Functional Properties of Lactobacillus mucosae Strains Isolated from Brazilian Goat Milk

Abstract

The search for probiotic candidates among lactic acid bacteria (LAB) isolated from food may uncover new strains with promising health and technological properties. Lactobacillus mucosae strains attracted recent research attention due to their ability to adhere to intestinal mucus and to inhibit pathogens in the gastrointestinal tract, both related to a probiotic potential. Properties of interest and safety aspects of three Lb. mucosae strains (CNPC006, CNPC007, and CNPC009) isolated from goat milk were investigated employing in vitro tests. The presence of genetic factors related to bile salt hydrolase production (bsh), intestinal adhesion properties (msa, map, mub, and ef-tu), virulence, and biogenic amine production were also verified. All strains exhibited the target map, mub, and ef-tu sequences; the msa gene was detected in CNPC006 and CNPC007 strains. Some of the searched sequences for virulence factors were detected, especially in the CNPC009 strain; all strains carried the hyl gene, related to the production of hyaluronidase. Lb. mucosae CNPC007 exhibited a high survival rate in simulated gastric and enteric conditions. Besides, all strains exhibited the bsh sequence, and CNPC006 and CNPC007 were able to deconjugate salts of glycodeoxycholic acid (GDC). Regarding technological properties for dairy product applications, a relatively higher milk acidification and clotting capacity, diacetyl production, and proteolytic activity were registered for CNPC007 in comparison to the other strains. Collectively, the results aim at Lb. mucosae CNPC007 as a promising probiotic candidate for application in dairy products, deserving further studies to confirm and explore its potential.

Planktonic and Sessile Artificial Colonic Microbiota Harbor Distinct Composition and Reestablish Differently upon Frozen and Freeze-Dried Long-Term Storage

“…Similarly, mucosaassociated Lactobacillus mucosae and Sutterella spp. (44,45), present at abundances of 1.6% to 5.2% in sessM_F1 and sessM_F2 (Table S1 and S2), did not grow during batch incubations. Consequently, batch fermentation favors the fraction of resuspended sessile microbiota that can grow in the planktonic state and therefore represents an imperfect activity readout.…”

Lactobacillus commensals autochthonous to human milk have the hallmarks of potent probiotics

“… Controls are the cutoff points of the MIC (µg ml −1 ) of each antibiotic for L. fermentum and L. oris , respectively, beyond which a strain would be regarded as resistant according to EFSA guidelines [82] . These are as follows (for L. fermentum and L. oris , respectively); 1.0 and 1.0 µg ml −1 (clindamycin); 2.0 and 2.0 µg ml −1 (ampicillin); 1.0 and 1.0 µg ml −1 (erythromycin); 8.0 and 8.0 µg ml −1 (tetracycline); 64.0 and 64.0 µg ml −1 (kanamycin); 4.0 and 4.0 µg ml −1 (chloramphenicol); 16.0 and 16.0 µg ml −1 (gentamycin); 64.0 and 64.0 µg ml −1 (streptomycin), nr and nr (vancomycin). *‘+’ indicates growth up to 65 % of control; ‘−’ indicates significantly less growth than control (<35 %). †Inhibitory activity was scored as follows; (−) zone diameter=well diameter, no inhibition; (+) zone diameter 8–11 mm (weak); (++) diameter is between 11 and 14 mm (moderate); and (+++), zone diameter >14 mm (strong). ‡Antibiotic susceptibilities are given in µgml −1 ; nd not determined; nr , not required; R, resistant. …”

“… Controls are the cutoff points of the MIC (µg ml −1 ) of each antibiotic for L. fermentum and L. oris , respectively, beyond which a strain would be regarded as resistant according to EFSA guidelines [82] . These are as follows (for L. fermentum and L. oris , respectively); 1.0 and 1.0 µg ml −1 (clindamycin); 2.0 and 2.0 µg ml −1 (ampicillin); 1.0 and 1.0 µg ml −1 (erythromycin); 8.0 and 8.0 µg ml −1 (tetracycline); 64.0 and 64.0 µg ml −1 (kanamycin); 4.0 and 4.0 µg ml −1 (chloramphenicol); 16.0 and 16.0 µg ml −1 (gentamycin); 64.0 and 64.0 µg ml −1 (streptomycin), nr and nr (vancomycin). …”

“…The safety standards of the European Food Safety Authority (EFSA) [82] and the generally recognized as safeGenerally Recognized as Safe (GRAS) designation of the US Food and Drug Administration (FDA) [83] demand stringent safety assessments of candidate probiotics [84]. In furtherance of this, virulence traits such as haemolysis and gelatinase were checked through functional assaying and found to be absent in NPL-99.…”

Comparative Genomics Analysis of Lactobacillus mucosae from Different Niches

“…mucosae was originally found in the small intestine of piglets [9], and often occurred in the rumen of cattle later [10]. A strain of L. mucosae isolated from goat milk was recently reported [11]. Although L. mucosae has been shown to have a number of benefits to human, only two human-derived strains have been reported yet, which were isolated from childhood feces [12,13].…”