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Biodiversity and γ-aminobutyric acid production by lactic acid bacteria isolated from traditional alpine raw cow's milk cheeses.

Franciosi E, Carafa I, Nardin T, Schiavon S, Poznanski E, Cavazza A, Larcher R, Tuohy KM - Biomed Res Int (2015)

Bottom Line: Most GABA producers were Lactobacillus paracasei but other GABA producing species included Lactococcus lactis, Lactobacillus plantarum, Lactobacillus rhamnosus, Pediococcus pentosaceus, and Streptococcus thermophilus.No Enterococcus faecalis or Sc. macedonicus isolates produced GABA.The isolate producing the highest amount of GABA (80.0±2.7 mg/kg) was a Sc. thermophilus.

View Article: PubMed Central - PubMed

Affiliation: Research and Innovation Centre, Department of Food Quality and Nutrition, Fondazione Edmund Mach (FEM), Via E. Mach 1, 38010 San Michele all'Adige, Italy.

ABSTRACT
"Nostrano-cheeses" are traditional alpine cheeses made from raw cow's milk in Trentino-Alto Adige, Italy. This study identified lactic acid bacteria (LAB) developing during maturation of "Nostrano-cheeses" and evaluated their potential to produce γ-aminobutyric acid (GABA), an immunologically active compound and neurotransmitter. Cheese samples were collected on six cheese-making days, in three dairy factories located in different areas of Trentino and at different stages of cheese ripening (24 h, 15 days, and 1, 2, 3, 6, and 8 months). A total of 1,059 LAB isolates were screened using Random Amplified Polymorphic DNA-PCR (RAPD-PCR) and differentiated into 583 clusters. LAB strains from dominant clusters (n = 97) were genetically identified to species level by partial 16S rRNA gene sequencing. LAB species most frequently isolated were Lactobacillus paracasei, Streptococcus thermophilus, and Leuconostoc mesenteroides. The 97 dominant clusters were also characterized for their ability in producing GABA by high-performance liquid chromatography (HPLC). About 71% of the dominant bacteria clusters evolving during cheeses ripening were able to produce GABA. Most GABA producers were Lactobacillus paracasei but other GABA producing species included Lactococcus lactis, Lactobacillus plantarum, Lactobacillus rhamnosus, Pediococcus pentosaceus, and Streptococcus thermophilus. No Enterococcus faecalis or Sc. macedonicus isolates produced GABA. The isolate producing the highest amount of GABA (80.0±2.7 mg/kg) was a Sc. thermophilus.

No MeSH data available.


Unrooted dendrogram of the 276 dominant isolates obtained from RAPD-PCR patterns using the Pearson product moment correlation coefficient (r) and the unweighted pair group algorithm with arithmetic averages (UPGMA). Each circle-pie is a cluster and the number of slices represents the number of isolates for each cluster. GABA producer clusters are indicated by a yellow circle. Each color is a different species.
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Related In: Results  -  Collection


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fig1: Unrooted dendrogram of the 276 dominant isolates obtained from RAPD-PCR patterns using the Pearson product moment correlation coefficient (r) and the unweighted pair group algorithm with arithmetic averages (UPGMA). Each circle-pie is a cluster and the number of slices represents the number of isolates for each cluster. GABA producer clusters are indicated by a yellow circle. Each color is a different species.

Mentions: All putative LAB isolates were analyzed by RAPD-PCR as a first grouping into clusters. The isolates from the same kind of cheese showing a RAPD similarity coefficient of at least 80% were considered as belonging to a single cluster. The RAPD-PCR analysis grouped 1,059 LAB into 583 clusters with 80% similarity index (results not shown). From these clusters, 276 isolates were selected for further analysis because they belonged to the dominant microbial populations as enumerated by plate counts on MRS, MRS VAN at 30°C, M17 at 30, and 45°C. The RAPD-PCR analysis of these 276 dominant isolates discriminated 97 different clusters defined at a minimum similarity level of 80% (Figure 1). The 97 clusters were designated using a progressive number followed by the letters B, C, or D to indicate the dairy of origin of the clustered isolates (Figure 1; clusters 1D to 97C).


