Probiotic Characteristics of Lactobacillus curvatus DN317, a Strain Isolated from Chicken Ceca

Abstract

The probiotic characteristics of Lactobacillus curvatus DN317, a strain isolated from chicken ceca, were evaluated. This strain was selected for study from the isolated Lactobacillus strains because it has specific anti-microbial activity against Campylobacter jejuni ATCC 33560, Camp. jejuni NCTC 11168, Listeria monocytogenes ATCC 7644, and Bacillus subtilis ATCC 8633. Lact. curvatus DN317 showed an auto-aggregation percentage of 72% and presented the highest co-aggregation with Lact. monocytogenes ATCC 7644 (68%) compared to B. subtilis ATCC 8633 (45%), Camp. jejuni ATCC 33560 (36%), and Camp. jejuni NCTC 11168 (35%). The data revealed that Lact. curvatus DN317 could survive at 0.25% bile, maintain viability at pH 2.5 for 30 min, produce biosurfactants, and adhere to Caco-2 cells. Quantification of IL-6, IL-8, IL-10, and β-defensin 2 levels shows that Lact. curvatus DN317 induces an increase in IL-8 and β-defensin 2 secretion, while the levels of IL-6 and IL-10 do not change. Lact. curvatus DN317 showed high levels of esterase and cysteine arylamidase activities (5); moderate levels of esterase lipase, β-galactosidase, and α-galactosidase activities (4, 3); and weak levels of leucine arylamidase, valine arylamidase, and acid phosphatase activity (1). Various activities were obtained of α-chymotrypsin, β-glucuronidase, β-glucosidase, and N-acetyl-β-glucosaminidase, which have been associated with intestinal diseases. Lact. curvatus DN317 lowered the cholesterol level in MRS with and without bile. Antibiotic susceptibility tests indicated that DN317 was sensitive to ampicillin, gentamicin, kanamycin, streptomycin, tetracycline, clindamycin, erythromycin, and vancomycin but was resistant to chloramphenicol and ciprofloxacin. These results suggest that Lact. curvatus DN317 could potentially function as a probiotic.

Characterization of Lactic Acid Bacteria Isolated From the Gastrointestinal Tract of a Wild Boar as Potential Probiotics

“…The antibiotic resistance in these beneficial microbes is thought to be beneficial to the survival of antibiotics in the GI tract. The probiotics with endogenous resistance can restore intestinal flora after antibiotic treatment (65). The resistance of LAB against different antibiotics is one of the most important factors for safety assessment (66).…”

Latilactobacillus curvatus: A Candidate Probiotic with Excellent Fermentation Properties and Health Benefits

“…LABs are generally sensitive to cell wall inhibitors, such as penicillin (ampicillin and piperacillin) and β-lactamase inhibitors [ 51 ]. Both L. curvatus DN317 [ 13 ] and PA40 [ 52 ] show sensitivity to penicillin and ampicillin, but L. curvatus A61 [ 53 ] is resistant to ampicillin. The main mechanism of drug resistance seems to be the impermeability of cell walls, which may be the reason for the differences between strains [ 54 ].…”

“…Furthermore, LABs are usually sensitive to antibiotics that inhibit protein synthesis (erythromycin, tetracycline, clindamycin, and chloramphenicol), but resistant to aminoglycoside drugs (neomycin, kanamycin, streptomycin, and gentamicin) [ 56 ]. However, conflicting results have been obtained for L. curvatus strains DN317 [ 13 ] and PA40 [ 52 ]. L. curvatus DN317 [ 13 ] is resistant to chloramphenicol and sensitive to gentamicin and streptomycin, whereas L. curvatus PA40 [ 52 ] is moderately resistant to erythromycin and tetracycline.…”

“…This species has also been isolated from dairy products (milk and cheese) [ 6 ]; fermented plant products, such as kimchi [ 7 , 8 , 9 ] and sourdough [ 10 ] and other plant-derived materials, such as honey [ 11 ]. Accordingly, L. curvatus has been identified in the feces or gut of many animal species that feed on plants or cereals, including snails [ 12 ], chickens [ 13 ], and humans [ 14 ].…”

Phylogenomic Analysis of Lactobacillus curvatus Reveals Two Lineages Distinguished by Genes for Fermenting Plant-Derived Carbohydrates

“…Based on this, it is perhaps not surprising that L. curvatus has also been identified in the feces or gut of many animal species that feed on plants or cereals, including snails ( Koleva et al. 2014 ), chickens ( Zommiti et al. 2017 ), and humans ( Dal Bello et al.…”