDA number GRN-597). The present study was aimed to assess the safety of a proprietary strain Bacillus coagulans SNZ 1969 by conducting acute and sub-acute 28 days repeated dose oral toxicity studies in Wistar Rats. In the acute toxicity study, the rats were orally fed with 2000 mg/kg body weight (BW) (5 × 10¹¹ CFU/g) of B. coagulans SNZ 1969 as a single dose to determine the LD50 values. In the sub-acute repeated dose toxicity study, six groups of experimental rats received 250, 500, 1000 mg/kgBW/day (5 × 10¹¹ CFU/g) of the test item for 28 consecutive days. The control animals received only water. Four groups of rats were sacrificed after 28 days and the remaining two groups were kept as recovery groups and sacrificed after 42 days. The results of these study indicate that there were no treatment related changes in any of the parameters studied i.e. clinical signs, body weight, food intake, urinalysis, hematological examinations, clinical biochemistry, gross pathology and histopathology after 28 days of repeated administration. Based on the results it was concluded that the LD50 of Bacillus coagulans SNZ 1969 is more than 2000 mg/kg body weight and the NOAEL derived from this study was 1000 mg/kg/day for 28 days, this corresponds to the 5 × 10¹¹ CFU/kg.