Terms of genome sequencing – no virulent genes were found –, antibiotic resistance – MIC values under EFSA breaking points – , assays to corroborate lack of production undesired metabolites -biogenic amines-, production of D- and L- lactate and bile salt hydrolase activity. Safety was also assessed by acute ingestion assays in healthy and immunosuppressed murine models –no morbidity neither weight loss, histological issues or translocation. BPL1 is in the QPS list and has self-affirmed GRAS status in the U.S .
Our screening technology behind the identification of BPL1 was founded in the use of Caenorhabditis elegans as an in vivo model for fat reduction. Accumulated fats were quantified by fluorescence after growing the nematode in the presence of each of the 23 Lactobacillus strains and 15 Bifidobacterium. The results show the highest amount of body-fat reduction in the case of BPL1, outperforming well-established probiotic strains that were also included in the study. The effect of the strain was maintained after a heat treatment (121 °C, 30 min)
The model was also used to assess the antioxidant effect of the strain, which was remarkable when compared to control conditions. The survival assay was based on an acute oxidative stress caused by the addition of H2O2. Worms fed with BPL1 showed much more resistance towards the shock (64% survival vs 34% of control).
The effect of the strain on the nematode was further evaluated by transcriptomic and metabolic assays, which led to the conclusion that the main metabolic pathways affected were energy and lipid metabolism. Feeding behavior through tryptophan metabolism, muscle contraction and a oxidative stress and inflammation response were also identified as the main changes induced by the intake of the probiotic that are related to obesity.