Safety Assessment of Indigenous Probiotic Strain Lactobacillus plantarum Dad-13 Isolated from Dadih Using Sprague Dawley Rats as a Model

Lactobacillus plantarum Dad-13 is a probiotic candidate from dadih, a traditional fermented buffalo milk from West Sumatera, Indonesia. This study aimed to evaluate safety aspects of L. plantarum Dad-13 in high dose consumption on Sprague Dawley rats. Two treatment groups were fed with 1011 CFU/mL/day of L. plantarum Dad-13 for 14 and 28 days respectively. Two placebo groups were fed with 1 mL skimmed milk per day for 14 and 28 days and a fifth, untreated group used as control. Feed intake and body weight were monitored, while blood samples and mesenteric lymph node (MPN) organs were dissected. Organ weight, leukocyte profiles, glutamic-oxaloacetic transaminase (GOT) activity, plasma malondialdehyde (MDA) concentration and intestinal morphology were measured. Microbial analyses were conducted on fecal matter, digesta, blood and organs. Results showed that consumption did not negatively affect general health, organ weight, leukocyte profiles, GOT activity, MDA concentration and intestinal morphology. Numbers of L. plantarum in treated rats’ feces were significantly increased, indicating its survival in gastrointestinal tracts. Bacteria in the blood and organs of both groups were identified using rep-PCR with BOX A1R primer, which revealed that it was not identical to L. plantarum Dad-13. Thus, L. plantarum Dad-13 did not translocate in the organs and blood of rats. Therefore, L. plantarum Dad-13 is suggested as likely to be safe for human consumption.