Acute and Subacute Administration of Bacillus Subtilis UBBS-14 Probiotic Shows No Toxicity in Male and Female Sprague-Dawley rats

Abstract

Abstract Recently probiotics have been garnering a lot of attention due to their therapeutic potential in the management of various health ailments. Bacillus subtilis containing probiotics show several health benefits prominently against gastrointestinal tract disorders and diarrhoea. Herein, we examined the toxicity of Bacillus subtilis UBBS-14 probiotic following acute and subacute administration in male and female Sprague-Dawley rats, as per Organisation for Economic Cooperation and Development (OECD) 423 and 407 guidelines, respectively. The acute toxicity of Bacillus subtilis UBBS-14 was tested following single 5000 mg/kg (500 billion CFU/kg) administration via oral gavage. No mortality or adverse events were noted till 14 days post-treatment, this indicates that the LD50 of Bacillus subtilis UBBS-14 is > 5000 mg/kg after single administration. In subacute study, rats received a daily dosage of 100, 500 and 1000 mg/kg Bacillus subtilis UBBS-14 (containing 10, 50 and 100 billion CFU/kg, respectively) by oral gavage for 28 days. Rats in the recovery group were observed for an additional 14 days during probiotic-free period. No notable changes were seen in the morphology, weight and histopathology of the critical internal organs. The haematological parameters, biochemical parameters, electrolytes (sodium, potassium, chloride and calcium), and urine analysis results were within the range and comparable to that with vehicle-treated group. Thus, no-observed-adverse-effect level (NOAEL) for Bacillus subtilis UBBS-14 after 28-day subacute administration was found to be > 1000 mg/kg/day. As the results of acute and subacute treatment with Bacillus subtilis UBBS-14 did not show any adverse effects, this probiotic formulation may be safe for human consumption.