Safety assessment of the indigenous probiotic strain Lactiplantibacillus plantarum subsp. plantarum Kita-3 using Sprague–Dawley rats as a model

Lactiplantibacillus plantarum subsp. plantarum Kita-3 is a candidate probiotic from Halloumi cheese produced by Mazaraat Artisan Cheese, Yogyakarta, Indonesia. This study evaluated the safety of consuming a high dose of L. plantarum subsp. plantarum Kita-3 in Sprague-Dawley rats for 28 days. Eighteen male rats were randomly divided into three groups, such as the control group, the skim milk group, and the probiotic group. Feed intake and body weight were monitored, and blood samples, organs (kidneys, spleen, and liver), and the colon were dissected. Organ weight, hematological parameters, serum glutamic oxaloacetic transaminase (SGOT), and serum glutamic pyruvic transaminase (SGPT) concentrations, as well as intestinal morphology of the rats, were measured. Microbial analyses were carried out on the digesta, feces, blood, organs, and colon. The results showed that consumption of L. plantarum did not negatively affect general health, organ weight, hematological parameters, SGOT and SGPT activities, or intestinal morphology. The number of L. plantarum in the feces of rats increased significantly, indicating survival of the bacterium in the gastrointestinal tract. The bacteria in the blood, organs, and colon of all groups were identified using repetitive-polymerase chain reaction with the BOXA1R primers and further by 16S rRNA gene sequencing analysis, which revealed that they were not identical to L. plantarum subsp. plantarum Kita-3. Thus, this strain did not translocate to the blood or organs of rats. Therefore, L. plantarum subsp. plantarum Kita-3 is likely to be safe for human consumption.