Biodiversity and γ-aminobutyric acid production by lactic acid bacteria isolated from traditional alpine raw cow's milk cheeses.

Franciosi E, Carafa I, Nardin T, Schiavon S, Poznanski E, Cavazza A, Larcher R, Tuohy KM - Biomed Res Int (2015)

Unrooted dendrogram of the 276 dominant isolates obtained from RAPD-PCR patterns using the Pearson product moment correlation coefficient (r) and the unweighted pair group algorithm with arithmetic averages (UPGMA). Each circle-pie is a cluster and the number of slices represents the number of isolates for each cluster. GABA producer clusters are indicated by a yellow circle. Each color is a different species.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4352725&req=5

fig1: Unrooted dendrogram of the 276 dominant isolates obtained from RAPD-PCR patterns using the Pearson product moment correlation coefficient (r) and the unweighted pair group algorithm with arithmetic averages (UPGMA). Each circle-pie is a cluster and the number of slices represents the number of isolates for each cluster. GABA producer clusters are indicated by a yellow circle. Each color is a different species.
Mentions: All putative LAB isolates were analyzed by RAPD-PCR as a first grouping into clusters. The isolates from the same kind of cheese showing a RAPD similarity coefficient of at least 80% were considered as belonging to a single cluster. The RAPD-PCR analysis grouped 1,059 LAB into 583 clusters with 80% similarity index (results not shown). From these clusters, 276 isolates were selected for further analysis because they belonged to the dominant microbial populations as enumerated by plate counts on MRS, MRS VAN at 30°C, M17 at 30, and 45°C. The RAPD-PCR analysis of these 276 dominant isolates discriminated 97 different clusters defined at a minimum similarity level of 80% (Figure 1). The 97 clusters were designated using a progressive number followed by the letters B, C, or D to indicate the dairy of origin of the clustered isolates (Figure 1; clusters 1D to 97C).

Bottom Line: Most GABA producers were Lactobacillus paracasei but other GABA producing species included Lactococcus lactis, Lactobacillus plantarum, Lactobacillus rhamnosus, Pediococcus pentosaceus, and Streptococcus thermophilus.No Enterococcus faecalis or Sc. macedonicus isolates produced GABA.The isolate producing the highest amount of GABA (80.0±2.7 mg/kg) was a Sc. thermophilus.

View Article: PubMed Central - PubMed

Affiliation: Research and Innovation Centre, Department of Food Quality and Nutrition, Fondazione Edmund Mach (FEM), Via E. Mach 1, 38010 San Michele all'Adige, Italy.

ABSTRACT
"Nostrano-cheeses" are traditional alpine cheeses made from raw cow's milk in Trentino-Alto Adige, Italy. This study identified lactic acid bacteria (LAB) developing during maturation of "Nostrano-cheeses" and evaluated their potential to produce γ-aminobutyric acid (GABA), an immunologically active compound and neurotransmitter. Cheese samples were collected on six cheese-making days, in three dairy factories located in different areas of Trentino and at different stages of cheese ripening (24 h, 15 days, and 1, 2, 3, 6, and 8 months). A total of 1,059 LAB isolates were screened using Random Amplified Polymorphic DNA-PCR (RAPD-PCR) and differentiated into 583 clusters. LAB strains from dominant clusters (n = 97) were genetically identified to species level by partial 16S rRNA gene sequencing. LAB species most frequently isolated were Lactobacillus paracasei, Streptococcus thermophilus, and Leuconostoc mesenteroides. The 97 dominant clusters were also characterized for their ability in producing GABA by high-performance liquid chromatography (HPLC). About 71% of the dominant bacteria clusters evolving during cheeses ripening were able to produce GABA. Most GABA producers were Lactobacillus paracasei but other GABA producing species included Lactococcus lactis, Lactobacillus plantarum, Lactobacillus rhamnosus, Pediococcus pentosaceus, and Streptococcus thermophilus. No Enterococcus faecalis or Sc. macedonicus isolates produced GABA. The isolate producing the highest amount of GABA (80.0±2.7 mg/kg) was a Sc. thermophilus.

No MeSH data available.