Safety Evaluation of Goat Milk Added with the Prebiotic Inulin Fermented with the Potentially Probiotic Native Culture Limosilactobacillus mucosae CNPC007 in Co-culture with Streptococcus thermophilus QGE: Analysis of Acute and Repeated Dose Oral Toxicity

Abstract

Despite functional goat milk products having emerged due to their importance for human nutrition and health, few studies have assessed the safety of consumption of goat dairy products containing potentially probiotic autochthonous lactic acid bacteria supplemented with prebiotic carbohydrates. Aiming this field, this study evaluated the safety of goat's milk fermented with Streptococcus thermophilus QGE, the autochthonous Limosilactobacillus mucosae CNPC007 culture, and the prebiotic inulin, through single- and repeated-dose oral toxicity tests (SDT and RDT, respectively) in animals. Ten female Swiss Webster mice were used for SDT evaluation - 2 groups, SDTc (20 mL/kg of filtered water) and SDTt (20 mL/kg of fermented milk) - and 40 Wistar rats for RDT - RDT3, RDT6, and RDT12 (treated with fermented milk at doses of 3 mL/kg, 6 mL/kg, and 12 mL/kg, respectively) and also RDTc (12 mL/kg of filtered water). For SDT, no signs of mortality or toxicity were observed, and the animals maintained the expected weight gain and feed intake. The RDT trials did not show mortality or signs of toxicity, as well as no change in body weight and organs, in the hematological and biochemical parameters, and also in relation to morphology and histology. Since the fermented milk did not cause any toxic effect in the conditions evaluated, it can be said that its no-adverse effect level (NOAEL) was considered to be higher than 20 mL/kg/day. Thus, the fermented milk with L. mucosae CNPC007 and inulin was considered to be of low toxicity, safe for use in rodents, and allowed for use in further studies.

Keywords: Autochthonous lactic acid bacteria; Goat dairy products; In vivo assay; No-adverse effect level; Prebiotics.